ACS Publications. Most Trusted. Most Cited. Most Read
Quick View

OR SEARCH CITATIONS

My Activity
Publications
CONTENT TYPES

Figure 1Loading Img
Download Hi-Res ImageDownload to MS-PowerPointCite This:Chem. Mater. 2022, 34, 22, 9836-9843
RETURN TO ISSUEPREVArticleNEXT

Solution Atomic Layer Deposition of Smooth, Continuous, Crystalline Metal–Organic Framework Thin Films

  • Maïssa K. S. Barr*
    Maïssa K. S. Barr
    Friedrich-Alexander-Universität Erlangen-Nürnberg, Chair Chemistry of Thin Film Materials, IZNF, Cauerstr. 3, 91058 Erlangen, Germany
    *Email: [email protected]
    More by Maïssa K. S. Barr
    Orcidhttps://orcid.org/0000-0003-1587-2269
  • , 
  • Soheila Nadiri
    Soheila Nadiri
    Friedrich-Alexander-Universität Erlangen-Nürnberg, Chair Chemistry of Thin Film Materials, IZNF, Cauerstr. 3, 91058 Erlangen, Germany
    More by Soheila Nadiri
  • , 
  • Dong-Hui Chen
    Dong-Hui Chen
    Karlsruhe Institute of Technology, Institute of Functional Interfaces (IFG), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
    More by Dong-Hui Chen
    Orcidhttps://orcid.org/0000-0003-2561-2444
  • , 
  • Peter G. Weidler
    Peter G. Weidler
    Karlsruhe Institute of Technology, Institute of Functional Interfaces (IFG), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
    More by Peter G. Weidler
  • , 
  • Sebastian Bochmann
    Sebastian Bochmann
    Friedrich-Alexander-Universität Erlangen-Nürnberg, Chair Chemistry of Thin Film Materials, IZNF, Cauerstr. 3, 91058 Erlangen, Germany
    More by Sebastian Bochmann
  • , 
  • Helmut Baumgart
    Helmut Baumgart
    Department of Electrical and Computer Engineering, Old Dominion University, Norfolk, Virginia 23529, United States
    Applied Research Center at Jefferson Labs, Newport News, Virginia 23606, United States
    More by Helmut Baumgart
  • , 
  • Julien Bachmann
    Julien Bachmann
    Friedrich-Alexander-Universität Erlangen-Nürnberg, Chair Chemistry of Thin Film Materials, IZNF, Cauerstr. 3, 91058 Erlangen, Germany
    More by Julien Bachmann
    Orcidhttps://orcid.org/0000-0001-6480-6212
  • , and 
  • Engelbert Redel*
    Engelbert Redel
    Karlsruhe Institute of Technology, Institute of Functional Interfaces (IFG), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
    *Email: [email protected]
    More by Engelbert Redel
Cite this: Chem. Mater. 2022, 34, 22, 9836–9843
Publication Date (Web):November 2, 2022
https://doi.org/10.1021/acs.chemmater.2c01102

Copyright © 2022 The Authors. Published by American Chemical Society. This publication is licensed under

CC-BY-NC-ND 4.0.
  • Open Access

Article Views

2229

Altmetric

-

Citations

3
LEARN ABOUT THESE METRICS
PDF (6 MB)
Get e-Alerts
Supporting Info (1)»

Abstract

High Resolution Image
Download MS PowerPoint Slide

For the first time, a procedure has been established for the growth of surface-anchored metal–organic framework (SURMOF) copper(II) benzene-1,4-dicarboxylate (Cu-BDC) thin films of thickness control with single molecule accuracy. For this, we exploit the novel method solution atomic layer deposition (sALD). The sALD growth rate has been determined at 4.5 Å per cycle. The compact and dense SURMOF films grown at room temperature by sALD possess a vastly superior film thickness uniformity than those deposited by conventional solution-based techniques, such as dipping and spraying while featuring clear crystallinity from 100 nm thickness. The highly controlled layer-by-layer growth mechanism of sALD proves crucial to prevent unwanted side reactions such as Ostwald ripening or detrimental island growth, ensuring continuous Cu-BDC film coverage. This successful demonstration of sALD-grown compact continuous Cu-BDC SURMOF films is a paradigm change and provides a key advancement enabling a multitude of applications that require continuous and ultrathin coatings while maintaining tight film thickness specifications, which were previously unattainable with conventional solution-based growth methods.

This publication is licensed under

CC-BY-NC-ND 4.0.
  • cc licence
  • by licence
  • nc licence
  • nd licence

Introduction

ARTICLE SECTIONS
Jump To
Metal–organic frameworks (MOFs) (1−3) can be described as crystalline three-dimensional microporous solids featuring a high surface area. They have attracted considerable attention in a wide range of applications, for example, in catalysis, (4) hydrogen storage, (5,6) gas separation, (7) thermoelectric applications, (8−10) or as chemical sensors. (11) For these applications, open coordination sites at the metal center have been demonstrated to play a crucial role. (12,13) Cu-BDC is constructed of multiple Cu paddlewheel units coordinating four 1,4-benzenedicarboxylate linkers, as shown schematically in Figure 1. (14,15) Cu-BDC is one of the most known, common, and interesting MOF materials as it can be prepared from common, commercially available, and inexpensive commodity chemicals.

Figure 1

Figure 1. Scheme of the sALD setup outlining the peristaltic pump arrangement with the connections to the reaction chamber and the growth of Cu-BDC. A corresponds to the first precursor path (Cu2(OAc)4), B to the second precursor path (terephthalic acid), and S to the solvent path (ethanol). Furthermore, the size of the Cu-BDC unit cell of 14 Å is indicated.

High Resolution Image
Download MS PowerPoint Slide
Standard atomic layer deposition (ALD) is a gas-phase thin-film deposition technique based on a sequential repetition of complementary, self-limiting reactions between volatilized molecular precursors and the solid sample surface. ALD facilitates the deposition of ultrathin films with reliable accuracy in terms of superior film thickness control at the Angstrom (Å) scale to meet the demands of the current nanotechnology, due to the strict control of the process by self-limiting gas surface reactions, enabling conformal surface coverage of device geometries with very high aspect ratios. Conventional gas-phase ALD is characterized by its cyclic operational mode in which a binary film is being synthesized by the sequential self-limited reactions between volatilized precursor and co-reactant vapors that are introduced into the reactor chamber in an alternating manner and separated by intermediate inert gas purges, thereby saturating every sample and reactor surface. Conventional ALD performed with gaseous precursors (thermally or plasma-enhanced) has become an accepted high-volume industrial technology with worldwide importance in the fields of microelectronics, electroluminescent display, and photovoltaics, specifically for the synthesis of high-k dielectric films and metal gates in MOSFET gate stacks, as dielectric layers of DRAM capacitors or as passivating layers. (16−18) ALD procedures and reactors are well established for the deposition of oxides, sulfides, nitrides, selenides, tellurides, and elemental noble metals. (19) However, important classes of thin-film materials are not accessible by conventional ALD from gaseous precursors, prominent examples being organic materials (e.g., polymers), hydrides, and ionic solids. Hybrid (metal–organic) materials have been accessed by gas-phase ALD as the so-called “molecular layer deposition” (MLD) generalization; however, the range of compounds accessible in MLD is quite narrow. (20−23) This is related to the limited choice of molecular precursors that possess sufficient thermal stability and volatility. (24,25) ZIF-8 MOF has been obtained from a conversion of ALD-grown ZnO. (26) Success in the direct growth of MOFs by ALD has remained limited. (27−30) In the literature, it is reported that the crystallinity is obtained upon post-deposition processing, either with a thermal annealing step or an extended aging at room temperature. Gas-phase deposition methods usually compete with the limited thermal stability of MOFs. However, MOF-CVD processes have been established by the group of Rob Amelot. (26,31−33)
Performing self-limited surface reactions from dissolved precursors instead of gaseous ones in “solution ALD” (sALD) broadens the range of usable precursors significantly. (34−36) The broader range of precursors, combined with the presence of solvent (at atmospheric pressure) and the low deposition temperatures, renders sALD particularly attractive for novel families of solids, in particular MOFs. So far, MOF syntheses have always relied on solution-based processing. Beyond classical solvothermal approaches for the synthesis of bulk powder, growth techniques for thin-film MOFs, or SURMOFs, rely on a volatile organic solvent which precipitates the solid upon evaporating: spin-coating, spray-coating, dip-coating, immersion, and pump methods. These traditional methods generate MOF thin films with a rather low film quality and are further handicapped by a severe lack of film thickness control, which renders them unsuitable for most applications and for all practical purposes that exclude any industrial device prospects. We note that the spray-coating method has also been presented under the phrases “liquid-phase epitaxy” (LPE) and “layer-by-layer” deposition, (37−40) which suggest a degree of relatedness higher than it may seem at first. Indeed, even if two precursors are sprayed onto the substrate sequentially (in analogy to ALD), two major differences result in a distinct growth mechanism. The facts that first, the solutions are significantly more concentrated, and second, after each step the solutions are left to dry (at least partially), concur to cause the precipitation of the solid. Therefore, in spray-coating (a.k.a. “liquid-phase epitaxy” and “layer-by-layer” deposition), the amount deposited is not controlled by surface chemistry. Correspondingly, the morphology of the deposit is far from perfection (as we will see later).
Here, we demonstrate for the first time that exploiting the sALD principles for MOF thin-film growth results in superior film quality with previously unmatched precise film thickness control at the molecular level. With sALD of Cu-BDC SURMOF, no unwanted thin-film growth mechanism has been observed such as Ostwald ripening, (41) island growth, (42) and inhomogeneous film formation. (42)
Such thin and continuous films are ideal for gas sensing applications, for instance, in which the electrical conductivity of the MOF layer is affected by condensation and/or coordination of organic analyte vapors in the open porous structure. (43) Previous MOF synthesis methods have relied on either discontinuous MOF phases (in the form of powders or islands on substrates) or their thick films. Neither of those situations is ideal for gas sensing, either due to the limited contact between the solid and the gas phase or due to the lack of homogeneous conduction across the sample, or even a combination of both. The system that we present here combines all advantageous features needed for such an application.

Experimental Methods

Substrate Preparation

Prior to deposition, Si wafer pieces of 1 × 1 to 1 × 2 cm2 size were cleaned with an oxygen plasma for 30 min, which leaves the native oxide intact. All Cu-BDC SURMOF layers were grown using sALD in a microfluidic reactor sketched in Figure 1 on nonfunctionalized Si wafers (featuring the usual amorphous native oxide SiO2), except for those dedicated to IRRAS and Raman analyses, which were grown on Au-covered Si substrates functionalized with a SAM (self-assembled monolayer) of 16-mercaptohexadecanoic acid (MHDA, 99%, Aldrich). These two types of substrates were selected as they represent the most used ones in the literature for investigating the growth of Cu-BDC with conventional solution processes.

Synthesis of Cu-BDC SURMOF Films by sALD

The deposition of Cu-BDC was carried out in a custom-built microfluidic reactor equipped with peristaltic original equipment manufacturer pumps, as described earlier by Wu, (36) Fichtner, (34) and Koch (Figure 1), and further details are provided in the Supporting Information (35) The sALD controller and software were provided by ZUMOlab. The microfluidic reactor is made out of Teflon, where four inlets supply the precursors and solvent to the sALD reactor chamber. The first (pump A) and the fourth (pump B) inlets are dedicated to delivering the two required precursors, while the second (pump S) and the third (pump S) inlets are dedicated to supplying the purge solvent.
Dicopper(II) tetraacetate (Cu2(OAc)4) and benzene-1,4-dicarboxylic acid (BDC, terephthalic acid) are used as the precursors for the copper source and the linker, respectively, while ethanol is the solvent. Both precursors are diluted in absolute ethanol (0.6 and 2 mM for copper acetate and BDC, respectively). Cu-BDC sALD proceeds by repeating the following deposition cycle: injection of the first precursor (Cu acetate, 30 s) into the reaction chamber is followed by a static exposure (30 s) and a subsequent purge with pure solvent (90 s). The sALD cycle is completed by the subsequent injection of the second precursor (benzene-1,4-dicarboxylic acid), followed by exposure and purge, using the same duration as for the first precursor. This sALD cycle is performed N times in total (10 ≤ N ≤ 400) to attain a variety of SURMOF film thicknesses. Beyond these standard parameters, successful ALD growth is demonstrated by characterizing the influence of the critical process parameters. The effect of purge duration was studied using the following ALD pulse/exposure/purge sequences: 30 s/30 s/x s (x = 30, 60, 90, 120, 150, 175). Similarly, the effect of pulse duration was investigated with the sequences y s/30 s/90 s (y = 5, 10, 20, 30, 50), and the pulse duration of both precursors was varied simultaneously. The sALD procedure closes with the solvent purge of the last cycle, after which the microfluidic chamber is open and the sample air-dried. As a comparison for benchmarking, Cu-BDC was deposited by spray-coating and dip-coating. In order to compare different deposition methods while maintaining the same chemical reactions, we grow Cu-BDC by sALD using the same precursors and solvent established in LPE and dip-coating. For the samples used in IRRAS and Raman measurements, all Cu-BDC SURMOFs used in the present work were grown on modified Au-covered substrates using the LPE method. (38) The surface modification of gold-covered substrates was carried out by depositing a SAM made from 16-mercaptohexadecanoic acid (MHDA, 99%, Aldrich). The SURMOFs were fabricated using the LPE spray method, as described in detail in previous publication. (39)
The spray times were 15 s for the Cu2(OAc)4 ethanolic solution and 25 s for the BDC ethanolic solution. Each spray step was followed by a rinsing step of 3–5 s with pure ethanol. A total of 20–150 growth cycles were used for the Cu-BDC SURMOFs investigated in this work.
The synthesis of Cu-BDC SURMOF thin films by dipping used the following procedure done by hand: Au substrates with functionalized MHDA SAMs or clean Si substrates are dipped into 1 mM Cu2(OAc)4 ethanolic solution for a duration of 30 min. After this, the sample is rinsed with ethanol. Next, the sample is placed into a 0.2 mM BDC ethanolic solution for 45 min. After this, the sample is rinsed again with ethanol.
The desired film thickness of Cu-BDC SURMOF thin films is generated through a repeated process of alternate immersion and rinsing, for example, 5, 10, 20, or 50 cycles.

Material Characterization

A SENPro spectroscopic ellipsometer from SENTECH was used to measure the resulting Cu-BDC SURMOF film thickness grown on Si substrates. All measurements were performed at a fixed angle of 70° in a spectral range of 370–1050 nm before and after sALD deposition. A Cauchy model is used to determine the thickness of Cu-BDC based on the article by Redel et al. (44) The liquid quartz crystal microbalance (QCM) cell model “openQCM” was purchased from Novaetech. AFM images were obtained with a Veeco Dimension 3100 microscope using tapping mode. Silicon probe tips from Bruker were used with a spring constant 2 N m–1 and resonance frequency 70 kHz. The resolution is 1024 × 1024 and 512 × 512 pixels for the imaged surfaces of either 2 × 2 or 20 × 20 μm2, respectively. The digital image processing was performed with Gwyddion 2.53, and the root-mean-square (rms) roughness was determined with the statistical tool embedded in the software. Masking in Figure 5d–f was performed on topographic images using 3.2, 6.2, and 4.4 nm as the thresholds. The threshold values were chosen so as to fit visually with the phase images (a,b,c). The XRD measurements in out-of-plane (coplanar) orientation were collected on a Bruker D8-Advance diffractometer equipped with a position-sensitive detector Lynxeye in θ–θ geometry, a variable divergence slit, and 2.3° Soller slit on the primary and secondary sides. The measurement was carried out in the range of 2θ = 4 to 47° at a scan step of 0.019° utilizing Cu Kα1,2 radiation (λ = 0.15406 nm) generated at 40 kV and 40 mA. For the samples prepared on Au-covered substrates, after background correction, the height correction was performed using the substrate diffraction peak positions Au(111), which were measured additionally at the end of each run. The infrared reflection–absorption spectra (IRRAS) of the samples in this study were acquired with a wavenumber resolution of 2 cm–1 using a Bruker VERTEX 80v spectrometer in grazing incidence reflection mode at an angle of incidence of 10°, using a liquid nitrogen-cooled HgTe–CdTe narrow-band detector. Perdeuterated hexadecanethiol SAMs on Au were used for reference measurements. Raman spectra were measured using a Bruker Senterra Raman microscope (Bruker Optics, Ettlingen, GER), equipped with a 50× Olympus MPLAN objective NA 0.45 and a frequency-doubled DPSS NdYAG-Laser, λ = 532 nm, operated at 200 μW output power. Each spectrum was measured with 180 s integration time using three co-additions (3 × 60 s). For data acquisition as well as spectra evaluation, the Bruker OPUS software v7.5 was used. The SEM measurements were performed on a Gemini 500, Carl Zeiss field-emission instrument.

Results and Discussion

ARTICLE SECTIONS
Jump To

Solution ALD of Cu-BDC

The sALD growth rate of Cu-BDC SURMOF films was determined by spectroscopic ellipsometry (Figure 2a) on Si substrates with a native oxide pretreated by oxygen plasma. The evolution of the film thickness of Cu-BDC as a function of the number of deposition cycles N is shown in Figure 2a for the sALD pulse/exposure/purge sequence 30 s/30 s/90 s. As expected for an ALD (or MLD) process, the thickness increases linearly with the number of ALD growth cycles (also visible from the quartz crystal microbalance data in Figure S1). The fitted linear curve intercepts the origin which indicates that there is no nucleation delay (Figure 2a). The sALD growth rate extracted from this plot is 4.5 Å/ALD cycle which corresponds exactly to one-third of a Cu-BDC unit cell, and a schematic of the growth is presented in Figure S2. This demonstrates that for one sALD deposition cycle, less than one complete monolayer is deposited mostly due to steric hindrance, which is common in ALD or MLD processes. (45) For comparison with one well-known ALD example, the growth of Al2O3 from a classic gas-phase ALD reaction also corresponds to one-third of a unit cell per cycle. (19,45) In order to confirm that the growth of Cu-BDC SURMOF films corresponds to an ALD or MLD process, it is crucial to produce evidence of the independence of the growth rate as a function of the variation of the precursor dosage. For this purpose, the pulse duration of both precursors was varied from 5 to 50 s, while the purge time was maintained at 90 s for each experiment. The evolution of the growth rate as a function of the pulse duration exhibits a plateau saturating after 10 s (Figure 2b). Pulses shorter than 10 s do not deliver sufficient precursor dosage to achieve surface saturation. This typical saturation behavior provides experimental proof of the self-limiting behavior of the surface chemistry characteristic of ALD (or MLD). In all the following experiments, a pulse duration of 30 s is adopted as the standard. An additional confirmation of self-limiting surface chemistry is provided by a purge duration variation (while the pulse is maintained constant at 30 s, Figure 2b). This experiment establishes that 90 s is the minimal purge duration needed to avoid the direct simultaneous contact and mixing between both precursors. In all following work, the purge time is kept constant at 90 s.

Figure 2

Figure 2. (a) Linear Evolution of the film thickness as a function of the number of sALD growth cycles for the sALD pulse/exposure/purge sequence of 30 s/30 s/90 s. (b) Saturation curve of the sALD growth rate as a function of the pulse and purge durations (green and blue, respectively). For the saturation study, the pulse duration of both precursors was varied simultaneously. The error bars show the uncertainty on the measurements. They correspond to the standard deviation averaged over at least 5 points measured by spectroscopic ellipsometry on a Si substrate with native oxide. The growth rate is 4.5 Å/ALD cycle.

High Resolution Image
Download MS PowerPoint Slide

Material Characterization

The chemical composition is identified by PM-IRRAS and Raman, as shown in Figure 3a. The IRRAS peaks at 2931 and 753 cm–1 wavenumbers correspond to aromatic C–H stretching and bending vibrations, respectively (46−48) Additionally, the presence of the linker is confirmed with the detection of the stretching C═C from the aromatic ring, with the emergence of the peaks at 1571 and 1507 cm–1, while the peak at 1690 cm–1 originated from the C═O group from carbonyl. (46−48) However, the coordination of the linker to the metal ion is proved by the presence of the peaks at 1629 and 1397 cm–1 which correspond to asymmetric and symmetric stretching vibrations of the ―COO– group, respectively. (49,50) No broad peaks can be detected around 3400 and 2900 cm–1. Within the limited informative value of this observation given the low signal associated with the thin film, this seems to indicate that neither water nor ethanol has been trapped in the SURMOF pores. (48) The Raman spectra also provide another independent confirmation of the presence of the linker. The Raman peaks at 3077, 1641, and 1441 cm–1 are attributed to C–H, C═C, and C–O, respectively. (48,49) Additionally, the presence of the BDC ring is clarified with the presence of the peak at 1140 cm–1. (48,49) The chemical composition does not vary with the increase of the thickness. The PM-IRRAS and Raman spectra are identical for 50 and 200 sALD cycles (Figure S3). The crystalline structure of Cu-BDC grown by sALD has been identified by X-ray diffraction in Cu-BDC films grown with 50, 100, 200, 300, and 400 ALD deposition cycles, as depicted in Figure 3b. The sole XRD reflection at 2θ = 8.3° can be indexed to the presence of crystalline Cu-BDC and is the only one detected over the range between 0° and 30°; the full diffractogram is shown in Figure S4, and the peak detected at 23° is attributed to the sample holder. (32) However, for ALD deposition cycles less than 200 cycles, no XRD peak can be observed neither in Bragg–Brentano geometry nor in grazing incidence geometry due to the extremely low thickness of the SURMOF layer resulting in insufficient information volume. This indicates that the film most likely starts out in amorphous phase or mixed amorphous phase with embedded nanocrystallites or insufficient information volume in the thin film for XRD to pick up any crystal reflection signal from the onset of crystalline nucleation. Then, it crystallizes once the Cu-BDC film exceeds a critical thickness of about 100 nm which could correspond to the formation of an extended lattice providing sufficient driving force for crystallization or when there is sufficient information volume in the sample to detect the single growth revealed by the single XRD reflection at 8.3°. From 200 to 400 cycles, the intensity of XRD reflection increases with the number of ALD cycles, and this provides the experimental evidence of an oriented crystalline state of Cu-BDC, which is a necessary requirement for a SURMOF film. For the sample with 400 cycles, a second order peak (200) was observed. As no other peaks were detected, a preferred orientation along the [100] direction must be concluded. Our work is the first study, which demonstrates the growth of crystalline Cu-BDC film at room temperature with an ALD/MLD process without thermal treatment.

Figure 3

Figure 3. (a) PM-IRRAS and Raman spectra of Cu-BDC grown by sALD with 50 ALD cycles and (b) XRD diffractogram of Cu-BDC grown by sALD with 50, 100, 200, 300, and 400 ALD cycles.

High Resolution Image
Download MS PowerPoint Slide
The surface morphology and the roughness of Cu-BDC SURMOF films deposited by sALD have been characterized by SEM and AFM (Figure 4). The SEM micrograph of a Cu-BDC film after 10 sALD cycles is presented in Figure 4a. The relatively featureless image is consistent with a compact, dense, and continuous film, in stark contrast to the typical prevailing morphology of Cu-BDC deposited by conventional methods of spray-coating or dip-coating, which consists mostly of nanosheets, needles, or large particles. (32,47,51,52) The homogeneity is retained for larger numbers of cycles (Figure S5). A cross-sectional micrograph and an EDX spectrum which confirm the compactness of the layer and the presence of Cu-BDC are shown in Figure S6. The Cu-BDC SURMOF film continuity and morphological quality are further proven by AFM analysis. The AFM topographic micrographs reveal small grainy features homogeneously distributed over the film, in a manner similar to the SEM display (Figure 4b,d). The phase contrast image confirms that the Cu-BDC film coverage is already continuous after 10 sALD growth cycles (Figure 4c).

Figure 4

Figure 4. Microscopic characterization of Cu-BDC films grown with 10 sALD cycles. (a) SEM micrograph of surface morphology and (b) AFM micrograph of Cu-BDC film grown with 10 deposition cycles by sALD. (c) Phase contrast data of the AFM micrograph (scale −75 to 75°). (d) Low-magnification AFM micrograph of the same film. Micrographs (b) and (c) display the same area of the film, which differs from those shown in (a) and (d). The rms roughness obtained from image (d) is 5.1 nm.

High Resolution Image
Download MS PowerPoint Slide
For benchmarking, a direct comparison of sALD SURMOF films is provided with films deposited with similar thickness (4.5 nm) by the other conventional methods seen in the micrographs in Figure 5. The low nominal film thickness was chosen so as to emphasize the critical differences pertaining to film continuity most clearly (given that most films will eventually evolve into continuous layers beyond a certain thickness). Here, the AFM phase contrast images (a,b,c) exhibit a very different pattern for the sALD case (a) versus the two conventional deposition methods of dip-coating and spray-coating (b,c): in these latter two cases, the AFM micrographs reveal discontinuous Cu-BDC films of clearly separate islands interrupted by large areas which are perfectly smooth, corresponding to the empty SiO2 substrate surface, indicating the missing Cu-BDC film, whereas in the sALD case (a), the resulting Cu-BDC film is completely continuous with homogeneous surface coverage. Taking these smooth areas as the empty native SiO2 substrate surface with no discernible Cu-BDC film, we apply a threshold mask to the topographic images (d,e,f) in order to highlight the areas left noncovered by dip-coating and spray-coating, also called “liquid-phase epitaxy” or “layer-by-layer” deposition. (37−40) Clearly, the sALD method achieves the crucially important homogeneous nucleation and growth completely covering the entire sample surface, whereas the less-controlled conventional methods yield only localized nucleation and formation of isolated islands with a lot of empty space in between characterized by the missing film. Importantly, this statement remains valid even for the spray-coating method, which also features sequential delivery of two distinct precursor solutions but without the self-limiting surface chemical nature of ALD. (38−41) The improvement in the achieved performance of the sALD thin-film growth is best illustrated in a direct comparison of how much surface area film coverage can be achieved by each method, which measures the percentage of continuous film coverage of the sample surface. In the sALD case, the covered area by the SURMOF film represents 99.6% of the entire sample surface (based on the 25 μm2 shown) but only 33.1 and 28.2% for the other two conventional growth methods of dip-coating and spray-coating. This discontinuous island growth mechanism (also known as the Volmer–Weber thin-film growth characterized by heterogeneous nucleation), as well as Ostwald ripening, is typically reported for MOFs grown by conventional methods and constitutes a fundamental limitation for dip-coating and spray-coating. (36) It is precisely the lack of homogeneous nucleation combined with self-limiting surface-saturating chemical precursor reactions, which is intrinsic to sALD, that relegates dip-coating and spray-coating to the vastly inferior Cu-BDC film quality. A further advantage of the sALD method is the excellent adhesion that it confers on the film (Figure S7).

Figure 5

Figure 5. (a,d) AFM micrographs of Cu-BDC deposited by sALD with 10 deposition cycles, (b,e) dip-coating, and (c,f) spray-coating (a. k. a. “liquid-phase epitaxy” and “layer-by-layer” deposition). The micrographs (a–c) represent the phase contrast (the value varies between 0 and 70°) and (d–f) are the respective topographic data with a threshold mask, the height scale varying from 0 to 50 nm for (d,e) and from 0 to 25 nm for (f). The corresponding mask appears in red, and the unmasked region appears in black and white. The details of masking are described in the Experimental Methods section. The lateral scale bar represents 250 nm.

High Resolution Image
Download MS PowerPoint Slide
Thus, our experimental results demonstrate a crucial advantage of sALD and establish it as the method of choice for depositing ultrathin (<10 nm), homogeneous, compact, and continuous crystalline Cu-BDC SURMOF layers. This paradigm-changing breakthrough opens up SURMOF film technology to entirely new application fields. The compelling advantages of surface saturation in absolutely conformal thin-film coatings with subnanometer precision that propelled classical gas-phase ALD technology to the leading edge in microelectronics have now been transferred to solution-processed material systems such as MOFs. We expect that this fruitful combination will open up many opportunities in areas such as sensing, optical coatings, and printed electronics and launch renewed interest to extend the sALD method beyond MOFs to organic materials (e.g., polymers), hydrides, and ionic solids.

Conclusions

ARTICLE SECTIONS
Jump To
A solution atomic layer deposition (sALD) process has been established for the direct deposition of SURMOF (surface-anchored metal–organic framework) Cu-BDC as thin compact continuous films in crystalline, oriented form at room temperature. The use of sALD is unprecedented in the field of MOFs and SURMOFs and is key to controlling growth down to the atomic or molecular resolution. With respect to the more broadly established gas-phase ALD, sALD provides the ability to handle nonvolatile precursor components and requires specially designed yet simple microfluidic reactors to enable true ALD self-limiting surface-saturating chemical precursor reactions in solution. The fact that SURMOF films grown by sALD exhibit a perfect film continuity even for thicknesses below 10 nm with Angstrom thickness control represents a paradigm change, in contrast to the discontinuous islands obtained by the Volmer–Weber growth mechanism which limits the achievable film quality of the conventional SURMOF dip-coating and spray-coating methods of Cu-BDC. The growth rate of 4.5 Å per sALD cycle defines the thickness resolution achievable, which corresponds to one-third of the unit cell.
This places sALD centrally on the MOF technology map. In the near future, the compelling and inevitable generalization of the Cu-BDC sALD reaction demonstrated here to other MOF compounds and its expansion to large-area coatings will most certainly enable practical applications of various SURMOF films, with gas sensors as one prominent example. Furthermore, the unique ability of sALD to conformally coat nonplanar, macroporous substrates represents an attractive tool to enhance the performance of many devices via tuning the surface-to-volume ratio of the functional material. This sALD breakthrough for Cu-BDC SURMOF thin films opens up a novel approach to synthesizing SURMOF films that are in compliance with the most stringent thin-film specification requirements in the nanotechnology area and thus will potentially lead to new SURMOF device applications not yet foreseen.

Supporting Information

ARTICLE SECTIONS
Jump To

The Supporting Information is available free of charge at https://pubs.acs.org/doi/10.1021/acs.chemmater.2c01102.

  • Detailed description of the experimental methods and used materials; additional QCM measurements; scheme of the growth of Cu-BDC SURMOF by sALD sALD setup; ; and additional characterization data of Cu-BDC (PDF)

Terms & Conditions

Most electronic Supporting Information files are available without a subscription to ACS Web Editions. Such files may be downloaded by article for research use (if there is a public use license linked to the relevant article, that license may permit other uses). Permission may be obtained from ACS for other uses through requests via the RightsLink permission system: http://pubs.acs.org/page/copyright/permissions.html.

Author Information

ARTICLE SECTIONS
Jump To
  • Corresponding Authors
    • Maïssa K. S. Barr - Friedrich-Alexander-Universität Erlangen-Nürnberg, Chair Chemistry of Thin Film Materials, IZNF, Cauerstr. 3, 91058 Erlangen, Germany;  Orcidhttps://orcid.org/0000-0003-1587-2269;  Email: [email protected]
    • Engelbert Redel - Karlsruhe Institute of Technology, Institute of Functional Interfaces (IFG), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany;  Email: [email protected]
  • Authors
    • Soheila Nadiri - Friedrich-Alexander-Universität Erlangen-Nürnberg, Chair Chemistry of Thin Film Materials, IZNF, Cauerstr. 3, 91058 Erlangen, Germany
    • Dong-Hui Chen - Karlsruhe Institute of Technology, Institute of Functional Interfaces (IFG), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany;  Orcidhttps://orcid.org/0000-0003-2561-2444
    • Peter G. Weidler - Karlsruhe Institute of Technology, Institute of Functional Interfaces (IFG), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
    • Sebastian Bochmann - Friedrich-Alexander-Universität Erlangen-Nürnberg, Chair Chemistry of Thin Film Materials, IZNF, Cauerstr. 3, 91058 Erlangen, Germany
    • Helmut Baumgart - Department of Electrical and Computer Engineering, Old Dominion University, Norfolk, Virginia 23529, United States;  Applied Research Center at Jefferson Labs, Newport News, Virginia 23606, United States
    • Julien Bachmann - Friedrich-Alexander-Universität Erlangen-Nürnberg, Chair Chemistry of Thin Film Materials, IZNF, Cauerstr. 3, 91058 Erlangen, Germany;  Orcidhttps://orcid.org/0000-0001-6480-6212
  • Author Contributions

    H.B., E.R., and J.B. initiated the project with the first concept ideas of SURMOF sALD. S.N. performed the deposition and SE characterization; D. C performed the Raman and PM-IRRAS characterizations; P.G.W. performed the XRD measurements; S.B. performed the SEM analysis; M. K.S.B. performed the AFM measurements and the analysis of the data; and M.K.S.B., H.B., E.R., and J.B. wrote the manuscript.

  • Notes
    The authors declare no competing financial interest.

Acknowledgments

ARTICLE SECTIONS
Jump To

Financial support was provided by the Deutsche Forschungsgemeinschaft (DFG) within the COORNET Priority Program (SPP 1928), the European Research Council (ERC) in the ERC Consolidator Grant ‘Solacylin’ (grant agreement 647281), and by FAU via the excellence cluster “Engineering of Advanced Materials” and the “Emerging Talents Initiative”. E.R. thanks KIT for sustainable research funding. D.C. acknowledges the financial support of the Chinese Scholarship Council (CSC). Further support from the KNMF (Karlsruhe Nano Micro Facility) is gratefully acknowledged. The authors are thankful to Ryan W. Crisp for proofreading.

References

ARTICLE SECTIONS
Jump To

This article references 52 other publications.

  1. 1
    James, S. L. Metal-organic frameworks. Chem. Soc. Rev. 2003, 32, 276– 288,  DOI: 10.1039/b200393g
    Google Scholar
    1
    Metal-organic frameworks
    James, Stuart L.
    Chemical Society Reviews (2003), 32 (5), 276-288CODEN: CSRVBR; ISSN:0306-0012. (Royal Society of Chemistry)
    A review. Metal-org. frameworks are a recently-identified class of porous polymeric material, consisting of metal ions linked together by org. bridging ligands, and are a new development on the interface between mol. coordination chem. and materials science. A range of novel structures was prepd. which feature amongst the largest pores known for cryst. compds., very high sorption capacities and complex sorption behavior not seen in aluminosilicate zeolites. The development of synthetic approaches to these materials and studies of their properties are reviewed.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD3sXmtFOltLY%253D&md5=e9e83de0580c0b7dc9929ea3594efe12
  2. 2
    Li, H.; Eddaoudi, M.; O’Keeffe, M.; Yaghi, O. M. Design and synthesis of an exceptionally stable and highly porous metal-organic framework. Nature 1999, 402, 276– 279,  DOI: 10.1038/46248
    Google Scholar
    2
    Design and synthesis of an exceptionally stable and highly porous metal-organic framework
    Li, Hailian; Eddaoudi, Mohamed; O'Keeffe, M.; Yaghi, M.
    Nature (London) (1999), 402 (6759), 276-279CODEN: NATUAS; ISSN:0028-0836. (Macmillan Magazines)
    Open metal-org. frameworks are widely regarded as promising materials for applications in catalysis, sepn., gas storage and mol. recognition. Compared to conventionally used microporous inorg. materials such as zeolites, these org. structures have the potential for more flexible rational design, through control of the architecture and functionalization of the pores. So far, the inability of these open frameworks to support permanent porosity and to avoid collapsing in the absence of guest mols., such as solvents, has hindered further progress in the field. The authors report the synthesis of a metal-org. framework, Zn4O(BDC)3.(DMF)8.(PhCl) (named MOF-5, where BDC = 1,4-benzenedicarboxylate), which remains cryst., as evidenced by x-ray single-crystal analyses, and stable when fully desolvated and when heated up to 300°. This synthesis is achieved by borrowing ideas from metal carboxylate cluster chem., where an org. dicarboxylate linker was used in a reaction that gives supertetrahedron clusters when capped with monocarboxylates. The rigid and divergent character of the added linker allows the articulation of the clusters into a three-dimensional framework resulting in a structure with higher apparent surface area and pore vol. than most porous cryst. zeolites. This simple and potentially universal design strategy is currently being pursued in the synthesis of new phases and composites, and for gas-storage applications.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaK1MXnvFSiuro%253D&md5=68f27e20a7e4e15ea2c2f49a2a61e98a
  3. 3
    Rowsell, J. L. C.; Yaghi, O. M. Metal-organic frameworks: a new class of porous materials. Microporous Mesoporous Mater. 2004, 73, 3– 14,  DOI: 10.1016/j.micromeso.2004.03.034
    Google Scholar
    3
    Metal-organic frameworks: a new class of porous materials
    Rowsell, Jesse L. C.; Yaghi, Omar M.
    Microporous and Mesoporous Materials (2004), 73 (1-2), 3-14CODEN: MIMMFJ; ISSN:1387-1811. (Elsevier Science B.V.)
    A review of the synthesis, structure, and properties of metal-org. frameworks (MOFs) is presented, highlighting the important advances in their research over the past decade. This new class of porous materials is attracting attention due to demonstrations of their large pore sizes, high apparent surface areas, selective uptake of small mols., and optical or magnetic responses to the inclusion of guests. More importantly, their synthesis from mol. building blocks holds the potential for directed tailoring of these properties.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD2cXlvVWrur4%253D&md5=63063a3480702ad0f211a6d5f0fd0491
  4. 4
    Lee, J.; Farha, O. K.; Roberts, J.; Scheidt, K. A.; Nguyen, S. T.; Hupp, J. T. Metal-organic framework materials as catalysts. Chem. Soc. Rev. 2009, 38, 1450– 1459,  DOI: 10.1039/b807080f
    Google Scholar
    4
    Metal-organic framework materials as catalysts
    Lee, Jeong Yong; Farha, Omar K.; Roberts, John; Scheidt, Karl A.; Nguyen, Son Binh T.; Hupp, Joseph T.
    Chemical Society Reviews (2009), 38 (5), 1450-1459CODEN: CSRVBR; ISSN:0306-0012. (Royal Society of Chemistry)
    A review; a crit. review of the emerging field of MOF-based catalysis is presented. Discussed are examples of: (a) opportunistic catalysis with metal nodes, (b) designed catalysis with framework nodes, (c) catalysis by homogeneous catalysts incorporated as framework struts, (d) catalysis by MOF-encapsulated mol. species, (e) catalysis by metal-free org. struts or cavity modifiers, and (f) catalysis by MOF-encapsulated clusters.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD1MXkvVamu7k%253D&md5=d9cef4eb52ffb1c73fe1195e11bace26
  5. 5
    Babaei, H., DeCoster, M. E., Jeong, M., Hassan, Z. M., Islamoglu, T., Baumgart, H., McGaughey, A. J. H., Redel, E., Farha, O. K., Hopkins, P. E., Malen, J. A., Wilmer, C. E. Observation of reduced thermal conductivity in a metal-organic framework due to the presence of adsorbates. Nat. Commun. 2020, 11(). DOI: 10.1038/s41467-020-17822-0
    Google Scholar
    There is no corresponding record for this reference.
  6. 6
    Murray, L. J.; Dincă, M.; Long, J. R. Hydrogen storage in metal-organic frameworks. Chem. Soc. Rev. 2009, 38, 1294– 1314,  DOI: 10.1039/b802256a
    Google Scholar
    6
    Hydrogen storage in metal-organic frameworks
    Murray, Leslie J.; Dinca, Mircea; Long, Jeffrey R.
    Chemical Society Reviews (2009), 38 (5), 1294-1314CODEN: CSRVBR; ISSN:0306-0012. (Royal Society of Chemistry)
    A review of current status of hydrogen storage within metal-org. frameworks. Microporous metal-org. frameworks, having exceptionally high surface areas and chem.-tunable structures, have recently emerged as some of the most promising candidate materials. Particular emphasis is given to the relationships between structural features and the enthalpy of hydrogen adsorption, spectroscopic methods for probing framework-H2 interactions, and strategies for improving storage capacity.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD1MXkvVamuro%253D&md5=f652ac03772753d7f80244564a80e6f0
  7. 7
    Li, J. R.; Sculley, J.; Zhou, H. C. Metal-Organic Frameworks for Separations. Chem. Rev. 2012, 112, 869– 932,  DOI: 10.1021/cr200190s
    Google Scholar
    7
    Metal-Organic Frameworks for Separations
    Li, Jian-Rong; Sculley, Julian; Zhou, Hong-Cai
    Chemical Reviews (Washington, DC, United States) (2012), 112 (2), 869-932CODEN: CHREAY; ISSN:0009-2665. (American Chemical Society)
    A review. This article reviews the metal-org. frameworks (MOFs), a new class of porous solid materials. Their performances for applications in sepns. and purifications is attracting intense interest of researchers working in the fields of chem., chem. engineering, materials science, and others. Despite being in its infancy, the research progress in this subject has already shown that MOFs are promising for sepn. applications.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3MXht1OnsbbL&md5=635f36e2682f7fbc651f5021d591a1cf
  8. 8
    Chen, X.; Wang, Z.; Lin, P.; Zhang, K.; Baumgart, H.; Redel, E.; Wöll, C. Thermoelectric Properties of Highly Ordered Metal-Organic Framework Films. ECS Trans. 2016, 75, 119– 126,  DOI: 10.1149/07513.0119ecst
    Google Scholar
    8
    Thermoelectric properties of highly ordered metal-organic framework films
    Chen, Xin; Wang, Zhengbang; Lin, Pengtao; Zhang, Kai; Baumgart, Helmut; Redel, Engelbert; Woll, Christof
    ECS Transactions (2016), 75 (13, Emerging Nanomaterials and Devices), 119-126CODEN: ECSTF8; ISSN:1938-5862. (Electrochemical Society)
    In this work, quasi-liq. epitaxially highly oriented Surface Anchored Metal-Org. Framework (SURMOF) films and for comparison random polycryst. MOF films loaded with tetracyano-quinodimethane (TCNQ) infiltration were fabricated and characterized. The horizontal Seebeck coeff. of the oriented SURMOF films and the random polycryst. MOF films parallel to the sample surface was measured and has been discussed. The polycryst. MOF films exhibit a high Seebeck coeff. of 949.9 μV/K at 290 K, while the horizontal Seebeck coeff. of oriented SURMOF films is practically around 0 μV/K. Because the quasi-epitaxial oriented SURMOF films are highly anisotropic, there is no measurable horizontal carrier transport parallel to the SURMOF surface. However in contrast to oriented SURMOF films, the elec. properties of random polycryst. MOF films with sputtered Au contact pads could be measured. The high Seebeck coeff. of these random polycryst. MOF films demonstrate a promising application potential of MOF films in future thermoelec. and electronic devices.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1cXovVentrw%253D&md5=1cda3bed0a6b737b4c04f4cb06c97c58
  9. 9
    Chen, X.; Wang, Z. B.; Hassan, Z. M.; Lin, P. T.; Zhang, K.; Baumgart, H.; Redel, E. Seebeck Coefficient Measurements of Polycrystalline and Highly Ordered Metal-Organic Framework Thin Films. ECS J. Solid State Sci. Technol. 2017, 6, P150– P153,  DOI: 10.1149/2.0161704jss
    Google Scholar
    9
    Seebeck Coefficient Measurements of Polycrystalline and Highly Ordered Metal-Organic Framework Thin Films
    Chen, Xin; Wang, Zhengbang; Hassan, Zeinab Mohamed; Lin, Pengtao; Zhang, Kai; Baumgart, Helmut; Redel, Engelbert
    ECS Journal of Solid State Science and Technology (2017), 6 (4), P150-P153CODEN: EJSSBG; ISSN:2162-8769. (Electrochemical Society)
    In this work highly oriented Surface Anchored Metal-Org. Framework (SURMOF) films were fabricated quasi-epitaxial and were elec. characterized by Seebeck anal. and benchmarked against random polycryst. MOF films loaded with tetracyano-quinodimethane (TCNQ) infiltration. The horizontal Seebeck coeff. of the oriented SURMOF films and the random polycryst. MOF films parallel to the sample surface was measured and has been discussed. The isotropic random polycryst. MOF films exhibit a high pos. Seebeck coeff. of 422.32 μV/K at 350 K. However, the horizontal Seebeck coeff. of highly oriented SURMOF films fluctuates around 0 μV/K instead. Because the quasi-epitaxial oriented SURMOF films are highly anisotropic, there is no measurable horizontal carrier transport parallel to the SURMOF surface. However, in contrast to highly oriented (002) SURMOF films, the in-plane thermoelec. properties of random polycryst. MOF films with sputtered Au contact pads could be measured due to the isotropic nature of these films. The high Seebeck coeff. of these random polycryst. MOF films demonstrates promising application potential of MOF films in future thermoelec. and electronic devices.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2sXktlKisLs%253D&md5=3115ad94f6d16cfdd737079b24360e53
  10. 10
    Redel, E.; Baumgart, H. Thermoelectric porous MOF based hybrid materials. APL Mater. 2020, 8, 060902,  DOI: 10.1063/5.0004699
    Google Scholar
    10
    Thermoelectric porous MOF based hybrid materials
    Redel, Engelbert; Baumgart, Helmut
    APL Materials (2020), 8 (6), 060902CODEN: AMPADS; ISSN:2166-532X. (American Institute of Physics)
    Porous hybrid materials and MOF (Metal-Org.-Framework) films represent modern designer materials that exhibit many requirements of a near ideal and tunable future thermoelec. (TE) material. In contrast to traditional semiconducting bulk TE materials, porous hybrid MOF templates can be used to overcome some of the constraints of physics in bulk TE materials. These porous hybrid systems are amenable for simulation and modeling to design novel optimized electron-crystal phonon-glass materials with potentially very high ZT (figure of merit) nos. Porous MOF and hybrid materials possess an ultra-low thermal cond., which can be further modulated by phonon engineering within their complex porous and hierarchical architecture to advance the TE figure of merit (ZT). This Perspective review discusses recent results of MOF TE materials and provides a future outlook and the vision to the search for the next generation TE porous hybrid and MOF materials, which could be part of the green renewable energy revolution with novel materials of sustainably high ZT values. (c) 2020 American Institute of Physics.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BB3cXhtFGhtbrK&md5=59f2d78fc71aabbf6ad2b164c15adc2b
  11. 11
    Kreno, L. E.; Leong, K.; Farha, O. K.; Allendorf, M.; Van Duyne, R. P.; Hupp, J. T. Metal-Organic Framework Materials as Chemical Sensors. Chem. Rev. 2012, 112, 1105– 1125,  DOI: 10.1021/cr200324t
    Google Scholar
    11
    Metal-Organic Framework Materials as Chemical Sensors
    Kreno, Lauren E.; Leong, Kirsty; Farha, Omar K.; Allendorf, Mark; Van Duyne, Richard P.; Hupp, Joseph T.
    Chemical Reviews (Washington, DC, United States) (2012), 112 (2), 1105-1125CODEN: CHREAY; ISSN:0009-2665. (American Chemical Society)
    A review. The authors present a crit. review of the literature on metal-org. frameworks (MOFs) as chem. sensors. The authors begin by briefly examg. challenges relating to MOF sensor development including the design of MOFs with desirable properties, incorporation of appropriate signal transduction capabilities, and integration of MOFs into devices by employing thin-film growth techniques. Subsequent sections discuss specific examples of MOF sensors, categorized by method of signal transduction. Sensors based on MOF photoluminescence are discussed briefly. The authors have limited the review of luminescence-based sensors to a small no. of recent reports where the porous MOF architecture, or its chem. compn., imparts selective sensing capabilities. Scintillating MOFs that luminesce in the presence of radioactive analytes are also discussed. Other signal transduction schemes that use photons include various kinds of optical interferometry, analyte modulation of localized surface plasmon resonance energies, and solvatochromism. Mech. signal-transduction schemes employed with MOFs include ones based on surface acoustic wave, quartz crystal microbalance, and microcantilever devices. Elec. schemes thus far were limited to ones based on impedance spectroscopy.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3MXhsVCgtL%252FI&md5=f6ed572725bc067ee8da81880bf1ec90
  12. 12
    Bloch, E. D.; Murray, L. J.; Queen, W. L.; Chavan, S.; Maximoff, S. N.; Bigi, J. P.; Krishna, R.; Peterson, V. K.; Grandjean, F.; Long, G. J.; Smit, B.; Bordiga, S.; Brown, C. M.; Long, J. R. Selective Binding of O-2 over N-2 in a Redox-Active Metal-Organic Framework with Open Iron(II) Coordination Sites. J. Am. Chem. Soc. 2011, 133, 14814– 14822,  DOI: 10.1021/ja205976v
    Google Scholar
    12
    Selective Binding of O2 over N2 in a Redox-Active Metal-Organic Framework with Open Iron(II) Coordination Sites
    Bloch, Eric D.; Murray, Leslie J.; Queen, Wendy L.; Chavan, Sachin; Maximoff, Sergey N.; Bigi, Julian P.; Krishna, Rajamani; Peterson, Vanessa K.; Grandjean, Fernande; Long, Gary J.; Smit, Berend; Bordiga, Silvia; Brown, Craig M.; Long, Jeffrey R.
    Journal of the American Chemical Society (2011), 133 (37), 14814-14822CODEN: JACSAT; ISSN:0002-7863. (American Chemical Society)
    The air-free reaction between FeCl2 and H4dobdc (dobdc4- = 2,5-dioxido-1,4-benzenedicarboxylate) in a mixt. of N,N-dimethylformamide (DMF) and methanol affords Fe2(dobdc)·4DMF, a metal-org. framework adopting the MOF-74 (or CPO-27) structure type. The desolvated form of this material displays a Brunauer-Emmett-Teller (BET) surface area of 1360 m2/g and features a hexagonal array of one-dimensional channels lined with coordinatively unsatd. FeII centers. Gas adsorption isotherms at 298 K indicate that Fe2(dobdc) binds O2 preferentially over N2, with an irreversible capacity of 9.3%, corresponding to the adsorption of one O2 mol. per two iron centers. Remarkably, at 211 K, O2 uptake is fully reversible and the capacity increases to 18.2%, corresponding to the adsorption of one O2 mol. per iron center. Mossbauer and IR spectra are consistent with partial charge transfer from iron(II) to O2 at low temp. and complete charge transfer to form iron(III) and O22- at room temp. The results of Rietveld analyses of powder neutron diffraction data (4 K) confirm this interpretation, revealing O2 bound to iron in a sym. side-on mode with dO-O = 1.25(1) Å at low temp. and in a slipped side-on mode with dO-O = 1.6(1) Å when oxidized at room temp. Application of ideal adsorbed soln. theory in simulating breakthrough curves shows Fe2(dobdc) to be a promising material for the sepn. of O2 from air at temps. well above those currently employed in industrial settings.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3MXhtV2isbnM&md5=bb45728676bb33f13be541d2cc6d0279
  13. 13
    Bloch, E. D.; Queen, W. L.; Krishna, R.; Zadrozny, J. M.; Brown, C. M.; Long, J. R. Hydrocarbon Separations in a Metal-Organic Framework with Open Iron(II) Coordination Sites. Science 2012, 335, 1606– 1610,  DOI: 10.1126/science.1217544
    Google Scholar
    13
    Hydrocarbon Separations in a Metal-Organic Framework with Open Iron(II) Coordination Sites
    Bloch, Eric D.; Queen, Wendy L.; Krishna, Rajamani; Zadrozny, Joseph M.; Brown, Craig M.; Long, Jeffrey R.
    Science (Washington, DC, United States) (2012), 335 (6076), 1606-1610CODEN: SCIEAS; ISSN:0036-8075. (American Association for the Advancement of Science)
    The energy costs assocd. with large-scale industrial sepn. of light hydrocarbons by cryogenic distn. could potentially be lowered through development of selective solid adsorbents that operate at higher temps. Here, the metal-org. framework Fe2(dobdc) (dobdc4- : 2,5-dioxido-1,4-benzenedicarboxylate) is demonstrated to exhibit excellent performance characteristics for sepn. of ethylene/ethane and propylene/propane mixts. at 318 K. Breakthrough data obtained for these mixts. provide exptl. validation of simulations, which in turn predict high selectivities and capacities of this material for the fractionation of methane/ethane/ethylene/acetylene mixts., removal of acetylene impurities from ethylene, and membrane-based olefin/paraffin sepns. Neutron powder diffraction data confirm a side-on coordination of acetylene, ethylene, and propylene at the iron(II) centers, while also providing solid-state structural characterization of the much weaker interactions of ethane and propane with the metal.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC38XksVyqsLc%253D&md5=d149ed45c3e688d5e4ee63d75629bd4f
  14. 14
    Borfecchia, E.; Maurelli, S.; Gianolio, D.; Groppo, E.; Chiesa, M.; Bonino, F.; Lamberti, C. Insights into Adsorption of NH3 on HKUST-1 Metal–Organic Framework: A Multitechnique Approach. J. Phys. Chem. C 2012, 116, 19839– 19850,  DOI: 10.1021/jp305756k
    Google Scholar
    14
    Insights into Adsorption of NH3 on HKUST-1 Metal-Organic Framework: A Multitechnique Approach
    Borfecchia, Elisa; Maurelli, Sara; Gianolio, Diego; Groppo, Elena; Chiesa, Mario; Bonino, Francesca; Lamberti, Carlo
    Journal of Physical Chemistry C (2012), 116 (37), 19839-19850CODEN: JPCCCK; ISSN:1932-7447. (American Chemical Society)
    We report a careful characterization of the interaction of NH3 with the Cu(II) sites of the [Cu2C4O8] paddle-wheel cornerstone of the HKUST-1 metallorg. framework, also known as Cu3(BTC)2. The general picture emerging from combining XRPD, EXAFS, XANES, mid- and far-IR, DRUV-vis, and EPR techniques is that the presence of traces of water has relevant consequences on the effect of ammonia on the MOF framework. NH3 adsorption on the dry system results in a strong chemisorption on Cu(II) sites that distorts the framework, keeping the crystallinity of the material. Perturbation obsd. upon NH3 adsorption is analogous to that obsd. for H2O, but noticeably enhanced. When the adsorption of ammonia occurs in humid conditions, a time-dependent, much deeper modification of the system is obsd. by all of the considered techniques. On a methodol. ground, it is worth noticing that we used the optimization of XANES spectra to validate the bond distance obtained by EXAFS.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC38XhtFChtbvO&md5=9ac9922154e664d3bfa180e2caf761a9
  15. 15
    Kim, H. K.; Yun, W. S.; Kim, M.-B.; Kim, J. Y.; Bae, Y.-S.; Lee, J.; Jeong, N. C. A Chemical Route to Activation of Open Metal Sites in the Copper-Based Metal–Organic Framework Materials HKUST-1 and Cu-MOF-2. J. Am. Chem. Soc. 2015, 137, 10009– 10015,  DOI: 10.1021/jacs.5b06637
    Google Scholar
    15
    A Chemical Route to Activation of Open Metal Sites in the Copper-Based Metal-Organic Framework Materials HKUST-1 and Cu-MOF-2
    Kim, Hong Ki; Yun, Won Seok; Kim, Min-Bum; Kim, Jeung Yoon; Bae, Youn-Sang; Lee, JaeDong; Jeong, Nak Cheon
    Journal of the American Chemical Society (2015), 137 (31), 10009-10015CODEN: JACSAT; ISSN:0002-7863. (American Chemical Society)
    Methylene chloride (MC) has been shown to perform the activation of metal-org. frameworks: this process can serve as an alternative "chem. route" for the activation that does not require applying heat. On the basis of Raman spectra, the authors propose a plausible mechanism for the chem. activation, in which the function of MC is possibly due to its coordination with the Cu2+ center and subsequent spontaneous decoordination. Using HKUST-1 film, it was further demonstrated that this chem. activation route is highly suitable for activating large-area MOF films.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2MXhtF2lt7%252FN&md5=3abbd20f8b083fc1bd8a155e2963959a
  16. 16
    Clark, R.; Tapily, K.; Yu, K. H.; Hakamata, T.; Consiglio, S.; O’Meara, D.; Wajda, C.; Smith, J.; Leusink, G. Perspective: New process technologies required for future devices and scaling. APL Mater. 2018, 6, 058203,  DOI: 10.1063/1.5026805
    Google Scholar
    16
    Perspective: New process technologies required for future devices and scaling
    Clark, R.; Tapily, K.; Yu, K.-H.; Hakamata, T.; Consiglio, S.; O'Meara, D.; Wajda, C.; Smith, J.; Leusink, G.
    APL Materials (2018), 6 (5), 058203/1-058203/12CODEN: AMPADS; ISSN:2166-532X. (American Institute of Physics)
    This paper presents an overview and perspective on processing technologies required for continued scaling of leading edge and emerging semiconductor devices. We introduce the main drivers and trends affecting future semiconductor device scaling and provide examples of emerging devices and architectures that may be implemented within the next 10-20 yr. We summarize multiple active areas of research to explain how future thin film deposition, etch, and patterning technologies can enable 3D (vertical) power, performance, area, and cost scaling. Emerging and new process technologies will be required to enable improved contacts, scaled and future devices and interconnects, monolithic 3D integration, and new computing architectures. These process technologies are explained and discussed with a focus on opportunities for continued improvement and innovation. (c) 2018 American Institute of Physics.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1cXhtVGisr7L&md5=23afc1e8855db73cb2a0d6e2f2017d77
  17. 17
    Tapily, K.; Jakes, J.; Stone, D.; Shrestha, P.; Gu, D.; Baumgart, H.; Elmustafa, A. Nanomechanical Properties of High-K Dielectrics Grown by Atomic Layer Deposition. ECS Trans. 2019, 11, 123– 130
    Google Scholar
    There is no corresponding record for this reference.
  18. 18
    Zhu, X.; Gu, D.; Li, Q.; Ioannou, D. E.; Baumgart, H.; Suehle, J. S.; Richter, C. A. Silicon nanowire NVM with high-k gate dielectric stack. Microelectron. Eng. 2009, 86, 1957– 1960,  DOI: 10.1016/j.mee.2009.03.095
    Google Scholar
    18
    Silicon nanowire NVM with high-k gate dielectric stack
    Zhu, Xiaoxiao; Gu, D.; Li, Qiliang; Ioannou, D. E.; Baumgart, H.; Suehle, J. S.; Richter, C. A.
    Microelectronic Engineering (2009), 86 (7-9), 1957-1960CODEN: MIENEF; ISSN:0167-9317. (Elsevier B.V.)
    Three flash memory cell structures with silicon nanowire channels and high-k dielec. stacks were fabricated with a "self-aligning" process and their characteristics are reported and compared in this paper: a Metal/SiO2/HfO2/SiO2/Si (MOHOS) cell with a SiO2 blocking layer and two Metal/Al2O3/HfO2/SiO2/Si (MAHOS) cells with Al2O3, all with HfO2 as the charge trapping layer. Compared to (control) planar cells, all three operate at higher speeds, attributed to the enhanced elec. field across the tunneling oxide surrounding the channel. The MAHOS cells (Al2O3 blocking layer) outperform the MOHOS cells (SiO2 blocking layer) and both have large memory window, fast operation speed, good endurance and retention.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD1MXmsFGrsLk%253D&md5=f445a4f5814fb35d1fb2dcc8063f30db
  19. 19
    Puurunen, R. L. Surface chemistry of atomic layer deposition: A case study for the trimethylaluminum/water process. J. Appl. Phys. 2005, 97, 1– 52,  DOI: 10.1063/1.1940727
    Google Scholar
    There is no corresponding record for this reference.
  20. 20
    Sundberg, P.; Karppinen, M. Organic and inorganic–organic thin film structures by molecular layer deposition: A review. Beilstein J. Nanotechnol. 2014, 5, 1104– 1136,  DOI: 10.3762/bjnano.5.123
    Google Scholar
    20
    Organic and inorganic-organic thin film structures by molecular layer deposition: a review
    Sundberg, Pia; Karppinen, Maarit
    Beilstein Journal of Nanotechnology (2014), 5 (), 1104-1136, 33 pp.CODEN: BJNEAH; ISSN:2190-4286. (Beilstein-Institut zur Foerderung der Chemischen Wissenschaften)
    The possibility to deposit purely org. and hybrid inorg.-org. materials in a way parallel to the state-of-the-art gas-phase deposition method of inorg. thin films, i.e., at. layer deposition (ALD), is currently experiencing a strongly growing interest. Like ALD in case of the inorgs., the emerging mol. layer deposition (MLD) technique for org. constituents can be employed to fabricate high-quality thin films and coatings with thickness and compn. control on the mol. scale, even on complex three-dimensional structures. Moreover, by combining the two techniques, ALD and MLD, fundamentally new types of inorg.-org. hybrid materials can be produced. In this review article, we first describe the basic concepts regarding the MLD and ALD/MLD processes, followed by a comprehensive review of the various precursors and precursor pairs so far employed in these processes. Finally, we discuss the first proof-of-concept expts. in which the newly developed MLD and ALD/MLD processes are exploited to fabricate novel multilayer and nanostructure architectures by combining different inorg., org. and hybrid material layers into on-demand designed mixts., superlattices and nanolaminates, and employing new innovative nanotemplates or post-deposition treatments to, e.g., selectively decomp. parts of the structure. Such layer-engineered and/or nanostructured hybrid materials with exciting combinations of functional properties hold great promise for high-end technol. applications.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2cXhs1ehtb7O&md5=11468e5290fe4593b537db5bc9d9f37a
  21. 21
    Han, S.; Mullins, C. B. Current Progress and Future Directions in Gas-Phase Metal-Organic Framework Thin-Film Growth. ChemSusChem 2020, 13, 5433– 5442,  DOI: 10.1002/cssc.202001504
    Google Scholar
    21
    Current Progress and Future Directions in Gas-Phase Metal-Organic Framework Thin-Film Growth
    Han, Sungmin; Mullins, C. Buddie
    ChemSusChem (2020), 13 (20), 5433-5442CODEN: CHEMIZ; ISSN:1864-5631. (Wiley-VCH Verlag GmbH & Co. KGaA)
    A review. Deposition of materials as a thin film is important for various applications, such as sensors, microelectronic devices, and membranes. There have been breakthroughs in gas-phase metal-org. framework (MOF) thin-film growth, which is more applicable to micro- and nanofabrication processes and also less harmful to the environment than solvent-based methods. Three different types of gas-phase MOF thin film deposition methods have been developed using chem. vapor deposition (CVD), at. layer deposition (ALD), and phys. vapor deposition (PVD)-CVD combined techniques. The CVD-based method basically converts metal oxide layers into MOF thin films by exposing the surface to ligand vapor. The ALD-based method allows growing MOF thin films following layer-by-layer (LBL) growth by sequentially exposing gas-phase metal and ligand precursors. The PVD-CVD method uses PVD for metal deposition and CVD for ligand deposition, which is similar to LBL growth. These gas-phase growth methods can broaden the use of MOFs in diverse areas. Herein, the current progress of gas-phase MOF thin film growth is discussed and future directions suggested.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BB3cXhslOqtrrE&md5=76236ae855b968a78b432d58da3974ae
  22. 22
    Meng, X. An overview of molecular layer deposition for organic and organic–inorganic hybrid materials: mechanisms, growth characteristics, and promising applications. J. Mater. Chem. A 2017, 5, 18326– 18378,  DOI: 10.1039/c7ta04449f
    Google Scholar
    22
    An overview of molecular layer deposition for organic and organic-inorganic hybrid materials: mechanisms, growth characteristics, and promising applications
    Meng, Xiangbo
    Journal of Materials Chemistry A: Materials for Energy and Sustainability (2017), 5 (35), 18326-18378CODEN: JMCAET; ISSN:2050-7496. (Royal Society of Chemistry)
    It was a strong desire for researchers to control material growth at the mol. and at. levels. Mol. and at. layer deposition (MLD and ALD) are two such techniques. In comparison to a huge amt. of studies invested on ALD, the research on MLD is still relatively limited due to the difficulty in finding suitable coupling precursors, but the recently successful applications of MLD are encouraging in many areas such as surface engineering, new energies, and catalysis. In order to further stimulate more research enthusiasm and educate beginners, we contribute this thorough survey on the progress of MLD. This review is a comprehensive account of MLD processes for org. and org.-inorg. materials, covering precursors, surface chem., growth characteristics, film properties, and promising applications. The work provides a complete summary of over 80 MLD processes for growing over 20 types of pure polymeric and metal-based hybrid polymeric materials. Given their similarities in mechanisms, we made a comparative description between ALD and MLD, and discussed the uncountable possibilities to combine both ALD and MLD for advanced materials with desirable properties. To feature and highlight the significance of MLD, this review specially gives some detailed discussions on MLD's applications in several important areas, including novel nanostructured materials, surface engineering, new energies (i.e., batteries, supercapacitors, solar cells, and water splitting), catalysis, and rewritable data storage. With this work, we expect to boost research interest and attempts at advanced materials using MLD as well as ALD.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2sXht1ektbzM&md5=8d28ef8126a56c93ee8835a80a143899
  23. 23
    Svärd, L.; Putkonen, M.; Kenttä, E.; Sajavaara, T.; Krahl, F.; Karppinen, M.; Van de Kerckhove, K.; Detavernier, C.; Simell, P. Low-Temperature Molecular Layer Deposition Using Monofunctional Aromatic Precursors and Ozone-Based Ring-Opening Reactions. Langmuir 2017, 33, 9657– 9665
    Google Scholar
    23
    Low-Temperature Molecular Layer Deposition Using Monofunctional Aromatic Precursors and Ozone-Based Ring-Opening Reactions
    Svard, Laura; Putkonen, Matti; Kentta, Eija; Sajavaara, Timo; Krahl, Fabian; Karppinen, Maarit; Van de Kerckhove, Kevin; Detavernier, Christophe; Simell, Pekka
    Langmuir (2017), 33 (38), 9657-9665CODEN: LANGD5; ISSN:0743-7463. (American Chemical Society)
    Mol. layer deposition (MLD) is an increasingly used deposition technique for producing thin coatings consisting of purely org. or hybrid inorg.-org. materials. When org. materials are prepd., low deposition temps. are often required to avoid decompn., thus causing problems with low vapor pressure precursors. Monofunctional compds. have higher vapor pressures than traditional bi- or trifunctional MLD precursors, but do not offer the required functional groups for continuing the MLD growth in subsequent deposition cycles. The authors used high vapor pressure monofunctional arom. precursors in combination with ozone-triggered ring-opening reactions to achieve sustained sequential growth. MLD depositions were carried out by using three different arom. precursors in an ABC sequence, namely with TMA + phenol + O3, TMA + 3-(trifluoromethyl)phenol + O3, and TMA + 2-fluoro-4-(trifluoromethyl)benzaldehyde + O3. The effect of hydrogen peroxide as a fourth step was evaluated for all studied processes resulting in a four-precursor ABCD sequence. According to the characterization results by ellipsometry, IR spectroscopy, and X-ray reflectivity, self-limiting MLD processes could be obtained between 75 and 150 °C with each of the three arom. precursors. In all cases, the GPC (growth per cycle) decreased with increasing temp. In situ IR spectroscopy indicated that ring-opening reactions occurred in each ABC sequence. Compositional anal. using time-of-flight elastic recoil detection indicated that fluorine could be incorporated into the film when 3-(trifluoromethyl)phenol and 2-fluoro-4-(trifluoromethyl)benzaldehyde were used as precursors.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2sXhtlyhsLrK&md5=253484c3d41a5d2eb83cec26eaf64a82
  24. 24
    George, S. M.; Yoon, B.; Dameron, A. A. Surface Chemistry for Molecular Layer Deposition of Organic and Hybrid Organic–Inorganic Polymers. Acc. Chem. Res. 2009, 42, 498– 508,  DOI: 10.1021/ar800105q
    Google Scholar
    24
    Surface Chemistry for Molecular Layer Deposition of Organic and Hybrid Organic-Inorganic Polymers
    George, Steven M.; Yoon, Byunghoon; Dameron, Arrelaine A.
    Accounts of Chemical Research (2009), 42 (4), 498-508CODEN: ACHRE4; ISSN:0001-4842. (American Chemical Society)
    A review. The fabrication of many devices in modern technol. requires techniques for growing thin films. As devices miniaturize, manufacturers will need to control thin film growth at the at. level. Because many devices have challenging morphologies, thin films must be able to coat conformally on structures with high aspect ratios. Techniques based on at. layer deposition (ALD), a special type of chem. vapor deposition, allow for the growth of ultra-thin and conformal films of inorg. materials using sequential, self-limiting reactions. Mol. layer deposition (MLD) methods extend this strategy to include org. and hybrid org.-inorg. polymeric materials. An overview of the surface chem. for MLD of org. and hybrid org.-inorg. polymers and a variety of surface chem. strategies for growing polymer thin films are outlined. Previously, surface chem. for MLD of polyamides and polyimides has used two-step AB reaction cycles using homo-bifunctional monomers. However, these monomers can react twice and eliminate active sites on the growing polymer surface. To avoid this problem, alternative precursors are used for MLD based on hetero-bifunctional monomers and ring-opening reactions. Surface activation or protected chem. functional groups can also be used. Combinations of monomers for ALD and MLD allow prepn. of hybrid org.-inorg. polymers that should display interesting properties. For example, using trimethylaluminum (TMA) and various diols, MLD of alucone org.-inorg. polymers was achieved. The chem. and phys. properties of these org.-inorg. polymers can be changed by varying the org. constituent in the diol or blending the alucone MLD films with purely inorg. ALD films to build a nanocomposite or nanolaminate. The combination of ALD and MLD reactants enlarges the no. of possible sequential self-limiting surface reactions for film growth. Extensions to three-step ABC reaction cycles also offer many advantages to avoid the use of homo-bifunctional reactants and incorporate new functionality in the thin film. The advances in ALD have helped technol. development in many areas, including semiconductor processing and magnetic disk-drive manufg. The advances in MLD are expected to advance innovations in polymeric thin-film products. Although there are remaining challenges, effective surface chem. strategies are being developed for MLD that offer the opportunity for future advances in materials and device fabrication.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD1MXisV2nt7s%253D&md5=1ca4399397f85e7d4f40afd7dfc6c800
  25. 25
    Sønsteby, H. H.; Yanguas-Gil, A.; Elam, J. W. Consistency and reproducibility in atomic layer deposition. J. Vac. Sci. Technol., A 2020, 38, 020804
    Google Scholar
    There is no corresponding record for this reference.
  26. 26
    Stassen, I.; Styles, M.; Grenci, G.; Gorp, V.; Vanderlinden, W.; Feyter, D.; Falcaro, P.; Vos, D. D.; Vereecken, P.; Ameloot, R. Chemical vapour deposition of zeolitic imidazolate framework thin films. Nat. Mater. 2016, 15, 304– 310,  DOI: 10.1038/nmat4509
    Google Scholar
    26
    Chemical vapor deposition of zeolitic imidazolate framework thin films
    Stassen, Ivo; Styles, Mark; Grenci, Gianluca; Gorp, Hans Van; Vanderlinden, Willem; Feyter, Steven De; Falcaro, Paolo; Vos, Dirk De; Vereecken, Philippe; Ameloot, Rob
    Nature Materials (2016), 15 (3), 304-310CODEN: NMAACR; ISSN:1476-1122. (Nature Publishing Group)
    A chem. vapor deposition process (MOF-CVD) that enables high-quality films of ZIF-8, a prototypical MOF material, with a uniform and controlled thickness, even on high-aspect-ratio features, is reported. The authors demonstrate how MOF-CVD enables previously inaccessible routes such as lift-off patterning and depositing MOF films on fragile features. The compatibility of MOF-CVD with existing infrastructure, both in research and prodn. facilities, will greatly facilitate MOF integration in microelectronics. MOF-CVD is the first vapor-phase deposition method for any type of microporous cryst. network solid and marks a milestone in processing such materials.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2MXitVWqtrrK&md5=10554458c52c84c69e923e31c479dbf4
  27. 27
    Ahvenniemi, E.; Karppinen, M. Atomic/molecular layer deposition: a direct gas-phase route to crystalline metal–organic framework thin films. Chem. Commun. 2016, 52, 1139– 1142,  DOI: 10.1039/c5cc08538a
    Google Scholar
    27
    Atomic/molecular layer deposition: a direct gas-phase route to crystalline metal-organic framework thin films
    Ahvenniemi, E.; Karppinen, M.
    Chemical Communications (Cambridge, United Kingdom) (2016), 52 (6), 1139-1142CODEN: CHCOFS; ISSN:1359-7345. (Royal Society of Chemistry)
    Atomic/mol. layer deposition offers the authors an elegant way of fabricating cryst. copper(II)terephthalate metal-org. framework (MOF) thin films on various substrate surfaces. The films are grown from two gaseous precursors with a digital at./mol. level control for the film thickness under relatively mild conditions in a simple and fast 1-step process.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2MXhvVGnurvL&md5=4e85fd1ee2b7e6299ca5cc2323b7f8e9
  28. 28
    Ahvenniemi, E.; Karppinen, M. In Situ Atomic/Molecular Layer-by-Layer Deposition of Inorganic–Organic Coordination Network Thin Films from Gaseous Precursors. Chem. Mater. 2016, 28, 6260– 6265,  DOI: 10.1021/acs.chemmater.6b02496
    Google Scholar
    28
    In Situ Atomic/Molecular Layer-by-Layer Deposition of Inorganic-Organic Coordination Network Thin Films from Gaseous Precursors
    Ahvenniemi, Esko; Karppinen, Maarit
    Chemistry of Materials (2016), 28 (17), 6260-6265CODEN: CMATEX; ISSN:0897-4756. (American Chemical Society)
    Cryst. inorg.-org. coordination network materials possess a property palette highly attractive for a no. of frontier applications. In many prospective applications of these materials, high-quality thin films would be required. Gas-phase thin-film techniques could potentially provide a no. of advantages over the current liq.-phase techniques for depositing such state-of-the-art hybrid thin films. The strongly emerging at./mol. layer deposition (ALD/MLD) technique in particular enables the rational fabrication of inorg.-org. thin films in a digital at./mol. layer-by-layer manner through successive gas-to-surface reactions of inorg. and org. precursors, but the resultant films have been amorphous. Here, we demonstrate the in situ ALD/MLD growth of well-cryst. calcium terephthalate (Ca-TP) coordination network thin films in a wide deposition temp. range. We moreover investigate the water absorption/desorption characteristics of the films and report attractive mech. properties for both the dry and water-intercalated films.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC28XhsVSgur7P&md5=e8a5b30b1a76c5cb61bbcaaaa20831f2
  29. 29
    Lausund, K. B.; Nilsen, O. All-gas-phase synthesis of UiO-66 through modulated atomic layer deposition. Nat. Commun. 2016, 7, 13578,  DOI: 10.1038/ncomms13578
    Google Scholar
    29
    All-gas-phase synthesis of UiO-66 through modulated atomic layer deposition
    Lausund, Kristian Blindheim; Nilsen, Ola
    Nature Communications (2016), 7 (), 13578CODEN: NCAOBW; ISSN:2041-1723. (Nature Publishing Group)
    Thin films of stable metal-org. frameworks (MOFs) such as UiO-66 have enormous application potential, for instance in microelectronics. However, all-gas-phase deposition techniques are currently not available for such MOFs. We here report on thin-film deposition of the thermally and chem. stable UiO-66 in an all-gas-phase process by the aid of at. layer deposition (ALD). Sequential reactions of ZrCl4 and 1,4-benzenedicarboxylic acid produce amorphous org.-inorg. hybrid films that are subsequently crystd. to the UiO-66 structure by treatment in acetic acid vapor. We also introduce a new approach to control the stoichiometry between metal clusters and org. linkers by modulation of the ALD growth with addnl. acetic acid pulses. An all-gas-phase synthesis technique for UiO-66 could enable implementations in microelectronics that are not compatible with solvothermal synthesis. Since this technique is ALD-based, it could also give enhanced thickness control and the possibility to coat irregular substrates with high aspect ratios.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC28XitFSns77M&md5=7ec72beaa1e506bba57b17476c62ec10
  30. 30
    Multia, J.; Karppinen, M. Atomic/Molecular Layer Deposition for Designer’s Functional Metal–Organic Materials. Adv. Mater. Interfaces 2022, 9, 2200210,  DOI: 10.1002/admi.202200210
    Google Scholar
    30
    Atomic/Molecular Layer Deposition for Designer's Functional Metal-Organic Materials
    Multia, Jenna; Karppinen, Maarit
    Advanced Materials Interfaces (2022), 9 (15), 2200210CODEN: AMIDD2; ISSN:2196-7350. (Wiley-VCH Verlag GmbH & Co. KGaA)
    Atomic layer deposition (ALD) for high-quality conformal inorg. thin films is one of the cornerstones of modern microelectronics, while mol. layer deposition (MLD) is its less-exploited counterpart for purely org. thin films. Currently, the hybrid of these two techniques, i.e., ALD/MLD, is strongly emerging as a state-of-the-art gas-phase route for designer's metal-org. thin films, e.g., for the next-generation energy technologies. The ALD/MLD literature comprises nearly 300 original journal papers covering most of the alkali and alk. earth metals, 3d transition metals, and lanthanides as the metal component and a variety of aliph., arom., and natural org. components. Some of these ALD/MLD processes yield in situ cryst. coordination-polymer- or metal-org.-framework-like structures. Another attractive aspect is that many of the metal-orgs. realized through ALD/MLD are fundamentally new materials, and even unaccessible through conventional synthesis. Here, the current state of research in the field is presented, by i) providing a comprehensive account of the ALD/MLD processes so far developed, ii) addressing the constraints/possibilities for growing in situ cryst. metal-org. films, iii) highlighting some intriguing ALD/MLD materials and their application potential, and iv) making a brief outlook to the future perspectives and challenges in the field.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BB38XhtV2hur3P&md5=f1bb8758dcdb66863c84ef136397e97b
  31. 31
    Stassen, I.; De Vos, D.; Ameloot, R. Vapor-Phase Deposition and Modification of Metal–Organic Frameworks: State-of-the-Art and Future Directions. Chem. - Eur. J. 2016, 22, 14452– 14460,  DOI: 10.1002/chem.201601921
    Google Scholar
    31
    Vapor-Phase Deposition and Modification of Metal-Organic Frameworks: State-of-the-Art and Future Directions
    Stassen, Ivo; De Vos, Dirk; Ameloot, Rob
    Chemistry - A European Journal (2016), 22 (41), 14452-14460CODEN: CEUJED; ISSN:0947-6539. (Wiley-VCH Verlag GmbH & Co. KGaA)
    A review. Materials processing, and thin-film deposition in particular, is decisive in the implementation of functional materials in industry and real-world applications. Vapor processing of materials plays a central role in manufg., esp. in electronics. Metal-org. frameworks (MOFs) are a class of nanoporous cryst. materials on the brink of breakthrough in many application areas. Vapor deposition of MOF thin films will facilitate their implementation in micro- and nanofabrication research and industries. In addn., vapor-solid modification can be used for postsynthetic tailoring of MOF properties. The authors review the recent progress in vapor processing of MOFs, summarize the underpinning chem. and principles, and highlight promising directions for future research.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC28Xht1ygsbnJ&md5=4b44a79c5fe752eea4f092aba1d259f4
  32. 32
    Stassin, T.; Rodríguez-Hermida, S.; Schrode, B.; Cruz, A. J.; Carraro, F.; Kravchenko, D.; Creemers, V.; Stassen, I.; Hauffman, T.; De Vos, D.; Falcaro, P.; Resel, R.; Ameloot, R. Vapour-phase deposition of oriented copper dicarboxylate metal–organic framework thin films. Chem. Commun. 2019, 55, 10056– 10059,  DOI: 10.1039/c9cc05161a
    Google Scholar
    32
    Vapour-phase deposition of oriented copper dicarboxylate metal-organic framework thin films
    Stassin, Timothee; Rodriguez-Hermida, Sabina; Schrode, Benedikt; Cruz, Alexander John; Carraro, Francesco; Kravchenko, Dmitry; Creemers, Vincent; Stassen, Ivo; Hauffman, Tom; De Vos, Dirk; Falcaro, Paolo; Resel, Roland; Ameloot, Rob
    Chemical Communications (Cambridge, United Kingdom) (2019), 55 (68), 10056-10059CODEN: CHCOFS; ISSN:1359-7345. (Royal Society of Chemistry)
    Copper dicarboxylate metal-org. framework films are deposited via chem. vapor deposition. Uniform films of CuBDC and CuCDC with an out-of-plane orientation and accessible porosity are obtained from the reaction of Cu and CuO with vaporized dicarboxylic acid linkers.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1MXhsVChtLjE&md5=e9fd65cebe4385d8652e0534b7c63a97
  33. 33
    Stassin, T.; Stassen, I.; Marreiros, J.; Cruz, A. J.; Verbeke, R.; Tu, M.; Reinsch, H.; Dickmann, M.; Egger, W.; Vankelecom, I. F. J.; De Vos, D. E.; Ameloot, R. Solvent-Free Powder Synthesis and MOF-CVD Thin Films of the Large-Pore Metal–Organic Framework MAF-6. Chem. Mater. 2020, 32, 1784– 1793,  DOI: 10.1021/acs.chemmater.9b03807
    Google Scholar
    33
    Solvent-Free Powder Synthesis and MOF-CVD Thin Films of the Large-Pore Metal-Organic Framework MAF-6
    Stassin, Timothee; Stassen, Ivo; Marreiros, Joao; Cruz, Alexander John; Verbeke, Rhea; Tu, Min; Reinsch, Helge; Dickmann, Marcel; Egger, Werner; Vankelecom, Ivo F. J.; De Vos, Dirk E.; Ameloot, Rob
    Chemistry of Materials (2020), 32 (5), 1784-1793CODEN: CMATEX; ISSN:0897-4756. (American Chemical Society)
    A simple solvent- and catalyst-free method is presented for the synthesis of the large-pore metal-org. framework (MOF) MAF-6 (RHO-Zn(eIm)2) based on the reaction of ZnO with 2-ethylimidazole vapor at temps. ≤ 100°C. By translating this method to a chem. vapor deposition (CVD) protocol, cryst. films of a large-pore material could be deposited for the first time entirely from the vapor phase. A combination of PALS and Kr physisorption measurements confirmed the porosity of these MOF-CVD films and the size of the MAF-6 supercages (diam. ∼2 nm), in close agreement with powder data and calcns. MAF-6 powders and films were further characterized by XRD, TGA, SEM, FTIR, PDF and EXAFS. The exceptional uptake capacity of MAF-6 in comparison to ZIF-8 is demonstrated by vapor-phase loading of a mol. larger than the ZIF-8 windows.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BB3cXhsFKisbw%253D&md5=5030e1422fc43ff76fddeaefd2dc2a76
  34. 34
    Fichtner, J.; Wu, Y.; Hitzenberger, J.; Drewello, T.; Bachmann, J. Molecular Layer Deposition from Dissolved Precursors. ECS J. Solid State Sci. Technol. 2017, 6, N171– N175,  DOI: 10.1149/2.0291709jss
    Google Scholar
    34
    Molecular Layer Deposition from Dissolved Precursors
    Fichtner, J.; Wu, Y.; Hitzenberger, J.; Drewello, T.; Bachmann, J.
    ECS Journal of Solid State Science and Technology (2017), 6 (9), N171-N175CODEN: EJSSBG; ISSN:2162-8769. (Electrochemical Society)
    We present a procedure for growing thin films of an org. polyamid material based on a cyclic repetition of two consecutive, complementary, self-limiting surface reactions. The mol. compds. that react with the surface are dissolved in an org. solvent. This new method exemplifies how at. layer deposition (ALD) and mol. layer deposition (MLD) can benefit from being transferred from the gas phase to the liq. phase, given that a broad variety of advantageous reagents are only available in dissolved form.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2sXhsFOjt7%252FN&md5=78f0c95b5bd097a4dceb8849ce0c0e34
  35. 35
    Koch, V. M.; Barr, M. K. S.; Büttner, P.; Mínguez-Bacho, I.; Döhler, D.; Winzer, B.; Reinhardt, E.; Segets, D.; Bachmann, J. A solution-based ALD route towards (CH3NH3)(PbI3) perovskite via lead sulfide films. J. Mater. Chem. A 2019, 7, 25112– 25119,  DOI: 10.1039/c9ta09715e
    Google Scholar
    35
    A solution-based ALD route towards (CH3NH3)(PbI3) perovskite via lead sulfide films
    Koch, Vanessa M.; Barr, Maissa K. S.; Buettner, Pascal; Minguez-Bacho, Ignacio; Doehler, Dirk; Winzer, Bettina; Reinhardt, Elisabeth; Segets, Doris; Bachmann, Julien
    Journal of Materials Chemistry A: Materials for Energy and Sustainability (2019), 7 (43), 25112-25119CODEN: JMCAET; ISSN:2050-7496. (Royal Society of Chemistry)
    We present a procedure to grow thin films of lead sulfide (PbS) with 'soln. Atomic Layer Deposition' (sALD), a technique which transfers the principles of ALD from the gas phase (gALD) to liq. processing. PbS thin films are successfully deposited on planar and porous substrates with a procedure that exhibits the unique ALD characteristics of self-limiting surface chem. and linear growth at room temp. The polycryst. p-type PbS films are stoichiometric and pure. They are converted to the hybrid perovskite methylammonium iodoplumbate (methylammonium lead iodide, MAPI, CH3NH3PbI3) by annealing to 150 °C in the presence of vapors from methylammonium iodide (MAI).
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1MXitVaksr%252FK&md5=ac6254f258f05eed00f4d7d47c09abd3
  36. 36
    Wu, Y.; Döhler, D.; Barr, M.; Oks, E.; Wolf, M.; Santinacci, L.; Bachmann, J. Atomic Layer Deposition from Dissolved Precursors. Nano Lett. 2015, 15, 6379– 6385,  DOI: 10.1021/acs.nanolett.5b01424
    Google Scholar
    36
    Atomic Layer Deposition from Dissolved Precursors
    Wu, Yanlin; Doehler, Dirk; Barr, Maissa; Oks, Elina; Wolf, Marc; Santinacci, Lionel; Bachmann, Julien
    Nano Letters (2015), 15 (10), 6379-6385CODEN: NALEFD; ISSN:1530-6984. (American Chemical Society)
    We establish a novel thin film deposition technique by transferring the principles of at. layer deposition (ALD) known with gaseous precursors toward precursors dissolved in a liq. An established ALD reaction behaves similarly when performed from solns. "Soln. ALD" (sALD) can coat deep pores in a conformal manner. sALD offers novel opportunities by overcoming the need for volatile and thermally robust precursors. We establish a MgO sALD procedure based on the hydrolysis of a Grignard reagent.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2MXhs1akt7fL&md5=f3e7148e495a79f0b51494eaeee13bc9
  37. 37
    Liu, J.; Lukose, B.; Shekhah, O.; Arslan, H. K.; Weidler, P.; Gliemann, H.; Bräse, S.; Grosjean, S.; Godt, A.; Feng, X.; Müllen, K.; Magdau, I.-B.; Heine, T.; Wöll, C. A novel series of isoreticular metal organic frameworks: realizing metastable structures by liquid phase epitaxy. Sci. Rep. 2012, 2, 921,  DOI: 10.1038/srep00921
    Google Scholar
    37
    A novel series of isoreticular metal organic frameworks: realizing metastable structures by liquid phase epitaxy
    Liu, Jinxuan; Lukose, Binit; Shekhah, Osama; Arslan, Hasan Kemal; Weidler, Peter; Gliemann, Hartmut; Brase, Stefan; Grosjean, Sylvain; Godt, Adelheid; Feng, Xinliang; Muellen, Klaus; Magdau, Ioan-Bogdan; Heine, Thomas; Woell, Christof
    Scientific Reports (2012), 2 (), srep00921, 5 pp.CODEN: SRCEC3; ISSN:2045-2322. (Nature Publishing Group)
    A novel class of metal org. frameworks (MOFs) was synthesized from Cu2(O2CMe)4·H2O and dicarboxylic acids using liq. phase epitaxy (LPE). The SURMOF-2 isoreticular series exhibits P4 symmetry, for the longest linker a channel-size of 3 × 3 nm2 was obtained, one of the largest values reported for any MOF so far. High quality, ab-initio electronic structure calcns. confirm the stability of a regular packing of (Cu++)2- carboxylate paddle-wheel planes with P4 symmetry and reveal, that the SURMOF-2 structures are in fact metastable, with a fairly large activation barrier for the transition to the bulk MOF-2 structures exhibiting a lower, 2-fold (P2 or C2) symmetry. The theor. calcns. also allow identifying the mechanism for the low-temp. epitaxial growth process and to explain, why a synthesis of this highly interesting, new class of high-symmetry, metastable MOFs is not possible using the conventional solvothermal process.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3sXmtVWlsw%253D%253D&md5=c3ab963fe3ee722be3cba530edd58388
  38. 38
    Shekhah, S.; Wang, H.; Kowarik, S.; Schreiber, F.; Paulus, M.; Tolan, M.; Sternemann, C.; Evers, F.; Evers, D.; Zacher, R. A.; Fischer, C.; Wöll, C. Step-by-step route for the synthesis of metal– organic frameworks. J. Am. Chem. Soc. 2007, 129, 15118– 9,  DOI: 10.1021/ja076210u
    Google Scholar
    38
    Step-by-Step Route for the Synthesis of Metal-Organic Frameworks
    Shekhah, Osama; Wang, Hui; Kowarik, Stefan; Schreiber, Frank; Paulus, Michael; Tolan, Metin; Sternemann, Christian; Evers, Florian; Zacher, Denise; Fischer, Roland A.; Woell, Christof
    Journal of the American Chemical Society (2007), 129 (49), 15118-15119CODEN: JACSAT; ISSN:0002-7863. (American Chemical Society)
    Using a novel layer-by-layer approach the authors have deposited metal-org. open frameworks (MOFs), [Cu3(BTC)2(H2O)n], based on 1,3,5-benzenetricarboxylic acid (H3BTC) and Cu(II)-ions on a COOH-terminated org. surface. The deposited layers were characterized using a no. of surface anal. techniques. XRD measurements show that the MOFs deposited using this method have the same bulk structure of HKUST-1.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD2sXhtlWmu7jI&md5=46beafc40035a456b09930a813cf7f44
  39. 39
    Arslan, H. K.; Shekhah, O.; Wohlgemuth, J.; Franzreb, M.; Fischer, R. A.; Wöll, C. High-Throughput Fabrication of Uniform and Homogenous MOF Coatings. Adv. Funct. Mater. 2011, 21, 4228– 4231,  DOI: 10.1002/adfm.201101592
    Google Scholar
    39
    High-Throughput Fabrication of Uniform and Homogeneous MOF Coatings
    Arslan, Hasan K.; Shekhah, Osama; Wohlgemuth, Jonas; Franzreb, Matthias; Fischer, Roland A.; Woell, Christof
    Advanced Functional Materials (2011), 21 (22), 4228-4231CODEN: AFMDC6; ISSN:1616-301X. (Wiley-VCH Verlag GmbH & Co. KGaA)
    We describe a novel method to produce monolithic, oriented, cryst. and highly porous coatings on solid substrates. By adopting the recently described liq.-phase epitaxy (LPE) process developed to grow metal-org. framework coatings (MOFs) on modified Au-substrates to the spray method, we have prepd. thick (μm) layers of several MOF types on modified Au-substrates, including HKUST-I and layer-pillar MOFs. The spray method not only allows such SURMOFs to be grown much faster than with the LPE-process but the dependence of layer thickness on the no. of immersion cycles also provides valuable insights into the mechanism governing the layer-by-layer MOF formation process.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3MXhtFCntrfL&md5=6b86cfdae37cbbf2a880adb49439c357
  40. 40
    Arslan, H. K.; Shekhah, O.; Wieland, D. C. F.; Paulus, M.; Sternemann, C.; Schroer, M. A.; Tiemeyer, S.; Tolan, M.; Fischer, R. A.; Wöll, C. Intercalation in layered metal–organic frameworks: reversible inclusion of an extended π-system. J. Am. Chem. Soc. 2011, 133, 8158– 8161,  DOI: 10.1021/ja2037996
    Google Scholar
    40
    Intercalation in Layered Metal-Organic Frameworks: Reversible Inclusion of an Extended π-System
    Arslan, Hasan K.; Shekhah, Osama; Wieland, D. C. Florian; Paulus, Michael; Sternemann, Christian; Schroer, Martin A.; Tiemeyer, Sebastian; Tolan, Metin; Fischer, Roland A.; Woll, Christof
    Journal of the American Chemical Society (2011), 133 (21), 8158-8161CODEN: JACSAT; ISSN:0002-7863. (American Chemical Society)
    The authors report the synthesis of layered [Zn2(bdc)2(H2O)2] and [Cu2(bdc)2(H2O)2] (bdc = 1,4-benzenedicarboxylate) metal-org. frameworks (MOF) carried out using the LPE approach employing self-assembled monolayer (SAM) modified Au-substrates. The authors obtain Cu and Zn MOF-2 structures, which have not yet been obtained using conventional, solvothermal synthesis methods. The 2-dimensional Cu2+ dimer paddle wheel planes characteristic for the MOF are strictly planar, with the planes oriented perpendicular to the substrate. Intercalation of an org. dye, DXP (N,N'-bis(2,6-dimethylphenyl)-3,4:9,10-perylentetracarboxylic diimide) leads to a reversible tilting of the planes, demonstrating the huge potential of these surface-anchored MOFs for the intercalation of large, planar mols.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3MXlvVSks7o%253D&md5=730e9689a9d5cce7dba8bdc96026f2ac
  41. 41
    Lee, J.-C.; Kim, J.-O.; Lee, H.-J.; Shin, B.; Park, S. Meniscus-Guided Control of Supersaturation for the Crystallization of High Quality Metal Organic Framework Thin Films. Chem. Mater. 2019, 31, 7377– 7385,  DOI: 10.1021/acs.chemmater.9b01996
    Google Scholar
    41
    Meniscus-Guided Control of Supersaturation for the Crystallization of High Quality Metal Organic Framework Thin Films
    Lee, Jeong-Chan; Kim, Jin-Oh; Lee, Ho-Jun; Shin, Byungha; Park, Steve
    Chemistry of Materials (2019), 31 (18), 7377-7385CODEN: CMATEX; ISSN:0897-4756. (American Chemical Society)
    Herein, meniscus-guided crystn. is introduced as a means to grow high quality metal org. framework (MOF) thin films. A meniscus was formed between a target substrate and a coating blade, and by adjusting various parameters such as substrate temp. and coating speed, supersatn. was precisely controlled, through which the crystn. process was finely tuned. Consequently, a densely packed intergrown MOF thin film with thickness tunability down to 450 nm was demonstrated. The individual crystals exhibited monodispersity in size. Interestingly, the use of a microstructured coating blade resulted in the change of crystal shape, attributed to the supersatn.-induced kinetically driven crystn. process. Our film growth process is large-area scalable, uses a miniscule amt. of soln., and has substrate versatility. Such an insight and demonstration of MOF thin-film growth via meniscus-guided crystn. will be highly useful for the development of various MOF thin-film-based devices in the future.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1MXhslWmsrbL&md5=c5cd6a8f1acbd29442776f6507662ed5
  42. 42
    Mandemaker, L. D. B.; Filez, M.; Delen, G.; Tan, H.; Zhang, X.; Lohse, D.; Weckhuysen, B. M. Time-Resolved In Situ Liquid-Phase Atomic Force Microscopy and Infrared Nanospectroscopy during the Formation of Metal–Organic Framework Thin Films. J. Phys. Chem. Lett. 2018, 9, 1838– 1844,  DOI: 10.1021/acs.jpclett.8b00203
    Google Scholar
    42
    Time-Resolved In Situ Liquid-Phase Atomic Force Microscopy and Infrared Nanospectroscopy during the Formation of Metal-Organic Framework Thin Films
    Mandemaker, Laurens D. B.; Filez, Matthias; Delen, Guusje; Tan, Huanshu; Zhang, Xuehua; Lohse, Detlef; Weckhuysen, Bert M.
    Journal of Physical Chemistry Letters (2018), 9 (8), 1838-1844CODEN: JPCLCD; ISSN:1948-7185. (American Chemical Society)
    Metal-org. framework (MOF) thin films show unmatched promise as smart membranes and photocatalytic coatings. However, their nucleation and growth resulting from intricate mol. assembly processes are not well understood yet are crucial to control the thin film properties. Here, we directly observe the nucleation and growth behavior of HKUST-1 thin films by real-time in situ AFM at different temps. in a Cu-BTC soln. In combination with ex situ IR (nano)spectroscopy, synthesis at 25 °C reveals initial nucleation of rapidly growing HKUST-1 islands surrounded by a continuously nucleating but slowly growing HKUST-1 carpet. Monitoring at 13 and 50 °C shows the strong impact of temp. on thin film formation, resulting in (partial) nucleation and growth inhibition. The nucleation and growth mechanisms as well as their kinetics provide insights to aid in future rational design of MOF thin films.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1cXmt1Cnsr0%253D&md5=66b5c6f95db3bcef902db207e4745882
  43. 43
    Haraguchi, T.; Otsubo, K.; Kitagawa, H. Emergence of Surface- and Interface-Induced Structures and Properties in Metal–Organic Framework Thin Films. Eur. J. Inorg. Chem. 2018, 2018, 1697– 1706,  DOI: 10.1002/ejic.201701234
    Google Scholar
    43
    Emergence of Surface- and Interface-Induced Structures and Properties in Metal-Organic Framework Thin Films
    Haraguchi, Tomoyuki; Otsubo, Kazuya; Kitagawa, Hiroshi
    European Journal of Inorganic Chemistry (2018), 2018 (16), 1697-1706CODEN: EJICFO; ISSN:1434-1948. (Wiley-VCH Verlag GmbH & Co. KGaA)
    A review. Metal-org. frameworks (MOFs) are of particular interest to researchers because of their structural diversity and variety of properties. MOF thin films have been intensively investigated for potential applications such as membranes, gas sensors, catalysts, etc. Although most MOF thin films have almost the same structure and properties as their bulk, some MOF thin films show remarkable structural changes and hidden properties that are not obsd. in the bulk. These phenomena would be induced by the surface and the interface. Recent improvements in thin-film fabrication methods enabled us to construct MOF thin films and discuss the properties based on the structure, thickness and cryst. orientation in detail. This microreview describes and discusses the fascinating nature of MOF thin films originating from surface/interface. This paper is expected to help with the construction of a research strategy for MOF thin films to obtain hidden structures and properties of MOFs that are not obsd. in their bulk.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1cXivFOjs7Y%253D&md5=6bc2aecf1bf2e5c5778e16d1007f130e
  44. 44
    Redel, E.; Wang, Z.; Walheim, S.; Liu, J.; Gliemann, H.; Wöll, C. On the dielectric and optical properties of surface-anchored metal-organic frameworks: A study on epitaxially grown thin films. Appl. Phys. Lett. 2013, 103, 1– 5,  DOI: 10.1063/1.4819836
    Google Scholar
    There is no corresponding record for this reference.
  45. 45
    Puurunen, R. Growth Per Cycle in Atomic Layer Deposition: A Theoretical Model. Chem. Vap. Deposition 2003, 9, 249– 257,  DOI: 10.1002/cvde.200306265
    Google Scholar
    45
    Growth per cycle in atomic layer deposition: A theoretical model
    Puurunen, Riikka L.
    Chemical Vapor Deposition (2003), 9 (5), 249-257CODEN: CVDEFX; ISSN:0948-1907. (Wiley-VCH Verlag GmbH & Co. KGaA)
    At. layer deposition (ALD) was used in advanced applications where thin layers of materials with precise thickness down to the nanometer scale are needed. Growth of materials by ALD takes place through repeating the sep., satg. reactions of at least two gaseous reactants with a solid substrate. When surface satn. is systematically used, the growth obtained per ALD reaction cycle is a well-defined quantity that depends on (i) the reactants used, (ii) the ALD processing temp., and (iii) sometimes the substrate material. A model is derived to describe the growth per cycle in ALD as a function of the chem. of the growth when compds. were used as reactants. Two main types of chemisorption may occur: (i) ligand exchange reaction of the MLn reactant with surface a groups, where ligands are removed from the surface as gaseous aL, and (ii) dissocn. or assocn., where all parts of the MLn reactant are attached to the surface. A simple math. model based on the mass balance of chemisorption relates the growth per cycle to the size of the MLn reactant and the chemisorption mechanisms involved. Steric hindrance of the ligands causes satn. of chemisorption if a limited no. of bonding sites does not cause it. Because of the steric hindrance, the growth per cycle remains less than a monolayer. The applicability of the model is illustrated through several theor. examples.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD3sXovFCkurs%253D&md5=8c1c3c359c5563692fcfa586b89484be
  46. 46
    Li, X.; Zhou, H.; Qi, F.; Niu, X.; Xu, X.; Qiu, F.; He, Y.; Pan, J.; NiPan, L. Three hidden talents in one framework: a terephthalic acid-coordinated cupric metal–organic framework with cascade cysteine oxidase- and peroxidase-mimicking activities and stimulus-responsive fluorescence for cysteine sensing. J. Mater. Chem. B 2018, 6, 6207– 6211,  DOI: 10.1039/c8tb02167h
    Google Scholar
    46
    Three hidden talents in one framework: a terephthalic acid-coordinated cupric metal-organic framework with cascade cysteine oxidase- and peroxidase-mimicking activities and stimulus-responsive fluorescence for cysteine sensing
    Li, Xin; Zhou, Hao; Qi, Fei; Niu, Xiangheng; Xu, Xuechao; Qiu, Fengxian; He, Yanfang; Pan, Jianming; Ni, Liang
    Journal of Materials Chemistry B: Materials for Biology and Medicine (2018), 6 (39), 6207-6211CODEN: JMCBDV; ISSN:2050-7518. (Royal Society of Chemistry)
    A metal-org. framework (CuBDC) that possesses cascade cysteine oxidase- and peroxidase-mimicking activities and stimulus-responsive fluorescence was designed by coordinating cupric ions with terephthalic acid. The three-in-one CuBDC provided a new and extremely convenient turn-on fluorescence platform for selective and reliable detection of cysteine.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1cXhslCjt7fF&md5=a47fcab0445e9342006696d75c83431f
  47. 47
    Dai, R.; Zhang, X.; Liu, M.; Wu, Z.; Wang, Z. Porous metal organic framework CuBDC nanosheet incorporated thin-film nanocomposite membrane for high-performance forward osmosis. J. Membr. Sci. 2019, 573, 46– 54,  DOI: 10.1016/j.memsci.2018.11.075
    Google Scholar
    47
    Porous metal organic framework CuBDC nanosheet incorporated thin-film nanocomposite membrane for high-performance forward osmosis
    Dai, Ruobin; Zhang, Xingran; Liu, Mingxian; Wu, Zhichao; Wang, Zhiwei
    Journal of Membrane Science (2019), 573 (), 46-54CODEN: JMESDO; ISSN:0376-7388. (Elsevier B.V.)
    A thin-film nanocomposite (TFN) membrane contg. compatible 2D metal-org. framework (MOF) nanofiller in the active layer was developed to improve water permeability and antifouling capacity without compromising the selectivity for forward osmosis (FO) applications. The MOF nanosheet (copper 1,4-benzenedicarboxylate nanosheets, CuBDC-NS) was successfully incorporated into polyamide (PA) active layer during the interfacial polymn., as revealed by transmission electron microscope, X-ray diffraction and XPS. The TFN membrane exhibited higher water permeability and lower reverse solute flux (Js) compared to the pristine membrane. About 50% increase in FO water flux (Jw) and 50% decrease in specific reverse solute flux (Js/Jw) were obsd. for the TFN membrane with 0.12 wt/v % CuBDC-NS compared to the control, when 1.0 M NaCl was used as draw soln. in the active-layer facing feed-soln. (AL-FS) mode. In the continuous flow test using real wastewater as the feed-soln., the TFN membrane demonstrated a higher water flux and a slower water flux decline than the pristine one. The antifouling behavior of the CuBDC incorporated TFN membrane was assocd. with the increased hydrophilicity and biocidal ability. These results highlight the potential of CuBDC-NS incorporated TFN membranes to be used in FO processes for water desalination and wastewater treatment.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1cXisVemsLfM&md5=8f4e57be911222e3038c9bff924e1a6c
  48. 48
    Elder, A. C.; Aleksandrov, A. B.; Nair, S.; Orlando, T. M. Interactions on External MOF Surfaces: Desorption of Water and Ethanol from CuBDC Nanosheets. Langmuir 2017, 33, 10153– 10160,  DOI: 10.1021/acs.langmuir.7b01987
    Google Scholar
    48
    Interactions on External MOF Surfaces: Desorption of Water and Ethanol from CuBDC Nanosheets
    Elder, Alexander C.; Aleksandrov, Alexandr B.; Nair, Sankar; Orlando, Thomas M.
    Langmuir (2017), 33 (39), 10153-10160CODEN: LANGD5; ISSN:0743-7463. (American Chemical Society)
    The external surfaces of metal-org. framework (MOF) materials are difficult to exptl. isolate due to the high porosities of these materials. MOF surface surrogates in the form of copper benzenedicarboxylate (CuBDC) nanosheets were synthesized using a bottom-up approach, and the surface interactions of water and ethanol were investigated by temp.-programmed desorption (TPD). A method of anal. of diffusion-influenced TPD was developed to measure the desorption properties of these porous materials. This approach also allows the extn. of diffusion coeffs. from TPD data. The transmission Fourier transform IR spectra, powder X-ray diffraction patterns, and TPD data indicate that water desorbs from CuBDC nanosheets with activation energies of 44 ± 2 kJ/mol at edge sites and 58 ± 1 kJ/mol at external surface and internal and pore sites. Ethanol desorbs with activation energies of 58 ± 1 kJ/mol at internal pore sites and 66 ± 0.4 kJ/mol at external surface sites. Co-adsorption of water and ethanol was also investigated. The presence of ethanol was found to inhibit the desorption of water, resulting in a water desorption process with an activation energy of 68 ± 0.7 kJ/mol.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2sXhsVKhtLfJ&md5=58693e75b161ff0971981f4fb3c084bb
  49. 49
    Wang, B.; Jin, J.; Ding, B.; Han, X.; Han, A.; Liu, J. General Approach to Metal-Organic Framework Nanosheets With Controllable Thickness by Using Metal Hydroxides as Precursors. Front. Mater. 2020, 7, 1– 7,  DOI: 10.3389/fmats.2020.00037
    Google Scholar
    There is no corresponding record for this reference.
  50. 50
    Kassem, A. A.; Abdelhamid, H. N.; Fouad, D. M.; Ibrahim, S. A. Metal-organic frameworks (MOFs) and MOFs-derived CuO@C for hydrogen generation from sodium borohydride. Int. J. Hydrogen Energy 2019, 44, 31230– 31238,  DOI: 10.1016/j.ijhydene.2019.10.047
    Google Scholar
    50
    Metal-organic frameworks (MOFs) and MOFs-derived CuO@C for hydrogen generation from sodium borohydride
    Kassem, Ahlam Azzam; Abdelhamid, Hani Nasser; Fouad, Dina M.; Ibrahim, Said A.
    International Journal of Hydrogen Energy (2019), 44 (59), 31230-31238CODEN: IJHEDX; ISSN:0360-3199. (Elsevier Ltd.)
    Hydrogen gas has been considered as one of the promising sources of energy. Thus, several strategies including the hydrolysis of hydrides have been reported for hydrogen prodn. However, effective catalysts are highly required to improve the hydrogen generation rate. Two dimensional metal-org. frameworks (copper-benzene-1,4-dicarboxylic, CuBDC), and CuBDC-derived CuO@C were synthesized, characterized and applied as catalysts for hydrogen prodn. using the hydrolysis and methanolysis of sodium borohydride (NaBH4). CuBDC, and CuO@C display hydrogen generation rate of 7620, and 7240 mlH2·g-1cat· min-1, resp. for hydrolysis. While, CuBDC offers hydrogen generation rate of 9060 mlH2·g-1cat· min-1 for methanolysis. Both catalysts required short reaction time, and showed good recyclability. The materials may open new venues for efficient catalyst for energy-based applications.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1MXitVCksbvL&md5=0f35c6738a0cf086b4c6f3f2a0974fe4
  51. 51
    Yim, C.; Jeon, S. Direct synthesis of Cu-BDC frameworks on a quartz crystal microresonator and their application to studies of n-hexane adsorption. RSC Adv. 2015, 5, 67454– 67458,  DOI: 10.1039/c5ra11686d
    Google Scholar
    52
    Direct synthesis of Cu-BDC frameworks on a quartz crystal microresonator and their application to studies of n-hexane adsorption
    Yim, Changyong; Jeon, Sangmin
    RSC Advances (2015), 5 (83), 67454-67458CODEN: RSCACL; ISSN:2046-2069. (Royal Society of Chemistry)
    We developed a facile route for synthesizing Cu-BDC frameworks using metallic copper as a metal ion source. A thin film of copper was vacuum deposited onto a quartz crystal microresonator (QCM) and converted to Cu-BDC frameworks via a solvothermal reaction. The initially superhydrophilic Cu-BDC surface became superhydrophobic upon being treated with octadecyltrichlorosilane (ODTS). Exposure of the Cu-BDC-coated quartz crystal microresonator (CuBDC-QCM) to various concns. of n-hexane vapor induced changes in the resonance frequency and Q factor of the resonator that were related to the adsorbed mass of n-hexane and the modulus of the Cu-BDC layer, resp. The mass of n-hexane vapor adsorbed on the superhydrophobic Cu-BDC layer was found to be three times that on the superhydrophilic Cu-BDC layer. Furthermore, the adsorption of n-hexane on the superhydrophobic Cu-BDC layer induced an increase in the modulus of the framework whereas the adsorption on the superhydrophilic layer induced a decrease in the modulus of the framework. These opposite changes were attributed to differences in the binding sites of n-hexane vapor inside the framework.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2MXht1KhsLzE&md5=be6701a0dd460842fab2dea964c0e567
  52. 52
    Zhang, F. Y.; Zhang, J. L.; Zhang, B. X.; Zheng, L. R.; Cheng, X. Y.; Wan, Q.; Han, B. X.; Zhang, J. CO2 controls the oriented growth of metal-organic framework with highly accessible active sites. Nat. Commun. 2020, 11, 1– 8,  DOI: 10.1038/s41467-020-15200-4
    Google Scholar
    There is no corresponding record for this reference.

Cited By

ARTICLE SECTIONS
Jump To

This article is cited by 3 publications.

  1. B. Dulani Dhanapala, Dayton L. Maglich, Mary E. Anderson. Impact of Surface Functionalization and Deposition Method on Cu-BDC surMOF Formation, Morphology, Crystallinity, and Stability. Langmuir 2023, 39 (34) , 12196-12205. https://doi.org/10.1021/acs.langmuir.3c01505
  2. Sara E. Skrabalak, Ramanathan Vaidhyanathan. The Chemistry of Metal Organic Framework Materials. Chemistry of Materials 2023, 35 (15) , 5713-5722. https://doi.org/10.1021/acs.chemmater.3c01729
  3. Katsuhiko Ariga. Chemistry of Materials Nanoarchitectonics for Two-Dimensional Films: Langmuir–Blodgett, Layer-by-Layer Assembly, and Newcomers. Chemistry of Materials 2023, 35 (14) , 5233-5254. https://doi.org/10.1021/acs.chemmater.3c01291
Download PDF

  • Abstract

    High Resolution Image
    Download MS PowerPoint Slide

    Figure 1

    Figure 1. Scheme of the sALD setup outlining the peristaltic pump arrangement with the connections to the reaction chamber and the growth of Cu-BDC. A corresponds to the first precursor path (Cu2(OAc)4), B to the second precursor path (terephthalic acid), and S to the solvent path (ethanol). Furthermore, the size of the Cu-BDC unit cell of 14 Å is indicated.

    High Resolution Image
    Download MS PowerPoint Slide

    Figure 2

    Figure 2. (a) Linear Evolution of the film thickness as a function of the number of sALD growth cycles for the sALD pulse/exposure/purge sequence of 30 s/30 s/90 s. (b) Saturation curve of the sALD growth rate as a function of the pulse and purge durations (green and blue, respectively). For the saturation study, the pulse duration of both precursors was varied simultaneously. The error bars show the uncertainty on the measurements. They correspond to the standard deviation averaged over at least 5 points measured by spectroscopic ellipsometry on a Si substrate with native oxide. The growth rate is 4.5 Å/ALD cycle.

    High Resolution Image
    Download MS PowerPoint Slide

    Figure 3

    Figure 3. (a) PM-IRRAS and Raman spectra of Cu-BDC grown by sALD with 50 ALD cycles and (b) XRD diffractogram of Cu-BDC grown by sALD with 50, 100, 200, 300, and 400 ALD cycles.

    High Resolution Image
    Download MS PowerPoint Slide

    Figure 4

    Figure 4. Microscopic characterization of Cu-BDC films grown with 10 sALD cycles. (a) SEM micrograph of surface morphology and (b) AFM micrograph of Cu-BDC film grown with 10 deposition cycles by sALD. (c) Phase contrast data of the AFM micrograph (scale −75 to 75°). (d) Low-magnification AFM micrograph of the same film. Micrographs (b) and (c) display the same area of the film, which differs from those shown in (a) and (d). The rms roughness obtained from image (d) is 5.1 nm.

    High Resolution Image
    Download MS PowerPoint Slide

    Figure 5

    Figure 5. (a,d) AFM micrographs of Cu-BDC deposited by sALD with 10 deposition cycles, (b,e) dip-coating, and (c,f) spray-coating (a. k. a. “liquid-phase epitaxy” and “layer-by-layer” deposition). The micrographs (a–c) represent the phase contrast (the value varies between 0 and 70°) and (d–f) are the respective topographic data with a threshold mask, the height scale varying from 0 to 50 nm for (d,e) and from 0 to 25 nm for (f). The corresponding mask appears in red, and the unmasked region appears in black and white. The details of masking are described in the Experimental Methods section. The lateral scale bar represents 250 nm.

    High Resolution Image
    Download MS PowerPoint Slide

  • References

    ARTICLE SECTIONS
    Jump To

    This article references 52 other publications.

    1. 1
      James, S. L. Metal-organic frameworks. Chem. Soc. Rev. 2003, 32, 276– 288,  DOI: 10.1039/b200393g
      Google Scholar
      1
      Metal-organic frameworks
      James, Stuart L.
      Chemical Society Reviews (2003), 32 (5), 276-288CODEN: CSRVBR; ISSN:0306-0012. (Royal Society of Chemistry)
      A review. Metal-org. frameworks are a recently-identified class of porous polymeric material, consisting of metal ions linked together by org. bridging ligands, and are a new development on the interface between mol. coordination chem. and materials science. A range of novel structures was prepd. which feature amongst the largest pores known for cryst. compds., very high sorption capacities and complex sorption behavior not seen in aluminosilicate zeolites. The development of synthetic approaches to these materials and studies of their properties are reviewed.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD3sXmtFOltLY%253D&md5=e9e83de0580c0b7dc9929ea3594efe12
    2. 2
      Li, H.; Eddaoudi, M.; O’Keeffe, M.; Yaghi, O. M. Design and synthesis of an exceptionally stable and highly porous metal-organic framework. Nature 1999, 402, 276– 279,  DOI: 10.1038/46248
      Google Scholar
      2
      Design and synthesis of an exceptionally stable and highly porous metal-organic framework
      Li, Hailian; Eddaoudi, Mohamed; O'Keeffe, M.; Yaghi, M.
      Nature (London) (1999), 402 (6759), 276-279CODEN: NATUAS; ISSN:0028-0836. (Macmillan Magazines)
      Open metal-org. frameworks are widely regarded as promising materials for applications in catalysis, sepn., gas storage and mol. recognition. Compared to conventionally used microporous inorg. materials such as zeolites, these org. structures have the potential for more flexible rational design, through control of the architecture and functionalization of the pores. So far, the inability of these open frameworks to support permanent porosity and to avoid collapsing in the absence of guest mols., such as solvents, has hindered further progress in the field. The authors report the synthesis of a metal-org. framework, Zn4O(BDC)3.(DMF)8.(PhCl) (named MOF-5, where BDC = 1,4-benzenedicarboxylate), which remains cryst., as evidenced by x-ray single-crystal analyses, and stable when fully desolvated and when heated up to 300°. This synthesis is achieved by borrowing ideas from metal carboxylate cluster chem., where an org. dicarboxylate linker was used in a reaction that gives supertetrahedron clusters when capped with monocarboxylates. The rigid and divergent character of the added linker allows the articulation of the clusters into a three-dimensional framework resulting in a structure with higher apparent surface area and pore vol. than most porous cryst. zeolites. This simple and potentially universal design strategy is currently being pursued in the synthesis of new phases and composites, and for gas-storage applications.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADyaK1MXnvFSiuro%253D&md5=68f27e20a7e4e15ea2c2f49a2a61e98a
    3. 3
      Rowsell, J. L. C.; Yaghi, O. M. Metal-organic frameworks: a new class of porous materials. Microporous Mesoporous Mater. 2004, 73, 3– 14,  DOI: 10.1016/j.micromeso.2004.03.034
      Google Scholar
      3
      Metal-organic frameworks: a new class of porous materials
      Rowsell, Jesse L. C.; Yaghi, Omar M.
      Microporous and Mesoporous Materials (2004), 73 (1-2), 3-14CODEN: MIMMFJ; ISSN:1387-1811. (Elsevier Science B.V.)
      A review of the synthesis, structure, and properties of metal-org. frameworks (MOFs) is presented, highlighting the important advances in their research over the past decade. This new class of porous materials is attracting attention due to demonstrations of their large pore sizes, high apparent surface areas, selective uptake of small mols., and optical or magnetic responses to the inclusion of guests. More importantly, their synthesis from mol. building blocks holds the potential for directed tailoring of these properties.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD2cXlvVWrur4%253D&md5=63063a3480702ad0f211a6d5f0fd0491
    4. 4
      Lee, J.; Farha, O. K.; Roberts, J.; Scheidt, K. A.; Nguyen, S. T.; Hupp, J. T. Metal-organic framework materials as catalysts. Chem. Soc. Rev. 2009, 38, 1450– 1459,  DOI: 10.1039/b807080f
      Google Scholar
      4
      Metal-organic framework materials as catalysts
      Lee, Jeong Yong; Farha, Omar K.; Roberts, John; Scheidt, Karl A.; Nguyen, Son Binh T.; Hupp, Joseph T.
      Chemical Society Reviews (2009), 38 (5), 1450-1459CODEN: CSRVBR; ISSN:0306-0012. (Royal Society of Chemistry)
      A review; a crit. review of the emerging field of MOF-based catalysis is presented. Discussed are examples of: (a) opportunistic catalysis with metal nodes, (b) designed catalysis with framework nodes, (c) catalysis by homogeneous catalysts incorporated as framework struts, (d) catalysis by MOF-encapsulated mol. species, (e) catalysis by metal-free org. struts or cavity modifiers, and (f) catalysis by MOF-encapsulated clusters.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD1MXkvVamu7k%253D&md5=d9cef4eb52ffb1c73fe1195e11bace26
    5. 5
      Babaei, H., DeCoster, M. E., Jeong, M., Hassan, Z. M., Islamoglu, T., Baumgart, H., McGaughey, A. J. H., Redel, E., Farha, O. K., Hopkins, P. E., Malen, J. A., Wilmer, C. E. Observation of reduced thermal conductivity in a metal-organic framework due to the presence of adsorbates. Nat. Commun. 2020, 11(). DOI: 10.1038/s41467-020-17822-0
      Google Scholar
      There is no corresponding record for this reference.
    6. 6
      Murray, L. J.; Dincă, M.; Long, J. R. Hydrogen storage in metal-organic frameworks. Chem. Soc. Rev. 2009, 38, 1294– 1314,  DOI: 10.1039/b802256a
      Google Scholar
      6
      Hydrogen storage in metal-organic frameworks
      Murray, Leslie J.; Dinca, Mircea; Long, Jeffrey R.
      Chemical Society Reviews (2009), 38 (5), 1294-1314CODEN: CSRVBR; ISSN:0306-0012. (Royal Society of Chemistry)
      A review of current status of hydrogen storage within metal-org. frameworks. Microporous metal-org. frameworks, having exceptionally high surface areas and chem.-tunable structures, have recently emerged as some of the most promising candidate materials. Particular emphasis is given to the relationships between structural features and the enthalpy of hydrogen adsorption, spectroscopic methods for probing framework-H2 interactions, and strategies for improving storage capacity.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD1MXkvVamuro%253D&md5=f652ac03772753d7f80244564a80e6f0
    7. 7
      Li, J. R.; Sculley, J.; Zhou, H. C. Metal-Organic Frameworks for Separations. Chem. Rev. 2012, 112, 869– 932,  DOI: 10.1021/cr200190s
      Google Scholar
      7
      Metal-Organic Frameworks for Separations
      Li, Jian-Rong; Sculley, Julian; Zhou, Hong-Cai
      Chemical Reviews (Washington, DC, United States) (2012), 112 (2), 869-932CODEN: CHREAY; ISSN:0009-2665. (American Chemical Society)
      A review. This article reviews the metal-org. frameworks (MOFs), a new class of porous solid materials. Their performances for applications in sepns. and purifications is attracting intense interest of researchers working in the fields of chem., chem. engineering, materials science, and others. Despite being in its infancy, the research progress in this subject has already shown that MOFs are promising for sepn. applications.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3MXht1OnsbbL&md5=635f36e2682f7fbc651f5021d591a1cf
    8. 8
      Chen, X.; Wang, Z.; Lin, P.; Zhang, K.; Baumgart, H.; Redel, E.; Wöll, C. Thermoelectric Properties of Highly Ordered Metal-Organic Framework Films. ECS Trans. 2016, 75, 119– 126,  DOI: 10.1149/07513.0119ecst
      Google Scholar
      8
      Thermoelectric properties of highly ordered metal-organic framework films
      Chen, Xin; Wang, Zhengbang; Lin, Pengtao; Zhang, Kai; Baumgart, Helmut; Redel, Engelbert; Woll, Christof
      ECS Transactions (2016), 75 (13, Emerging Nanomaterials and Devices), 119-126CODEN: ECSTF8; ISSN:1938-5862. (Electrochemical Society)
      In this work, quasi-liq. epitaxially highly oriented Surface Anchored Metal-Org. Framework (SURMOF) films and for comparison random polycryst. MOF films loaded with tetracyano-quinodimethane (TCNQ) infiltration were fabricated and characterized. The horizontal Seebeck coeff. of the oriented SURMOF films and the random polycryst. MOF films parallel to the sample surface was measured and has been discussed. The polycryst. MOF films exhibit a high Seebeck coeff. of 949.9 μV/K at 290 K, while the horizontal Seebeck coeff. of oriented SURMOF films is practically around 0 μV/K. Because the quasi-epitaxial oriented SURMOF films are highly anisotropic, there is no measurable horizontal carrier transport parallel to the SURMOF surface. However in contrast to oriented SURMOF films, the elec. properties of random polycryst. MOF films with sputtered Au contact pads could be measured. The high Seebeck coeff. of these random polycryst. MOF films demonstrate a promising application potential of MOF films in future thermoelec. and electronic devices.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1cXovVentrw%253D&md5=1cda3bed0a6b737b4c04f4cb06c97c58
    9. 9
      Chen, X.; Wang, Z. B.; Hassan, Z. M.; Lin, P. T.; Zhang, K.; Baumgart, H.; Redel, E. Seebeck Coefficient Measurements of Polycrystalline and Highly Ordered Metal-Organic Framework Thin Films. ECS J. Solid State Sci. Technol. 2017, 6, P150– P153,  DOI: 10.1149/2.0161704jss
      Google Scholar
      9
      Seebeck Coefficient Measurements of Polycrystalline and Highly Ordered Metal-Organic Framework Thin Films
      Chen, Xin; Wang, Zhengbang; Hassan, Zeinab Mohamed; Lin, Pengtao; Zhang, Kai; Baumgart, Helmut; Redel, Engelbert
      ECS Journal of Solid State Science and Technology (2017), 6 (4), P150-P153CODEN: EJSSBG; ISSN:2162-8769. (Electrochemical Society)
      In this work highly oriented Surface Anchored Metal-Org. Framework (SURMOF) films were fabricated quasi-epitaxial and were elec. characterized by Seebeck anal. and benchmarked against random polycryst. MOF films loaded with tetracyano-quinodimethane (TCNQ) infiltration. The horizontal Seebeck coeff. of the oriented SURMOF films and the random polycryst. MOF films parallel to the sample surface was measured and has been discussed. The isotropic random polycryst. MOF films exhibit a high pos. Seebeck coeff. of 422.32 μV/K at 350 K. However, the horizontal Seebeck coeff. of highly oriented SURMOF films fluctuates around 0 μV/K instead. Because the quasi-epitaxial oriented SURMOF films are highly anisotropic, there is no measurable horizontal carrier transport parallel to the SURMOF surface. However, in contrast to highly oriented (002) SURMOF films, the in-plane thermoelec. properties of random polycryst. MOF films with sputtered Au contact pads could be measured due to the isotropic nature of these films. The high Seebeck coeff. of these random polycryst. MOF films demonstrates promising application potential of MOF films in future thermoelec. and electronic devices.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2sXktlKisLs%253D&md5=3115ad94f6d16cfdd737079b24360e53
    10. 10
      Redel, E.; Baumgart, H. Thermoelectric porous MOF based hybrid materials. APL Mater. 2020, 8, 060902,  DOI: 10.1063/5.0004699
      Google Scholar
      10
      Thermoelectric porous MOF based hybrid materials
      Redel, Engelbert; Baumgart, Helmut
      APL Materials (2020), 8 (6), 060902CODEN: AMPADS; ISSN:2166-532X. (American Institute of Physics)
      Porous hybrid materials and MOF (Metal-Org.-Framework) films represent modern designer materials that exhibit many requirements of a near ideal and tunable future thermoelec. (TE) material. In contrast to traditional semiconducting bulk TE materials, porous hybrid MOF templates can be used to overcome some of the constraints of physics in bulk TE materials. These porous hybrid systems are amenable for simulation and modeling to design novel optimized electron-crystal phonon-glass materials with potentially very high ZT (figure of merit) nos. Porous MOF and hybrid materials possess an ultra-low thermal cond., which can be further modulated by phonon engineering within their complex porous and hierarchical architecture to advance the TE figure of merit (ZT). This Perspective review discusses recent results of MOF TE materials and provides a future outlook and the vision to the search for the next generation TE porous hybrid and MOF materials, which could be part of the green renewable energy revolution with novel materials of sustainably high ZT values. (c) 2020 American Institute of Physics.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BB3cXhtFGhtbrK&md5=59f2d78fc71aabbf6ad2b164c15adc2b
    11. 11
      Kreno, L. E.; Leong, K.; Farha, O. K.; Allendorf, M.; Van Duyne, R. P.; Hupp, J. T. Metal-Organic Framework Materials as Chemical Sensors. Chem. Rev. 2012, 112, 1105– 1125,  DOI: 10.1021/cr200324t
      Google Scholar
      11
      Metal-Organic Framework Materials as Chemical Sensors
      Kreno, Lauren E.; Leong, Kirsty; Farha, Omar K.; Allendorf, Mark; Van Duyne, Richard P.; Hupp, Joseph T.
      Chemical Reviews (Washington, DC, United States) (2012), 112 (2), 1105-1125CODEN: CHREAY; ISSN:0009-2665. (American Chemical Society)
      A review. The authors present a crit. review of the literature on metal-org. frameworks (MOFs) as chem. sensors. The authors begin by briefly examg. challenges relating to MOF sensor development including the design of MOFs with desirable properties, incorporation of appropriate signal transduction capabilities, and integration of MOFs into devices by employing thin-film growth techniques. Subsequent sections discuss specific examples of MOF sensors, categorized by method of signal transduction. Sensors based on MOF photoluminescence are discussed briefly. The authors have limited the review of luminescence-based sensors to a small no. of recent reports where the porous MOF architecture, or its chem. compn., imparts selective sensing capabilities. Scintillating MOFs that luminesce in the presence of radioactive analytes are also discussed. Other signal transduction schemes that use photons include various kinds of optical interferometry, analyte modulation of localized surface plasmon resonance energies, and solvatochromism. Mech. signal-transduction schemes employed with MOFs include ones based on surface acoustic wave, quartz crystal microbalance, and microcantilever devices. Elec. schemes thus far were limited to ones based on impedance spectroscopy.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3MXhsVCgtL%252FI&md5=f6ed572725bc067ee8da81880bf1ec90
    12. 12
      Bloch, E. D.; Murray, L. J.; Queen, W. L.; Chavan, S.; Maximoff, S. N.; Bigi, J. P.; Krishna, R.; Peterson, V. K.; Grandjean, F.; Long, G. J.; Smit, B.; Bordiga, S.; Brown, C. M.; Long, J. R. Selective Binding of O-2 over N-2 in a Redox-Active Metal-Organic Framework with Open Iron(II) Coordination Sites. J. Am. Chem. Soc. 2011, 133, 14814– 14822,  DOI: 10.1021/ja205976v
      Google Scholar
      12
      Selective Binding of O2 over N2 in a Redox-Active Metal-Organic Framework with Open Iron(II) Coordination Sites
      Bloch, Eric D.; Murray, Leslie J.; Queen, Wendy L.; Chavan, Sachin; Maximoff, Sergey N.; Bigi, Julian P.; Krishna, Rajamani; Peterson, Vanessa K.; Grandjean, Fernande; Long, Gary J.; Smit, Berend; Bordiga, Silvia; Brown, Craig M.; Long, Jeffrey R.
      Journal of the American Chemical Society (2011), 133 (37), 14814-14822CODEN: JACSAT; ISSN:0002-7863. (American Chemical Society)
      The air-free reaction between FeCl2 and H4dobdc (dobdc4- = 2,5-dioxido-1,4-benzenedicarboxylate) in a mixt. of N,N-dimethylformamide (DMF) and methanol affords Fe2(dobdc)·4DMF, a metal-org. framework adopting the MOF-74 (or CPO-27) structure type. The desolvated form of this material displays a Brunauer-Emmett-Teller (BET) surface area of 1360 m2/g and features a hexagonal array of one-dimensional channels lined with coordinatively unsatd. FeII centers. Gas adsorption isotherms at 298 K indicate that Fe2(dobdc) binds O2 preferentially over N2, with an irreversible capacity of 9.3%, corresponding to the adsorption of one O2 mol. per two iron centers. Remarkably, at 211 K, O2 uptake is fully reversible and the capacity increases to 18.2%, corresponding to the adsorption of one O2 mol. per iron center. Mossbauer and IR spectra are consistent with partial charge transfer from iron(II) to O2 at low temp. and complete charge transfer to form iron(III) and O22- at room temp. The results of Rietveld analyses of powder neutron diffraction data (4 K) confirm this interpretation, revealing O2 bound to iron in a sym. side-on mode with dO-O = 1.25(1) Å at low temp. and in a slipped side-on mode with dO-O = 1.6(1) Å when oxidized at room temp. Application of ideal adsorbed soln. theory in simulating breakthrough curves shows Fe2(dobdc) to be a promising material for the sepn. of O2 from air at temps. well above those currently employed in industrial settings.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3MXhtV2isbnM&md5=bb45728676bb33f13be541d2cc6d0279
    13. 13
      Bloch, E. D.; Queen, W. L.; Krishna, R.; Zadrozny, J. M.; Brown, C. M.; Long, J. R. Hydrocarbon Separations in a Metal-Organic Framework with Open Iron(II) Coordination Sites. Science 2012, 335, 1606– 1610,  DOI: 10.1126/science.1217544
      Google Scholar
      13
      Hydrocarbon Separations in a Metal-Organic Framework with Open Iron(II) Coordination Sites
      Bloch, Eric D.; Queen, Wendy L.; Krishna, Rajamani; Zadrozny, Joseph M.; Brown, Craig M.; Long, Jeffrey R.
      Science (Washington, DC, United States) (2012), 335 (6076), 1606-1610CODEN: SCIEAS; ISSN:0036-8075. (American Association for the Advancement of Science)
      The energy costs assocd. with large-scale industrial sepn. of light hydrocarbons by cryogenic distn. could potentially be lowered through development of selective solid adsorbents that operate at higher temps. Here, the metal-org. framework Fe2(dobdc) (dobdc4- : 2,5-dioxido-1,4-benzenedicarboxylate) is demonstrated to exhibit excellent performance characteristics for sepn. of ethylene/ethane and propylene/propane mixts. at 318 K. Breakthrough data obtained for these mixts. provide exptl. validation of simulations, which in turn predict high selectivities and capacities of this material for the fractionation of methane/ethane/ethylene/acetylene mixts., removal of acetylene impurities from ethylene, and membrane-based olefin/paraffin sepns. Neutron powder diffraction data confirm a side-on coordination of acetylene, ethylene, and propylene at the iron(II) centers, while also providing solid-state structural characterization of the much weaker interactions of ethane and propane with the metal.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC38XksVyqsLc%253D&md5=d149ed45c3e688d5e4ee63d75629bd4f
    14. 14
      Borfecchia, E.; Maurelli, S.; Gianolio, D.; Groppo, E.; Chiesa, M.; Bonino, F.; Lamberti, C. Insights into Adsorption of NH3 on HKUST-1 Metal–Organic Framework: A Multitechnique Approach. J. Phys. Chem. C 2012, 116, 19839– 19850,  DOI: 10.1021/jp305756k
      Google Scholar
      14
      Insights into Adsorption of NH3 on HKUST-1 Metal-Organic Framework: A Multitechnique Approach
      Borfecchia, Elisa; Maurelli, Sara; Gianolio, Diego; Groppo, Elena; Chiesa, Mario; Bonino, Francesca; Lamberti, Carlo
      Journal of Physical Chemistry C (2012), 116 (37), 19839-19850CODEN: JPCCCK; ISSN:1932-7447. (American Chemical Society)
      We report a careful characterization of the interaction of NH3 with the Cu(II) sites of the [Cu2C4O8] paddle-wheel cornerstone of the HKUST-1 metallorg. framework, also known as Cu3(BTC)2. The general picture emerging from combining XRPD, EXAFS, XANES, mid- and far-IR, DRUV-vis, and EPR techniques is that the presence of traces of water has relevant consequences on the effect of ammonia on the MOF framework. NH3 adsorption on the dry system results in a strong chemisorption on Cu(II) sites that distorts the framework, keeping the crystallinity of the material. Perturbation obsd. upon NH3 adsorption is analogous to that obsd. for H2O, but noticeably enhanced. When the adsorption of ammonia occurs in humid conditions, a time-dependent, much deeper modification of the system is obsd. by all of the considered techniques. On a methodol. ground, it is worth noticing that we used the optimization of XANES spectra to validate the bond distance obtained by EXAFS.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC38XhtFChtbvO&md5=9ac9922154e664d3bfa180e2caf761a9
    15. 15
      Kim, H. K.; Yun, W. S.; Kim, M.-B.; Kim, J. Y.; Bae, Y.-S.; Lee, J.; Jeong, N. C. A Chemical Route to Activation of Open Metal Sites in the Copper-Based Metal–Organic Framework Materials HKUST-1 and Cu-MOF-2. J. Am. Chem. Soc. 2015, 137, 10009– 10015,  DOI: 10.1021/jacs.5b06637
      Google Scholar
      15
      A Chemical Route to Activation of Open Metal Sites in the Copper-Based Metal-Organic Framework Materials HKUST-1 and Cu-MOF-2
      Kim, Hong Ki; Yun, Won Seok; Kim, Min-Bum; Kim, Jeung Yoon; Bae, Youn-Sang; Lee, JaeDong; Jeong, Nak Cheon
      Journal of the American Chemical Society (2015), 137 (31), 10009-10015CODEN: JACSAT; ISSN:0002-7863. (American Chemical Society)
      Methylene chloride (MC) has been shown to perform the activation of metal-org. frameworks: this process can serve as an alternative "chem. route" for the activation that does not require applying heat. On the basis of Raman spectra, the authors propose a plausible mechanism for the chem. activation, in which the function of MC is possibly due to its coordination with the Cu2+ center and subsequent spontaneous decoordination. Using HKUST-1 film, it was further demonstrated that this chem. activation route is highly suitable for activating large-area MOF films.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2MXhtF2lt7%252FN&md5=3abbd20f8b083fc1bd8a155e2963959a
    16. 16
      Clark, R.; Tapily, K.; Yu, K. H.; Hakamata, T.; Consiglio, S.; O’Meara, D.; Wajda, C.; Smith, J.; Leusink, G. Perspective: New process technologies required for future devices and scaling. APL Mater. 2018, 6, 058203,  DOI: 10.1063/1.5026805
      Google Scholar
      16
      Perspective: New process technologies required for future devices and scaling
      Clark, R.; Tapily, K.; Yu, K.-H.; Hakamata, T.; Consiglio, S.; O'Meara, D.; Wajda, C.; Smith, J.; Leusink, G.
      APL Materials (2018), 6 (5), 058203/1-058203/12CODEN: AMPADS; ISSN:2166-532X. (American Institute of Physics)
      This paper presents an overview and perspective on processing technologies required for continued scaling of leading edge and emerging semiconductor devices. We introduce the main drivers and trends affecting future semiconductor device scaling and provide examples of emerging devices and architectures that may be implemented within the next 10-20 yr. We summarize multiple active areas of research to explain how future thin film deposition, etch, and patterning technologies can enable 3D (vertical) power, performance, area, and cost scaling. Emerging and new process technologies will be required to enable improved contacts, scaled and future devices and interconnects, monolithic 3D integration, and new computing architectures. These process technologies are explained and discussed with a focus on opportunities for continued improvement and innovation. (c) 2018 American Institute of Physics.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1cXhtVGisr7L&md5=23afc1e8855db73cb2a0d6e2f2017d77
    17. 17
      Tapily, K.; Jakes, J.; Stone, D.; Shrestha, P.; Gu, D.; Baumgart, H.; Elmustafa, A. Nanomechanical Properties of High-K Dielectrics Grown by Atomic Layer Deposition. ECS Trans. 2019, 11, 123– 130
      Google Scholar
      There is no corresponding record for this reference.
    18. 18
      Zhu, X.; Gu, D.; Li, Q.; Ioannou, D. E.; Baumgart, H.; Suehle, J. S.; Richter, C. A. Silicon nanowire NVM with high-k gate dielectric stack. Microelectron. Eng. 2009, 86, 1957– 1960,  DOI: 10.1016/j.mee.2009.03.095
      Google Scholar
      18
      Silicon nanowire NVM with high-k gate dielectric stack
      Zhu, Xiaoxiao; Gu, D.; Li, Qiliang; Ioannou, D. E.; Baumgart, H.; Suehle, J. S.; Richter, C. A.
      Microelectronic Engineering (2009), 86 (7-9), 1957-1960CODEN: MIENEF; ISSN:0167-9317. (Elsevier B.V.)
      Three flash memory cell structures with silicon nanowire channels and high-k dielec. stacks were fabricated with a "self-aligning" process and their characteristics are reported and compared in this paper: a Metal/SiO2/HfO2/SiO2/Si (MOHOS) cell with a SiO2 blocking layer and two Metal/Al2O3/HfO2/SiO2/Si (MAHOS) cells with Al2O3, all with HfO2 as the charge trapping layer. Compared to (control) planar cells, all three operate at higher speeds, attributed to the enhanced elec. field across the tunneling oxide surrounding the channel. The MAHOS cells (Al2O3 blocking layer) outperform the MOHOS cells (SiO2 blocking layer) and both have large memory window, fast operation speed, good endurance and retention.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD1MXmsFGrsLk%253D&md5=f445a4f5814fb35d1fb2dcc8063f30db
    19. 19
      Puurunen, R. L. Surface chemistry of atomic layer deposition: A case study for the trimethylaluminum/water process. J. Appl. Phys. 2005, 97, 1– 52,  DOI: 10.1063/1.1940727
      Google Scholar
      There is no corresponding record for this reference.
    20. 20
      Sundberg, P.; Karppinen, M. Organic and inorganic–organic thin film structures by molecular layer deposition: A review. Beilstein J. Nanotechnol. 2014, 5, 1104– 1136,  DOI: 10.3762/bjnano.5.123
      Google Scholar
      20
      Organic and inorganic-organic thin film structures by molecular layer deposition: a review
      Sundberg, Pia; Karppinen, Maarit
      Beilstein Journal of Nanotechnology (2014), 5 (), 1104-1136, 33 pp.CODEN: BJNEAH; ISSN:2190-4286. (Beilstein-Institut zur Foerderung der Chemischen Wissenschaften)
      The possibility to deposit purely org. and hybrid inorg.-org. materials in a way parallel to the state-of-the-art gas-phase deposition method of inorg. thin films, i.e., at. layer deposition (ALD), is currently experiencing a strongly growing interest. Like ALD in case of the inorgs., the emerging mol. layer deposition (MLD) technique for org. constituents can be employed to fabricate high-quality thin films and coatings with thickness and compn. control on the mol. scale, even on complex three-dimensional structures. Moreover, by combining the two techniques, ALD and MLD, fundamentally new types of inorg.-org. hybrid materials can be produced. In this review article, we first describe the basic concepts regarding the MLD and ALD/MLD processes, followed by a comprehensive review of the various precursors and precursor pairs so far employed in these processes. Finally, we discuss the first proof-of-concept expts. in which the newly developed MLD and ALD/MLD processes are exploited to fabricate novel multilayer and nanostructure architectures by combining different inorg., org. and hybrid material layers into on-demand designed mixts., superlattices and nanolaminates, and employing new innovative nanotemplates or post-deposition treatments to, e.g., selectively decomp. parts of the structure. Such layer-engineered and/or nanostructured hybrid materials with exciting combinations of functional properties hold great promise for high-end technol. applications.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2cXhs1ehtb7O&md5=11468e5290fe4593b537db5bc9d9f37a
    21. 21
      Han, S.; Mullins, C. B. Current Progress and Future Directions in Gas-Phase Metal-Organic Framework Thin-Film Growth. ChemSusChem 2020, 13, 5433– 5442,  DOI: 10.1002/cssc.202001504
      Google Scholar
      21
      Current Progress and Future Directions in Gas-Phase Metal-Organic Framework Thin-Film Growth
      Han, Sungmin; Mullins, C. Buddie
      ChemSusChem (2020), 13 (20), 5433-5442CODEN: CHEMIZ; ISSN:1864-5631. (Wiley-VCH Verlag GmbH & Co. KGaA)
      A review. Deposition of materials as a thin film is important for various applications, such as sensors, microelectronic devices, and membranes. There have been breakthroughs in gas-phase metal-org. framework (MOF) thin-film growth, which is more applicable to micro- and nanofabrication processes and also less harmful to the environment than solvent-based methods. Three different types of gas-phase MOF thin film deposition methods have been developed using chem. vapor deposition (CVD), at. layer deposition (ALD), and phys. vapor deposition (PVD)-CVD combined techniques. The CVD-based method basically converts metal oxide layers into MOF thin films by exposing the surface to ligand vapor. The ALD-based method allows growing MOF thin films following layer-by-layer (LBL) growth by sequentially exposing gas-phase metal and ligand precursors. The PVD-CVD method uses PVD for metal deposition and CVD for ligand deposition, which is similar to LBL growth. These gas-phase growth methods can broaden the use of MOFs in diverse areas. Herein, the current progress of gas-phase MOF thin film growth is discussed and future directions suggested.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BB3cXhslOqtrrE&md5=76236ae855b968a78b432d58da3974ae
    22. 22
      Meng, X. An overview of molecular layer deposition for organic and organic–inorganic hybrid materials: mechanisms, growth characteristics, and promising applications. J. Mater. Chem. A 2017, 5, 18326– 18378,  DOI: 10.1039/c7ta04449f
      Google Scholar
      22
      An overview of molecular layer deposition for organic and organic-inorganic hybrid materials: mechanisms, growth characteristics, and promising applications
      Meng, Xiangbo
      Journal of Materials Chemistry A: Materials for Energy and Sustainability (2017), 5 (35), 18326-18378CODEN: JMCAET; ISSN:2050-7496. (Royal Society of Chemistry)
      It was a strong desire for researchers to control material growth at the mol. and at. levels. Mol. and at. layer deposition (MLD and ALD) are two such techniques. In comparison to a huge amt. of studies invested on ALD, the research on MLD is still relatively limited due to the difficulty in finding suitable coupling precursors, but the recently successful applications of MLD are encouraging in many areas such as surface engineering, new energies, and catalysis. In order to further stimulate more research enthusiasm and educate beginners, we contribute this thorough survey on the progress of MLD. This review is a comprehensive account of MLD processes for org. and org.-inorg. materials, covering precursors, surface chem., growth characteristics, film properties, and promising applications. The work provides a complete summary of over 80 MLD processes for growing over 20 types of pure polymeric and metal-based hybrid polymeric materials. Given their similarities in mechanisms, we made a comparative description between ALD and MLD, and discussed the uncountable possibilities to combine both ALD and MLD for advanced materials with desirable properties. To feature and highlight the significance of MLD, this review specially gives some detailed discussions on MLD's applications in several important areas, including novel nanostructured materials, surface engineering, new energies (i.e., batteries, supercapacitors, solar cells, and water splitting), catalysis, and rewritable data storage. With this work, we expect to boost research interest and attempts at advanced materials using MLD as well as ALD.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2sXht1ektbzM&md5=8d28ef8126a56c93ee8835a80a143899
    23. 23
      Svärd, L.; Putkonen, M.; Kenttä, E.; Sajavaara, T.; Krahl, F.; Karppinen, M.; Van de Kerckhove, K.; Detavernier, C.; Simell, P. Low-Temperature Molecular Layer Deposition Using Monofunctional Aromatic Precursors and Ozone-Based Ring-Opening Reactions. Langmuir 2017, 33, 9657– 9665
      Google Scholar
      23
      Low-Temperature Molecular Layer Deposition Using Monofunctional Aromatic Precursors and Ozone-Based Ring-Opening Reactions
      Svard, Laura; Putkonen, Matti; Kentta, Eija; Sajavaara, Timo; Krahl, Fabian; Karppinen, Maarit; Van de Kerckhove, Kevin; Detavernier, Christophe; Simell, Pekka
      Langmuir (2017), 33 (38), 9657-9665CODEN: LANGD5; ISSN:0743-7463. (American Chemical Society)
      Mol. layer deposition (MLD) is an increasingly used deposition technique for producing thin coatings consisting of purely org. or hybrid inorg.-org. materials. When org. materials are prepd., low deposition temps. are often required to avoid decompn., thus causing problems with low vapor pressure precursors. Monofunctional compds. have higher vapor pressures than traditional bi- or trifunctional MLD precursors, but do not offer the required functional groups for continuing the MLD growth in subsequent deposition cycles. The authors used high vapor pressure monofunctional arom. precursors in combination with ozone-triggered ring-opening reactions to achieve sustained sequential growth. MLD depositions were carried out by using three different arom. precursors in an ABC sequence, namely with TMA + phenol + O3, TMA + 3-(trifluoromethyl)phenol + O3, and TMA + 2-fluoro-4-(trifluoromethyl)benzaldehyde + O3. The effect of hydrogen peroxide as a fourth step was evaluated for all studied processes resulting in a four-precursor ABCD sequence. According to the characterization results by ellipsometry, IR spectroscopy, and X-ray reflectivity, self-limiting MLD processes could be obtained between 75 and 150 °C with each of the three arom. precursors. In all cases, the GPC (growth per cycle) decreased with increasing temp. In situ IR spectroscopy indicated that ring-opening reactions occurred in each ABC sequence. Compositional anal. using time-of-flight elastic recoil detection indicated that fluorine could be incorporated into the film when 3-(trifluoromethyl)phenol and 2-fluoro-4-(trifluoromethyl)benzaldehyde were used as precursors.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2sXhtlyhsLrK&md5=253484c3d41a5d2eb83cec26eaf64a82
    24. 24
      George, S. M.; Yoon, B.; Dameron, A. A. Surface Chemistry for Molecular Layer Deposition of Organic and Hybrid Organic–Inorganic Polymers. Acc. Chem. Res. 2009, 42, 498– 508,  DOI: 10.1021/ar800105q
      Google Scholar
      24
      Surface Chemistry for Molecular Layer Deposition of Organic and Hybrid Organic-Inorganic Polymers
      George, Steven M.; Yoon, Byunghoon; Dameron, Arrelaine A.
      Accounts of Chemical Research (2009), 42 (4), 498-508CODEN: ACHRE4; ISSN:0001-4842. (American Chemical Society)
      A review. The fabrication of many devices in modern technol. requires techniques for growing thin films. As devices miniaturize, manufacturers will need to control thin film growth at the at. level. Because many devices have challenging morphologies, thin films must be able to coat conformally on structures with high aspect ratios. Techniques based on at. layer deposition (ALD), a special type of chem. vapor deposition, allow for the growth of ultra-thin and conformal films of inorg. materials using sequential, self-limiting reactions. Mol. layer deposition (MLD) methods extend this strategy to include org. and hybrid org.-inorg. polymeric materials. An overview of the surface chem. for MLD of org. and hybrid org.-inorg. polymers and a variety of surface chem. strategies for growing polymer thin films are outlined. Previously, surface chem. for MLD of polyamides and polyimides has used two-step AB reaction cycles using homo-bifunctional monomers. However, these monomers can react twice and eliminate active sites on the growing polymer surface. To avoid this problem, alternative precursors are used for MLD based on hetero-bifunctional monomers and ring-opening reactions. Surface activation or protected chem. functional groups can also be used. Combinations of monomers for ALD and MLD allow prepn. of hybrid org.-inorg. polymers that should display interesting properties. For example, using trimethylaluminum (TMA) and various diols, MLD of alucone org.-inorg. polymers was achieved. The chem. and phys. properties of these org.-inorg. polymers can be changed by varying the org. constituent in the diol or blending the alucone MLD films with purely inorg. ALD films to build a nanocomposite or nanolaminate. The combination of ALD and MLD reactants enlarges the no. of possible sequential self-limiting surface reactions for film growth. Extensions to three-step ABC reaction cycles also offer many advantages to avoid the use of homo-bifunctional reactants and incorporate new functionality in the thin film. The advances in ALD have helped technol. development in many areas, including semiconductor processing and magnetic disk-drive manufg. The advances in MLD are expected to advance innovations in polymeric thin-film products. Although there are remaining challenges, effective surface chem. strategies are being developed for MLD that offer the opportunity for future advances in materials and device fabrication.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD1MXisV2nt7s%253D&md5=1ca4399397f85e7d4f40afd7dfc6c800
    25. 25
      Sønsteby, H. H.; Yanguas-Gil, A.; Elam, J. W. Consistency and reproducibility in atomic layer deposition. J. Vac. Sci. Technol., A 2020, 38, 020804
      Google Scholar
      There is no corresponding record for this reference.
    26. 26
      Stassen, I.; Styles, M.; Grenci, G.; Gorp, V.; Vanderlinden, W.; Feyter, D.; Falcaro, P.; Vos, D. D.; Vereecken, P.; Ameloot, R. Chemical vapour deposition of zeolitic imidazolate framework thin films. Nat. Mater. 2016, 15, 304– 310,  DOI: 10.1038/nmat4509
      Google Scholar
      26
      Chemical vapor deposition of zeolitic imidazolate framework thin films
      Stassen, Ivo; Styles, Mark; Grenci, Gianluca; Gorp, Hans Van; Vanderlinden, Willem; Feyter, Steven De; Falcaro, Paolo; Vos, Dirk De; Vereecken, Philippe; Ameloot, Rob
      Nature Materials (2016), 15 (3), 304-310CODEN: NMAACR; ISSN:1476-1122. (Nature Publishing Group)
      A chem. vapor deposition process (MOF-CVD) that enables high-quality films of ZIF-8, a prototypical MOF material, with a uniform and controlled thickness, even on high-aspect-ratio features, is reported. The authors demonstrate how MOF-CVD enables previously inaccessible routes such as lift-off patterning and depositing MOF films on fragile features. The compatibility of MOF-CVD with existing infrastructure, both in research and prodn. facilities, will greatly facilitate MOF integration in microelectronics. MOF-CVD is the first vapor-phase deposition method for any type of microporous cryst. network solid and marks a milestone in processing such materials.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2MXitVWqtrrK&md5=10554458c52c84c69e923e31c479dbf4
    27. 27
      Ahvenniemi, E.; Karppinen, M. Atomic/molecular layer deposition: a direct gas-phase route to crystalline metal–organic framework thin films. Chem. Commun. 2016, 52, 1139– 1142,  DOI: 10.1039/c5cc08538a
      Google Scholar
      27
      Atomic/molecular layer deposition: a direct gas-phase route to crystalline metal-organic framework thin films
      Ahvenniemi, E.; Karppinen, M.
      Chemical Communications (Cambridge, United Kingdom) (2016), 52 (6), 1139-1142CODEN: CHCOFS; ISSN:1359-7345. (Royal Society of Chemistry)
      Atomic/mol. layer deposition offers the authors an elegant way of fabricating cryst. copper(II)terephthalate metal-org. framework (MOF) thin films on various substrate surfaces. The films are grown from two gaseous precursors with a digital at./mol. level control for the film thickness under relatively mild conditions in a simple and fast 1-step process.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2MXhvVGnurvL&md5=4e85fd1ee2b7e6299ca5cc2323b7f8e9
    28. 28
      Ahvenniemi, E.; Karppinen, M. In Situ Atomic/Molecular Layer-by-Layer Deposition of Inorganic–Organic Coordination Network Thin Films from Gaseous Precursors. Chem. Mater. 2016, 28, 6260– 6265,  DOI: 10.1021/acs.chemmater.6b02496
      Google Scholar
      28
      In Situ Atomic/Molecular Layer-by-Layer Deposition of Inorganic-Organic Coordination Network Thin Films from Gaseous Precursors
      Ahvenniemi, Esko; Karppinen, Maarit
      Chemistry of Materials (2016), 28 (17), 6260-6265CODEN: CMATEX; ISSN:0897-4756. (American Chemical Society)
      Cryst. inorg.-org. coordination network materials possess a property palette highly attractive for a no. of frontier applications. In many prospective applications of these materials, high-quality thin films would be required. Gas-phase thin-film techniques could potentially provide a no. of advantages over the current liq.-phase techniques for depositing such state-of-the-art hybrid thin films. The strongly emerging at./mol. layer deposition (ALD/MLD) technique in particular enables the rational fabrication of inorg.-org. thin films in a digital at./mol. layer-by-layer manner through successive gas-to-surface reactions of inorg. and org. precursors, but the resultant films have been amorphous. Here, we demonstrate the in situ ALD/MLD growth of well-cryst. calcium terephthalate (Ca-TP) coordination network thin films in a wide deposition temp. range. We moreover investigate the water absorption/desorption characteristics of the films and report attractive mech. properties for both the dry and water-intercalated films.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC28XhsVSgur7P&md5=e8a5b30b1a76c5cb61bbcaaaa20831f2
    29. 29
      Lausund, K. B.; Nilsen, O. All-gas-phase synthesis of UiO-66 through modulated atomic layer deposition. Nat. Commun. 2016, 7, 13578,  DOI: 10.1038/ncomms13578
      Google Scholar
      29
      All-gas-phase synthesis of UiO-66 through modulated atomic layer deposition
      Lausund, Kristian Blindheim; Nilsen, Ola
      Nature Communications (2016), 7 (), 13578CODEN: NCAOBW; ISSN:2041-1723. (Nature Publishing Group)
      Thin films of stable metal-org. frameworks (MOFs) such as UiO-66 have enormous application potential, for instance in microelectronics. However, all-gas-phase deposition techniques are currently not available for such MOFs. We here report on thin-film deposition of the thermally and chem. stable UiO-66 in an all-gas-phase process by the aid of at. layer deposition (ALD). Sequential reactions of ZrCl4 and 1,4-benzenedicarboxylic acid produce amorphous org.-inorg. hybrid films that are subsequently crystd. to the UiO-66 structure by treatment in acetic acid vapor. We also introduce a new approach to control the stoichiometry between metal clusters and org. linkers by modulation of the ALD growth with addnl. acetic acid pulses. An all-gas-phase synthesis technique for UiO-66 could enable implementations in microelectronics that are not compatible with solvothermal synthesis. Since this technique is ALD-based, it could also give enhanced thickness control and the possibility to coat irregular substrates with high aspect ratios.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC28XitFSns77M&md5=7ec72beaa1e506bba57b17476c62ec10
    30. 30
      Multia, J.; Karppinen, M. Atomic/Molecular Layer Deposition for Designer’s Functional Metal–Organic Materials. Adv. Mater. Interfaces 2022, 9, 2200210,  DOI: 10.1002/admi.202200210
      Google Scholar
      30
      Atomic/Molecular Layer Deposition for Designer's Functional Metal-Organic Materials
      Multia, Jenna; Karppinen, Maarit
      Advanced Materials Interfaces (2022), 9 (15), 2200210CODEN: AMIDD2; ISSN:2196-7350. (Wiley-VCH Verlag GmbH & Co. KGaA)
      Atomic layer deposition (ALD) for high-quality conformal inorg. thin films is one of the cornerstones of modern microelectronics, while mol. layer deposition (MLD) is its less-exploited counterpart for purely org. thin films. Currently, the hybrid of these two techniques, i.e., ALD/MLD, is strongly emerging as a state-of-the-art gas-phase route for designer's metal-org. thin films, e.g., for the next-generation energy technologies. The ALD/MLD literature comprises nearly 300 original journal papers covering most of the alkali and alk. earth metals, 3d transition metals, and lanthanides as the metal component and a variety of aliph., arom., and natural org. components. Some of these ALD/MLD processes yield in situ cryst. coordination-polymer- or metal-org.-framework-like structures. Another attractive aspect is that many of the metal-orgs. realized through ALD/MLD are fundamentally new materials, and even unaccessible through conventional synthesis. Here, the current state of research in the field is presented, by i) providing a comprehensive account of the ALD/MLD processes so far developed, ii) addressing the constraints/possibilities for growing in situ cryst. metal-org. films, iii) highlighting some intriguing ALD/MLD materials and their application potential, and iv) making a brief outlook to the future perspectives and challenges in the field.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BB38XhtV2hur3P&md5=f1bb8758dcdb66863c84ef136397e97b
    31. 31
      Stassen, I.; De Vos, D.; Ameloot, R. Vapor-Phase Deposition and Modification of Metal–Organic Frameworks: State-of-the-Art and Future Directions. Chem. - Eur. J. 2016, 22, 14452– 14460,  DOI: 10.1002/chem.201601921
      Google Scholar
      31
      Vapor-Phase Deposition and Modification of Metal-Organic Frameworks: State-of-the-Art and Future Directions
      Stassen, Ivo; De Vos, Dirk; Ameloot, Rob
      Chemistry - A European Journal (2016), 22 (41), 14452-14460CODEN: CEUJED; ISSN:0947-6539. (Wiley-VCH Verlag GmbH & Co. KGaA)
      A review. Materials processing, and thin-film deposition in particular, is decisive in the implementation of functional materials in industry and real-world applications. Vapor processing of materials plays a central role in manufg., esp. in electronics. Metal-org. frameworks (MOFs) are a class of nanoporous cryst. materials on the brink of breakthrough in many application areas. Vapor deposition of MOF thin films will facilitate their implementation in micro- and nanofabrication research and industries. In addn., vapor-solid modification can be used for postsynthetic tailoring of MOF properties. The authors review the recent progress in vapor processing of MOFs, summarize the underpinning chem. and principles, and highlight promising directions for future research.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC28Xht1ygsbnJ&md5=4b44a79c5fe752eea4f092aba1d259f4
    32. 32
      Stassin, T.; Rodríguez-Hermida, S.; Schrode, B.; Cruz, A. J.; Carraro, F.; Kravchenko, D.; Creemers, V.; Stassen, I.; Hauffman, T.; De Vos, D.; Falcaro, P.; Resel, R.; Ameloot, R. Vapour-phase deposition of oriented copper dicarboxylate metal–organic framework thin films. Chem. Commun. 2019, 55, 10056– 10059,  DOI: 10.1039/c9cc05161a
      Google Scholar
      32
      Vapour-phase deposition of oriented copper dicarboxylate metal-organic framework thin films
      Stassin, Timothee; Rodriguez-Hermida, Sabina; Schrode, Benedikt; Cruz, Alexander John; Carraro, Francesco; Kravchenko, Dmitry; Creemers, Vincent; Stassen, Ivo; Hauffman, Tom; De Vos, Dirk; Falcaro, Paolo; Resel, Roland; Ameloot, Rob
      Chemical Communications (Cambridge, United Kingdom) (2019), 55 (68), 10056-10059CODEN: CHCOFS; ISSN:1359-7345. (Royal Society of Chemistry)
      Copper dicarboxylate metal-org. framework films are deposited via chem. vapor deposition. Uniform films of CuBDC and CuCDC with an out-of-plane orientation and accessible porosity are obtained from the reaction of Cu and CuO with vaporized dicarboxylic acid linkers.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1MXhsVChtLjE&md5=e9fd65cebe4385d8652e0534b7c63a97
    33. 33
      Stassin, T.; Stassen, I.; Marreiros, J.; Cruz, A. J.; Verbeke, R.; Tu, M.; Reinsch, H.; Dickmann, M.; Egger, W.; Vankelecom, I. F. J.; De Vos, D. E.; Ameloot, R. Solvent-Free Powder Synthesis and MOF-CVD Thin Films of the Large-Pore Metal–Organic Framework MAF-6. Chem. Mater. 2020, 32, 1784– 1793,  DOI: 10.1021/acs.chemmater.9b03807
      Google Scholar
      33
      Solvent-Free Powder Synthesis and MOF-CVD Thin Films of the Large-Pore Metal-Organic Framework MAF-6
      Stassin, Timothee; Stassen, Ivo; Marreiros, Joao; Cruz, Alexander John; Verbeke, Rhea; Tu, Min; Reinsch, Helge; Dickmann, Marcel; Egger, Werner; Vankelecom, Ivo F. J.; De Vos, Dirk E.; Ameloot, Rob
      Chemistry of Materials (2020), 32 (5), 1784-1793CODEN: CMATEX; ISSN:0897-4756. (American Chemical Society)
      A simple solvent- and catalyst-free method is presented for the synthesis of the large-pore metal-org. framework (MOF) MAF-6 (RHO-Zn(eIm)2) based on the reaction of ZnO with 2-ethylimidazole vapor at temps. ≤ 100°C. By translating this method to a chem. vapor deposition (CVD) protocol, cryst. films of a large-pore material could be deposited for the first time entirely from the vapor phase. A combination of PALS and Kr physisorption measurements confirmed the porosity of these MOF-CVD films and the size of the MAF-6 supercages (diam. ∼2 nm), in close agreement with powder data and calcns. MAF-6 powders and films were further characterized by XRD, TGA, SEM, FTIR, PDF and EXAFS. The exceptional uptake capacity of MAF-6 in comparison to ZIF-8 is demonstrated by vapor-phase loading of a mol. larger than the ZIF-8 windows.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BB3cXhsFKisbw%253D&md5=5030e1422fc43ff76fddeaefd2dc2a76
    34. 34
      Fichtner, J.; Wu, Y.; Hitzenberger, J.; Drewello, T.; Bachmann, J. Molecular Layer Deposition from Dissolved Precursors. ECS J. Solid State Sci. Technol. 2017, 6, N171– N175,  DOI: 10.1149/2.0291709jss
      Google Scholar
      34
      Molecular Layer Deposition from Dissolved Precursors
      Fichtner, J.; Wu, Y.; Hitzenberger, J.; Drewello, T.; Bachmann, J.
      ECS Journal of Solid State Science and Technology (2017), 6 (9), N171-N175CODEN: EJSSBG; ISSN:2162-8769. (Electrochemical Society)
      We present a procedure for growing thin films of an org. polyamid material based on a cyclic repetition of two consecutive, complementary, self-limiting surface reactions. The mol. compds. that react with the surface are dissolved in an org. solvent. This new method exemplifies how at. layer deposition (ALD) and mol. layer deposition (MLD) can benefit from being transferred from the gas phase to the liq. phase, given that a broad variety of advantageous reagents are only available in dissolved form.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2sXhsFOjt7%252FN&md5=78f0c95b5bd097a4dceb8849ce0c0e34
    35. 35
      Koch, V. M.; Barr, M. K. S.; Büttner, P.; Mínguez-Bacho, I.; Döhler, D.; Winzer, B.; Reinhardt, E.; Segets, D.; Bachmann, J. A solution-based ALD route towards (CH3NH3)(PbI3) perovskite via lead sulfide films. J. Mater. Chem. A 2019, 7, 25112– 25119,  DOI: 10.1039/c9ta09715e
      Google Scholar
      35
      A solution-based ALD route towards (CH3NH3)(PbI3) perovskite via lead sulfide films
      Koch, Vanessa M.; Barr, Maissa K. S.; Buettner, Pascal; Minguez-Bacho, Ignacio; Doehler, Dirk; Winzer, Bettina; Reinhardt, Elisabeth; Segets, Doris; Bachmann, Julien
      Journal of Materials Chemistry A: Materials for Energy and Sustainability (2019), 7 (43), 25112-25119CODEN: JMCAET; ISSN:2050-7496. (Royal Society of Chemistry)
      We present a procedure to grow thin films of lead sulfide (PbS) with 'soln. Atomic Layer Deposition' (sALD), a technique which transfers the principles of ALD from the gas phase (gALD) to liq. processing. PbS thin films are successfully deposited on planar and porous substrates with a procedure that exhibits the unique ALD characteristics of self-limiting surface chem. and linear growth at room temp. The polycryst. p-type PbS films are stoichiometric and pure. They are converted to the hybrid perovskite methylammonium iodoplumbate (methylammonium lead iodide, MAPI, CH3NH3PbI3) by annealing to 150 °C in the presence of vapors from methylammonium iodide (MAI).
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1MXitVaksr%252FK&md5=ac6254f258f05eed00f4d7d47c09abd3
    36. 36
      Wu, Y.; Döhler, D.; Barr, M.; Oks, E.; Wolf, M.; Santinacci, L.; Bachmann, J. Atomic Layer Deposition from Dissolved Precursors. Nano Lett. 2015, 15, 6379– 6385,  DOI: 10.1021/acs.nanolett.5b01424
      Google Scholar
      36
      Atomic Layer Deposition from Dissolved Precursors
      Wu, Yanlin; Doehler, Dirk; Barr, Maissa; Oks, Elina; Wolf, Marc; Santinacci, Lionel; Bachmann, Julien
      Nano Letters (2015), 15 (10), 6379-6385CODEN: NALEFD; ISSN:1530-6984. (American Chemical Society)
      We establish a novel thin film deposition technique by transferring the principles of at. layer deposition (ALD) known with gaseous precursors toward precursors dissolved in a liq. An established ALD reaction behaves similarly when performed from solns. "Soln. ALD" (sALD) can coat deep pores in a conformal manner. sALD offers novel opportunities by overcoming the need for volatile and thermally robust precursors. We establish a MgO sALD procedure based on the hydrolysis of a Grignard reagent.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2MXhs1akt7fL&md5=f3e7148e495a79f0b51494eaeee13bc9
    37. 37
      Liu, J.; Lukose, B.; Shekhah, O.; Arslan, H. K.; Weidler, P.; Gliemann, H.; Bräse, S.; Grosjean, S.; Godt, A.; Feng, X.; Müllen, K.; Magdau, I.-B.; Heine, T.; Wöll, C. A novel series of isoreticular metal organic frameworks: realizing metastable structures by liquid phase epitaxy. Sci. Rep. 2012, 2, 921,  DOI: 10.1038/srep00921
      Google Scholar
      37
      A novel series of isoreticular metal organic frameworks: realizing metastable structures by liquid phase epitaxy
      Liu, Jinxuan; Lukose, Binit; Shekhah, Osama; Arslan, Hasan Kemal; Weidler, Peter; Gliemann, Hartmut; Brase, Stefan; Grosjean, Sylvain; Godt, Adelheid; Feng, Xinliang; Muellen, Klaus; Magdau, Ioan-Bogdan; Heine, Thomas; Woell, Christof
      Scientific Reports (2012), 2 (), srep00921, 5 pp.CODEN: SRCEC3; ISSN:2045-2322. (Nature Publishing Group)
      A novel class of metal org. frameworks (MOFs) was synthesized from Cu2(O2CMe)4·H2O and dicarboxylic acids using liq. phase epitaxy (LPE). The SURMOF-2 isoreticular series exhibits P4 symmetry, for the longest linker a channel-size of 3 × 3 nm2 was obtained, one of the largest values reported for any MOF so far. High quality, ab-initio electronic structure calcns. confirm the stability of a regular packing of (Cu++)2- carboxylate paddle-wheel planes with P4 symmetry and reveal, that the SURMOF-2 structures are in fact metastable, with a fairly large activation barrier for the transition to the bulk MOF-2 structures exhibiting a lower, 2-fold (P2 or C2) symmetry. The theor. calcns. also allow identifying the mechanism for the low-temp. epitaxial growth process and to explain, why a synthesis of this highly interesting, new class of high-symmetry, metastable MOFs is not possible using the conventional solvothermal process.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3sXmtVWlsw%253D%253D&md5=c3ab963fe3ee722be3cba530edd58388
    38. 38
      Shekhah, S.; Wang, H.; Kowarik, S.; Schreiber, F.; Paulus, M.; Tolan, M.; Sternemann, C.; Evers, F.; Evers, D.; Zacher, R. A.; Fischer, C.; Wöll, C. Step-by-step route for the synthesis of metal– organic frameworks. J. Am. Chem. Soc. 2007, 129, 15118– 9,  DOI: 10.1021/ja076210u
      Google Scholar
      38
      Step-by-Step Route for the Synthesis of Metal-Organic Frameworks
      Shekhah, Osama; Wang, Hui; Kowarik, Stefan; Schreiber, Frank; Paulus, Michael; Tolan, Metin; Sternemann, Christian; Evers, Florian; Zacher, Denise; Fischer, Roland A.; Woell, Christof
      Journal of the American Chemical Society (2007), 129 (49), 15118-15119CODEN: JACSAT; ISSN:0002-7863. (American Chemical Society)
      Using a novel layer-by-layer approach the authors have deposited metal-org. open frameworks (MOFs), [Cu3(BTC)2(H2O)n], based on 1,3,5-benzenetricarboxylic acid (H3BTC) and Cu(II)-ions on a COOH-terminated org. surface. The deposited layers were characterized using a no. of surface anal. techniques. XRD measurements show that the MOFs deposited using this method have the same bulk structure of HKUST-1.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD2sXhtlWmu7jI&md5=46beafc40035a456b09930a813cf7f44
    39. 39
      Arslan, H. K.; Shekhah, O.; Wohlgemuth, J.; Franzreb, M.; Fischer, R. A.; Wöll, C. High-Throughput Fabrication of Uniform and Homogenous MOF Coatings. Adv. Funct. Mater. 2011, 21, 4228– 4231,  DOI: 10.1002/adfm.201101592
      Google Scholar
      39
      High-Throughput Fabrication of Uniform and Homogeneous MOF Coatings
      Arslan, Hasan K.; Shekhah, Osama; Wohlgemuth, Jonas; Franzreb, Matthias; Fischer, Roland A.; Woell, Christof
      Advanced Functional Materials (2011), 21 (22), 4228-4231CODEN: AFMDC6; ISSN:1616-301X. (Wiley-VCH Verlag GmbH & Co. KGaA)
      We describe a novel method to produce monolithic, oriented, cryst. and highly porous coatings on solid substrates. By adopting the recently described liq.-phase epitaxy (LPE) process developed to grow metal-org. framework coatings (MOFs) on modified Au-substrates to the spray method, we have prepd. thick (μm) layers of several MOF types on modified Au-substrates, including HKUST-I and layer-pillar MOFs. The spray method not only allows such SURMOFs to be grown much faster than with the LPE-process but the dependence of layer thickness on the no. of immersion cycles also provides valuable insights into the mechanism governing the layer-by-layer MOF formation process.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3MXhtFCntrfL&md5=6b86cfdae37cbbf2a880adb49439c357
    40. 40
      Arslan, H. K.; Shekhah, O.; Wieland, D. C. F.; Paulus, M.; Sternemann, C.; Schroer, M. A.; Tiemeyer, S.; Tolan, M.; Fischer, R. A.; Wöll, C. Intercalation in layered metal–organic frameworks: reversible inclusion of an extended π-system. J. Am. Chem. Soc. 2011, 133, 8158– 8161,  DOI: 10.1021/ja2037996
      Google Scholar
      40
      Intercalation in Layered Metal-Organic Frameworks: Reversible Inclusion of an Extended π-System
      Arslan, Hasan K.; Shekhah, Osama; Wieland, D. C. Florian; Paulus, Michael; Sternemann, Christian; Schroer, Martin A.; Tiemeyer, Sebastian; Tolan, Metin; Fischer, Roland A.; Woll, Christof
      Journal of the American Chemical Society (2011), 133 (21), 8158-8161CODEN: JACSAT; ISSN:0002-7863. (American Chemical Society)
      The authors report the synthesis of layered [Zn2(bdc)2(H2O)2] and [Cu2(bdc)2(H2O)2] (bdc = 1,4-benzenedicarboxylate) metal-org. frameworks (MOF) carried out using the LPE approach employing self-assembled monolayer (SAM) modified Au-substrates. The authors obtain Cu and Zn MOF-2 structures, which have not yet been obtained using conventional, solvothermal synthesis methods. The 2-dimensional Cu2+ dimer paddle wheel planes characteristic for the MOF are strictly planar, with the planes oriented perpendicular to the substrate. Intercalation of an org. dye, DXP (N,N'-bis(2,6-dimethylphenyl)-3,4:9,10-perylentetracarboxylic diimide) leads to a reversible tilting of the planes, demonstrating the huge potential of these surface-anchored MOFs for the intercalation of large, planar mols.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3MXlvVSks7o%253D&md5=730e9689a9d5cce7dba8bdc96026f2ac
    41. 41
      Lee, J.-C.; Kim, J.-O.; Lee, H.-J.; Shin, B.; Park, S. Meniscus-Guided Control of Supersaturation for the Crystallization of High Quality Metal Organic Framework Thin Films. Chem. Mater. 2019, 31, 7377– 7385,  DOI: 10.1021/acs.chemmater.9b01996
      Google Scholar
      41
      Meniscus-Guided Control of Supersaturation for the Crystallization of High Quality Metal Organic Framework Thin Films
      Lee, Jeong-Chan; Kim, Jin-Oh; Lee, Ho-Jun; Shin, Byungha; Park, Steve
      Chemistry of Materials (2019), 31 (18), 7377-7385CODEN: CMATEX; ISSN:0897-4756. (American Chemical Society)
      Herein, meniscus-guided crystn. is introduced as a means to grow high quality metal org. framework (MOF) thin films. A meniscus was formed between a target substrate and a coating blade, and by adjusting various parameters such as substrate temp. and coating speed, supersatn. was precisely controlled, through which the crystn. process was finely tuned. Consequently, a densely packed intergrown MOF thin film with thickness tunability down to 450 nm was demonstrated. The individual crystals exhibited monodispersity in size. Interestingly, the use of a microstructured coating blade resulted in the change of crystal shape, attributed to the supersatn.-induced kinetically driven crystn. process. Our film growth process is large-area scalable, uses a miniscule amt. of soln., and has substrate versatility. Such an insight and demonstration of MOF thin-film growth via meniscus-guided crystn. will be highly useful for the development of various MOF thin-film-based devices in the future.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1MXhslWmsrbL&md5=c5cd6a8f1acbd29442776f6507662ed5
    42. 42
      Mandemaker, L. D. B.; Filez, M.; Delen, G.; Tan, H.; Zhang, X.; Lohse, D.; Weckhuysen, B. M. Time-Resolved In Situ Liquid-Phase Atomic Force Microscopy and Infrared Nanospectroscopy during the Formation of Metal–Organic Framework Thin Films. J. Phys. Chem. Lett. 2018, 9, 1838– 1844,  DOI: 10.1021/acs.jpclett.8b00203
      Google Scholar
      42
      Time-Resolved In Situ Liquid-Phase Atomic Force Microscopy and Infrared Nanospectroscopy during the Formation of Metal-Organic Framework Thin Films
      Mandemaker, Laurens D. B.; Filez, Matthias; Delen, Guusje; Tan, Huanshu; Zhang, Xuehua; Lohse, Detlef; Weckhuysen, Bert M.
      Journal of Physical Chemistry Letters (2018), 9 (8), 1838-1844CODEN: JPCLCD; ISSN:1948-7185. (American Chemical Society)
      Metal-org. framework (MOF) thin films show unmatched promise as smart membranes and photocatalytic coatings. However, their nucleation and growth resulting from intricate mol. assembly processes are not well understood yet are crucial to control the thin film properties. Here, we directly observe the nucleation and growth behavior of HKUST-1 thin films by real-time in situ AFM at different temps. in a Cu-BTC soln. In combination with ex situ IR (nano)spectroscopy, synthesis at 25 °C reveals initial nucleation of rapidly growing HKUST-1 islands surrounded by a continuously nucleating but slowly growing HKUST-1 carpet. Monitoring at 13 and 50 °C shows the strong impact of temp. on thin film formation, resulting in (partial) nucleation and growth inhibition. The nucleation and growth mechanisms as well as their kinetics provide insights to aid in future rational design of MOF thin films.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1cXmt1Cnsr0%253D&md5=66b5c6f95db3bcef902db207e4745882
    43. 43
      Haraguchi, T.; Otsubo, K.; Kitagawa, H. Emergence of Surface- and Interface-Induced Structures and Properties in Metal–Organic Framework Thin Films. Eur. J. Inorg. Chem. 2018, 2018, 1697– 1706,  DOI: 10.1002/ejic.201701234
      Google Scholar
      43
      Emergence of Surface- and Interface-Induced Structures and Properties in Metal-Organic Framework Thin Films
      Haraguchi, Tomoyuki; Otsubo, Kazuya; Kitagawa, Hiroshi
      European Journal of Inorganic Chemistry (2018), 2018 (16), 1697-1706CODEN: EJICFO; ISSN:1434-1948. (Wiley-VCH Verlag GmbH & Co. KGaA)
      A review. Metal-org. frameworks (MOFs) are of particular interest to researchers because of their structural diversity and variety of properties. MOF thin films have been intensively investigated for potential applications such as membranes, gas sensors, catalysts, etc. Although most MOF thin films have almost the same structure and properties as their bulk, some MOF thin films show remarkable structural changes and hidden properties that are not obsd. in the bulk. These phenomena would be induced by the surface and the interface. Recent improvements in thin-film fabrication methods enabled us to construct MOF thin films and discuss the properties based on the structure, thickness and cryst. orientation in detail. This microreview describes and discusses the fascinating nature of MOF thin films originating from surface/interface. This paper is expected to help with the construction of a research strategy for MOF thin films to obtain hidden structures and properties of MOFs that are not obsd. in their bulk.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1cXivFOjs7Y%253D&md5=6bc2aecf1bf2e5c5778e16d1007f130e
    44. 44
      Redel, E.; Wang, Z.; Walheim, S.; Liu, J.; Gliemann, H.; Wöll, C. On the dielectric and optical properties of surface-anchored metal-organic frameworks: A study on epitaxially grown thin films. Appl. Phys. Lett. 2013, 103, 1– 5,  DOI: 10.1063/1.4819836
      Google Scholar
      There is no corresponding record for this reference.
    45. 45
      Puurunen, R. Growth Per Cycle in Atomic Layer Deposition: A Theoretical Model. Chem. Vap. Deposition 2003, 9, 249– 257,  DOI: 10.1002/cvde.200306265
      Google Scholar
      45
      Growth per cycle in atomic layer deposition: A theoretical model
      Puurunen, Riikka L.
      Chemical Vapor Deposition (2003), 9 (5), 249-257CODEN: CVDEFX; ISSN:0948-1907. (Wiley-VCH Verlag GmbH & Co. KGaA)
      At. layer deposition (ALD) was used in advanced applications where thin layers of materials with precise thickness down to the nanometer scale are needed. Growth of materials by ALD takes place through repeating the sep., satg. reactions of at least two gaseous reactants with a solid substrate. When surface satn. is systematically used, the growth obtained per ALD reaction cycle is a well-defined quantity that depends on (i) the reactants used, (ii) the ALD processing temp., and (iii) sometimes the substrate material. A model is derived to describe the growth per cycle in ALD as a function of the chem. of the growth when compds. were used as reactants. Two main types of chemisorption may occur: (i) ligand exchange reaction of the MLn reactant with surface a groups, where ligands are removed from the surface as gaseous aL, and (ii) dissocn. or assocn., where all parts of the MLn reactant are attached to the surface. A simple math. model based on the mass balance of chemisorption relates the growth per cycle to the size of the MLn reactant and the chemisorption mechanisms involved. Steric hindrance of the ligands causes satn. of chemisorption if a limited no. of bonding sites does not cause it. Because of the steric hindrance, the growth per cycle remains less than a monolayer. The applicability of the model is illustrated through several theor. examples.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD3sXovFCkurs%253D&md5=8c1c3c359c5563692fcfa586b89484be
    46. 46
      Li, X.; Zhou, H.; Qi, F.; Niu, X.; Xu, X.; Qiu, F.; He, Y.; Pan, J.; NiPan, L. Three hidden talents in one framework: a terephthalic acid-coordinated cupric metal–organic framework with cascade cysteine oxidase- and peroxidase-mimicking activities and stimulus-responsive fluorescence for cysteine sensing. J. Mater. Chem. B 2018, 6, 6207– 6211,  DOI: 10.1039/c8tb02167h
      Google Scholar
      46
      Three hidden talents in one framework: a terephthalic acid-coordinated cupric metal-organic framework with cascade cysteine oxidase- and peroxidase-mimicking activities and stimulus-responsive fluorescence for cysteine sensing
      Li, Xin; Zhou, Hao; Qi, Fei; Niu, Xiangheng; Xu, Xuechao; Qiu, Fengxian; He, Yanfang; Pan, Jianming; Ni, Liang
      Journal of Materials Chemistry B: Materials for Biology and Medicine (2018), 6 (39), 6207-6211CODEN: JMCBDV; ISSN:2050-7518. (Royal Society of Chemistry)
      A metal-org. framework (CuBDC) that possesses cascade cysteine oxidase- and peroxidase-mimicking activities and stimulus-responsive fluorescence was designed by coordinating cupric ions with terephthalic acid. The three-in-one CuBDC provided a new and extremely convenient turn-on fluorescence platform for selective and reliable detection of cysteine.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1cXhslCjt7fF&md5=a47fcab0445e9342006696d75c83431f
    47. 47
      Dai, R.; Zhang, X.; Liu, M.; Wu, Z.; Wang, Z. Porous metal organic framework CuBDC nanosheet incorporated thin-film nanocomposite membrane for high-performance forward osmosis. J. Membr. Sci. 2019, 573, 46– 54,  DOI: 10.1016/j.memsci.2018.11.075
      Google Scholar
      47
      Porous metal organic framework CuBDC nanosheet incorporated thin-film nanocomposite membrane for high-performance forward osmosis
      Dai, Ruobin; Zhang, Xingran; Liu, Mingxian; Wu, Zhichao; Wang, Zhiwei
      Journal of Membrane Science (2019), 573 (), 46-54CODEN: JMESDO; ISSN:0376-7388. (Elsevier B.V.)
      A thin-film nanocomposite (TFN) membrane contg. compatible 2D metal-org. framework (MOF) nanofiller in the active layer was developed to improve water permeability and antifouling capacity without compromising the selectivity for forward osmosis (FO) applications. The MOF nanosheet (copper 1,4-benzenedicarboxylate nanosheets, CuBDC-NS) was successfully incorporated into polyamide (PA) active layer during the interfacial polymn., as revealed by transmission electron microscope, X-ray diffraction and XPS. The TFN membrane exhibited higher water permeability and lower reverse solute flux (Js) compared to the pristine membrane. About 50% increase in FO water flux (Jw) and 50% decrease in specific reverse solute flux (Js/Jw) were obsd. for the TFN membrane with 0.12 wt/v % CuBDC-NS compared to the control, when 1.0 M NaCl was used as draw soln. in the active-layer facing feed-soln. (AL-FS) mode. In the continuous flow test using real wastewater as the feed-soln., the TFN membrane demonstrated a higher water flux and a slower water flux decline than the pristine one. The antifouling behavior of the CuBDC incorporated TFN membrane was assocd. with the increased hydrophilicity and biocidal ability. These results highlight the potential of CuBDC-NS incorporated TFN membranes to be used in FO processes for water desalination and wastewater treatment.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1cXisVemsLfM&md5=8f4e57be911222e3038c9bff924e1a6c
    48. 48
      Elder, A. C.; Aleksandrov, A. B.; Nair, S.; Orlando, T. M. Interactions on External MOF Surfaces: Desorption of Water and Ethanol from CuBDC Nanosheets. Langmuir 2017, 33, 10153– 10160,  DOI: 10.1021/acs.langmuir.7b01987
      Google Scholar
      48
      Interactions on External MOF Surfaces: Desorption of Water and Ethanol from CuBDC Nanosheets
      Elder, Alexander C.; Aleksandrov, Alexandr B.; Nair, Sankar; Orlando, Thomas M.
      Langmuir (2017), 33 (39), 10153-10160CODEN: LANGD5; ISSN:0743-7463. (American Chemical Society)
      The external surfaces of metal-org. framework (MOF) materials are difficult to exptl. isolate due to the high porosities of these materials. MOF surface surrogates in the form of copper benzenedicarboxylate (CuBDC) nanosheets were synthesized using a bottom-up approach, and the surface interactions of water and ethanol were investigated by temp.-programmed desorption (TPD). A method of anal. of diffusion-influenced TPD was developed to measure the desorption properties of these porous materials. This approach also allows the extn. of diffusion coeffs. from TPD data. The transmission Fourier transform IR spectra, powder X-ray diffraction patterns, and TPD data indicate that water desorbs from CuBDC nanosheets with activation energies of 44 ± 2 kJ/mol at edge sites and 58 ± 1 kJ/mol at external surface and internal and pore sites. Ethanol desorbs with activation energies of 58 ± 1 kJ/mol at internal pore sites and 66 ± 0.4 kJ/mol at external surface sites. Co-adsorption of water and ethanol was also investigated. The presence of ethanol was found to inhibit the desorption of water, resulting in a water desorption process with an activation energy of 68 ± 0.7 kJ/mol.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2sXhsVKhtLfJ&md5=58693e75b161ff0971981f4fb3c084bb
    49. 49
      Wang, B.; Jin, J.; Ding, B.; Han, X.; Han, A.; Liu, J. General Approach to Metal-Organic Framework Nanosheets With Controllable Thickness by Using Metal Hydroxides as Precursors. Front. Mater. 2020, 7, 1– 7,  DOI: 10.3389/fmats.2020.00037
      Google Scholar
      There is no corresponding record for this reference.
    50. 50
      Kassem, A. A.; Abdelhamid, H. N.; Fouad, D. M.; Ibrahim, S. A. Metal-organic frameworks (MOFs) and MOFs-derived CuO@C for hydrogen generation from sodium borohydride. Int. J. Hydrogen Energy 2019, 44, 31230– 31238,  DOI: 10.1016/j.ijhydene.2019.10.047
      Google Scholar
      50
      Metal-organic frameworks (MOFs) and MOFs-derived CuO@C for hydrogen generation from sodium borohydride
      Kassem, Ahlam Azzam; Abdelhamid, Hani Nasser; Fouad, Dina M.; Ibrahim, Said A.
      International Journal of Hydrogen Energy (2019), 44 (59), 31230-31238CODEN: IJHEDX; ISSN:0360-3199. (Elsevier Ltd.)
      Hydrogen gas has been considered as one of the promising sources of energy. Thus, several strategies including the hydrolysis of hydrides have been reported for hydrogen prodn. However, effective catalysts are highly required to improve the hydrogen generation rate. Two dimensional metal-org. frameworks (copper-benzene-1,4-dicarboxylic, CuBDC), and CuBDC-derived CuO@C were synthesized, characterized and applied as catalysts for hydrogen prodn. using the hydrolysis and methanolysis of sodium borohydride (NaBH4). CuBDC, and CuO@C display hydrogen generation rate of 7620, and 7240 mlH2·g-1cat· min-1, resp. for hydrolysis. While, CuBDC offers hydrogen generation rate of 9060 mlH2·g-1cat· min-1 for methanolysis. Both catalysts required short reaction time, and showed good recyclability. The materials may open new venues for efficient catalyst for energy-based applications.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1MXitVCksbvL&md5=0f35c6738a0cf086b4c6f3f2a0974fe4
    51. 51
      Yim, C.; Jeon, S. Direct synthesis of Cu-BDC frameworks on a quartz crystal microresonator and their application to studies of n-hexane adsorption. RSC Adv. 2015, 5, 67454– 67458,  DOI: 10.1039/c5ra11686d
      Google Scholar
      52
      Direct synthesis of Cu-BDC frameworks on a quartz crystal microresonator and their application to studies of n-hexane adsorption
      Yim, Changyong; Jeon, Sangmin
      RSC Advances (2015), 5 (83), 67454-67458CODEN: RSCACL; ISSN:2046-2069. (Royal Society of Chemistry)
      We developed a facile route for synthesizing Cu-BDC frameworks using metallic copper as a metal ion source. A thin film of copper was vacuum deposited onto a quartz crystal microresonator (QCM) and converted to Cu-BDC frameworks via a solvothermal reaction. The initially superhydrophilic Cu-BDC surface became superhydrophobic upon being treated with octadecyltrichlorosilane (ODTS). Exposure of the Cu-BDC-coated quartz crystal microresonator (CuBDC-QCM) to various concns. of n-hexane vapor induced changes in the resonance frequency and Q factor of the resonator that were related to the adsorbed mass of n-hexane and the modulus of the Cu-BDC layer, resp. The mass of n-hexane vapor adsorbed on the superhydrophobic Cu-BDC layer was found to be three times that on the superhydrophilic Cu-BDC layer. Furthermore, the adsorption of n-hexane on the superhydrophobic Cu-BDC layer induced an increase in the modulus of the framework whereas the adsorption on the superhydrophilic layer induced a decrease in the modulus of the framework. These opposite changes were attributed to differences in the binding sites of n-hexane vapor inside the framework.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2MXht1KhsLzE&md5=be6701a0dd460842fab2dea964c0e567
    52. 52
      Zhang, F. Y.; Zhang, J. L.; Zhang, B. X.; Zheng, L. R.; Cheng, X. Y.; Wan, Q.; Han, B. X.; Zhang, J. CO2 controls the oriented growth of metal-organic framework with highly accessible active sites. Nat. Commun. 2020, 11, 1– 8,  DOI: 10.1038/s41467-020-15200-4
      Google Scholar
      There is no corresponding record for this reference.

  • Supporting Information

    Supporting Information

    ARTICLE SECTIONS
    Jump To

    The Supporting Information is available free of charge at https://pubs.acs.org/doi/10.1021/acs.chemmater.2c01102.

    • Detailed description of the experimental methods and used materials; additional QCM measurements; scheme of the growth of Cu-BDC SURMOF by sALD sALD setup; ; and additional characterization data of Cu-BDC (PDF)


    Terms & Conditions

    Most electronic Supporting Information files are available without a subscription to ACS Web Editions. Such files may be downloaded by article for research use (if there is a public use license linked to the relevant article, that license may permit other uses). Permission may be obtained from ACS for other uses through requests via the RightsLink permission system: http://pubs.acs.org/page/copyright/permissions.html.

PDF [ 6MB]

Pair your accounts.

Export articles to Mendeley

Get article recommendations from ACS based on references in your Mendeley library.

Pair your accounts.

Export articles to Mendeley

Get article recommendations from ACS based on references in your Mendeley library.

You’ve supercharged your research process with ACS and Mendeley!

STEP 1:
Click to create an ACS ID

Please note: If you switch to a different device, you may be asked to login again with only your ACS ID.

Please note: If you switch to a different device, you may be asked to login again with only your ACS ID.

Please note: If you switch to a different device, you may be asked to login again with only your ACS ID.

MENDELEY PAIRING EXPIRED
Your Mendeley pairing has expired. Please reconnect