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In Situ Nanoscale Investigation of Catalytic Reactions in the Liquid Phase Using Zirconia-Protected Tip-Enhanced Raman Spectroscopy Probes

Naresh Kumar
Naresh Kumar
Inorganic Chemistry and Catalysis Group, Debye Institute for Nanomaterials Science, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands
National Physical Laboratory, Hampton Road, Teddington, TW11 0LW, United Kingdom
More by Naresh Kumar
http://orcid.org/0000-0001-8953-5420
,
Caterina S. Wondergem
Caterina S. Wondergem
Inorganic Chemistry and Catalysis Group, Debye Institute for Nanomaterials Science, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands
More by Caterina S. Wondergem
,
Andrew J. Wain
Andrew J. Wain
National Physical Laboratory, Hampton Road, Teddington, TW11 0LW, United Kingdom
More by Andrew J. Wain
http://orcid.org/0000-0002-8666-6158
, and
Bert M. Weckhuysen*
Bert M. Weckhuysen
Inorganic Chemistry and Catalysis Group, Debye Institute for Nanomaterials Science, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands
*E-mail: [email protected]
More by Bert M. Weckhuysen
http://orcid.org/0000-0001-5245-1426

Cite this: J. Phys. Chem. Lett. 2019, 10, 8, 1669–1675

Publication Date (Web):March 27, 2019

https://doi.org/10.1021/acs.jpclett.8b02496

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Abstract

Tip-enhanced Raman spectroscopy (TERS) is a promising technique that enables nondestructive and label-free topographical and chemical imaging at the nanoscale. However, its scope for in situ characterization of catalytic reactions in the liquid phase has remained limited due to the lack of durable and chemically inert plasmonically active TERS probes. Herein, we present novel zirconia-protected TERS probes with 3 orders of magnitude increase in lifetime under ambient conditions compared to unprotected silver-coated probes, together with high stability in liquid media. Employing the plasmon-assisted oxidation of p-aminothiophenol as a model reaction, we demonstrate that the highly robust, durable, and chemically inert zirconia-protected TERS probes can be successfully used for nanoscale spatially resolved characterization of a photocatalytic reaction within an aqueous environment. The reported improved lifetime and stability of probes in a liquid environment extend the potential scope of TERS as a nanoanalytical tool not only to heterogeneous catalysis but also to a range of scientific disciplines in which dynamic solid–liquid interfaces play a defining role.

The rational design of novel, chemically functional nanomaterials with tailored properties relies on a deep understanding of structure–behavior relationships. This is especially poignant in the case of heterogeneous catalysis, in which the identification of active sites at spatially nonuniform solid–liquid and solid–gas interfaces under dynamic reaction conditions is key to materials and process optimization. (1,2) However, conventional analytical techniques, such as Raman, infrared (IR), ultraviolet–visible, and fluorescence spectroscopies, often lack the required sensitivity and spatial resolution to achieve this ambitious goal. (3,4) In recent years, tip-enhanced Raman spectroscopy (TERS) (Figure 1) has emerged as a potential solution to this challenge, enabling nondestructive topographical and molecular imaging of surfaces at the nanoscale. (5,6)

Figure 1. Schematic of the experimental TERS setup used in this work for spatially resolved mapping of plasmon-assisted oxidation of p-aminothiophenol (pATP) to p,p′-dimercaptoazobenzene (DMAB) over a heterogeneous Ag substrate in an aqueous environment.

In TERS, a metallic scanning probe microscopy (SPM) probe, positioned within the excitation laser spot of a Raman microscope (Figure 1), enhances the incident electric field by several orders of magnitude via a combination of localized surface plasmon resonance (LSPR) and lightening rod effects, confining the field enhancement to a region similar in size to the probe apex. This near-field approach significantly improves the sensitivity of Raman microscopy and pushes its spatial resolution far beyond the diffraction limit. This technique has been successfully used in a wide range of research areas including biology, (7) polymer blends, (8) semiconductors, (9) crystalline materials, (10) solar energy conversion, (11) nanomaterials research, (12−16) and single-molecule imaging. (17,18)

Despite the advantages of high spatial resolution and rich chemical information offered by TERS, (1,19,20) only a handful of TERS studies of catalytic reactions have been reported so far. (21−28) Furthermore, the majority of such studies have been carried out in ambient air or ultrahigh vacuum, with only a few in liquid environments, mostly limited to point spectroscopy measurements. (29−34) 2D nanoscale chemical imaging of catalytic reactions in liquids represents a key challenge but has not been achieved using TERS, primarily due to the chemical reactivity, (22,35) short lifetime, (36−39) and/or instability of TERS probes in liquids. (29,34) The chemical reactivity of metallic TERS probes is a particularly important consideration when studying catalysis in situ due to the potential for interference in the reaction under investigation. To address this issue, as well as extend the lifetime of metallic TERS probes, the use of an ultrathin coating of dielectric material such as Al₂O₃ (23,40) or SiO₂ (41) as a protective layer has been reported. However, Al₂O₃ and SiO₂ are not stable over the entire pH range, (42) limiting the conditions in which the TERS probes could be used. Furthermore, both Al₂O₃ and SiO₂ coatings only increased the lifetime of TERS probes for approximately 1 month, and although some increased stability in liquids was observed for the Al₂O₃-protected probes, (30) no TERS mapping was performed. Recently, a more effective method of protecting TERS probes using atomic layer deposition (ALD) has been reported by Huang et al., where the authors presented three different coatings, SiO₂, Al₂O₃, and TiO₂, and successfully showed that the SiO₂-coated STM-TERS probes could enhance the Raman signal from a self-assembled monolayer of thiol molecules while suppressing the signal from pyridine molecules present in solution. (43) However, TERS data was presented only for the SiO₂-coated probes, and the mechanical stability, long-term stability of plasmonic signal enhancement, and capability of 2D chemical imaging in a liquid environment was not demonstrated. Furthermore, the use of ALD to produce ultrathin dielectric coatings requires expensive experimental apparatus and time-consuming optimization of deposition conditions.

Herein, we present novel atomic force microscopy (AFM)-TERS probes with a multilayer metal coating protected using an ultrathin layer of zirconia (ZrO₂) that successfully overcome the key limitations of short lifetime, chemical inertness, and instability in a liquid environment. ZrO₂ offers excellent catalytic support properties for several reactions (44,45) and stability over the entire pH range, (42) making it especially suitable for investigating heterogeneous catalytic reactions under a wide range of conditions. Compared to ALD, the simple wet-chemical method of ZrO₂ coating developed in this work is far cheaper and could be easily implemented in any laboratory fume cupboard. Furthermore, using the novel TERS probes, we demonstrate the feasibility of mapping of a catalytic reaction over a heterogeneous metal surface in water with nanoscale spatial resolution, employing the photocatalytic oxidation of p-aminothiophenol (pATP) to p,p′-dimercaptoazobenzene (DMAB) as a model reaction (Figure 1). (23,46)

Extending the Plasmonic Lifetime of TERS Probes. Experimental details are presented in Supporting Information (SI) section S1, including development of the ZrO₂ coating procedure (Figures S1–S4). TEM measurements confirmed that the procedure was successful in coating a layer of ZrO₂ on Ag-coated TERS probes with a thickness of 1–5 nm (Figure S5). Note that the TEM measurement was conducted after using the probe for continuous TERS measurements in water for ∼2 h, which demonstrates the stability of the ZrO₂ coating. The ZrO₂ coating was also found to be stable in an aqueous environment for a long period of time and over the entire pH range (see Figure S3 and S4).

The lifetime of ZrO₂-protected TERS probes was compared with that of the unprotected (Ag-coated) TERS probes using a poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) thin film as a test sample. Plasmonic enhancement of a TERS probe can be monitored using the ratio of the Raman signal intensity in the near-field (plasmonically enhanced electric field at a TERS probe apex) and far-field (electric field in the entire excitation laser spot), which is known as “contrast” and defined as follows

Contrast = \frac{I_{TERS}}{I_{FF}} - 1

(1)

where I_TERS and I_FF are the intensities of a Raman band with the TERS probe in contact with and retracted from the sample, respectively. Time series TERS spectra recorded using unprotected and ZrO₂-protected TERS probes stored in ambient air are shown in Figure 2a,b, respectively. Additional time series spectra recorded using the unprotected and ZrO₂-protected TERS probes are presented in Figures S6 and S7. Contrast was determined using the intensity of the 1454 cm^–1 PEDOT:PSS band (ν_{sym,Cα═Cβ}) and is plotted in Figure 2c,d for the unprotected and protected probes, respectively. The near-field signal intensity of a fresh unprotected TERS probe is found to be almost 3× higher than the far-field signal, indicating a strong plasmonic enhancement of the electric field at the probe apex. However, the TERS contrast decreases rapidly by 50% of its initial value (half-life) within 4.5 h due to surface oxidation of the Ag coating in air. (36) After a rapid initial decline, the contrast decreases rather gradually by 75% in 10 h, eventually reaching 0 after 170 h of exposure to air, indicating a complete loss of plasmonic enhancement. On the other hand, although the ZrO₂-protected TERS probes exhibit a decrease in contrast of almost 50% compared to the unprotected probes (after 2 days of preparation), they show a much higher plasmonic stability; even after 140 days of exposure to the ambient environment, the TERS contrast decreased by only 43%, indicating that the plasmonic sensitivity for TERS measurements is largely preserved. The pinhole-free ZrO₂ layer likely blocks contact of the Ag coating with oxygen and moisture present in the surroundings, thereby preventing plasmonic degradation. (36) From extrapolation of the time series plot in Figure 2d, the half-life of the ZrO₂-protected TERS probes is estimated to be over 160 days. This corresponds to more than an 850× increase in lifetime compared to unprotected probes and to the best of our knowledge is the longest lifetime of any TERS probe stored under ambient conditions reported to date. Furthermore, unlike STM-based TERS, these novel ZrO₂-protected probes could be employed for nanoscale chemical mapping of a wide range of conducting and nonconducting sample surfaces using an AFM-TERS setup.

Figure 2. Time series TERS (red) and far-field Raman (blue) spectra measured from a PEDOT:PSS thin film on glass after exposing (a) unprotected TERS probes for 0, 10, and 170 h and (b) ZrO₂-protected TERS probes for 2, 33, and 140 days to the ambient environment. Integration time: 30 s. Laser power: 50 μW. Plots of TERS contrast versus exposure time of representative TERS probes to the ambient environment for measurements presented in (c) Figures 2a and S6 and (d) Figures 2b and S7. In this study, a thin film of PEDOT:PSS was chosen to measure the lifetime of the zirconia-coated TERS tips because of its high chemical stability, low surface roughness, and strong Raman signal. (30,36,40,47,48) For example, the root-mean-square surface roughness of a spin-coated PEDOT:PSS film has been shown to be 1.2 ± 0.1 nm using tapping mode AFM, confirming a smooth topography. (49) In order to further minimize the effect of surface roughness, the time series contrast plotted in Figure 2c,d was measured from an average of three TERS and far-field measurements conducted at different areas on the PEDOT:PSS thin film.

Nanoscale Mapping of a Photocatalytic Reaction in a Liquid Environment. We next used ZrO₂-protected TERS probes to demonstrate spatially resolved nanoscale characterization of a catalytic reaction within an aqueous environment. We selected the photocatalytic oxidation of pATP → DMAB as a model reaction due to the ease of monitoring using the distinct Raman bands of the azo group of DMAB, appearing in the 1140–1500 cm^–1 spectral region. (46,50) pATP → DMAB is a well-understood and well-characterized plasmon-assisted reaction wherein hot electrons generated via LSPR of metal nanoparticles cause dissociation of adsorbed oxygen under ambient conditions, facilitating oxidative dimerization. (51) On a plasmonic metal substrate, sites exhibiting a stronger LSPR are expected to act as more active catalysts. Therefore, we used a self-assembled monolayer (SAM) of pATP molecules on a heterogeneous Ag substrate containing nanostructures varying from 1 to 9 nm in height (Figure S8) as the test sample to map pATP → DMAB within a liquid environment using TERS. The Ag substrate was surface-enhanced Raman spectroscopy (SERS)-active with the 532 nm excitation laser. Characteristic a_g Raman bands of DMAB at 1142 cm^–1 (β_C–H), 1390 cm^–1 (ν_N═N), and 1437 cm^–1 (ν_N═N) could be clearly observed in the SERS spectrum of pATP adsorbed on the Ag substrate, indicating conversion to DMAB. See Figure S9 for a comparison of the SERS and Raman spectra of pATP.

We first tested the sensitivity of ZrO₂-protected TERS probes for monitoring pATP → DMAB in air and aqueous environments. For measurements in air, we placed the TERS probe in contact with the Ag substrate and carried out Raman mapping the probe apex around. Figure 3a shows the map of the 1437 cm^–1 DMAB Raman band intensity, in which a much stronger intensity is observed at the probe apex position. Comparison of average spectra measured at the TERS probe apex in Figure 3a and away from it (Figure S10) showed that the DMAB bands are visible only in the TERS spectra measured at the probe apex, indicating a strong LSPR. Furthermore, the TERS signal measured at the position of maximum intensity in Figure 3a was found to be ∼12× stronger than the SERS signal measured at the same position with the probe retracted from the sample, as shown in Figure 3c. To rule out the possibility of the zirconia-protected TERS probe interfering in the reaction at the sample, we conducted similar TERS measurements on a thin film of pATP mixed with PMMA spin-coated on a glass substrate (Figure S11). TERS spectra measured at the TERS probe apex on this sample did not show signal from any DMAB a_g Raman bands, whereas the a₁ Raman bands of pATP at 1086 and 1591 cm^–1 were enhanced by a contrast of 5.3 in the TERS near-field. This demonstrates the chemical inertness of ZrO₂-protected TERS probes for investigation of this catalytic reaction.

Figure 3. Maps of pATP → DMAB at the TERS probe apex obtained using the intensity of the 1437 cm^–1 (ν_N═N) DMAB Raman band measured from the pATP SAM on the Ag substrate in (a) air and (b) water. Integration time: 1 s. Laser power: 117 μW. Pixel size: 50 nm. TERS (red) and SERS (blue) spectra measured at the position of maximum DMAB signal in (c) Figure 3a and (d) Figure 3b, with the TERS probe in contact and retracted from the sample, respectively. Integration time: 60 s (Figure 3c) and 1 s (Figure 3d). The asymmetric shape of the reaction areas at the TERS probe apex shown in Figure 3 most likely arises from the combination of the random distribution of Ag grains at the TERS probe apex resulting from the thermal deposition of the Ag layer and the inhomogeneous and asymmetric distribution of the electromagnetic (EM) field intensity in the laser focal spot.

Next, we examined the sensitivity of the ZrO₂-protected TERS probes for monitoring pATP → DMAB in an aqueous environment. In this case, TERS measurements were performed inside of a water droplet placed on the sample surface. Interestingly, compared to the SERS measurements in air, a 210× stronger signal was observed in water, as shown in Figure S12. This is in contrast to previous reports where the far-field Raman signal of molecular SAMs on Au was found to decrease by a factor of >3 in a liquid environment compared to air due to laser focus aberrations. (25,34)

A similar loss of optical coupling in water was also observed in our TERS system during far-field Raman measurements (Figure S13). However, for the pATP SAM on the heterogeneous Ag substrate, we speculate that this effect could arise due to the red shift of the surface plasmon resonance of the SERS substrate in an aqueous environment, (52) which can lead to better matching of the surface plasmon resonance wavelength with the excitation laser, resulting in higher DMAB formation as well as a much stronger SERS signal. (53−56) However, we cannot rule out other phenomena such as surface molecular diffusion (57,58) and molecular reorientation, (59) which may be affected by the presence of an aqueous environment. A detailed understanding of this effect is beyond the scope of the present study and warrants a separate investigation, to be pursued as part of our future work. A map of the 1437 cm^–1 DMAB band intensity measured around the TERS probe apex is shown in Figure 3b. Once again, a significantly higher DMAB signal intensity is observed at the probe apex, indicating a strong LSPR. See Figure S14 for a comparison of average spectra measured at the probe apex in Figure 3b and away from it. The intensity of the TERS signal in water is found to be ∼12× stronger compared to the SERS signal measured at the same location (Figure 3d), clearly showing that the ZrO₂-protected TERS probes retain their plasmonic sensitivity in water.

Furthermore, comparison of average spectra measured at the probe apex and away from it in Figure S14 also confirms the chemical inertness rendered by ZrO₂ protection. In the Raman spectra, the ν_C–S vibrational mode at ∼1071 cm^–1 is assigned to both pATP and DMAB, whereas the ν_N═N modes at 1390 and 1437 cm^–1 and the β_C–H mode at 1142 cm^–1 are assigned exclusively to DMAB. (46) Therefore, the relative conversion of pATP to DMAB can be assessed using the ratio of the average intensity of DMAB bands (I_DMAB) to I₁₀₇₁, (50) removing the effect of fluctuations in the absolute TERS signal. (60) Calculations of I_DMAB/I₁₀₇₁ at locations P1–P4 in Figure S14 are presented in Table S1. At all four locations, I_DMAB/I₁₀₇₁ is found to be ∼1.9, indicating that the conversion of pATP to DMAB is unaffected by the presence of the ZrO₂-protected TERS probe, and it can therefore be considered as chemically noninterfering.

Finally, we performed nanoscale chemical imaging of this reaction on a Ag substrate in water. Figure 4a shows an AFM topography image of the surface, and Figure 4b shows a TERS map of the pATP → DMAB conversion, obtained using the I_DMAB/I₁₀₇₁ ratio in an area of 500 × 500 nm². The conversion exhibits a high degree of spatial heterogeneity across the Ag substrate employed, and a histogram analysis of the I_DMAB/I₁₀₇₁ ratio across this map is consistent with a broad range of catalytic activities (Figure 4c). Furthermore, the TERS map in Figure 4b exhibits a number of highly localized regions of notably high pATP → DMAB conversion. Some of these “reaction hotspots” are labeled in Figure 4b (marked as 1–3), and corresponding spectra are shown in Figure 4d. For comparison, example spectra from regions of low conversion are also shown in Figure 4d and labeled as 4–6 in Figure 4b. The locations of the most active spots can be seen in the map presented in Figure S15a, in which the contrast has been adjusted to improve visualization, and additional example spectra are shown in Figure S15b. We propose that these extremely confined regions of high conversion reflect the plasmon-assisted nature of the pATP → DMAB reaction, (51) in which LSPR at or in between individual Ag nanoparticles can confine light to a <1 nm³ volume. (61) We note that a high conversion of pATP to DMAB at a particular position on the Ag substrate could be caused by two factors: (1) strong LSPR coupling between the ZrO₂-protected TERS probe apex and the Ag substrate or (2) LSPR within the SERS hotspots present on the Ag substrate. In the current study, it is not possible to distinguish between these two contributing factors as deconvoluting the influence of the TERS probe LSPR on the surface reaction remains a challenging problem beyond the scope of this work. Line profile analysis of the high activity regions (Figure S16 and Table S2) indicates that they are typically confined to one or two pixels (100–200 nm²), consistent with nanoscale spatial resolution. The stability of the ZrO₂-protected TERS probe during TERS mapping was also assessed by comparing the first and last spectra recorded in the TERS map (see Figure S17), in which a similar signal intensity was observed.

Figure 4. (a) AFM topography image of a heterogeneous Ag substrate functionalized with pATP. (b) TERS map of the I_DMAB/I₁₀₇₁ intensity ratio for the area marked in (a). Integration time: 1 s. Laser power: 117 μW. Pixel size: 10 nm. (c) Histogram showing the % frequency of the I_DMAB/I₁₀₇₁ ratio in the pATP → DMAB TERS map in (b). (d) TERS spectra from the locations marked as 1–6 in (b) showing different degrees of conversion across the TERS map. Spectra have been normalized to the intensity of the 1071 cm^–1 band for comparison.

In summary, in this work, we have addressed the key challenges of plasmonic degradation, chemical inertness, and instability within a liquid environment of Ag-coated TERS probes by developing a novel method of protecting them with an ultrathin dielectric layer of zirconia. This successfully extends the lifetime of the probes over 850×, from a few hours to >4.5 months, while rendering them chemically inert for the investigation of catalytic reactions in liquids at the nanoscale. Finally, using these robust and durable probes, we have demonstrated mapping of a model catalytic reaction on a heterogeneous substrate within a liquid environment with nanoscale spatial resolution. This work opens up the possibility of using TERS as a nanoanalytical tool to map molecular heterogeneities and interfacial dynamics in situ in diverse areas of scientific research such as heterogeneous catalyst systems, (3) biology, (62) and electrochemistry, (63) in which nanoscale features at solid–liquid interfaces play a primary role in governing chemical behavior. Furthermore, this clear improvement in the probe lifetime and structural and chemical stability paves the way for using AFM-TERS for nondestructive, label-free, and nanoscale chemical characterization on a wide range of samples and environments.

Supporting Information

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The Supporting Information is available free of charge on the ACS Publications website at DOI: 10.1021/acs.jpclett.8b02496.

Experimental details of the TERS system, sample preparation, and preparation of TERS probes including ZrO₂ coating; time series TERS measurements of unprotected Ag-coated TERS probes in air; time series TERS measurements of ZrO₂-protected Ag-coated TERS probes in air; AFM topography of the Ag substrate; comparison of the Raman spectrum of bulk pATP and SERS spectrum of pATP adsorbed on a heterogeneous Ag substrate; analysis of pATP → DMAB at the apex of the Ag-coated TERS probe in air; chemical inertness test of the ZrO₂-protected TERS probe; comparison of pATP → DMAB SERS spectra measured in air and water environments; comparison of far-field Raman spectra measured from a polystyrene thin film on glass in air and water; analysis of pATP → DMAB at the apex of the Ag-coated TERS probe in water; further analysis of the pATP → DMAB TERS map; and comparison of the first and last spectra measured in the TERS map (PDF)

jz8b02496_si_001.pdf (1.86 MB)

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Corresponding Author
- Bert M. Weckhuysen - Inorganic Chemistry and Catalysis Group, Debye Institute for Nanomaterials Science, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands; http://orcid.org/0000-0001-5245-1426; Email: [email protected]
Authors
- Naresh Kumar - Inorganic Chemistry and Catalysis Group, Debye Institute for Nanomaterials Science, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands; National Physical Laboratory, Hampton Road, Teddington, TW11 0LW, United Kingdom; http://orcid.org/0000-0001-8953-5420
- Caterina S. Wondergem - Inorganic Chemistry and Catalysis Group, Debye Institute for Nanomaterials Science, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands
- Andrew J. Wain - National Physical Laboratory, Hampton Road, Teddington, TW11 0LW, United Kingdom; http://orcid.org/0000-0002-8666-6158
Notes
The authors declare no competing financial interest.

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B.M.W. acknowledges The Netherlands Organization for Scientific Research (NWO) for a Top research grant and the European Research Council (ERC) for an Advanced Grant (No. 321140). N.K. and A.J.W. acknowledge support from the National Measurement System of the UK Department of Business, Energy & Industry Strategy.

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This article references 63 other publications.

1
Buurmans, I. L. C.; Weckhuysen, B. M. Heterogeneities of individual catalyst particles in space and time as monitored by spectroscopy. Nat. Chem. 2012, 4 (11), 873– 886, DOI: 10.1038/nchem.1478
[Crossref], [PubMed], [CAS], Google Scholar
1
Heterogeneities of individual catalyst particles in space and time as monitored by spectroscopy
Buurmans, Inge L. C.; Weckhuysen, Bert M.
Nature Chemistry (2012), 4 (11), 873-886CODEN: NCAHBB; ISSN:1755-4330. (Nature Publishing Group)
A review. Recent years have witnessed the introduction of spatiotemporal spectroscopy for the characterization of catalysts at work at previously unattainable resoln. and sensitivity. They have revealed that heterogeneous catalysts are more heterogeneous than often expected. Dynamic changes in the nature of active sites, such as their distribution and accessibility, occur both between and within particles. Scientists now have micro- and nanospectroscopic methods at hand to improve the understanding of catalyst heterogeneities and exploit them in catalyst design. Here we review the latest developments within this lively field. The trends include detection of single particles or mols., super-resoln. imaging, the transition from two- to three-dimensional imaging, selective staining, integration of spectroscopy with electron microscopy or scanning probe methods, and measuring under realistic reaction conditions. Such exptl. approaches change the hitherto somewhat static picture of heterogeneous catalysis into one that acknowledges that catalysts behave almost like living objects - explaining why many characterization methods from the life sciences are being incorporated into catalysis research.
>> More from SciFinder ^®
https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC38XhsFCgurvI&md5=bb70ab2dcf7b392b8b9a82f7935d105e
2
Rothenberg, G. Catalysis: Concepts and Green Applications, 2nd ed.; Wiley-VCH: Weinheim, Germany, 2017.
Google Scholar
There is no corresponding record for this reference.
3
Weckhuysen, B. M. In situ Spectroscopy of Catalysts; American Scientific Publishers: Stevenson Ranch, 2004.
Google Scholar
There is no corresponding record for this reference.
4
Mestl, G. In situ Raman spectroscopy - a valuable tool to understand operating catalysts. J. Mol. Catal. A: Chem. 2000, 158 (1), 45– 65, DOI: 10.1016/S1381-1169(00)00042-X
[Crossref], [CAS], Google Scholar
4
In situ Raman spectroscopy - a valuable tool to understand operating catalysts
Mestl, G.
Journal of Molecular Catalysis A: Chemical (2000), 158 (1), 45-65CODEN: JMCCF2; ISSN:1381-1169. (Elsevier Science B.V.)
A review with 49 refs.; laser Raman spectroscopy (LRS) is one of the most powerful tools for the in situ study of catalytic materials and surfaces under working conditions. Raman characterizations can be carried out at temps. as high as 1000 K and in controlled atmospheres. Modern high light-throughput spectrometers permit the recording of the whole spectral range from 100 to 4000 cm-1 at once and time resolns. in the subsecond regime for materials with high Raman cross-sections. Transient temp. or pressure response studies, e.g. pulse expts. with isotope labels, are thus possible, and kinetic and spectroscopic characteristics can be related. Modern quartz fiber optics render possible easy spectroscopic access to catalytic reactors of defined and well characterized operation conditions. Quant. relation of real catalytic steady state operation, e.g. catalytic activity and selectivity, to changes in the catalyst structure is thus made possible. Several in situ LRS studies are discussed including the characterization of supported and unsupported Mo-based catalysts, confocal Raman microspectroscopy of mixed MoVW oxide catalysts, oxygen exchange in Sb2O3/MoO3 oxide phys. mixts. elucidating the catalytic synergy effects, and active surface intermediates during oxidative coupling of methane, and NO and N2O decompn. over Ba/MgO catalysts related to the catalytic reaction via transient pressure step expts.
>> More from SciFinder ^®
https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD3cXkvFyltLg%253D&md5=daaf1c17a7183313908fe04dc6527a8b
5
Verma, P. Tip-enhanced Raman spectroscopy: Technique and recent advances. Chem. Rev. 2017, 117 (9), 6447– 6466, DOI: 10.1021/acs.chemrev.6b00821
[ACS Full Text ], [CAS], Google Scholar
5
Tip-Enhanced Raman Spectroscopy: Technique and Recent Advances
Verma, Prabhat
Chemical Reviews (Washington, DC, United States) (2017), 117 (9), 6447-6466CODEN: CHREAY; ISSN:0009-2665. (American Chemical Society)
A review. This review discusses a relatively new technique for optical nanoimaging at visible wavelength, known as tip-enhanced Raman spectroscopy (TERS). This technique relies on the enhancement and spatial confinement of light in the close vicinity of the apex of a plasmonic nanotip. The plasmonic nanotip can be positioned on the sample and controlled by a suitable scanning probe microscopy, such as at. force microscopy or scanning tunneling microscopy. By raster scanning the nanotip, one can obtain nanoimages with high spatial resoln. While enhancement helps measuring weak phonon modes from a tiny vol. of the sample, confinement delivers extremely high spatial resoln. in nanoimaging. We will discuss the technique of TERS in more detail with several applications and review the recent advances.
>> More from SciFinder ^®
https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2sXmslyhu78%253D&md5=0ebe86df82956cfc4b82af6b150541a5
6
Deckert-Gaudig, T.; Taguchi, A.; Kawata, S.; Deckert, V. Tip-enhanced Raman spectroscopy–from early developments to recent advances. Chem. Soc. Rev. 2017, 46 (13), 4077– 4110, DOI: 10.1039/C7CS00209B
[Crossref], Google Scholar
There is no corresponding record for this reference.
7
Kumar, N.; Drozdz, M. M.; Jiang, H.; Santos, D. M.; Vaux, D. J. Nanoscale mapping of newly-synthesised phospholipid molecules in a biological cell using tip-enhanced Raman spectroscopy. Chem. Commun. 2017, 53 (16), 2451– 2454, DOI: 10.1039/C6CC10226C
[Crossref], [PubMed], [CAS], Google Scholar
7
Nanoscale mapping of newly-synthesised phospholipid molecules in a biological cell using tip-enhanced Raman spectroscopy
Kumar, Naresh; Drozdz, Marek M.; Jiang, Haibo; Santos, Daniela M.; Vaux, David J.
Chemical Communications (Cambridge, United Kingdom) (2017), 53 (16), 2451-2454CODEN: CHCOFS; ISSN:1359-7345. (Royal Society of Chemistry)
Nanoscale chem. mapping of newly-synthesized phospholipid mols. inside a mammalian cell is demonstrated using tip-enhanced Raman spectroscopy (TERS) for the first time using mouse pre-adipocyte cells as a model system. Newly-synthesized membrane phospholipid distribution within a pre-adipocyte cell is mapped with <20 nm spatial resoln., overcoming the diffraction limit of confocal Raman spectroscopy via plasmonic enhancement of Raman signals at a TERS tip-apex.
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Yeo, B. S.; Amstad, E.; Schmid, T.; Stadler, J.; Zenobi, R. Nanoscale probing of a polymer-blend thin film with tip-enhanced Raman spectroscopy. Small 2009, 5 (8), 952– 960, DOI: 10.1002/smll.200801101
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Nanoscale probing of a polymer-blend thin film with tip-enhanced raman spectroscopy
Yeo, Boon-Siang; Amstad, Esther; Schmid, Thomas; Stadler, Johannes; Zenobi, Renato
Small (2009), 5 (8), 952-960CODEN: SMALBC; ISSN:1613-6810. (Wiley-VCH Verlag GmbH & Co. KGaA)
Fundamental advances have been made in the spatially resolved chem. anal. of polymer thin films. Tip-enhanced Raman spectroscopy (TERS) is used to investigate the surface compn. of a mixed polyisoprene (PI) and polystyrene (PS) thin film. High-quality TER spectra are collected from these nonresonant Raman-active polymers. A wealth of structural information is obtained, some of which cannot be acquired with conventional anal. techniques. PI and PS are identified at the surface and subsurface, resp. Differences in the band intensities suggest strongly that the polymer layers are not uniformly thick, and that nanopores are present under the film surface. The continuous PS subsurface layer and subsurface nanopores have hitherto not been identified. These data are obtained with nanometer spatial resoln. Confocal far-field Raman spectroscopy and XPS are employed to corroborate some of the results. With routine prodn. of highly enhancing TERS tips expected in the near future, it is predicted that TERS will be of great use for the rigorous chem. anal. of polymer and other composite systems with nanometer spatial resoln.
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Lucia, A.; Cacioppo, O. A.; Iulianella, E.; Latessa, L.; Moccia, G.; Passeri, D.; Rossi, M. Capability of tip-enhanced Raman spectroscopy about nanoscale analysis of strained silicon for semiconductor devices production. Appl. Phys. Lett. 2017, 110 (10), 103105, DOI: 10.1063/1.4978261
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Berweger, S.; Neacsu, C. C.; Mao, Y.; Zhou, H.; Wong, S. S.; Raschke, M. B. Optical nanocrystallography with tip-enhanced phonon Raman spectroscopy. Nat. Nanotechnol. 2009, 4 (8), 496– 499, DOI: 10.1038/nnano.2009.190
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Optical nanocrystallography with tip-enhanced phonon Raman spectroscopy
Berweger, Samuel; Neacsu, Catalin C.; Mao, Yuanbing; Zhou, Hongjun; Wong, Stanislaus S.; Raschke, Markus B.
Nature Nanotechnology (2009), 4 (8), 496-499CODEN: NNAABX; ISSN:1748-3387. (Nature Publishing Group)
Conventional phonon Raman spectroscopy is a powerful exptl. technique for the study of cryst. solids that allows crystallog., phase and domain identification on length scales down to ∼1 μm. Here we demonstrate the extension of tip-enhanced Raman spectroscopy to optical crystallog. on the nanoscale by identifying intrinsic ferroelec. domains of individual BaTiO3 nanocrystals through selective probing of different transverse optical phonon modes in the system. The technique is generally applicable for most crystal classes, and for example, structural inhomogeneities, phase transitions, ferroic order and related finite-size effects occurring on nanometer length scales can be studied with simultaneous symmetry selectivity, nanoscale sensitivity and chem. specificity.
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Kumar, N.; Zoladek-Lemanczyk, A.; Guilbert, A. A.; Su, W.; Tuladhar, S. M.; Kirchartz, T.; Schroeder, B. C.; McCulloch, I.; Nelson, J.; Roy, D. Simultaneous topographical, electrical and optical microscopy of optoelectronic devices at the nanoscale. Nanoscale 2017, 9 (8), 2723– 2731, DOI: 10.1039/C6NR09057E
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Simultaneous topographical, electrical and optical microscopy of optoelectronic devices at the nanoscale
Kumar, Naresh; Zoladek-Lemanczyk, Alina; Guilbert, Anne A. Y.; Su, Weitao; Tuladhar, Sachetan M.; Kirchartz, Thomas; Schroeder, Bob C.; McCulloch, Iain; Nelson, Jenny; Roy, Debdulal; Castro, Fernando A.
Nanoscale (2017), 9 (8), 2723-2731CODEN: NANOHL; ISSN:2040-3372. (Royal Society of Chemistry)
Novel optoelectronic devices rely on complex nanomaterial systems where the nanoscale morphol. and local chem. compn. are crit. to performance. However, the lack of anal. techniques that can directly probe these structure-property relationships at the nanoscale presents a major obstacle to device development. In this work, we present a novel method for non-destructive, simultaneous mapping of the morphol., chem. compn. and photoelec. properties with <20 nm spatial resoln. by combining plasmonic optical signal enhancement with elec.-mode scanning probe microscopy. We demonstrate that this combined approach offers subsurface sensitivity that can be exploited to provide mol. information with a nanoscale resoln. in all three spatial dimensions. By applying the technique to an org. solar cell device, we show that the inferred surface and subsurface compn. distribution correlates strongly with the local photocurrent generation and explains macroscopic device performance. For instance, the direct measurement of fullerene phase purity can distinguish between high purity aggregates that lead to poor performance and lower purity aggregates (fullerene intercalated with polymer) that result in strong photocurrent generation and collection. We show that the reliable detn. of the structure-property relationship at the nanoscale can remove ambiguity from macroscopic device data and support the identification of the best routes for device optimization. The multi-parameter measurement approach demonstrated herein is expected to play a significant role in guiding the rational design of nanomaterial-based optoelectronic devices, by opening a new realm of possibilities for advanced investigation via the combination of nanoscale optical spectroscopy with a whole range of scanning probe microscopy modes.
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Yano, T.-a.; Ichimura, T.; Kuwahara, S.; H’Dhili, F.; Uetsuki, K.; Okuno, Y.; Verma, P.; Kawata, S. Tip-enhanced nano-Raman analytical imaging of locally induced strain distribution in carbon nanotubes. Nat. Commun. 2013, 4, 2592, DOI: 10.1038/ncomms3592
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Tip-enhanced nano-Raman analytical imaging of locally induced strain distribution in carbon nanotubes
Yano Taka-Aki; Ichimura Taro; Kuwahara Shota; H'dhili Fekhra; Uetsuki Kazumasa; Okuno Yoshito; Verma Prabhat; Kawata Satoshi
Nature communications (2013), 4 (), 2592 ISSN:.
Tip-enhanced Raman scattering microscopy is a powerful technique for analysing nanomaterials at high spatial resolution far beyond the diffraction limit of light. However, imaging of intrinsic properties of materials such as individual molecules or local structures has not yet been achieved even with a tip-enhanced Raman scattering microscope. Here we demonstrate colour-coded tip-enhanced Raman scattering imaging of strain distribution along the length of a carbon nanotube. The strain is induced by dragging the nanotube with an atomic force microscope tip. A silver-coated nanotip is employed to enhance and detect Raman scattering from specific locations of the nanotube directly under the tip apex, representing deformation of its molecular alignment because of the existence of local strain. Our technique remarkably provides an insight into localized variations of structural properties in nanomaterials, which could prove useful for a variety of applications of carbon nanotubes and other nanomaterials as functional devices and materials.
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Su, W.; Kumar, N.; Dai, N.; Roy, D. Nanoscale mapping of intrinsic defects in single-layer graphene using tip-enhanced Raman spectroscopy. Chem. Commun. 2016, 52 (53), 8227– 8230, DOI: 10.1039/C6CC01990K
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Nanoscale mapping of intrinsic defects in single-layer graphene using tip-enhanced Raman spectroscopy
Su, Weitao; Kumar, Naresh; Dai, Ning; Roy, Debdulal
Chemical Communications (Cambridge, United Kingdom) (2016), 52 (53), 8227-8230CODEN: CHCOFS; ISSN:1359-7345. (Royal Society of Chemistry)
Non-gap mode tip-enhanced Raman spectroscopy (TERS) is used for the first time to successfully map the intrinsic defects in single-layer graphene with 20 nm spatial resoln. The nanoscale Raman mapping is enabled by an unprecedented near-field to far-field signal contrast of 8.5 at the Ag-coated TERS tip-apex. These results demonstrate the potential of TERS for characterization of defects in single-layer graphene-based devices at the nanometer length-scale.
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Su, W.; Kumar, N.; Mignuzzi, S.; Crain, J.; Roy, D. Nanoscale mapping of excitonic processes in single-layer MoS2 using tip-enhanced photoluminescence microscopy. Nanoscale 2016, 8 (20), 10564– 10569, DOI: 10.1039/C5NR07378B
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Nanoscale mapping of excitonic processes in single-layer MoS2 using tip-enhanced photoluminescence microscopy
Su, Weitao; Kumar, Naresh; Mignuzzi, Sandro; Crain, Jason; Roy, Debdulal
Nanoscale (2016), 8 (20), 10564-10569CODEN: NANOHL; ISSN:2040-3372. (Royal Society of Chemistry)
In two-dimensional (2D) semiconductors, photoluminescence originating from recombination processes involving neutral electron-hole pairs (excitons) and charged complexes (trions) is strongly affected by the localized charge transfer due to inhomogeneous interactions with the local environment and surface defects. Herein, we demonstrate the first nanoscale mapping of excitons and trions in single-layer MoS2 using the full spectral information obtained via tip-enhanced photoluminescence (TEPL) microscopy along with tip-enhanced Raman spectroscopy (TERS) imaging of a 2D flake. Finally, we show the mapping of the PL quenching center in single-layer MoS2 with an unprecedented spatial resoln. of 20 nm. In addn., our research shows that unlike in aperture-scanning near field microscopy, preferential exciton emission mapping at the nanoscale using TEPL and Raman mapping using TERS can be obtained simultaneously using this method that can be used to correlate the structural and excitonic properties.
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Su, W.; Kumar, N.; Krayev, A.; Chaigneau, M. In situ topographical chemical and electrical imaging of carboxyl graphene oxide at the nanoscale. Nat. Commun. 2018, 9 (1), 2891, DOI: 10.1038/s41467-018-05307-0
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In situ topographical chemical and electrical imaging of carboxyl graphene oxide at the nanoscale
Su Weitao; Su Weitao; Kumar Naresh; Kumar Naresh; Krayev Andrey; Chaigneau Marc
Nature communications (2018), 9 (1), 2891 ISSN:.
Visualising the distribution of structural defects and functional groups present on the surface of two-dimensional (2D) materials such as graphene oxide challenges the sensitivity and spatial resolution of the most advanced analytical techniques. Here we demonstrate mapping of functional groups on a carboxyl-modified graphene oxide (GO-COOH) surface with a spatial resolution of ≈10 nm using tip-enhanced Raman spectroscopy (TERS). Furthermore, we extend the capability of TERS by measuring local electronic properties in situ, in addition to the surface topography and chemical composition. Our results reveal that the Fermi level at the GO-COOH surface decreases as the ID/IG ratio increases, correlating the local defect density with the Fermi level at nanometre length-scales. The in situ multi-parameter microscopy demonstrated in this work significantly improves the accuracy of nanoscale surface characterisation, eliminates measurement artefacts, and opens up the possibilities for characterising optoelectronic devices based on 2D materials under operational conditions.
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Kumar, N.; Su, W.; Castro, F. A.; Weckhuysen, B. M. Tip-enhanced Raman spectroscopy applications: From graphene to heterogeneous catalysis. Proc. SPIE Nanoscience & Engineering VI 2018, 10726, 1072608, DOI: 10.1117/12.2322188
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Zhang, R.; Zhang, Y.; Dong, Z. C.; Jiang, S.; Zhang, C.; Chen, L. G.; Zhang, L.; Liao, Y.; Aizpurua, J.; Luo, Y.; Yang, J. L.; Hou, J. G. Chemical mapping of a single molecule by plasmon-enhanced Raman scattering. Nature 2013, 498 (7452), 82– 86, DOI: 10.1038/nature12151
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Chemical mapping of a single molecule by plasmon-enhanced Raman scattering
Zhang, R.; Zhang, Y.; Dong, Z. C.; Jiang, S.; Zhang, C.; Chen, L. G.; Zhang, L.; Liao, Y.; Aizpurua, J.; Luo, Y.; Yang, J. L.; Hou, J. G.
Nature (London, United Kingdom) (2013), 498 (7452), 82-86CODEN: NATUAS; ISSN:0028-0836. (Nature Publishing Group)
Visualizing individual mols. with chem. recognition is a longstanding target in catalysis, mol. nanotechnol. and biotechnol. Mol. vibrations provide a valuable fingerprint' for such identification. Vibrational spectroscopy based on tip-enhanced Raman scattering allows us to access the spectral signals of mol. species very efficiently via the strong localized plasmonic fields produced at the tip apex. However, the best spatial resoln. of the tip-enhanced Raman scattering imaging is still limited to 3-15 nm, which is not adequate for resolving a single mol. chem. Here we demonstrate Raman spectral imaging with spatial resoln. below one nanometer, resolving the inner structure and surface configuration of a single mol. This is achieved by spectrally matching the resonance of the nanocavity plasmon to the mol. vibronic transitions, particularly the downward transition responsible for the emission of Raman photons. This matching is made possible by the extremely precise tuning capability provided by scanning tunneling microscopy. Exptl. evidence suggests that the highly confined and broadband nature of the nanocavity plasmon field in the tunnelling gap is essential for ultrahigh-resoln. imaging through the generation of an efficient double-resonance enhancement for both Raman excitation and Raman emission. Our technique not only allows for chem. imaging at the single-mol. level, but also offers a new way to study the optical processes and photochem. of a single mol.
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Zrimsek, A. B.; Chiang, N.; Mattei, M.; Zaleski, S.; McAnally, M. O.; Chapman, C. T.; Henry, A.-I.; Schatz, G. C.; Van Duyne, R. P. Single-molecule chemistry with surface-and tip-enhanced Raman spectroscopy. Chem. Rev. 2017, 117 (11), 7583– 7613, DOI: 10.1021/acs.chemrev.6b00552
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Kim, H.; Kosuda, K. M.; Van Duyne, R. P.; Stair, P. C. Resonance Raman and surface- and tip-enhanced Raman spectroscopy methods to study solid catalysts and heterogeneous catalytic reactions. Chem. Soc. Rev. 2010, 39 (12), 4820– 4844, DOI: 10.1039/c0cs00044b
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Resonance Raman and surface- and tip-enhanced Raman spectroscopy methods to study solid catalysts and heterogeneous catalytic reactions
Kim, Hacksung; Kosuda, Kathryn M.; Van Duyne, Richard P.; Stair, Peter C.
Chemical Society Reviews (2010), 39 (12), 4820-4844CODEN: CSRVBR; ISSN:0306-0012. (Royal Society of Chemistry)
A review. Resonance Raman (RR) spectroscopy has several advantages over the normal Raman spectroscopy (RS) widely used for in situ characterization of solid catalysts and catalytic reactions. Compared with RS, RR can provide much higher sensitivity and selectivity in detecting catalytically-significant surface metal oxides. RR can potentially give useful information on the nature of excited states relevant to photocatalysis and on the anharmonic potential of the ground state. In this crit. review a detailed discussion is presented on several types of RR exptl. systems, 3 distinct sources of so-called Raman (fluorescence) background, detection limits for RR compared to other techniques (EXAFS, PM-IRAS, SFG), and 3 well-known methods to assign UV-vis absorption bands and a band-specific unified method that is derived mainly from RR results. In addn., the virtues and challenges of surface-enhanced Raman spectroscopy (SERS) are discussed for detecting mol. adsorbates at catalytically relevant interfaces. Tip-enhanced Raman spectroscopy (TERS), which is a combination of SERS and near-field scanning probe microscopy and has the capability of probing mol. adsorbates at specific catalytic sites with an enormous surface sensitivity and nanometer spatial resoln., is also reviewed.
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Hartman, T.; Wondergem, C. S.; Kumar, N.; van den Berg, A.; Weckhuysen, B. M. Surface-and tip-enhanced Raman spectroscopy in catalysis. J. Phys. Chem. Lett. 2016, 7 (8), 1570– 1584, DOI: 10.1021/acs.jpclett.6b00147
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Surface- and Tip-Enhanced Raman Spectroscopy in Catalysis
Hartman, Thomas; Wondergem, Caterina S.; Kumar, Naresh; van den Berg, Albert; Weckhuysen, Bert M.
Journal of Physical Chemistry Letters (2016), 7 (8), 1570-1584CODEN: JPCLCD; ISSN:1948-7185. (American Chemical Society)
A review; surface- and tip-enhanced Raman spectroscopy (SERS and TERS) techniques exhibit highly localized chem. sensitivity, making them ideal for studying chem. reactions, including processes at catalytic surfaces. Catalyst structures, adsorbates, and reaction intermediates can be obsd. in low quantities at hot spots where electromagnetic fields are the strongest, providing ample opportunities to elucidate reaction mechanisms. Moreover, under ideal measurement conditions, it can even be used to trigger chem. reactions. However, factors such as substrate instability and insufficient signal enhancement still limit the applicability of SERS and TERS in the field of catalysis. By the use of sophisticated colloidal synthesis methods and advanced techniques, such as shell-isolated nanoparticle-enhanced Raman spectroscopy, these challenges could be overcome.
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Domke, K. F.; Pettinger, B. In situ discrimination between axially complexed and ligand-free Co porphyrin on Au(111) with tip-enhanced Raman spectroscopy. ChemPhysChem 2009, 10 (11), 1794– 1798, DOI: 10.1002/cphc.200900182
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In Situ Discrimination between Axially Complexed and Ligand-Free Co Porphyrin on Au(111) with Tip-Enhanced Raman Spectroscopy
Domke, Katrin F.; Pettinger, Bruno
ChemPhysChem (2009), 10 (11), 1794-1798CODEN: CPCHFT; ISSN:1439-4235. (Wiley-VCH Verlag GmbH & Co. KGaA)
Simultaneous chem. and topog. information about cobalt tetraphenyl-porphyrin (CoTPP) adlayers formed on a Au(111) single crystal is obtained with tip-enhanced Raman (TER) spectroscopy. We distinguish in situ between sample areas covered with an ordered adlayer of CoTPP and areas covered with a spontaneously formed disordered phase. The Raman vibrational fingerprints collected from the nanometer-sized near-field region just below a scanning tunnelling microscope (STM) tip are correlated with the adsorbate structures seen in the STM images. We assign the TER spectral features of the disordered phase to CoTPP complexes with CO and/or NO axial ligands, whereas the TER spectrum obtained from the ordered phase does not show any indication of addnl. axial complexation of CoTPP.
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van Schrojenstein Lantman, E. M.; Deckert-Gaudig, T.; Mank, A. J. G.; Deckert, V.; Weckhuysen, B. M. Catalytic processes monitored at the nanoscale with tip-enhanced Raman spectroscopy. Nat. Nanotechnol. 2012, 7 (9), 583– 586, DOI: 10.1038/nnano.2012.131
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Catalytic processes monitored at the nanoscale with tip-enhanced Raman spectroscopy
van Schrojenstein Lantman, Evelien M.; Deckert-Gaudig, Tanja; Mank, Arjan J. G.; Deckert, Volker; Weckhuysen, Bert M.
Nature Nanotechnology (2012), 7 (9), 583-586CODEN: NNAABX; ISSN:1748-3387. (Nature Publishing Group)
Heterogeneous catalysts play a pivotal role in the chem. industry, but acquiring mol. insights into functioning catalysts remains a significant challenge. Recent advances in micro-spectroscopic approaches have allowed spatiotemporal information to be obtained on the dynamics of single active sites and the diffusion of single mols. However, these methods lack nanometer-scale spatial resoln. and/or require the use of fluorescent labels. Here, we show that time-resolved tip-enhanced Raman spectroscopy can monitor photocatalytic reactions at the nanoscale. We use a silver-coated at. force microscope tip to both enhance the Raman signal and to act as the catalyst. The tip is placed in contact with a self-assembled monolayer of p-nitrothiophenol mols. adsorbed on gold nanoplates. A photocatalytic redn. process is induced at the apex of the tip with green laser light, while red laser light is used to monitor the transformation process during the reaction. This dual-wavelength approach can also be used to observe other mol. effects such as monolayer diffusion.
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Kumar, N.; Stephanidis, B.; Zenobi, R.; Wain, A.; Roy, D. Nanoscale mapping of catalytic activity using tip-enhanced Raman spectroscopy. Nanoscale 2015, 7 (16), 7133– 7137, DOI: 10.1039/C4NR07441F
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Nanoscale mapping of catalytic activity using tip-enhanced Raman spectroscopy
Kumar, N.; Stephanidis, B.; Zenobi, R.; Wain, A. J.; Roy, D.
Nanoscale (2015), 7 (16), 7133-7137CODEN: NANOHL; ISSN:2040-3372. (Royal Society of Chemistry)
Chem.mapping of a photocatalytic reaction with nanoscale spatial resoln.is demonstrated for the first time using tip-enhanced Raman spectroscopy (TERS). An ultrathin alumina film applied to the Ag-coated TERS tip blocks catalytic interference while maintaining near-field electromagnetic enhancement, thus enabling spectroscopic imaging of catalytic activity on nanostructured Ag surfaces.
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Zhong, J.-H.; Jin, X.; Meng, L.; Wang, X.; Su, H.-S.; Yang, Z.-L.; Williams, C. T.; Ren, B. Probing the electronic and catalytic properties of a bimetallic surface with 3 nm resolution. Nat. Nanotechnol. 2016, 12 (2), 132– 136, DOI: 10.1038/nnano.2016.241
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Martín Sabanés, N.; Driessen, L. M.; Domke, K. F. Versatile side-illumination geometry for tip-enhanced Raman spectroscopy at solid/liquid interfaces. Anal. Chem. 2016, 88 (14), 7108– 7114, DOI: 10.1021/acs.analchem.6b01080
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Versatile Side-Illumination Geometry for Tip-Enhanced Raman Spectroscopy at Solid/Liquid Interfaces
Martin Sabanes, Natalia; Driessen, Leonie M. A.; Domke, Katrin F.
Analytical Chemistry (Washington, DC, United States) (2016), 88 (14), 7108-7114CODEN: ANCHAM; ISSN:0003-2700. (American Chemical Society)
In situ characterization of surfaces with tip-enhanced Raman spectroscopy (TERS) provides chem. and topog. information with high spatial resoln. and submonolayer chem. sensitivity. To further the versatility of the TERS approach toward more complex systems such as biol. membranes or energy conversion devices, adaptation of the technique to solid/liq. working conditions is essential. Here, we present a home-built side-illumination TERS setup design based on a com. scanning tunneling microscope (STM) as a versatile, cost-efficient soln. for TERS at solid/liq. interfaces. Interestingly, the results obtained from showcase resonant dye and nonresonant thiophenol monolayers adsorbed on Au single crystals suggest that excitation beam aberrations due to the presence of the aq. phase are small enough not to limit TER signal detection. The STM parameters are found to play a crucial role for solid/liq. TERS sensitivity. Raman enhancement factors of 105 at μW laser power demonstrate the great potential the presented exptl. configuration holds for solid/liq. interfacial spectroscopic studies.
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Martín Sabanés, N.; Ohto, T.; Andrienko, D.; Nagata, Y.; Domke, K. F. Electrochemical TERS elucidates potential-induced molecular reorientation of adenine/Au(111). Angew. Chem., Int. Ed. 2017, 56 (33), 9796– 9801, DOI: 10.1002/anie.201704460
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Electrochemical TERS Elucidates Potential-Induced Molecular Reorientation of Adenine/Au(111)
Martin Sabanes, Natalia; Ohto, Tatsuhiko; Andrienko, Denis; Nagata, Yuki; Domke, Katrin F.
Angewandte Chemie, International Edition (2017), 56 (33), 9796-9801CODEN: ACIEF5; ISSN:1433-7851. (Wiley-VCH Verlag GmbH & Co. KGaA)
Electrochem. surface activity arises from the interaction and geometric arrangement of mols. at electrified interfaces. The authors present a novel electrochem. tip-enhanced Raman spectroscope that can access the vibrational fingerprint of <100 small, nonresonant mols. adsorbed at atomically flat Au electrodes to study their adsorption geometry and chem. reactivity as a function of the applied potential. Combining exptl. and simulation data for adenine/Au(111), protonated physisorbed adenine adopts a tilted orientation at low potentials, whereas it is vertically adsorbed around the potential of zero charge. Further potential increase induces adenine deprotonation and reorientation to a planar configuration. The extension of EC-TERS to the study of adsorbate reorientation significantly broadens the applicability of this advanced spectroelectrochem. tool for the nanoscale characterization of a full range of electrochem. interfaces.
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Mattei, M.; Kang, G.; Goubert, G.; Chulhai, D. V.; Schatz, G. C.; Jensen, L.; Van Duyne, R. P. Tip-enhanced Raman voltammetry: Coverage dependence and quantitative modeling. Nano Lett. 2017, 17 (1), 590– 596, DOI: 10.1021/acs.nanolett.6b04868
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Kumar, N.; Kalirai, S.; Wain, A. J.; Weckhuysen, B. M. Nanoscale chemical imaging of a single catalyst particle with tip-enhanced fluorescence microscopy. ChemCatChem 2019, 11 (1), 417– 423, DOI: 10.1002/cctc.201801023
[Crossref], [PubMed], [CAS], Google Scholar
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Nanoscale Chemical Imaging of a Single Catalyst Particle with Tip-Enhanced Fluorescence Microscopy
Kumar, Naresh; Kalirai, Sam; Wain, Andrew J.; Weckhuysen, Bert M.
ChemCatChem (2019), 11 (1), 417-423CODEN: CHEMK3; ISSN:1867-3880. (Wiley-VCH Verlag GmbH & Co. KGaA)
Detg. the active site in real-life solid catalysts remains an intellectual challenge and is crucial for exploring the road towards their rational design. In recent years various micro-spectroscopic methods have revealed valuable structure-activity data at the level of a single catalyst particle, even under reaction conditions.. Herein, we introduce Tip-Enhanced FLuorescence (TEFL) microscopy as a novel and versatile characterization tool for catalysis research. This has been achieved using a Fluid Catalytic Cracking (FCC) catalyst as showcase material. Thin sectioning of industrially used FCC particles together with selective staining of Bronsted acidity has enabled high-resoln. TEFL mapping of different catalyst regions. Hyperspectral information gained via TEFL microscopy reveals a spatial distribution of Bronsted acidity within individual zeolite domains in different regions of the FCC catalyst particle. Comparison of TEFL measurements from different FCC particles showed significant intra- and inter-particle heterogeneities both in zeolite domain size and chem. reactivity.
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Schmid, T.; Yeo, B. S.; Leong, G.; Stadler, J.; Zenobi, R. Performing tip-enhanced Raman spectroscopy in liquids. J. Raman Spectrosc. 2009, 40 (10), 1392– 1399, DOI: 10.1002/jrs.2387
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30
Scherger, J. D.; Foster, M. D. Tunable, liquid resistant tip-enhanced Raman spectroscopy probes: Toward label-free nano-resolved imaging of biological systems. Langmuir 2017, 33 (31), 7818– 7825, DOI: 10.1021/acs.langmuir.7b01338
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Tunable, Liquid Resistant Tip Enhanced Raman Spectroscopy Probes: Toward Label-Free Nano-Resolved Imaging of Biological Systems
Scherger, Jacob D.; Foster, Mark D.
Langmuir (2017), 33 (31), 7818-7825CODEN: LANGD5; ISSN:0743-7463. (American Chemical Society)
Tip enhanced Raman spectroscopy (TERS) has been established as a powerful, noninvasive technique for chem. identification at the nanoscale. However, difficulties, including the degrdn. of probes, limit its use in liq. systems. Here TERS probes for studies in aq. environments have been demonstrated using titanium nitride coatings with an alumina protective layer. The probes show enhancement in signal intensity as high as 380% in liq. measurements, and the probe resonance can be tuned by varying deposition conditions to optimize performance for different laser sources and types of samples. This development of inexpensively produced probes suited for studies in aq. environments enables its wider use for fields such as biol. and biomedicine in which aq. environments are the norm.
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Touzalin, T.; Dauphin, A. L.; Joiret, S.; Lucas, I. T.; Maisonhaute, E. Tip-enhanced Raman spectroscopy imaging of opaque samples in organic liquid. Phys. Chem. Chem. Phys. 2016, 18 (23), 15510– 15513, DOI: 10.1039/C6CP02596J
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32
Zeng, Z.-C.; Huang, S.-C.; Wu, D.-Y.; Meng, L.-Y.; Li, M.-H.; Huang, T.-X.; Zhong, J.-H.; Wang, X.; Yang, Z.-L.; Ren, B. Electrochemical tip-enhanced Raman spectroscopy. J. Am. Chem. Soc. 2015, 137 (37), 11928– 11931, DOI: 10.1021/jacs.5b08143
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32
Electrochemical Tip-Enhanced Raman Spectroscopy
Zeng, Zhi-Cong; Huang, Sheng-Chao; Wu, De-Yin; Meng, Ling-Yan; Li, Mao-Hua; Huang, Teng-Xiang; Zhong, Jin-Hui; Wang, Xiang; Yang, Zhi-Lin; Ren, Bin
Journal of the American Chemical Society (2015), 137 (37), 11928-11931CODEN: JACSAT; ISSN:0002-7863. (American Chemical Society)
Interfacial properties are highly important to the performance of some energy-related systems. The in-depth understanding of the interface requires highly sensitive in situ techniques that can provide fingerprint mol. information at nanometer resoln. The authors developed an electrochem. tip-enhanced Raman spectroscopy (EC-TERS) by introduction of the light horizontally to the EC-STM cell to minimize the optical distortion and to keep the TERS measurement under a well-controlled condition. The authors obtained potential-dependent EC-TERS from the adsorbed arom. mol. on a Au(111) surface and obsd. a substantial change in the mol. configuration with potential as a result of the protonation and deprotonation of the mol. Such a change was not observable in EC-SERS (surface-enhanced), indicating EC-TERS can more faithfully reflect the fine interfacial structure than EC-SERS. This work will open a new era for using EC-TERS as an important nanospectroscopy tool for the mol. level and nanoscale anal. of some important electrochem. systems including solar cells, lithium ion batteries, fuel cells, and corrosion.
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33
Kurouski, D.; Mattei, M.; Van Duyne, R. P. Probing redox reactions at the nanoscale with electrochemical tip-enhanced Raman spectroscopy. Nano Lett. 2015, 15 (12), 7956– 7962, DOI: 10.1021/acs.nanolett.5b04177
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33
Probing Redox Reactions at the Nanoscale with Electrochemical Tip-Enhanced Raman Spectroscopy
Kurouski, Dmitry; Mattei, Michael; Van Duyne, Richard P.
Nano Letters (2015), 15 (12), 7956-7962CODEN: NALEFD; ISSN:1530-6984. (American Chemical Society)
A fundamental understanding of electrochem. processes at the nanoscale is crucial to solving problems in research areas as diverse as electrocatalysis, energy storage, biol. electron transfer, and plasmon-driven chem. However, there is currently no technique capable of directly providing chem. information about mols. undergoing heterogeneous charge transfer at the nanoscale. Tip-enhanced Raman spectroscopy (TERS) uniquely offers subnanometer spatial resoln. and single-mol. sensitivity, making it the ideal tool for studying nanoscale electrochem. processes with high chem. specificity. The authors demonstrate the 1st electrochem. TERS (EC-TERS) study of the nanoscale redox behavior of Nile Blue (NB), and compare these results with conventional cyclic voltammetry (CV). The authors successfully monitor the disappearance of the 591 cm-1 band of NB upon redn. and its reversible reappearance upon oxidn. during the CV. The authors observe a neg. shift of >100 mV in the onset of the potential response of the TERS intensity of the 591 cm-1 band, compared to the onset of faradaic current in the CV. The authors hypothesize that perturbation of the elec. double-layer by the TERS tip locally alters the effective potential experienced by NB mols. in the tip-sample junction. However, the tip has no effect on the local charge transfer kinetics. Addnl., the authors observe step-like behavior in some TERS voltammograms corresponding to redn. and oxidn. of single or few NB mols. Also the coverage of NB is nonuniform across the ITO surface. The authors conclude with a discussion of methods to overcome the perturbation of the double-layer and general considerations for using TERS to study nanoscale electrochem. processes.
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Kumar, N.; Su, W.; Vesely, M.; Weckhuysen, B. M.; Pollard, A. J.; Wain, A. J. Nanoscale chemical imaging of solid-liquid interfaces using tip-enhanced Raman spectroscopy. Nanoscale 2018, 10 (4), 1815– 1824, DOI: 10.1039/C7NR08257F
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34
Nanoscale chemical imaging of solid-liquid interfaces using tip-enhanced Raman spectroscopy
Kumar, Naresh; Su, Weitao; Vesely, Martin; Weckhuysen, Bert M.; Pollard, Andrew J.; Wain, Andrew J.
Nanoscale (2018), 10 (4), 1815-1824CODEN: NANOHL; ISSN:2040-3372. (Royal Society of Chemistry)
Tip-enhanced Raman spectroscopy (TERS) is a powerful tool for non-destructive and label-free surface mol. mapping at the nanoscale. However, to date nanoscale resoln. chem. imaging in a liq. environment has not been possible, in part due to the lack of robust TERS probes that are stable when immersed in a liq. In this work, we have addressed this challenge by developing plasmonically-active TERS probes with a multilayer metal coating structure that can be successfully used within a liq. environment. Using these novel TERS probes, we have compared the plasmonic enhancement of TERS signals in air and water environments for both gap mode and non-gap mode configurations and show that in both cases the plasmonic enhancement decreases in water. To better understand the signal attenuation in water, we have performed numerical simulations that revealed a neg. correlation between the elec. field enhancement at the TERS probe-apex and the refractive index of the surrounding medium. Finally, using these robust probes we demonstrate TERS imaging with nanoscale spatial resoln. in a water environment for the first time by employing single-wall carbon nanotubes as a model sample. Our findings are expected to broaden the scope of TERS to a range of scientific disciplines in which nanostructured solid-liq. interfaces play a key role.
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35
Su, W.; Kumar, N.; Mignuzzi, S.; Crain, J.; Roy, D. Nanoscale mapping of excitonic processes in single-layer MoS 2 using tip-enhanced photoluminescence microscopy. Nanoscale 2016, 8 (20), 10564– 10569, DOI: 10.1039/C5NR07378B
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35
Nanoscale mapping of excitonic processes in single-layer MoS2 using tip-enhanced photoluminescence microscopy
Su, Weitao; Kumar, Naresh; Mignuzzi, Sandro; Crain, Jason; Roy, Debdulal
Nanoscale (2016), 8 (20), 10564-10569CODEN: NANOHL; ISSN:2040-3372. (Royal Society of Chemistry)
In two-dimensional (2D) semiconductors, photoluminescence originating from recombination processes involving neutral electron-hole pairs (excitons) and charged complexes (trions) is strongly affected by the localized charge transfer due to inhomogeneous interactions with the local environment and surface defects. Herein, we demonstrate the first nanoscale mapping of excitons and trions in single-layer MoS2 using the full spectral information obtained via tip-enhanced photoluminescence (TEPL) microscopy along with tip-enhanced Raman spectroscopy (TERS) imaging of a 2D flake. Finally, we show the mapping of the PL quenching center in single-layer MoS2 with an unprecedented spatial resoln. of 20 nm. In addn., our research shows that unlike in aperture-scanning near field microscopy, preferential exciton emission mapping at the nanoscale using TEPL and Raman mapping using TERS can be obtained simultaneously using this method that can be used to correlate the structural and excitonic properties.
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36
Kumar, N.; Spencer, S. J.; Imbraguglio, D.; Rossi, A. M.; Wain, A. J.; Weckhuysen, B. M.; Roy, D. Extending the plasmonic lifetime of tip-enhanced Raman spectroscopy probes. Phys. Chem. Chem. Phys. 2016, 18 (19), 13710– 13716, DOI: 10.1039/C6CP01641C
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36
Extending the plasmonic lifetime of tip-enhanced Raman spectroscopy probes
Kumar, Naresh; Spencer, Steve J.; Imbraguglio, Dario; Rossi, Andrea M.; Wain, Andrew J.; Weckhuysen, Bert M.; Roy, Debdulal
Physical Chemistry Chemical Physics (2016), 18 (19), 13710-13716CODEN: PPCPFQ; ISSN:1463-9076. (Royal Society of Chemistry)
Tip-enhanced Raman spectroscopy (TERS) is an emerging technique for simultaneous mapping of chem. compn. and topog. of a surface at the nanoscale. However, rapid degrdn. of TERS probes, esp. those coated with silver, is a major bottleneck to the widespread uptake of this technique and severely prohibits the success of many TERS expts. In this work, we carry out a systematic time-series study of the plasmonic degrdn. of Ag-coated TERS probes under different environmental conditions and demonstrate that a low oxygen (<1 ppm) and a low moisture (<1 ppm) environment can significantly improve the plasmonic lifetime of TERS probes from a few hours to a few months. Furthermore, using XPS measurements on Ag nanoparticles we show that the rapid plasmonic degrdn. of Ag-coated TERS probes can be correlated to surface oxide formation. Finally, we present practical guidelines for the effective use and storage of TERS probes to improve their plasmonic lifetime based on the results of this study.
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Kalbacova, J.; Rodriguez, R. D.; Desale, V.; Schneider, M.; Amin, I.; Jordan, R.; Zahn, D. R. Chemical stability of plasmon-active silver tips for tip-enhanced Raman spectroscopy. Nanospectroscopy 2015, 1, 12– 18, DOI: 10.2478/nansp-2014-0002
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38
Opilik, L.; Dogan, Ü.; Szczerbiński, J.; Zenobi, R. Degradation of silver near-field optical probes and its electrochemical reversal. Appl. Phys. Lett. 2015, 107 (9), 091109, DOI: 10.1063/1.4929880
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38
Degradation of silver near-field optical probes and its electrochemical reversal
Opilik, Lothar; Dogan, Uzeyir; Szczerbinski, Jacek; Zenobi, Renato
Applied Physics Letters (2015), 107 (9), 091109/1-091109/5CODEN: APPLAB; ISSN:0003-6951. (American Institute of Physics)
Deterioration of the outstanding optical properties of elemental silver due to atm. corrosion compromises its use in the field of plasmonics. Therefore, more chem. inert, but more lossy, metals (e.g., gold) are often used as a compromise. Silver tips for near-field optical microscopy are only utilized by specialized labs. with inhouse tip prodn. facilities. This article presents a time-dependent study of the effect of atm. corrosion on the electromagnetic enhancement of solid silver tips. It was found that chem. degrdn. renders them unusable for tip-enhanced Raman spectroscopy (TERS) within the first two days after prodn. Furthermore, we present a simple electrochem. method for recovering the enhancing effect of corroded silver tips, as well as for storing freshly prepd. probes, for example, for easy shipment. The present work greatly simplifies the exptl. aspects of near-field optical microscopy, which should make near-field optical techniques, and, in particular, TERS, more accessible to the scientific community. (c) 2015 American Institute of Physics.
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Yeo, B. S.; Stadler, J.; Schmid, T.; Zenobi, R.; Zhang, W. H. Tip-enhanced Raman spectroscopy - Its status, challenges and future directions. Chem. Phys. Lett. 2009, 472 (1–3), 1– 13, DOI: 10.1016/j.cplett.2009.02.023
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39
Tip-enhanced Raman Spectroscopy - Its status, challenges and future directions
Yeo, Boon-Siang; Stadler, Johannes; Schmid, Thomas; Zenobi, Renato; Zhang, Weihua
Chemical Physics Letters (2009), 472 (1-3), 1-13CODEN: CHPLBC; ISSN:0009-2614. (Elsevier B.V.)
A review. Tip-enhanced Raman Spectroscopy (TERS) showed promise as a tool for in situ nanoscale chem. anal., and is also leading to a better understanding of the fundamentals of surface-enhanced Raman Spectroscopy. The latest developments, challenges and applications of TERS are discussed. The focus is on tip plasmonics, single mol. detection and nanoscale chem. anal. of biol. samples.
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40
Barrios, C. A.; Malkovskiy, A. V.; Kisliuk, A. M.; Sokolov, A. P.; Foster, M. D. Highly stable, protected plasmonic nanostructures for tip-enhanced Raman spectroscopy. J. Phys. Chem. C 2009, 113 (19), 8158– 8161, DOI: 10.1021/jp8098126
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41
Opilik, L.; Dogan, U. z.; Li, C.-Y.; Stephanidis, B.; Li, J.-F.; Zenobi, R. Chemical production of thin protective coatings on optical nanotips for tip-enhanced Raman spectroscopy. J. Phys. Chem. C 2016, 120 (37), 20828– 20832, DOI: 10.1021/acs.jpcc.6b02147
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41
Chemical Production of Thin Protective Coatings on Optical Nanotips for Tip-Enhanced Raman Spectroscopy
Opilik, Lothar; Dogan, Uzeyir; Li, Chao-Yu; Stephanidis, Bruno; Li, Jian-Feng; Zenobi, Renato
Journal of Physical Chemistry C (2016), 120 (37), 20828-20832CODEN: JPCCCK; ISSN:1932-7447. (American Chemical Society)
Tip-enhanced Raman spectroscopy (TERS) provides topog. and chem. information simultaneously with a spatial resoln. well below the optical diffraction limit; however, the typically used noble-metal nanotips are prone to unwanted chemisorption, and when silver is used, the enhancement quickly fades due to chem. degrdn. during storage and use. In the present work, we demonstrate a method to produce strongly enhancing tips for TERS, which are protected against undesired chemisorption and (in the case of silver) have a significantly longer lifetime than unprotected tips. This was achieved by chem. coating of an ultrathin (few nanometers) and pinhole-free silica shell on top of the enhancing noble-metal nanostructures. The enhancement achieved with the protected silver tips was comparable with the typical tip enhancement for TERS; i.e., no major constraints for TERS expts. resulted from the protective coatings. These shell-isolated tips could widen the scope of tip-enhanced Raman spectroscopy by potentially allowing for in situ studies of, for example, surface catalysis and biol. systems.
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42
Pourbaix, M. Atlas of Electrochemical Equilibria in Aqueous Solutions; National Association of Corrosion Engineers: Houston, TX, 1974.
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There is no corresponding record for this reference.
43
Huang, Y.-P. Shell-isolated tip-enhanced Raman and fluorescence spectroscopy. Angew. Chem., Int. Ed. 2018, 57 (25), 7523– 7527, DOI: 10.1002/anie.201802892
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43
Shell-Isolated Tip-Enhanced Raman and Fluorescence Spectroscopy
Huang, Ya-Ping; Huang, Sheng-Chao; Wang, Xiang-Jie; Bodappa, Nataraju; Li, Chao-Yu; Yin, Hao; Su, Hai-Sheng; Meng, Meng; Zhang, Hua; Ren, Bin; Yang, Zhi-Lin; Zenobi, Renato; Tian, Zhong-Qun; Li, Jian-Feng
Angewandte Chemie, International Edition (2018), 57 (25), 7523-7527CODEN: ACIEF5; ISSN:1433-7851. (Wiley-VCH Verlag GmbH & Co. KGaA)
Tip-enhanced Raman spectroscopy can provide mol. fingerprint information with ultrahigh spatial resoln., but the tip will be easily contaminated, thus leading to artifacts. It also remains a great challenge to establish tip-enhanced fluorescence because of the quenching resulting from the proximity of the metal tip. Herein, we report shell-isolated tip-enhanced Raman and fluorescence spectroscopies by employing ultrathin shell-isolated tips fabricated by at. layer deposition. Such shell-isolated tips not only show outstanding electromagnetic field enhancement in TERS but also exclude interference by contaminants, thus greatly promoting applications in soln. Tip-enhanced fluorescence has also been achieved using these shell-isolated tips, with enhancement factors of up to 1.7×103, consistent with theor. simulations. Furthermore, tip-enhanced Raman and fluorescence signals are acquired simultaneously, and their relative intensities can be manipulated by changing the shell thickness. This work opens a new avenue for ultrahigh resoln. surface anal. using plasmon-enhanced spectroscopies.
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44
Vaidya, P. D.; Lopez-Sanchez, J. A. Review of hydrogen production by catalytic aqueous-phase reforming. ChemistrySelect 2017, 2 (22), 6563– 6576, DOI: 10.1002/slct.201700905
[Crossref], Google Scholar
There is no corresponding record for this reference.
45
Navarro, R. M.; Pena, M.; Fierro, J. Hydrogen production reactions from carbon feedstocks: fossil fuels and biomass. Chem. Rev. 2007, 107 (10), 3952– 3991, DOI: 10.1021/cr0501994
[ACS Full Text ], [CAS], Google Scholar
45
Hydrogen Production Reactions from Carbon Feedstocks: Fossil Fuels and Biomass
Navarro, R. M.; Pena, M. A.; Fierro, J. L. G.
Chemical Reviews (Washington, DC, United States) (2007), 107 (10), 3952-3991CODEN: CHREAY; ISSN:0009-2665. (American Chemical Society)
A review. The fuel cell technol., as well as the prodn. of ammonia and other traditional used, required large amts. of H2. Feedstocks for H2 are methane, liq. hydrocarbons, methanol, coal, biomass and biomass derived products. The common processes to produce H2 from these feeds are steam reforming, partial and autothermal oxidn., catalytic decompn. of CH4, CH4 aromatization, and gasification of biomass in supercrit. water.
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Huang, Y.-F.; Zhu, H.-P.; Liu, G.-K.; Wu, D.-Y.; Ren, B.; Tian, Z.-Q. When the signal is not from the original molecule to be detected: chemical transformation of para-aminothiophenol on Ag during the SERS measurement. J. Am. Chem. Soc. 2010, 132 (27), 9244– 9246, DOI: 10.1021/ja101107z
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46
When the signal is not from the original molecule to be detected: chemical transformation of para-aminothiophenol on Ag during the SERS measurement
Huang, Yi-Fan; Zhu, Hong-Ping; Liu, Guo-Kun; Wu, De-Yin; Ren, Bin; Tian, Zhong-Qun
Journal of the American Chemical Society (2010), 132 (27), 9244-9246CODEN: JACSAT; ISSN:0002-7863. (American Chemical Society)
Surface-enhanced Raman spectroscopy (SERS) has long been considered as a noninvasive technique that can obtain the fingerprint vibrational information of surface species. We demonstrated in this paper that a laser with a power level considered to be low in the traditional SERS measurement can already lead to a significant surface reaction. para-Aminothiophenol, an important probe mol. in SERS, was found to be oxidized to form 4,4'-dimercaptoazobenzene (DMAB) on a roughened silver surface during the SERS measurement. The assumption was confirmed exptl. by surface mass spectroscopy and SERS as well as electrochem. of the synthesized DMAB, which agrees well with theor. calcns. A defocusing method was used to avoid the laser induced surface reaction and perform reliable SERS characterization and identification, which can effectively avoid erroneous interpretation of the distorted exptl. result.
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47
Mehtani, D.; Lee, N.; Hartschuh, R.; Kisliuk, A.; Foster, M.; Sokolov, A.; Čajko, F.; Tsukerman, I. Optical properties and enhancement factors of the tips for apertureless near-field optics. J. Opt. A: Pure Appl. Opt. 2006, 8 (4), S183– S190, DOI: 10.1088/1464-4258/8/4/S19
[Crossref], Google Scholar
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48
Agapov, R. L.; Malkovskiy, A. V.; Sokolov, A. P.; Foster, M. D. Prolonged blinking with TERS probes. J. Phys. Chem. C 2011, 115 (18), 8900– 8905, DOI: 10.1021/jp111762u
[ACS Full Text ], Google Scholar
There is no corresponding record for this reference.
49
Kumar, N.; Rae, A.; Roy, D. Accurate measurement of enhancement factor in tip-enhanced Raman spectroscopy through elimination of far-field artefacts. Appl. Phys. Lett. 2014, 104 (12), 123106, DOI: 10.1063/1.4869184
[Crossref], Google Scholar
There is no corresponding record for this reference.
50
Zhang, Z.; Merk, V.; Hermanns, A.; Unger, W. E. S.; Kneipp, J. Role of metal cations in plasmon-catalyzed oxidation: A case study of p-aminothiophenol dimerization. ACS Catal. 2017, 7 (11), 7803– 7809, DOI: 10.1021/acscatal.7b02700
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50
Role of Metal Cations in Plasmon-Catalyzed Oxidation: A Case Study of p-Aminothiophenol Dimerization
Zhang, Zhiyang; Merk, Virginia; Hermanns, Anja; Unger, Wolfgang E. S.; Kneipp, Janina
ACS Catalysis (2017), 7 (11), 7803-7809CODEN: ACCACS; ISSN:2155-5435. (American Chemical Society)
The mechanism of the plasmon-catalyzed reaction of p-aminothiophenol (PATP) to 4,4'-dimercaptoazobenzene (DMAB) on the surface of metal nanoparticles has been discussed using data from surface-enhanced Raman scattering of DMAB. Oxides and hydroxides formed in a plasmon-catalyzed process were proposed to play a central role in the reaction. Here, we report DMAB formation on gold nanoparticles occurring in the presence of the metal cations Ag+, Au3+, Pt4+, and Hg2+. The expts. were carried out under conditions where formation of gold oxide or hydroxide from the nanoparticles can be excluded and at high pH where the formation of the corresponding oxidic species from the metal ions is favored. On the basis of our results, we conclude that, under these conditions, the selective oxidn. of PATP to DMAB takes place via formation of a metal oxide from the ionic species in a plasmon-catalyzed process. By evidencing the necessity of the presence of the metal cations, the reported results underpin the importance of metal oxides in the reaction.
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51
Zhao, L. B.; Zhang, M.; Huang, Y. F.; Williams, C. T.; Wu, D. Y.; Ren, B.; Tian, Z. Q. Theoretical study of plasmon-enhanced surface catalytic coupling reactions of aromatic amines and nitro compounds. J. Phys. Chem. Lett. 2014, 5 (7), 1259– 1266, DOI: 10.1021/jz5003346
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51
Theoretical Study of Plasmon-Enhanced Surface Catalytic Coupling Reactions of Aromatic Amines and Nitro Compounds
Zhao, Liu-Bin; Zhang, Meng; Huang, Yi-Fan; Williams, Christopher T.; Wu, De-Yin; Ren, Bin; Tian, Zhong-Qun
Journal of Physical Chemistry Letters (2014), 5 (7), 1259-1266CODEN: JPCLCD; ISSN:1948-7185. (American Chemical Society)
Taking advantage of the unique capacity of surface plasmon resonance, plasmon-enhanced heterogeneous catalysis has recently come into focus as a promising technique for high performance light-energy conversion. This work performs a theor. study on the reaction mechanism for conversions of p-aminothiophenol (PATP) and p-nitrothiophenol (PNTP) to arom. azo species, p,p'-dimercaptoazobenzene (DMAB). In the absence of O2 or H2, the plasmon-driven photocatalysis mechanism (hot electron-hole reactions) is the major reaction channel. In the presence of O2 or H2, the plasmon-assisted surface catalysis mechanism (activated oxygen/hydrogen reactions) is the major reaction channel. The present results show that the coupling reactions of PATP and PNTP strongly depend on the soln. pH, the irradn. wavelength, the irradn. power, and the nature of metal substrates as well as the surrounding atm. The present study has drawn a fundamental phys. picture for understanding plasmon-enhanced heterogeneous catalysis.
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52
Mock, J. J.; Smith, D. R.; Schultz, S. Local refractive index dependence of plasmon resonance spectra from individual nanoparticles. Nano Lett. 2003, 3 (4), 485– 491, DOI: 10.1021/nl0340475
[ACS Full Text ], [CAS], Google Scholar
52
Local Refractive Index Dependence of Plasmon Resonance Spectra from Individual Nanoparticles
Mock, Jack J.; Smith, David R.; Schultz, Sheldon
Nano Letters (2003), 3 (4), 485-491CODEN: NALEFD; ISSN:1530-6984. (American Chemical Society)
The authors present an exptl. optical darkfield microscope study of the dependence of the plasmon resonance spectrum of individual Ag nanoparticles on the local index of refraction. The authors systematically characterize the position of the resonance peaks assocd. with the same set of individual Ag nanoparticles embedded sequentially in index oils with increasing refractive index. This technique effectively allows the local refractive index to be stepped in increments of 0.04. As the local index is increased, the spectrum from each of the nanoparticles generally undergoes a very regular and reproducible red shift; however, the amt. of red shift per index increase varies depending on the shape of the nanoparticle and the mode of excitation. In particular, the spectral peak that occurs in triangular nanoparticles exhibits a noticeably larger red shift than that assocd. with the dipole mode corresponding to spherical nanoparticles. The authors' results are consistent with expts. performed on ensembles of similar nanoparticles and suggest that individual nanoparticles may be used in biosensing applications where currently ensembles are being studied.
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53
Xu, P.; Kang, L.; Mack, N. H.; Schanze, K. S.; Han, X.; Wang, H.-L. Mechanistic understanding of surface plasmon assisted catalysis on a single particle: cyclic redox of 4-aminothiophenol. Sci. Rep. 2013, 3, 2997, DOI: 10.1038/srep02997
[Crossref], [PubMed], [CAS], Google Scholar
53
Mechanistic understanding of surface plasmon assisted catalysis on a single particle: cyclic redox of 4-aminothiophenol
Xu Ping; Kang Leilei; Mack Nathan H; Schanze Kirk S; Han Xijiang; Wang Hsing-Lin
Scientific reports (2013), 3 (), 2997 ISSN:.
Surface plasmon assisted catalysis (SPAC) reactions of 4-aminothiophenol (4ATP) to and back from 4,4'-dimercaptoazobenzene (DMAB) have been investigated by single particle surface enhanced Raman spectroscopy, using a self-designed gas flow cell to control the reductive/oxidative environment over the reactions. Conversion of 4ATP into DMAB is induced by energy transfer (plasmonic heating) from surface plasmon resonance to 4ATP, where O2 (as an electron acceptor) is essential and H2O (as a base) can accelerate the reaction. In contrast, hot electron (from surface plasmon decay) induction drives the reverse reaction of DMAB to 4ATP, where H2O (or H2) acts as the hydrogen source. More interestingly, the cyclic redox between 4ATP and DMAB by SPAC approach has been demonstrated. This SPAC methodology presents a unique platform for studying chemical reactions that are not possible under standard synthetic conditions.
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54
Sun, M.; Xu, H. A novel application of plasmonics: Plasmon-driven surface-catalyzed reactions. Small 2012, 8 (18), 2777– 2786, DOI: 10.1002/smll.201200572
[Crossref], [PubMed], [CAS], Google Scholar
54
A Novel Application of Plasmonics: Plasmon-Driven Surface-Catalyzed Reactions
Sun, Mengtao; Xu, Hongxing
Small (2012), 8 (18), 2777-2786CODEN: SMALBC; ISSN:1613-6810. (Wiley-VCH Verlag GmbH & Co. KGaA)
A review. The first exptl. and theor. evidence of the surface-catalyzed reaction of p,p'-dimercaptoazobenzene (DMAB) produced from para-aminothiophenol (PATP) by local surface plasmons was reported in 2010, and since that time a series of investigations have supported these findings using different exptl. and theor. methods. Recent work has also found that local plasmons can drive a surface-catalyzed reaction of DMAB converted from 4-nitrobenzenethiol (4NBT), assisted by local surface plasmons. There are at least three important discoveries in these investigations: (1) in the field of surface-enhanced Raman scattering (SERS) the widely accepted misinterpretation (since 1994) that the chem. mechanism resulting in three addnl. Raman peaks of PATP in Ag or Au solns. has been cor. with a new mechanism; (2) it is confirmed that SERS is not always a noninvasive technique, and under certain conditions cannot always obtain the vibrational fingerprint information of the original surface species; (3) a novel method to synthesize new mols., induced by local surface plasmons or plasmon waveguides on the nanoscale, has been found. This Review considers recent novel applications of plasmonics to chem. reactions, esp. to plasmon-driven surface-catalyzed reactions.
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55
Kang, L.; Xu, P.; Zhang, B.; Tsai, H.; Han, X.; Wang, H.-L. Laser wavelength- and power-dependent plasmon-driven chemical reactions monitored using single particle surface enhanced Raman spectroscopy. Chem. Commun. 2013, 49 (33), 3389– 3391, DOI: 10.1039/c3cc40732b
[Crossref], [PubMed], [CAS], Google Scholar
55
Laser wavelength- and power-dependent plasmon-driven chemical reactions monitored using single particle surface enhanced Raman spectroscopy
Kang, Leilei; Xu, Ping; Zhang, Bin; Tsai, Hsinhan; Han, Xijiang; Wang, Hsing-Lin
Chemical Communications (Cambridge, United Kingdom) (2013), 49 (33), 3389-3391CODEN: CHCOFS; ISSN:1359-7345. (Royal Society of Chemistry)
Plasmon-driven chem. reaction of p-nitrothiophenol (pNTP) dimerizing into p,p'-dimercaptoazobenzene (DMAB) has been monitored using single particle surface enhanced Raman spectroscopy, which provides laser wavelength- and power-dependent conversion rates of the reaction.
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56
Dai, Z. G.; Xiao, X. H.; Zhang, Y. P.; Ren, F.; Wu, W.; Zhang, S. F.; Zhou, J.; Mei, F.; Jiang, C. Z. In situ Raman scattering study on a controllable plasmon-driven surface catalysis reaction on Ag nanoparticle arrays. Nanotechnology 2012, 23 (33), 335701, DOI: 10.1088/0957-4484/23/33/335701
[Crossref], [PubMed], [CAS], Google Scholar
56
In situ Raman scattering study on a controllable plasmon-driven surface catalysis reaction on Ag nanoparticle arrays
Dai, Z. G.; Xiao, X. H.; Zhang, Y. P.; Ren, F.; Wu, W.; Zhang, S. F.; Zhou, J.; Mei, F.; Jiang, C. Z.
Nanotechnology (2012), 23 (33), 335701/1-335701/6CODEN: NNOTER; ISSN:1361-6528. (Institute of Physics Publishing)
Control of the plasmon-driven chem. reaction for the transformation of 4-nitrobenzenethiol to p,p'-dimercaptoazobenzene by Ag nanoparticle arrays was studied. The Ag nanoparticle arrays were fabricated by means of nanosphere lithog. By changing the PS particle size, the localized surface plasmon resonance (LSPR) peaks of the Ag nanoparticle arrays can be tailored from 460 to 560 nm. The controlled reaction process was monitored by in situ surface-enhanced Raman scattering. The reaction can be dramatically influenced by varying the duration of laser exposure, Ag nanoparticle size, laser power and laser excitation wavelength. The max. reaction speed was achieved when the LSPR wavelength of the Ag nanoparticle arrays matched the laser excitation wavelength. The exptl. results reveal that the strong LSPR can effectively drive the transfer of the "hot" electrons that decay from the plasmon to the reactants. The exptl. results were confirmed by theor. calcns.
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57
Walder, R.; Nelson, N.; Schwartz, D. K. Single molecule observations of desorption-mediated diffusion at the solid-liquid interface. Phys. Rev. Lett. 2011, 107 (15), 156102, DOI: 10.1103/PhysRevLett.107.156102
[Crossref], Google Scholar
There is no corresponding record for this reference.
58
Nelson, N.; Walder, R.; Schwartz, D. K. Single molecule dynamics on hydrophobic self-assembled monolayers. Langmuir 2012, 28 (33), 12108– 12113, DOI: 10.1021/la302369v
[ACS Full Text ], [CAS], Google Scholar
58
Single Molecule Dynamics on Hydrophobic Self-Assembled Monolayers
Nelson, Nathaniel; Walder, Robert; Schwartz, Daniel K.
Langmuir (2012), 28 (33), 12108-12113CODEN: LANGD5; ISSN:0743-7463. (American Chemical Society)
The interactions between adsorbate mols. and hydrophobic surfaces are of significant interest due to their importance in a variety of biol. and sepn. processes. However, it is challenging to extrapolate macroscopic ensemble-averaged force measurements to mol.-level phenomena. Using total internal reflection fluorescence microscopy to image individual mols. at hydrophobic solid-aq. interfaces, the authors directly obsd. dynamic behavior assocd. with the interactions between fluorescently labeled dodecanoic acid (the authors' probe mols.) and self-assembled monolayers (SAM) comprising n-alkyltriethoxysilanes with systematically increasing chain length (from n = 4-18). In all cases, the authors obsd. at least two characteristic surface residence times and two diffusive modes, suggesting the presence of multiple distinct adsorbed populations. In general, the mean surface residence time increased and the mobility decreased with increasing SAM chain length, consistent with stronger probe-surface interactions. However, these trends were not primarily due to changes in characteristic residence times or diffusion coeffs. assocd. with the individual populations but rather to a dramatic increase in the fraction assocd. with the long-lived slow-moving population(s) on long-chain SAMs. In particular, on longer (16-18 carbon) alkylsilane monolayers, the probe mol. exhibited far fewer desorption-mediated flights than on short (4-6 carbon) monolayers. Addnl., probes on the longer chain surfaces were much more likely to exhibit extended surface residence times as opposed to short transient surface visits.
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59
Pardo, L.; Boland, T. A quantitative approach to studying structures and orientation at self-assembled monolayer/fluid interfaces. J. Colloid Interface Sci. 2003, 257 (1), 116– 120, DOI: 10.1016/S0021-9797(02)00022-X
[Crossref], Google Scholar
There is no corresponding record for this reference.
60
Bishnoi, S. W.; Rozell, C. J.; Levin, C. S.; Gheith, M. K.; Johnson, B. R.; Johnson, D. H.; Halas, N. J. All-optical nanoscale pH meter. Nano Lett. 2006, 6 (8), 1687– 1692, DOI: 10.1021/nl060865w
[ACS Full Text ], [CAS], Google Scholar
60
All-Optical Nanoscale pH Meter
Bishnoi, Sandra W.; Rozell, Christopher J.; Levin, Carly S.; Gheith, Muhammed K.; Johnson, Bruce R.; Johnson, Don H.; Halas, Naomi J.
Nano Letters (2006), 6 (8), 1687-1692CODEN: NALEFD; ISSN:1530-6984. (American Chemical Society)
An Au nanoshell with a pH-sensitive mol. adsorbate functions as a standalone, all-optical nanoscale pH meter that monitors its local environment through the pH-dependent surface-enhanced Raman scattering (SERS) spectra of the adsorbate mols. Also, also the performance of such a functional nanodevice can be assessed quant. The complex spectral output is reduced to a simple device characteristic by application of a locally linear manifold approxn. algorithm. The av. accuracy of the nano-meter is ±0.10 pH units across its operating range.
>> More from SciFinder ^®
https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD28XmtF2qsLk%253D&md5=92b0ba07a47e453ccafb95917160f01f
61
Benz, F.; Schmidt, M. K.; Dreismann, A.; Chikkaraddy, R.; Zhang, Y.; Demetriadou, A.; Carnegie, C.; Ohadi, H.; de Nijs, B.; Esteban, R.; Aizpurua, J.; Baumberg, J. J. Single-molecule optomechanics in “picocavities. Science 2016, 354 (6313), 726– 729, DOI: 10.1126/science.aah5243
[Crossref], [PubMed], [CAS], Google Scholar
61
Single-molecule optomechanics in "picocavities"
Benz, Felix; Schmidt, Mikolaj K.; Dreismann, Alexander; Chikkaraddy, Rohit; Zhang, Yao; Demetriadou, Angela; Carnegie, Cloudy; Ohadi, Hamid; de Nijs, Bart; Esteban, Ruben; Aizpurua, Javier; Baumberg, Jeremy J.
Science (Washington, DC, United States) (2016), 354 (6313), 726-729CODEN: SCIEAS; ISSN:0036-8075. (American Association for the Advancement of Science)
Trapping light with noble metal nanostructures overcomes the diffraction limit and can confine light to vols. typically ∼30 cubic nanometers. Individual at. features inside the gap of a plasmonic nanoassembly can localize light to vols. well <1 cubic nanometer (picocavities), enabling optical expts. on the at. scale. These at. features are dynamically formed and disassembled by laser irradn. Although unstable at room temp., picocavities can be stabilized at cryogenic temps., allowing single at. cavities to be probed for many minutes. Unlike traditional optomech. resonators, such extreme optical confinement yields a factor of 106 enhancement of optomech. coupling between the picocavity field and vibrations of individual mol. bonds. This work sets the basis for developing nanoscale nonlinear quantum optics on the single-mol. level.
>> More from SciFinder ^®
https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC28XhvVSnsLrP&md5=ccaa8fdd2c2c6561c678884f6a7557ea
62
Dufrêne, Y. F. Using nanotechniques to explore microbial surfaces. Nat. Rev. Microbiol. 2004, 2 (6), 451– 460, DOI: 10.1038/nrmicro905
[Crossref], [PubMed], [CAS], Google Scholar
62
Using nanotechniques to explore microbial surfaces
Dufrene, Yves F.
Nature Reviews Microbiology (2004), 2 (6), 451-460CODEN: NRMACK; ISSN:1740-1526. (Nature Publishing Group)
A review. The current understanding of microbial surfaces owes much to the development of electron microscopy techniques. Yet, a crucial limitation of electron microscopy is that it cannot be used to examine biol. structures directly in aq. solns. In recent years, however, at. force microscopy (AFM) has provided a range of new opportunities for viewing and manipulating microbial surfaces in their native environments. Examples of AFM-based analyses include visualizing conformational changes in single membrane proteins, the real-time observation of cell-surface dynamics, analyzing the unfolding of cell-surface proteins and detecting individual cell-surface receptors. These analyses have contributed to our understanding of the structure-function relationships of cell surfaces and will hopefully allow new applications to be developed for AFM in medicine and biotechnol.
>> More from SciFinder ^®
https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD2cXktVyisr4%253D&md5=c1f0fc9bfe4ea36e1fc4524952d551a8
63
Weaver, M. J.; Gao, X. In situ electrochemical surface science. Annu. Rev. Phys. Chem. 1993, 44 (1), 459– 494, DOI: 10.1146/annurev.pc.44.100193.002331
[Crossref], Google Scholar
There is no corresponding record for this reference.

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Shahar Dery, Suhong Kim, Daniel Feferman, Hillel Mehlman, F. Dean Toste, Elad Gross. Site-dependent selectivity in oxidation reactions on single Pt nanoparticles. Physical Chemistry Chemical Physics 2020, 22 (34) , 18765-18769. https://doi.org/10.1039/D0CP00642D
Jing-Liang Yang, Hong-Jia Wang, Hua Zhang, Zhong-Qun Tian, Jian-Feng Li. Probing Hot Electron Behaviors by Surface-Enhanced Raman Spectroscopy. Cell Reports Physical Science 2020, 1 (9) , 100184. https://doi.org/10.1016/j.xcrp.2020.100184
Leila Negahdar, Christopher M. A. Parlett, Mark A. Isaacs, Andrew M. Beale, Karen Wilson, Adam F. Lee. Shining light on the solid–liquid interface: in situ / operando monitoring of surface catalysis. Catalysis Science & Technology 2020, 10 (16) , 5362-5385. https://doi.org/10.1039/D0CY00555J
Andrew J. Wilson, Dinumol Devasia, Prashant K. Jain. Nanoscale optical imaging in chemistry. Chemical Society Reviews 2020, 49 (16) , 6087-6112. https://doi.org/10.1039/D0CS00338G
Ryo Kato, Koki Taguchi, Ravi Yadav, Takayuki Umakoshi, Prabhat Verma. One-side metal-coated pyramidal cantilever tips for highly reproducible tip-enhanced Raman spectroscopy. Nanotechnology 2020, 31 (33) , 335207. https://doi.org/10.1088/1361-6528/ab90b6
Dmitry Kurouski, Alexandre Dazzi, Renato Zenobi, Andrea Centrone. Infrared and Raman chemical imaging and spectroscopy at the nanoscale. Chemical Society Reviews 2020, 49 (11) , 3315-3347. https://doi.org/10.1039/C8CS00916C
Xiang Wang, Sheng-Chao Huang, Shu Hu, Sen Yan, Bin Ren. Fundamental understanding and applications of plasmon-enhanced Raman spectroscopy. Nature Reviews Physics 2020, 2 (5) , 253-271. https://doi.org/10.1038/s42254-020-0171-y
Hua Zhang, Jie Wei, Xia-Guang Zhang, Yue-Jiao Zhang, Petar M. Radjenovica, De-Yin Wu, Feng Pan, Zhong-Qun Tian, Jian-Feng Li. Plasmon-Induced Interfacial Hot-Electron Transfer Directly Probed by Raman Spectroscopy. Chem 2020, 6 (3) , 689-702. https://doi.org/10.1016/j.chempr.2019.12.015
Caterina S. Wondergem, Thomas P. van Swieten, Robin G. Geitenbeek, Ben H. Erné, Bert M. Weckhuysen. Extending Surface‐Enhanced Raman Spectroscopy to Liquids Using Shell‐Isolated Plasmonic Superstructures. Chemistry – A European Journal 2019, 25 (69) , 15772-15778. https://doi.org/10.1002/chem.201903204
Jonas H. K. Pfisterer, Masoud Baghernejad, Giovanni Giuzio, Katrin F. Domke. Reactivity mapping of nanoscale defect chemistry under electrochemical reaction conditions. Nature Communications 2019, 10 (1) https://doi.org/10.1038/s41467-019-13692-3
Yukun Gao, Nan Yang, Sichen Lu, Tingting You, Penggang Yin. In situ monitoring of plasmon-driven photocatalytic reactions at gas–liquid–solid three-phase interfaces by surface-enhanced Raman spectroscopy. Journal of Materials Chemistry C 2019, 7 (32) , 9926-9932. https://doi.org/10.1039/C9TC02924A

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Figure 1
Figure 1. Schematic of the experimental TERS setup used in this work for spatially resolved mapping of plasmon-assisted oxidation of p-aminothiophenol (pATP) to p,p′-dimercaptoazobenzene (DMAB) over a heterogeneous Ag substrate in an aqueous environment.
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Figure 2
Figure 2. Time series TERS (red) and far-field Raman (blue) spectra measured from a PEDOT:PSS thin film on glass after exposing (a) unprotected TERS probes for 0, 10, and 170 h and (b) ZrO₂-protected TERS probes for 2, 33, and 140 days to the ambient environment. Integration time: 30 s. Laser power: 50 μW. Plots of TERS contrast versus exposure time of representative TERS probes to the ambient environment for measurements presented in (c) Figures 2a and S6 and (d) Figures 2b and S7. In this study, a thin film of PEDOT:PSS was chosen to measure the lifetime of the zirconia-coated TERS tips because of its high chemical stability, low surface roughness, and strong Raman signal. (30,36,40,47,48) For example, the root-mean-square surface roughness of a spin-coated PEDOT:PSS film has been shown to be 1.2 ± 0.1 nm using tapping mode AFM, confirming a smooth topography. (49) In order to further minimize the effect of surface roughness, the time series contrast plotted in Figure 2c,d was measured from an average of three TERS and far-field measurements conducted at different areas on the PEDOT:PSS thin film.
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Figure 3
Figure 3. Maps of pATP → DMAB at the TERS probe apex obtained using the intensity of the 1437 cm^–1 (ν_N═N) DMAB Raman band measured from the pATP SAM on the Ag substrate in (a) air and (b) water. Integration time: 1 s. Laser power: 117 μW. Pixel size: 50 nm. TERS (red) and SERS (blue) spectra measured at the position of maximum DMAB signal in (c) Figure 3a and (d) Figure 3b, with the TERS probe in contact and retracted from the sample, respectively. Integration time: 60 s (Figure 3c) and 1 s (Figure 3d). The asymmetric shape of the reaction areas at the TERS probe apex shown in Figure 3 most likely arises from the combination of the random distribution of Ag grains at the TERS probe apex resulting from the thermal deposition of the Ag layer and the inhomogeneous and asymmetric distribution of the electromagnetic (EM) field intensity in the laser focal spot.
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Figure 4
Figure 4. (a) AFM topography image of a heterogeneous Ag substrate functionalized with pATP. (b) TERS map of the I_DMAB/I₁₀₇₁ intensity ratio for the area marked in (a). Integration time: 1 s. Laser power: 117 μW. Pixel size: 10 nm. (c) Histogram showing the % frequency of the I_DMAB/I₁₀₇₁ ratio in the pATP → DMAB TERS map in (b). (d) TERS spectra from the locations marked as 1–6 in (b) showing different degrees of conversion across the TERS map. Spectra have been normalized to the intensity of the 1071 cm^–1 band for comparison.
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This article references 63 other publications.
1. 1
  Buurmans, I. L. C.; Weckhuysen, B. M. Heterogeneities of individual catalyst particles in space and time as monitored by spectroscopy. Nat. Chem. 2012, 4 (11), 873– 886, DOI: 10.1038/nchem.1478
  [Crossref], [PubMed], [CAS], Google Scholar
  1
  Heterogeneities of individual catalyst particles in space and time as monitored by spectroscopy
  Buurmans, Inge L. C.; Weckhuysen, Bert M.
  Nature Chemistry (2012), 4 (11), 873-886CODEN: NCAHBB; ISSN:1755-4330. (Nature Publishing Group)
  A review. Recent years have witnessed the introduction of spatiotemporal spectroscopy for the characterization of catalysts at work at previously unattainable resoln. and sensitivity. They have revealed that heterogeneous catalysts are more heterogeneous than often expected. Dynamic changes in the nature of active sites, such as their distribution and accessibility, occur both between and within particles. Scientists now have micro- and nanospectroscopic methods at hand to improve the understanding of catalyst heterogeneities and exploit them in catalyst design. Here we review the latest developments within this lively field. The trends include detection of single particles or mols., super-resoln. imaging, the transition from two- to three-dimensional imaging, selective staining, integration of spectroscopy with electron microscopy or scanning probe methods, and measuring under realistic reaction conditions. Such exptl. approaches change the hitherto somewhat static picture of heterogeneous catalysis into one that acknowledges that catalysts behave almost like living objects - explaining why many characterization methods from the life sciences are being incorporated into catalysis research.
  >> More from SciFinder ^®
  https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC38XhsFCgurvI&md5=bb70ab2dcf7b392b8b9a82f7935d105e
2. 2
  Rothenberg, G. Catalysis: Concepts and Green Applications, 2nd ed.; Wiley-VCH: Weinheim, Germany, 2017.
  Google Scholar
  There is no corresponding record for this reference.
3. 3
  Weckhuysen, B. M. In situ Spectroscopy of Catalysts; American Scientific Publishers: Stevenson Ranch, 2004.
  Google Scholar
  There is no corresponding record for this reference.
4. 4
  Mestl, G. In situ Raman spectroscopy - a valuable tool to understand operating catalysts. J. Mol. Catal. A: Chem. 2000, 158 (1), 45– 65, DOI: 10.1016/S1381-1169(00)00042-X
  [Crossref], [CAS], Google Scholar
  4
  In situ Raman spectroscopy - a valuable tool to understand operating catalysts
  Mestl, G.
  Journal of Molecular Catalysis A: Chemical (2000), 158 (1), 45-65CODEN: JMCCF2; ISSN:1381-1169. (Elsevier Science B.V.)
  A review with 49 refs.; laser Raman spectroscopy (LRS) is one of the most powerful tools for the in situ study of catalytic materials and surfaces under working conditions. Raman characterizations can be carried out at temps. as high as 1000 K and in controlled atmospheres. Modern high light-throughput spectrometers permit the recording of the whole spectral range from 100 to 4000 cm-1 at once and time resolns. in the subsecond regime for materials with high Raman cross-sections. Transient temp. or pressure response studies, e.g. pulse expts. with isotope labels, are thus possible, and kinetic and spectroscopic characteristics can be related. Modern quartz fiber optics render possible easy spectroscopic access to catalytic reactors of defined and well characterized operation conditions. Quant. relation of real catalytic steady state operation, e.g. catalytic activity and selectivity, to changes in the catalyst structure is thus made possible. Several in situ LRS studies are discussed including the characterization of supported and unsupported Mo-based catalysts, confocal Raman microspectroscopy of mixed MoVW oxide catalysts, oxygen exchange in Sb2O3/MoO3 oxide phys. mixts. elucidating the catalytic synergy effects, and active surface intermediates during oxidative coupling of methane, and NO and N2O decompn. over Ba/MgO catalysts related to the catalytic reaction via transient pressure step expts.
  >> More from SciFinder ^®
  https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD3cXkvFyltLg%253D&md5=daaf1c17a7183313908fe04dc6527a8b
5. 5
  Verma, P. Tip-enhanced Raman spectroscopy: Technique and recent advances. Chem. Rev. 2017, 117 (9), 6447– 6466, DOI: 10.1021/acs.chemrev.6b00821
  [ACS Full Text ], [CAS], Google Scholar
  5
  Tip-Enhanced Raman Spectroscopy: Technique and Recent Advances
  Verma, Prabhat
  Chemical Reviews (Washington, DC, United States) (2017), 117 (9), 6447-6466CODEN: CHREAY; ISSN:0009-2665. (American Chemical Society)
  A review. This review discusses a relatively new technique for optical nanoimaging at visible wavelength, known as tip-enhanced Raman spectroscopy (TERS). This technique relies on the enhancement and spatial confinement of light in the close vicinity of the apex of a plasmonic nanotip. The plasmonic nanotip can be positioned on the sample and controlled by a suitable scanning probe microscopy, such as at. force microscopy or scanning tunneling microscopy. By raster scanning the nanotip, one can obtain nanoimages with high spatial resoln. While enhancement helps measuring weak phonon modes from a tiny vol. of the sample, confinement delivers extremely high spatial resoln. in nanoimaging. We will discuss the technique of TERS in more detail with several applications and review the recent advances.
  >> More from SciFinder ^®
  https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2sXmslyhu78%253D&md5=0ebe86df82956cfc4b82af6b150541a5
6. 6
  Deckert-Gaudig, T.; Taguchi, A.; Kawata, S.; Deckert, V. Tip-enhanced Raman spectroscopy–from early developments to recent advances. Chem. Soc. Rev. 2017, 46 (13), 4077– 4110, DOI: 10.1039/C7CS00209B
  [Crossref], Google Scholar
  There is no corresponding record for this reference.
7. 7
  Kumar, N.; Drozdz, M. M.; Jiang, H.; Santos, D. M.; Vaux, D. J. Nanoscale mapping of newly-synthesised phospholipid molecules in a biological cell using tip-enhanced Raman spectroscopy. Chem. Commun. 2017, 53 (16), 2451– 2454, DOI: 10.1039/C6CC10226C
  [Crossref], [PubMed], [CAS], Google Scholar
  7
  Nanoscale mapping of newly-synthesised phospholipid molecules in a biological cell using tip-enhanced Raman spectroscopy
  Kumar, Naresh; Drozdz, Marek M.; Jiang, Haibo; Santos, Daniela M.; Vaux, David J.
  Chemical Communications (Cambridge, United Kingdom) (2017), 53 (16), 2451-2454CODEN: CHCOFS; ISSN:1359-7345. (Royal Society of Chemistry)
  Nanoscale chem. mapping of newly-synthesized phospholipid mols. inside a mammalian cell is demonstrated using tip-enhanced Raman spectroscopy (TERS) for the first time using mouse pre-adipocyte cells as a model system. Newly-synthesized membrane phospholipid distribution within a pre-adipocyte cell is mapped with <20 nm spatial resoln., overcoming the diffraction limit of confocal Raman spectroscopy via plasmonic enhancement of Raman signals at a TERS tip-apex.
  >> More from SciFinder ^®
  https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2sXitlOisL4%253D&md5=fc8586ed7c958162bb92c56c072993d8
8. 8
  Yeo, B. S.; Amstad, E.; Schmid, T.; Stadler, J.; Zenobi, R. Nanoscale probing of a polymer-blend thin film with tip-enhanced Raman spectroscopy. Small 2009, 5 (8), 952– 960, DOI: 10.1002/smll.200801101
  [Crossref], [PubMed], [CAS], Google Scholar
  8
  Nanoscale probing of a polymer-blend thin film with tip-enhanced raman spectroscopy
  Yeo, Boon-Siang; Amstad, Esther; Schmid, Thomas; Stadler, Johannes; Zenobi, Renato
  Small (2009), 5 (8), 952-960CODEN: SMALBC; ISSN:1613-6810. (Wiley-VCH Verlag GmbH & Co. KGaA)
  Fundamental advances have been made in the spatially resolved chem. anal. of polymer thin films. Tip-enhanced Raman spectroscopy (TERS) is used to investigate the surface compn. of a mixed polyisoprene (PI) and polystyrene (PS) thin film. High-quality TER spectra are collected from these nonresonant Raman-active polymers. A wealth of structural information is obtained, some of which cannot be acquired with conventional anal. techniques. PI and PS are identified at the surface and subsurface, resp. Differences in the band intensities suggest strongly that the polymer layers are not uniformly thick, and that nanopores are present under the film surface. The continuous PS subsurface layer and subsurface nanopores have hitherto not been identified. These data are obtained with nanometer spatial resoln. Confocal far-field Raman spectroscopy and XPS are employed to corroborate some of the results. With routine prodn. of highly enhancing TERS tips expected in the near future, it is predicted that TERS will be of great use for the rigorous chem. anal. of polymer and other composite systems with nanometer spatial resoln.
  >> More from SciFinder ^®
  https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD1MXlslOksrk%253D&md5=b91acddabddf450c2f6ad66bc1567922
9. 9
  Lucia, A.; Cacioppo, O. A.; Iulianella, E.; Latessa, L.; Moccia, G.; Passeri, D.; Rossi, M. Capability of tip-enhanced Raman spectroscopy about nanoscale analysis of strained silicon for semiconductor devices production. Appl. Phys. Lett. 2017, 110 (10), 103105, DOI: 10.1063/1.4978261
  [Crossref], Google Scholar
  There is no corresponding record for this reference.
10. 10
  Berweger, S.; Neacsu, C. C.; Mao, Y.; Zhou, H.; Wong, S. S.; Raschke, M. B. Optical nanocrystallography with tip-enhanced phonon Raman spectroscopy. Nat. Nanotechnol. 2009, 4 (8), 496– 499, DOI: 10.1038/nnano.2009.190
  [Crossref], [PubMed], [CAS], Google Scholar
  10
  Optical nanocrystallography with tip-enhanced phonon Raman spectroscopy
  Berweger, Samuel; Neacsu, Catalin C.; Mao, Yuanbing; Zhou, Hongjun; Wong, Stanislaus S.; Raschke, Markus B.
  Nature Nanotechnology (2009), 4 (8), 496-499CODEN: NNAABX; ISSN:1748-3387. (Nature Publishing Group)
  Conventional phonon Raman spectroscopy is a powerful exptl. technique for the study of cryst. solids that allows crystallog., phase and domain identification on length scales down to ∼1 μm. Here we demonstrate the extension of tip-enhanced Raman spectroscopy to optical crystallog. on the nanoscale by identifying intrinsic ferroelec. domains of individual BaTiO3 nanocrystals through selective probing of different transverse optical phonon modes in the system. The technique is generally applicable for most crystal classes, and for example, structural inhomogeneities, phase transitions, ferroic order and related finite-size effects occurring on nanometer length scales can be studied with simultaneous symmetry selectivity, nanoscale sensitivity and chem. specificity.
  >> More from SciFinder ^®
  https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD1MXpsFSisbo%253D&md5=7201a2d0a489f69fbe47c3a2a90dd629
11. 11
  Kumar, N.; Zoladek-Lemanczyk, A.; Guilbert, A. A.; Su, W.; Tuladhar, S. M.; Kirchartz, T.; Schroeder, B. C.; McCulloch, I.; Nelson, J.; Roy, D. Simultaneous topographical, electrical and optical microscopy of optoelectronic devices at the nanoscale. Nanoscale 2017, 9 (8), 2723– 2731, DOI: 10.1039/C6NR09057E
  [Crossref], [PubMed], [CAS], Google Scholar
  11
  Simultaneous topographical, electrical and optical microscopy of optoelectronic devices at the nanoscale
  Kumar, Naresh; Zoladek-Lemanczyk, Alina; Guilbert, Anne A. Y.; Su, Weitao; Tuladhar, Sachetan M.; Kirchartz, Thomas; Schroeder, Bob C.; McCulloch, Iain; Nelson, Jenny; Roy, Debdulal; Castro, Fernando A.
  Nanoscale (2017), 9 (8), 2723-2731CODEN: NANOHL; ISSN:2040-3372. (Royal Society of Chemistry)
  Novel optoelectronic devices rely on complex nanomaterial systems where the nanoscale morphol. and local chem. compn. are crit. to performance. However, the lack of anal. techniques that can directly probe these structure-property relationships at the nanoscale presents a major obstacle to device development. In this work, we present a novel method for non-destructive, simultaneous mapping of the morphol., chem. compn. and photoelec. properties with <20 nm spatial resoln. by combining plasmonic optical signal enhancement with elec.-mode scanning probe microscopy. We demonstrate that this combined approach offers subsurface sensitivity that can be exploited to provide mol. information with a nanoscale resoln. in all three spatial dimensions. By applying the technique to an org. solar cell device, we show that the inferred surface and subsurface compn. distribution correlates strongly with the local photocurrent generation and explains macroscopic device performance. For instance, the direct measurement of fullerene phase purity can distinguish between high purity aggregates that lead to poor performance and lower purity aggregates (fullerene intercalated with polymer) that result in strong photocurrent generation and collection. We show that the reliable detn. of the structure-property relationship at the nanoscale can remove ambiguity from macroscopic device data and support the identification of the best routes for device optimization. The multi-parameter measurement approach demonstrated herein is expected to play a significant role in guiding the rational design of nanomaterial-based optoelectronic devices, by opening a new realm of possibilities for advanced investigation via the combination of nanoscale optical spectroscopy with a whole range of scanning probe microscopy modes.
  >> More from SciFinder ^®
  https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2sXotlyqsg%253D%253D&md5=0d7d50c66e4c34695f86fb8fcb002f0e
12. 12
  Yano, T.-a.; Ichimura, T.; Kuwahara, S.; H’Dhili, F.; Uetsuki, K.; Okuno, Y.; Verma, P.; Kawata, S. Tip-enhanced nano-Raman analytical imaging of locally induced strain distribution in carbon nanotubes. Nat. Commun. 2013, 4, 2592, DOI: 10.1038/ncomms3592
  [Crossref], [PubMed], [CAS], Google Scholar
  12
  Tip-enhanced nano-Raman analytical imaging of locally induced strain distribution in carbon nanotubes
  Yano Taka-Aki; Ichimura Taro; Kuwahara Shota; H'dhili Fekhra; Uetsuki Kazumasa; Okuno Yoshito; Verma Prabhat; Kawata Satoshi
  Nature communications (2013), 4 (), 2592 ISSN:.
  Tip-enhanced Raman scattering microscopy is a powerful technique for analysing nanomaterials at high spatial resolution far beyond the diffraction limit of light. However, imaging of intrinsic properties of materials such as individual molecules or local structures has not yet been achieved even with a tip-enhanced Raman scattering microscope. Here we demonstrate colour-coded tip-enhanced Raman scattering imaging of strain distribution along the length of a carbon nanotube. The strain is induced by dragging the nanotube with an atomic force microscope tip. A silver-coated nanotip is employed to enhance and detect Raman scattering from specific locations of the nanotube directly under the tip apex, representing deformation of its molecular alignment because of the existence of local strain. Our technique remarkably provides an insight into localized variations of structural properties in nanomaterials, which could prove useful for a variety of applications of carbon nanotubes and other nanomaterials as functional devices and materials.
  >> More from SciFinder ^®
  https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A280%3ADC%252BC2c%252FmtFegtQ%253D%253D&md5=2c22164629cd9be249728b259cbf61bb
13. 13
  Su, W.; Kumar, N.; Dai, N.; Roy, D. Nanoscale mapping of intrinsic defects in single-layer graphene using tip-enhanced Raman spectroscopy. Chem. Commun. 2016, 52 (53), 8227– 8230, DOI: 10.1039/C6CC01990K
  [Crossref], [PubMed], [CAS], Google Scholar
  13
  Nanoscale mapping of intrinsic defects in single-layer graphene using tip-enhanced Raman spectroscopy
  Su, Weitao; Kumar, Naresh; Dai, Ning; Roy, Debdulal
  Chemical Communications (Cambridge, United Kingdom) (2016), 52 (53), 8227-8230CODEN: CHCOFS; ISSN:1359-7345. (Royal Society of Chemistry)
  Non-gap mode tip-enhanced Raman spectroscopy (TERS) is used for the first time to successfully map the intrinsic defects in single-layer graphene with 20 nm spatial resoln. The nanoscale Raman mapping is enabled by an unprecedented near-field to far-field signal contrast of 8.5 at the Ag-coated TERS tip-apex. These results demonstrate the potential of TERS for characterization of defects in single-layer graphene-based devices at the nanometer length-scale.
  >> More from SciFinder ^®
  https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC28Xps1ShtLY%253D&md5=b2598e27121504da03975c587ba4cd90
14. 14
  Su, W.; Kumar, N.; Mignuzzi, S.; Crain, J.; Roy, D. Nanoscale mapping of excitonic processes in single-layer MoS2 using tip-enhanced photoluminescence microscopy. Nanoscale 2016, 8 (20), 10564– 10569, DOI: 10.1039/C5NR07378B
  [Crossref], [PubMed], [CAS], Google Scholar
  14
  Nanoscale mapping of excitonic processes in single-layer MoS2 using tip-enhanced photoluminescence microscopy
  Su, Weitao; Kumar, Naresh; Mignuzzi, Sandro; Crain, Jason; Roy, Debdulal
  Nanoscale (2016), 8 (20), 10564-10569CODEN: NANOHL; ISSN:2040-3372. (Royal Society of Chemistry)
  In two-dimensional (2D) semiconductors, photoluminescence originating from recombination processes involving neutral electron-hole pairs (excitons) and charged complexes (trions) is strongly affected by the localized charge transfer due to inhomogeneous interactions with the local environment and surface defects. Herein, we demonstrate the first nanoscale mapping of excitons and trions in single-layer MoS2 using the full spectral information obtained via tip-enhanced photoluminescence (TEPL) microscopy along with tip-enhanced Raman spectroscopy (TERS) imaging of a 2D flake. Finally, we show the mapping of the PL quenching center in single-layer MoS2 with an unprecedented spatial resoln. of 20 nm. In addn., our research shows that unlike in aperture-scanning near field microscopy, preferential exciton emission mapping at the nanoscale using TEPL and Raman mapping using TERS can be obtained simultaneously using this method that can be used to correlate the structural and excitonic properties.
  >> More from SciFinder ^®
  https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC28Xms1Witb8%253D&md5=09eab1cfc26cd4243608521994785b99
15. 15
  Su, W.; Kumar, N.; Krayev, A.; Chaigneau, M. In situ topographical chemical and electrical imaging of carboxyl graphene oxide at the nanoscale. Nat. Commun. 2018, 9 (1), 2891, DOI: 10.1038/s41467-018-05307-0
  [Crossref], [PubMed], [CAS], Google Scholar
  15
  In situ topographical chemical and electrical imaging of carboxyl graphene oxide at the nanoscale
  Su Weitao; Su Weitao; Kumar Naresh; Kumar Naresh; Krayev Andrey; Chaigneau Marc
  Nature communications (2018), 9 (1), 2891 ISSN:.
  Visualising the distribution of structural defects and functional groups present on the surface of two-dimensional (2D) materials such as graphene oxide challenges the sensitivity and spatial resolution of the most advanced analytical techniques. Here we demonstrate mapping of functional groups on a carboxyl-modified graphene oxide (GO-COOH) surface with a spatial resolution of ≈10 nm using tip-enhanced Raman spectroscopy (TERS). Furthermore, we extend the capability of TERS by measuring local electronic properties in situ, in addition to the surface topography and chemical composition. Our results reveal that the Fermi level at the GO-COOH surface decreases as the ID/IG ratio increases, correlating the local defect density with the Fermi level at nanometre length-scales. The in situ multi-parameter microscopy demonstrated in this work significantly improves the accuracy of nanoscale surface characterisation, eliminates measurement artefacts, and opens up the possibilities for characterising optoelectronic devices based on 2D materials under operational conditions.
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  https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A280%3ADC%252BB3c7htF2ntg%253D%253D&md5=92962053364bc3a94aae76c162396a52
16. 16
  Kumar, N.; Su, W.; Castro, F. A.; Weckhuysen, B. M. Tip-enhanced Raman spectroscopy applications: From graphene to heterogeneous catalysis. Proc. SPIE Nanoscience & Engineering VI 2018, 10726, 1072608, DOI: 10.1117/12.2322188
  [Crossref], Google Scholar
  There is no corresponding record for this reference.
17. 17
  Zhang, R.; Zhang, Y.; Dong, Z. C.; Jiang, S.; Zhang, C.; Chen, L. G.; Zhang, L.; Liao, Y.; Aizpurua, J.; Luo, Y.; Yang, J. L.; Hou, J. G. Chemical mapping of a single molecule by plasmon-enhanced Raman scattering. Nature 2013, 498 (7452), 82– 86, DOI: 10.1038/nature12151
  [Crossref], [PubMed], [CAS], Google Scholar
  17
  Chemical mapping of a single molecule by plasmon-enhanced Raman scattering
  Zhang, R.; Zhang, Y.; Dong, Z. C.; Jiang, S.; Zhang, C.; Chen, L. G.; Zhang, L.; Liao, Y.; Aizpurua, J.; Luo, Y.; Yang, J. L.; Hou, J. G.
  Nature (London, United Kingdom) (2013), 498 (7452), 82-86CODEN: NATUAS; ISSN:0028-0836. (Nature Publishing Group)
  Visualizing individual mols. with chem. recognition is a longstanding target in catalysis, mol. nanotechnol. and biotechnol. Mol. vibrations provide a valuable fingerprint' for such identification. Vibrational spectroscopy based on tip-enhanced Raman scattering allows us to access the spectral signals of mol. species very efficiently via the strong localized plasmonic fields produced at the tip apex. However, the best spatial resoln. of the tip-enhanced Raman scattering imaging is still limited to 3-15 nm, which is not adequate for resolving a single mol. chem. Here we demonstrate Raman spectral imaging with spatial resoln. below one nanometer, resolving the inner structure and surface configuration of a single mol. This is achieved by spectrally matching the resonance of the nanocavity plasmon to the mol. vibronic transitions, particularly the downward transition responsible for the emission of Raman photons. This matching is made possible by the extremely precise tuning capability provided by scanning tunneling microscopy. Exptl. evidence suggests that the highly confined and broadband nature of the nanocavity plasmon field in the tunnelling gap is essential for ultrahigh-resoln. imaging through the generation of an efficient double-resonance enhancement for both Raman excitation and Raman emission. Our technique not only allows for chem. imaging at the single-mol. level, but also offers a new way to study the optical processes and photochem. of a single mol.
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18. 18
  Zrimsek, A. B.; Chiang, N.; Mattei, M.; Zaleski, S.; McAnally, M. O.; Chapman, C. T.; Henry, A.-I.; Schatz, G. C.; Van Duyne, R. P. Single-molecule chemistry with surface-and tip-enhanced Raman spectroscopy. Chem. Rev. 2017, 117 (11), 7583– 7613, DOI: 10.1021/acs.chemrev.6b00552
  [ACS Full Text ], Google Scholar
  There is no corresponding record for this reference.
19. 19
  Kim, H.; Kosuda, K. M.; Van Duyne, R. P.; Stair, P. C. Resonance Raman and surface- and tip-enhanced Raman spectroscopy methods to study solid catalysts and heterogeneous catalytic reactions. Chem. Soc. Rev. 2010, 39 (12), 4820– 4844, DOI: 10.1039/c0cs00044b
  [Crossref], [PubMed], [CAS], Google Scholar
  19
  Resonance Raman and surface- and tip-enhanced Raman spectroscopy methods to study solid catalysts and heterogeneous catalytic reactions
  Kim, Hacksung; Kosuda, Kathryn M.; Van Duyne, Richard P.; Stair, Peter C.
  Chemical Society Reviews (2010), 39 (12), 4820-4844CODEN: CSRVBR; ISSN:0306-0012. (Royal Society of Chemistry)
  A review. Resonance Raman (RR) spectroscopy has several advantages over the normal Raman spectroscopy (RS) widely used for in situ characterization of solid catalysts and catalytic reactions. Compared with RS, RR can provide much higher sensitivity and selectivity in detecting catalytically-significant surface metal oxides. RR can potentially give useful information on the nature of excited states relevant to photocatalysis and on the anharmonic potential of the ground state. In this crit. review a detailed discussion is presented on several types of RR exptl. systems, 3 distinct sources of so-called Raman (fluorescence) background, detection limits for RR compared to other techniques (EXAFS, PM-IRAS, SFG), and 3 well-known methods to assign UV-vis absorption bands and a band-specific unified method that is derived mainly from RR results. In addn., the virtues and challenges of surface-enhanced Raman spectroscopy (SERS) are discussed for detecting mol. adsorbates at catalytically relevant interfaces. Tip-enhanced Raman spectroscopy (TERS), which is a combination of SERS and near-field scanning probe microscopy and has the capability of probing mol. adsorbates at specific catalytic sites with an enormous surface sensitivity and nanometer spatial resoln., is also reviewed.
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20. 20
  Hartman, T.; Wondergem, C. S.; Kumar, N.; van den Berg, A.; Weckhuysen, B. M. Surface-and tip-enhanced Raman spectroscopy in catalysis. J. Phys. Chem. Lett. 2016, 7 (8), 1570– 1584, DOI: 10.1021/acs.jpclett.6b00147
  [ACS Full Text ], [CAS], Google Scholar
  20
  Surface- and Tip-Enhanced Raman Spectroscopy in Catalysis
  Hartman, Thomas; Wondergem, Caterina S.; Kumar, Naresh; van den Berg, Albert; Weckhuysen, Bert M.
  Journal of Physical Chemistry Letters (2016), 7 (8), 1570-1584CODEN: JPCLCD; ISSN:1948-7185. (American Chemical Society)
  A review; surface- and tip-enhanced Raman spectroscopy (SERS and TERS) techniques exhibit highly localized chem. sensitivity, making them ideal for studying chem. reactions, including processes at catalytic surfaces. Catalyst structures, adsorbates, and reaction intermediates can be obsd. in low quantities at hot spots where electromagnetic fields are the strongest, providing ample opportunities to elucidate reaction mechanisms. Moreover, under ideal measurement conditions, it can even be used to trigger chem. reactions. However, factors such as substrate instability and insufficient signal enhancement still limit the applicability of SERS and TERS in the field of catalysis. By the use of sophisticated colloidal synthesis methods and advanced techniques, such as shell-isolated nanoparticle-enhanced Raman spectroscopy, these challenges could be overcome.
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21. 21
  Domke, K. F.; Pettinger, B. In situ discrimination between axially complexed and ligand-free Co porphyrin on Au(111) with tip-enhanced Raman spectroscopy. ChemPhysChem 2009, 10 (11), 1794– 1798, DOI: 10.1002/cphc.200900182
  [Crossref], [PubMed], [CAS], Google Scholar
  21
  In Situ Discrimination between Axially Complexed and Ligand-Free Co Porphyrin on Au(111) with Tip-Enhanced Raman Spectroscopy
  Domke, Katrin F.; Pettinger, Bruno
  ChemPhysChem (2009), 10 (11), 1794-1798CODEN: CPCHFT; ISSN:1439-4235. (Wiley-VCH Verlag GmbH & Co. KGaA)
  Simultaneous chem. and topog. information about cobalt tetraphenyl-porphyrin (CoTPP) adlayers formed on a Au(111) single crystal is obtained with tip-enhanced Raman (TER) spectroscopy. We distinguish in situ between sample areas covered with an ordered adlayer of CoTPP and areas covered with a spontaneously formed disordered phase. The Raman vibrational fingerprints collected from the nanometer-sized near-field region just below a scanning tunnelling microscope (STM) tip are correlated with the adsorbate structures seen in the STM images. We assign the TER spectral features of the disordered phase to CoTPP complexes with CO and/or NO axial ligands, whereas the TER spectrum obtained from the ordered phase does not show any indication of addnl. axial complexation of CoTPP.
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22. 22
  van Schrojenstein Lantman, E. M.; Deckert-Gaudig, T.; Mank, A. J. G.; Deckert, V.; Weckhuysen, B. M. Catalytic processes monitored at the nanoscale with tip-enhanced Raman spectroscopy. Nat. Nanotechnol. 2012, 7 (9), 583– 586, DOI: 10.1038/nnano.2012.131
  [Crossref], [PubMed], [CAS], Google Scholar
  22
  Catalytic processes monitored at the nanoscale with tip-enhanced Raman spectroscopy
  van Schrojenstein Lantman, Evelien M.; Deckert-Gaudig, Tanja; Mank, Arjan J. G.; Deckert, Volker; Weckhuysen, Bert M.
  Nature Nanotechnology (2012), 7 (9), 583-586CODEN: NNAABX; ISSN:1748-3387. (Nature Publishing Group)
  Heterogeneous catalysts play a pivotal role in the chem. industry, but acquiring mol. insights into functioning catalysts remains a significant challenge. Recent advances in micro-spectroscopic approaches have allowed spatiotemporal information to be obtained on the dynamics of single active sites and the diffusion of single mols. However, these methods lack nanometer-scale spatial resoln. and/or require the use of fluorescent labels. Here, we show that time-resolved tip-enhanced Raman spectroscopy can monitor photocatalytic reactions at the nanoscale. We use a silver-coated at. force microscope tip to both enhance the Raman signal and to act as the catalyst. The tip is placed in contact with a self-assembled monolayer of p-nitrothiophenol mols. adsorbed on gold nanoplates. A photocatalytic redn. process is induced at the apex of the tip with green laser light, while red laser light is used to monitor the transformation process during the reaction. This dual-wavelength approach can also be used to observe other mol. effects such as monolayer diffusion.
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23. 23
  Kumar, N.; Stephanidis, B.; Zenobi, R.; Wain, A.; Roy, D. Nanoscale mapping of catalytic activity using tip-enhanced Raman spectroscopy. Nanoscale 2015, 7 (16), 7133– 7137, DOI: 10.1039/C4NR07441F
  [Crossref], [PubMed], [CAS], Google Scholar
  23
  Nanoscale mapping of catalytic activity using tip-enhanced Raman spectroscopy
  Kumar, N.; Stephanidis, B.; Zenobi, R.; Wain, A. J.; Roy, D.
  Nanoscale (2015), 7 (16), 7133-7137CODEN: NANOHL; ISSN:2040-3372. (Royal Society of Chemistry)
  Chem.mapping of a photocatalytic reaction with nanoscale spatial resoln.is demonstrated for the first time using tip-enhanced Raman spectroscopy (TERS). An ultrathin alumina film applied to the Ag-coated TERS tip blocks catalytic interference while maintaining near-field electromagnetic enhancement, thus enabling spectroscopic imaging of catalytic activity on nanostructured Ag surfaces.
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24. 24
  Zhong, J.-H.; Jin, X.; Meng, L.; Wang, X.; Su, H.-S.; Yang, Z.-L.; Williams, C. T.; Ren, B. Probing the electronic and catalytic properties of a bimetallic surface with 3 nm resolution. Nat. Nanotechnol. 2016, 12 (2), 132– 136, DOI: 10.1038/nnano.2016.241
  [Crossref], [PubMed], Google Scholar
  There is no corresponding record for this reference.
25. 25
  Martín Sabanés, N.; Driessen, L. M.; Domke, K. F. Versatile side-illumination geometry for tip-enhanced Raman spectroscopy at solid/liquid interfaces. Anal. Chem. 2016, 88 (14), 7108– 7114, DOI: 10.1021/acs.analchem.6b01080
  [ACS Full Text ], [CAS], Google Scholar
  25
  Versatile Side-Illumination Geometry for Tip-Enhanced Raman Spectroscopy at Solid/Liquid Interfaces
  Martin Sabanes, Natalia; Driessen, Leonie M. A.; Domke, Katrin F.
  Analytical Chemistry (Washington, DC, United States) (2016), 88 (14), 7108-7114CODEN: ANCHAM; ISSN:0003-2700. (American Chemical Society)
  In situ characterization of surfaces with tip-enhanced Raman spectroscopy (TERS) provides chem. and topog. information with high spatial resoln. and submonolayer chem. sensitivity. To further the versatility of the TERS approach toward more complex systems such as biol. membranes or energy conversion devices, adaptation of the technique to solid/liq. working conditions is essential. Here, we present a home-built side-illumination TERS setup design based on a com. scanning tunneling microscope (STM) as a versatile, cost-efficient soln. for TERS at solid/liq. interfaces. Interestingly, the results obtained from showcase resonant dye and nonresonant thiophenol monolayers adsorbed on Au single crystals suggest that excitation beam aberrations due to the presence of the aq. phase are small enough not to limit TER signal detection. The STM parameters are found to play a crucial role for solid/liq. TERS sensitivity. Raman enhancement factors of 105 at μW laser power demonstrate the great potential the presented exptl. configuration holds for solid/liq. interfacial spectroscopic studies.
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26. 26
  Martín Sabanés, N.; Ohto, T.; Andrienko, D.; Nagata, Y.; Domke, K. F. Electrochemical TERS elucidates potential-induced molecular reorientation of adenine/Au(111). Angew. Chem., Int. Ed. 2017, 56 (33), 9796– 9801, DOI: 10.1002/anie.201704460
  [Crossref], [CAS], Google Scholar
  26
  Electrochemical TERS Elucidates Potential-Induced Molecular Reorientation of Adenine/Au(111)
  Martin Sabanes, Natalia; Ohto, Tatsuhiko; Andrienko, Denis; Nagata, Yuki; Domke, Katrin F.
  Angewandte Chemie, International Edition (2017), 56 (33), 9796-9801CODEN: ACIEF5; ISSN:1433-7851. (Wiley-VCH Verlag GmbH & Co. KGaA)
  Electrochem. surface activity arises from the interaction and geometric arrangement of mols. at electrified interfaces. The authors present a novel electrochem. tip-enhanced Raman spectroscope that can access the vibrational fingerprint of <100 small, nonresonant mols. adsorbed at atomically flat Au electrodes to study their adsorption geometry and chem. reactivity as a function of the applied potential. Combining exptl. and simulation data for adenine/Au(111), protonated physisorbed adenine adopts a tilted orientation at low potentials, whereas it is vertically adsorbed around the potential of zero charge. Further potential increase induces adenine deprotonation and reorientation to a planar configuration. The extension of EC-TERS to the study of adsorbate reorientation significantly broadens the applicability of this advanced spectroelectrochem. tool for the nanoscale characterization of a full range of electrochem. interfaces.
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27. 27
  Mattei, M.; Kang, G.; Goubert, G.; Chulhai, D. V.; Schatz, G. C.; Jensen, L.; Van Duyne, R. P. Tip-enhanced Raman voltammetry: Coverage dependence and quantitative modeling. Nano Lett. 2017, 17 (1), 590– 596, DOI: 10.1021/acs.nanolett.6b04868
  [ACS Full Text ], Google Scholar
  There is no corresponding record for this reference.
28. 28
  Kumar, N.; Kalirai, S.; Wain, A. J.; Weckhuysen, B. M. Nanoscale chemical imaging of a single catalyst particle with tip-enhanced fluorescence microscopy. ChemCatChem 2019, 11 (1), 417– 423, DOI: 10.1002/cctc.201801023
  [Crossref], [PubMed], [CAS], Google Scholar
  28
  Nanoscale Chemical Imaging of a Single Catalyst Particle with Tip-Enhanced Fluorescence Microscopy
  Kumar, Naresh; Kalirai, Sam; Wain, Andrew J.; Weckhuysen, Bert M.
  ChemCatChem (2019), 11 (1), 417-423CODEN: CHEMK3; ISSN:1867-3880. (Wiley-VCH Verlag GmbH & Co. KGaA)
  Detg. the active site in real-life solid catalysts remains an intellectual challenge and is crucial for exploring the road towards their rational design. In recent years various micro-spectroscopic methods have revealed valuable structure-activity data at the level of a single catalyst particle, even under reaction conditions.. Herein, we introduce Tip-Enhanced FLuorescence (TEFL) microscopy as a novel and versatile characterization tool for catalysis research. This has been achieved using a Fluid Catalytic Cracking (FCC) catalyst as showcase material. Thin sectioning of industrially used FCC particles together with selective staining of Bronsted acidity has enabled high-resoln. TEFL mapping of different catalyst regions. Hyperspectral information gained via TEFL microscopy reveals a spatial distribution of Bronsted acidity within individual zeolite domains in different regions of the FCC catalyst particle. Comparison of TEFL measurements from different FCC particles showed significant intra- and inter-particle heterogeneities both in zeolite domain size and chem. reactivity.
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29. 29
  Schmid, T.; Yeo, B. S.; Leong, G.; Stadler, J.; Zenobi, R. Performing tip-enhanced Raman spectroscopy in liquids. J. Raman Spectrosc. 2009, 40 (10), 1392– 1399, DOI: 10.1002/jrs.2387
  [Crossref], Google Scholar
  There is no corresponding record for this reference.
30. 30
  Scherger, J. D.; Foster, M. D. Tunable, liquid resistant tip-enhanced Raman spectroscopy probes: Toward label-free nano-resolved imaging of biological systems. Langmuir 2017, 33 (31), 7818– 7825, DOI: 10.1021/acs.langmuir.7b01338
  [ACS Full Text ], [CAS], Google Scholar
  30
  Tunable, Liquid Resistant Tip Enhanced Raman Spectroscopy Probes: Toward Label-Free Nano-Resolved Imaging of Biological Systems
  Scherger, Jacob D.; Foster, Mark D.
  Langmuir (2017), 33 (31), 7818-7825CODEN: LANGD5; ISSN:0743-7463. (American Chemical Society)
  Tip enhanced Raman spectroscopy (TERS) has been established as a powerful, noninvasive technique for chem. identification at the nanoscale. However, difficulties, including the degrdn. of probes, limit its use in liq. systems. Here TERS probes for studies in aq. environments have been demonstrated using titanium nitride coatings with an alumina protective layer. The probes show enhancement in signal intensity as high as 380% in liq. measurements, and the probe resonance can be tuned by varying deposition conditions to optimize performance for different laser sources and types of samples. This development of inexpensively produced probes suited for studies in aq. environments enables its wider use for fields such as biol. and biomedicine in which aq. environments are the norm.
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31. 31
  Touzalin, T.; Dauphin, A. L.; Joiret, S.; Lucas, I. T.; Maisonhaute, E. Tip-enhanced Raman spectroscopy imaging of opaque samples in organic liquid. Phys. Chem. Chem. Phys. 2016, 18 (23), 15510– 15513, DOI: 10.1039/C6CP02596J
  [Crossref], Google Scholar
  There is no corresponding record for this reference.
32. 32
  Zeng, Z.-C.; Huang, S.-C.; Wu, D.-Y.; Meng, L.-Y.; Li, M.-H.; Huang, T.-X.; Zhong, J.-H.; Wang, X.; Yang, Z.-L.; Ren, B. Electrochemical tip-enhanced Raman spectroscopy. J. Am. Chem. Soc. 2015, 137 (37), 11928– 11931, DOI: 10.1021/jacs.5b08143
  [ACS Full Text ], [CAS], Google Scholar
  32
  Electrochemical Tip-Enhanced Raman Spectroscopy
  Zeng, Zhi-Cong; Huang, Sheng-Chao; Wu, De-Yin; Meng, Ling-Yan; Li, Mao-Hua; Huang, Teng-Xiang; Zhong, Jin-Hui; Wang, Xiang; Yang, Zhi-Lin; Ren, Bin
  Journal of the American Chemical Society (2015), 137 (37), 11928-11931CODEN: JACSAT; ISSN:0002-7863. (American Chemical Society)
  Interfacial properties are highly important to the performance of some energy-related systems. The in-depth understanding of the interface requires highly sensitive in situ techniques that can provide fingerprint mol. information at nanometer resoln. The authors developed an electrochem. tip-enhanced Raman spectroscopy (EC-TERS) by introduction of the light horizontally to the EC-STM cell to minimize the optical distortion and to keep the TERS measurement under a well-controlled condition. The authors obtained potential-dependent EC-TERS from the adsorbed arom. mol. on a Au(111) surface and obsd. a substantial change in the mol. configuration with potential as a result of the protonation and deprotonation of the mol. Such a change was not observable in EC-SERS (surface-enhanced), indicating EC-TERS can more faithfully reflect the fine interfacial structure than EC-SERS. This work will open a new era for using EC-TERS as an important nanospectroscopy tool for the mol. level and nanoscale anal. of some important electrochem. systems including solar cells, lithium ion batteries, fuel cells, and corrosion.
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33. 33
  Kurouski, D.; Mattei, M.; Van Duyne, R. P. Probing redox reactions at the nanoscale with electrochemical tip-enhanced Raman spectroscopy. Nano Lett. 2015, 15 (12), 7956– 7962, DOI: 10.1021/acs.nanolett.5b04177
  [ACS Full Text ], [CAS], Google Scholar
  33
  Probing Redox Reactions at the Nanoscale with Electrochemical Tip-Enhanced Raman Spectroscopy
  Kurouski, Dmitry; Mattei, Michael; Van Duyne, Richard P.
  Nano Letters (2015), 15 (12), 7956-7962CODEN: NALEFD; ISSN:1530-6984. (American Chemical Society)
  A fundamental understanding of electrochem. processes at the nanoscale is crucial to solving problems in research areas as diverse as electrocatalysis, energy storage, biol. electron transfer, and plasmon-driven chem. However, there is currently no technique capable of directly providing chem. information about mols. undergoing heterogeneous charge transfer at the nanoscale. Tip-enhanced Raman spectroscopy (TERS) uniquely offers subnanometer spatial resoln. and single-mol. sensitivity, making it the ideal tool for studying nanoscale electrochem. processes with high chem. specificity. The authors demonstrate the 1st electrochem. TERS (EC-TERS) study of the nanoscale redox behavior of Nile Blue (NB), and compare these results with conventional cyclic voltammetry (CV). The authors successfully monitor the disappearance of the 591 cm-1 band of NB upon redn. and its reversible reappearance upon oxidn. during the CV. The authors observe a neg. shift of >100 mV in the onset of the potential response of the TERS intensity of the 591 cm-1 band, compared to the onset of faradaic current in the CV. The authors hypothesize that perturbation of the elec. double-layer by the TERS tip locally alters the effective potential experienced by NB mols. in the tip-sample junction. However, the tip has no effect on the local charge transfer kinetics. Addnl., the authors observe step-like behavior in some TERS voltammograms corresponding to redn. and oxidn. of single or few NB mols. Also the coverage of NB is nonuniform across the ITO surface. The authors conclude with a discussion of methods to overcome the perturbation of the double-layer and general considerations for using TERS to study nanoscale electrochem. processes.
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34. 34
  Kumar, N.; Su, W.; Vesely, M.; Weckhuysen, B. M.; Pollard, A. J.; Wain, A. J. Nanoscale chemical imaging of solid-liquid interfaces using tip-enhanced Raman spectroscopy. Nanoscale 2018, 10 (4), 1815– 1824, DOI: 10.1039/C7NR08257F
  [Crossref], [PubMed], [CAS], Google Scholar
  34
  Nanoscale chemical imaging of solid-liquid interfaces using tip-enhanced Raman spectroscopy
  Kumar, Naresh; Su, Weitao; Vesely, Martin; Weckhuysen, Bert M.; Pollard, Andrew J.; Wain, Andrew J.
  Nanoscale (2018), 10 (4), 1815-1824CODEN: NANOHL; ISSN:2040-3372. (Royal Society of Chemistry)
  Tip-enhanced Raman spectroscopy (TERS) is a powerful tool for non-destructive and label-free surface mol. mapping at the nanoscale. However, to date nanoscale resoln. chem. imaging in a liq. environment has not been possible, in part due to the lack of robust TERS probes that are stable when immersed in a liq. In this work, we have addressed this challenge by developing plasmonically-active TERS probes with a multilayer metal coating structure that can be successfully used within a liq. environment. Using these novel TERS probes, we have compared the plasmonic enhancement of TERS signals in air and water environments for both gap mode and non-gap mode configurations and show that in both cases the plasmonic enhancement decreases in water. To better understand the signal attenuation in water, we have performed numerical simulations that revealed a neg. correlation between the elec. field enhancement at the TERS probe-apex and the refractive index of the surrounding medium. Finally, using these robust probes we demonstrate TERS imaging with nanoscale spatial resoln. in a water environment for the first time by employing single-wall carbon nanotubes as a model sample. Our findings are expected to broaden the scope of TERS to a range of scientific disciplines in which nanostructured solid-liq. interfaces play a key role.
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35. 35
  Su, W.; Kumar, N.; Mignuzzi, S.; Crain, J.; Roy, D. Nanoscale mapping of excitonic processes in single-layer MoS 2 using tip-enhanced photoluminescence microscopy. Nanoscale 2016, 8 (20), 10564– 10569, DOI: 10.1039/C5NR07378B
  [Crossref], [PubMed], [CAS], Google Scholar
  35
  Nanoscale mapping of excitonic processes in single-layer MoS2 using tip-enhanced photoluminescence microscopy
  Su, Weitao; Kumar, Naresh; Mignuzzi, Sandro; Crain, Jason; Roy, Debdulal
  Nanoscale (2016), 8 (20), 10564-10569CODEN: NANOHL; ISSN:2040-3372. (Royal Society of Chemistry)
  In two-dimensional (2D) semiconductors, photoluminescence originating from recombination processes involving neutral electron-hole pairs (excitons) and charged complexes (trions) is strongly affected by the localized charge transfer due to inhomogeneous interactions with the local environment and surface defects. Herein, we demonstrate the first nanoscale mapping of excitons and trions in single-layer MoS2 using the full spectral information obtained via tip-enhanced photoluminescence (TEPL) microscopy along with tip-enhanced Raman spectroscopy (TERS) imaging of a 2D flake. Finally, we show the mapping of the PL quenching center in single-layer MoS2 with an unprecedented spatial resoln. of 20 nm. In addn., our research shows that unlike in aperture-scanning near field microscopy, preferential exciton emission mapping at the nanoscale using TEPL and Raman mapping using TERS can be obtained simultaneously using this method that can be used to correlate the structural and excitonic properties.
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36. 36
  Kumar, N.; Spencer, S. J.; Imbraguglio, D.; Rossi, A. M.; Wain, A. J.; Weckhuysen, B. M.; Roy, D. Extending the plasmonic lifetime of tip-enhanced Raman spectroscopy probes. Phys. Chem. Chem. Phys. 2016, 18 (19), 13710– 13716, DOI: 10.1039/C6CP01641C
  [Crossref], [PubMed], [CAS], Google Scholar
  36
  Extending the plasmonic lifetime of tip-enhanced Raman spectroscopy probes
  Kumar, Naresh; Spencer, Steve J.; Imbraguglio, Dario; Rossi, Andrea M.; Wain, Andrew J.; Weckhuysen, Bert M.; Roy, Debdulal
  Physical Chemistry Chemical Physics (2016), 18 (19), 13710-13716CODEN: PPCPFQ; ISSN:1463-9076. (Royal Society of Chemistry)
  Tip-enhanced Raman spectroscopy (TERS) is an emerging technique for simultaneous mapping of chem. compn. and topog. of a surface at the nanoscale. However, rapid degrdn. of TERS probes, esp. those coated with silver, is a major bottleneck to the widespread uptake of this technique and severely prohibits the success of many TERS expts. In this work, we carry out a systematic time-series study of the plasmonic degrdn. of Ag-coated TERS probes under different environmental conditions and demonstrate that a low oxygen (<1 ppm) and a low moisture (<1 ppm) environment can significantly improve the plasmonic lifetime of TERS probes from a few hours to a few months. Furthermore, using XPS measurements on Ag nanoparticles we show that the rapid plasmonic degrdn. of Ag-coated TERS probes can be correlated to surface oxide formation. Finally, we present practical guidelines for the effective use and storage of TERS probes to improve their plasmonic lifetime based on the results of this study.
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37. 37
  Kalbacova, J.; Rodriguez, R. D.; Desale, V.; Schneider, M.; Amin, I.; Jordan, R.; Zahn, D. R. Chemical stability of plasmon-active silver tips for tip-enhanced Raman spectroscopy. Nanospectroscopy 2015, 1, 12– 18, DOI: 10.2478/nansp-2014-0002
  [Crossref], Google Scholar
  There is no corresponding record for this reference.
38. 38
  Opilik, L.; Dogan, Ü.; Szczerbiński, J.; Zenobi, R. Degradation of silver near-field optical probes and its electrochemical reversal. Appl. Phys. Lett. 2015, 107 (9), 091109, DOI: 10.1063/1.4929880
  [Crossref], [CAS], Google Scholar
  38
  Degradation of silver near-field optical probes and its electrochemical reversal
  Opilik, Lothar; Dogan, Uzeyir; Szczerbinski, Jacek; Zenobi, Renato
  Applied Physics Letters (2015), 107 (9), 091109/1-091109/5CODEN: APPLAB; ISSN:0003-6951. (American Institute of Physics)
  Deterioration of the outstanding optical properties of elemental silver due to atm. corrosion compromises its use in the field of plasmonics. Therefore, more chem. inert, but more lossy, metals (e.g., gold) are often used as a compromise. Silver tips for near-field optical microscopy are only utilized by specialized labs. with inhouse tip prodn. facilities. This article presents a time-dependent study of the effect of atm. corrosion on the electromagnetic enhancement of solid silver tips. It was found that chem. degrdn. renders them unusable for tip-enhanced Raman spectroscopy (TERS) within the first two days after prodn. Furthermore, we present a simple electrochem. method for recovering the enhancing effect of corroded silver tips, as well as for storing freshly prepd. probes, for example, for easy shipment. The present work greatly simplifies the exptl. aspects of near-field optical microscopy, which should make near-field optical techniques, and, in particular, TERS, more accessible to the scientific community. (c) 2015 American Institute of Physics.
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39. 39
  Yeo, B. S.; Stadler, J.; Schmid, T.; Zenobi, R.; Zhang, W. H. Tip-enhanced Raman spectroscopy - Its status, challenges and future directions. Chem. Phys. Lett. 2009, 472 (1–3), 1– 13, DOI: 10.1016/j.cplett.2009.02.023
  [Crossref], [CAS], Google Scholar
  39
  Tip-enhanced Raman Spectroscopy - Its status, challenges and future directions
  Yeo, Boon-Siang; Stadler, Johannes; Schmid, Thomas; Zenobi, Renato; Zhang, Weihua
  Chemical Physics Letters (2009), 472 (1-3), 1-13CODEN: CHPLBC; ISSN:0009-2614. (Elsevier B.V.)
  A review. Tip-enhanced Raman Spectroscopy (TERS) showed promise as a tool for in situ nanoscale chem. anal., and is also leading to a better understanding of the fundamentals of surface-enhanced Raman Spectroscopy. The latest developments, challenges and applications of TERS are discussed. The focus is on tip plasmonics, single mol. detection and nanoscale chem. anal. of biol. samples.
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40. 40
  Barrios, C. A.; Malkovskiy, A. V.; Kisliuk, A. M.; Sokolov, A. P.; Foster, M. D. Highly stable, protected plasmonic nanostructures for tip-enhanced Raman spectroscopy. J. Phys. Chem. C 2009, 113 (19), 8158– 8161, DOI: 10.1021/jp8098126
  [ACS Full Text ], Google Scholar
  There is no corresponding record for this reference.
41. 41
  Opilik, L.; Dogan, U. z.; Li, C.-Y.; Stephanidis, B.; Li, J.-F.; Zenobi, R. Chemical production of thin protective coatings on optical nanotips for tip-enhanced Raman spectroscopy. J. Phys. Chem. C 2016, 120 (37), 20828– 20832, DOI: 10.1021/acs.jpcc.6b02147
  [ACS Full Text ], [CAS], Google Scholar
  41
  Chemical Production of Thin Protective Coatings on Optical Nanotips for Tip-Enhanced Raman Spectroscopy
  Opilik, Lothar; Dogan, Uzeyir; Li, Chao-Yu; Stephanidis, Bruno; Li, Jian-Feng; Zenobi, Renato
  Journal of Physical Chemistry C (2016), 120 (37), 20828-20832CODEN: JPCCCK; ISSN:1932-7447. (American Chemical Society)
  Tip-enhanced Raman spectroscopy (TERS) provides topog. and chem. information simultaneously with a spatial resoln. well below the optical diffraction limit; however, the typically used noble-metal nanotips are prone to unwanted chemisorption, and when silver is used, the enhancement quickly fades due to chem. degrdn. during storage and use. In the present work, we demonstrate a method to produce strongly enhancing tips for TERS, which are protected against undesired chemisorption and (in the case of silver) have a significantly longer lifetime than unprotected tips. This was achieved by chem. coating of an ultrathin (few nanometers) and pinhole-free silica shell on top of the enhancing noble-metal nanostructures. The enhancement achieved with the protected silver tips was comparable with the typical tip enhancement for TERS; i.e., no major constraints for TERS expts. resulted from the protective coatings. These shell-isolated tips could widen the scope of tip-enhanced Raman spectroscopy by potentially allowing for in situ studies of, for example, surface catalysis and biol. systems.
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42. 42
  Pourbaix, M. Atlas of Electrochemical Equilibria in Aqueous Solutions; National Association of Corrosion Engineers: Houston, TX, 1974.
  Google Scholar
  There is no corresponding record for this reference.
43. 43
  Huang, Y.-P. Shell-isolated tip-enhanced Raman and fluorescence spectroscopy. Angew. Chem., Int. Ed. 2018, 57 (25), 7523– 7527, DOI: 10.1002/anie.201802892
  [Crossref], [CAS], Google Scholar
  43
  Shell-Isolated Tip-Enhanced Raman and Fluorescence Spectroscopy
  Huang, Ya-Ping; Huang, Sheng-Chao; Wang, Xiang-Jie; Bodappa, Nataraju; Li, Chao-Yu; Yin, Hao; Su, Hai-Sheng; Meng, Meng; Zhang, Hua; Ren, Bin; Yang, Zhi-Lin; Zenobi, Renato; Tian, Zhong-Qun; Li, Jian-Feng
  Angewandte Chemie, International Edition (2018), 57 (25), 7523-7527CODEN: ACIEF5; ISSN:1433-7851. (Wiley-VCH Verlag GmbH & Co. KGaA)
  Tip-enhanced Raman spectroscopy can provide mol. fingerprint information with ultrahigh spatial resoln., but the tip will be easily contaminated, thus leading to artifacts. It also remains a great challenge to establish tip-enhanced fluorescence because of the quenching resulting from the proximity of the metal tip. Herein, we report shell-isolated tip-enhanced Raman and fluorescence spectroscopies by employing ultrathin shell-isolated tips fabricated by at. layer deposition. Such shell-isolated tips not only show outstanding electromagnetic field enhancement in TERS but also exclude interference by contaminants, thus greatly promoting applications in soln. Tip-enhanced fluorescence has also been achieved using these shell-isolated tips, with enhancement factors of up to 1.7×103, consistent with theor. simulations. Furthermore, tip-enhanced Raman and fluorescence signals are acquired simultaneously, and their relative intensities can be manipulated by changing the shell thickness. This work opens a new avenue for ultrahigh resoln. surface anal. using plasmon-enhanced spectroscopies.
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44. 44
  Vaidya, P. D.; Lopez-Sanchez, J. A. Review of hydrogen production by catalytic aqueous-phase reforming. ChemistrySelect 2017, 2 (22), 6563– 6576, DOI: 10.1002/slct.201700905
  [Crossref], Google Scholar
  There is no corresponding record for this reference.
45. 45
  Navarro, R. M.; Pena, M.; Fierro, J. Hydrogen production reactions from carbon feedstocks: fossil fuels and biomass. Chem. Rev. 2007, 107 (10), 3952– 3991, DOI: 10.1021/cr0501994
  [ACS Full Text ], [CAS], Google Scholar
  45
  Hydrogen Production Reactions from Carbon Feedstocks: Fossil Fuels and Biomass
  Navarro, R. M.; Pena, M. A.; Fierro, J. L. G.
  Chemical Reviews (Washington, DC, United States) (2007), 107 (10), 3952-3991CODEN: CHREAY; ISSN:0009-2665. (American Chemical Society)
  A review. The fuel cell technol., as well as the prodn. of ammonia and other traditional used, required large amts. of H2. Feedstocks for H2 are methane, liq. hydrocarbons, methanol, coal, biomass and biomass derived products. The common processes to produce H2 from these feeds are steam reforming, partial and autothermal oxidn., catalytic decompn. of CH4, CH4 aromatization, and gasification of biomass in supercrit. water.
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46. 46
  Huang, Y.-F.; Zhu, H.-P.; Liu, G.-K.; Wu, D.-Y.; Ren, B.; Tian, Z.-Q. When the signal is not from the original molecule to be detected: chemical transformation of para-aminothiophenol on Ag during the SERS measurement. J. Am. Chem. Soc. 2010, 132 (27), 9244– 9246, DOI: 10.1021/ja101107z
  [ACS Full Text ], [CAS], Google Scholar
  46
  When the signal is not from the original molecule to be detected: chemical transformation of para-aminothiophenol on Ag during the SERS measurement
  Huang, Yi-Fan; Zhu, Hong-Ping; Liu, Guo-Kun; Wu, De-Yin; Ren, Bin; Tian, Zhong-Qun
  Journal of the American Chemical Society (2010), 132 (27), 9244-9246CODEN: JACSAT; ISSN:0002-7863. (American Chemical Society)
  Surface-enhanced Raman spectroscopy (SERS) has long been considered as a noninvasive technique that can obtain the fingerprint vibrational information of surface species. We demonstrated in this paper that a laser with a power level considered to be low in the traditional SERS measurement can already lead to a significant surface reaction. para-Aminothiophenol, an important probe mol. in SERS, was found to be oxidized to form 4,4'-dimercaptoazobenzene (DMAB) on a roughened silver surface during the SERS measurement. The assumption was confirmed exptl. by surface mass spectroscopy and SERS as well as electrochem. of the synthesized DMAB, which agrees well with theor. calcns. A defocusing method was used to avoid the laser induced surface reaction and perform reliable SERS characterization and identification, which can effectively avoid erroneous interpretation of the distorted exptl. result.
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47. 47
  Mehtani, D.; Lee, N.; Hartschuh, R.; Kisliuk, A.; Foster, M.; Sokolov, A.; Čajko, F.; Tsukerman, I. Optical properties and enhancement factors of the tips for apertureless near-field optics. J. Opt. A: Pure Appl. Opt. 2006, 8 (4), S183– S190, DOI: 10.1088/1464-4258/8/4/S19
  [Crossref], Google Scholar
  There is no corresponding record for this reference.
48. 48
  Agapov, R. L.; Malkovskiy, A. V.; Sokolov, A. P.; Foster, M. D. Prolonged blinking with TERS probes. J. Phys. Chem. C 2011, 115 (18), 8900– 8905, DOI: 10.1021/jp111762u
  [ACS Full Text ], Google Scholar
  There is no corresponding record for this reference.
49. 49
  Kumar, N.; Rae, A.; Roy, D. Accurate measurement of enhancement factor in tip-enhanced Raman spectroscopy through elimination of far-field artefacts. Appl. Phys. Lett. 2014, 104 (12), 123106, DOI: 10.1063/1.4869184
  [Crossref], Google Scholar
  There is no corresponding record for this reference.
50. 50
  Zhang, Z.; Merk, V.; Hermanns, A.; Unger, W. E. S.; Kneipp, J. Role of metal cations in plasmon-catalyzed oxidation: A case study of p-aminothiophenol dimerization. ACS Catal. 2017, 7 (11), 7803– 7809, DOI: 10.1021/acscatal.7b02700
  [ACS Full Text ], [CAS], Google Scholar
  50
  Role of Metal Cations in Plasmon-Catalyzed Oxidation: A Case Study of p-Aminothiophenol Dimerization
  Zhang, Zhiyang; Merk, Virginia; Hermanns, Anja; Unger, Wolfgang E. S.; Kneipp, Janina
  ACS Catalysis (2017), 7 (11), 7803-7809CODEN: ACCACS; ISSN:2155-5435. (American Chemical Society)
  The mechanism of the plasmon-catalyzed reaction of p-aminothiophenol (PATP) to 4,4'-dimercaptoazobenzene (DMAB) on the surface of metal nanoparticles has been discussed using data from surface-enhanced Raman scattering of DMAB. Oxides and hydroxides formed in a plasmon-catalyzed process were proposed to play a central role in the reaction. Here, we report DMAB formation on gold nanoparticles occurring in the presence of the metal cations Ag+, Au3+, Pt4+, and Hg2+. The expts. were carried out under conditions where formation of gold oxide or hydroxide from the nanoparticles can be excluded and at high pH where the formation of the corresponding oxidic species from the metal ions is favored. On the basis of our results, we conclude that, under these conditions, the selective oxidn. of PATP to DMAB takes place via formation of a metal oxide from the ionic species in a plasmon-catalyzed process. By evidencing the necessity of the presence of the metal cations, the reported results underpin the importance of metal oxides in the reaction.
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51. 51
  Zhao, L. B.; Zhang, M.; Huang, Y. F.; Williams, C. T.; Wu, D. Y.; Ren, B.; Tian, Z. Q. Theoretical study of plasmon-enhanced surface catalytic coupling reactions of aromatic amines and nitro compounds. J. Phys. Chem. Lett. 2014, 5 (7), 1259– 1266, DOI: 10.1021/jz5003346
  [ACS Full Text ], [CAS], Google Scholar
  51
  Theoretical Study of Plasmon-Enhanced Surface Catalytic Coupling Reactions of Aromatic Amines and Nitro Compounds
  Zhao, Liu-Bin; Zhang, Meng; Huang, Yi-Fan; Williams, Christopher T.; Wu, De-Yin; Ren, Bin; Tian, Zhong-Qun
  Journal of Physical Chemistry Letters (2014), 5 (7), 1259-1266CODEN: JPCLCD; ISSN:1948-7185. (American Chemical Society)
  Taking advantage of the unique capacity of surface plasmon resonance, plasmon-enhanced heterogeneous catalysis has recently come into focus as a promising technique for high performance light-energy conversion. This work performs a theor. study on the reaction mechanism for conversions of p-aminothiophenol (PATP) and p-nitrothiophenol (PNTP) to arom. azo species, p,p'-dimercaptoazobenzene (DMAB). In the absence of O2 or H2, the plasmon-driven photocatalysis mechanism (hot electron-hole reactions) is the major reaction channel. In the presence of O2 or H2, the plasmon-assisted surface catalysis mechanism (activated oxygen/hydrogen reactions) is the major reaction channel. The present results show that the coupling reactions of PATP and PNTP strongly depend on the soln. pH, the irradn. wavelength, the irradn. power, and the nature of metal substrates as well as the surrounding atm. The present study has drawn a fundamental phys. picture for understanding plasmon-enhanced heterogeneous catalysis.
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52. 52
  Mock, J. J.; Smith, D. R.; Schultz, S. Local refractive index dependence of plasmon resonance spectra from individual nanoparticles. Nano Lett. 2003, 3 (4), 485– 491, DOI: 10.1021/nl0340475
  [ACS Full Text ], [CAS], Google Scholar
  52
  Local Refractive Index Dependence of Plasmon Resonance Spectra from Individual Nanoparticles
  Mock, Jack J.; Smith, David R.; Schultz, Sheldon
  Nano Letters (2003), 3 (4), 485-491CODEN: NALEFD; ISSN:1530-6984. (American Chemical Society)
  The authors present an exptl. optical darkfield microscope study of the dependence of the plasmon resonance spectrum of individual Ag nanoparticles on the local index of refraction. The authors systematically characterize the position of the resonance peaks assocd. with the same set of individual Ag nanoparticles embedded sequentially in index oils with increasing refractive index. This technique effectively allows the local refractive index to be stepped in increments of 0.04. As the local index is increased, the spectrum from each of the nanoparticles generally undergoes a very regular and reproducible red shift; however, the amt. of red shift per index increase varies depending on the shape of the nanoparticle and the mode of excitation. In particular, the spectral peak that occurs in triangular nanoparticles exhibits a noticeably larger red shift than that assocd. with the dipole mode corresponding to spherical nanoparticles. The authors' results are consistent with expts. performed on ensembles of similar nanoparticles and suggest that individual nanoparticles may be used in biosensing applications where currently ensembles are being studied.
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53. 53
  Xu, P.; Kang, L.; Mack, N. H.; Schanze, K. S.; Han, X.; Wang, H.-L. Mechanistic understanding of surface plasmon assisted catalysis on a single particle: cyclic redox of 4-aminothiophenol. Sci. Rep. 2013, 3, 2997, DOI: 10.1038/srep02997
  [Crossref], [PubMed], [CAS], Google Scholar
  53
  Mechanistic understanding of surface plasmon assisted catalysis on a single particle: cyclic redox of 4-aminothiophenol
  Xu Ping; Kang Leilei; Mack Nathan H; Schanze Kirk S; Han Xijiang; Wang Hsing-Lin
  Scientific reports (2013), 3 (), 2997 ISSN:.
  Surface plasmon assisted catalysis (SPAC) reactions of 4-aminothiophenol (4ATP) to and back from 4,4'-dimercaptoazobenzene (DMAB) have been investigated by single particle surface enhanced Raman spectroscopy, using a self-designed gas flow cell to control the reductive/oxidative environment over the reactions. Conversion of 4ATP into DMAB is induced by energy transfer (plasmonic heating) from surface plasmon resonance to 4ATP, where O2 (as an electron acceptor) is essential and H2O (as a base) can accelerate the reaction. In contrast, hot electron (from surface plasmon decay) induction drives the reverse reaction of DMAB to 4ATP, where H2O (or H2) acts as the hydrogen source. More interestingly, the cyclic redox between 4ATP and DMAB by SPAC approach has been demonstrated. This SPAC methodology presents a unique platform for studying chemical reactions that are not possible under standard synthetic conditions.
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54. 54
  Sun, M.; Xu, H. A novel application of plasmonics: Plasmon-driven surface-catalyzed reactions. Small 2012, 8 (18), 2777– 2786, DOI: 10.1002/smll.201200572
  [Crossref], [PubMed], [CAS], Google Scholar
  54
  A Novel Application of Plasmonics: Plasmon-Driven Surface-Catalyzed Reactions
  Sun, Mengtao; Xu, Hongxing
  Small (2012), 8 (18), 2777-2786CODEN: SMALBC; ISSN:1613-6810. (Wiley-VCH Verlag GmbH & Co. KGaA)
  A review. The first exptl. and theor. evidence of the surface-catalyzed reaction of p,p'-dimercaptoazobenzene (DMAB) produced from para-aminothiophenol (PATP) by local surface plasmons was reported in 2010, and since that time a series of investigations have supported these findings using different exptl. and theor. methods. Recent work has also found that local plasmons can drive a surface-catalyzed reaction of DMAB converted from 4-nitrobenzenethiol (4NBT), assisted by local surface plasmons. There are at least three important discoveries in these investigations: (1) in the field of surface-enhanced Raman scattering (SERS) the widely accepted misinterpretation (since 1994) that the chem. mechanism resulting in three addnl. Raman peaks of PATP in Ag or Au solns. has been cor. with a new mechanism; (2) it is confirmed that SERS is not always a noninvasive technique, and under certain conditions cannot always obtain the vibrational fingerprint information of the original surface species; (3) a novel method to synthesize new mols., induced by local surface plasmons or plasmon waveguides on the nanoscale, has been found. This Review considers recent novel applications of plasmonics to chem. reactions, esp. to plasmon-driven surface-catalyzed reactions.
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55. 55
  Kang, L.; Xu, P.; Zhang, B.; Tsai, H.; Han, X.; Wang, H.-L. Laser wavelength- and power-dependent plasmon-driven chemical reactions monitored using single particle surface enhanced Raman spectroscopy. Chem. Commun. 2013, 49 (33), 3389– 3391, DOI: 10.1039/c3cc40732b
  [Crossref], [PubMed], [CAS], Google Scholar
  55
  Laser wavelength- and power-dependent plasmon-driven chemical reactions monitored using single particle surface enhanced Raman spectroscopy
  Kang, Leilei; Xu, Ping; Zhang, Bin; Tsai, Hsinhan; Han, Xijiang; Wang, Hsing-Lin
  Chemical Communications (Cambridge, United Kingdom) (2013), 49 (33), 3389-3391CODEN: CHCOFS; ISSN:1359-7345. (Royal Society of Chemistry)
  Plasmon-driven chem. reaction of p-nitrothiophenol (pNTP) dimerizing into p,p'-dimercaptoazobenzene (DMAB) has been monitored using single particle surface enhanced Raman spectroscopy, which provides laser wavelength- and power-dependent conversion rates of the reaction.
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56. 56
  Dai, Z. G.; Xiao, X. H.; Zhang, Y. P.; Ren, F.; Wu, W.; Zhang, S. F.; Zhou, J.; Mei, F.; Jiang, C. Z. In situ Raman scattering study on a controllable plasmon-driven surface catalysis reaction on Ag nanoparticle arrays. Nanotechnology 2012, 23 (33), 335701, DOI: 10.1088/0957-4484/23/33/335701
  [Crossref], [PubMed], [CAS], Google Scholar
  56
  In situ Raman scattering study on a controllable plasmon-driven surface catalysis reaction on Ag nanoparticle arrays
  Dai, Z. G.; Xiao, X. H.; Zhang, Y. P.; Ren, F.; Wu, W.; Zhang, S. F.; Zhou, J.; Mei, F.; Jiang, C. Z.
  Nanotechnology (2012), 23 (33), 335701/1-335701/6CODEN: NNOTER; ISSN:1361-6528. (Institute of Physics Publishing)
  Control of the plasmon-driven chem. reaction for the transformation of 4-nitrobenzenethiol to p,p'-dimercaptoazobenzene by Ag nanoparticle arrays was studied. The Ag nanoparticle arrays were fabricated by means of nanosphere lithog. By changing the PS particle size, the localized surface plasmon resonance (LSPR) peaks of the Ag nanoparticle arrays can be tailored from 460 to 560 nm. The controlled reaction process was monitored by in situ surface-enhanced Raman scattering. The reaction can be dramatically influenced by varying the duration of laser exposure, Ag nanoparticle size, laser power and laser excitation wavelength. The max. reaction speed was achieved when the LSPR wavelength of the Ag nanoparticle arrays matched the laser excitation wavelength. The exptl. results reveal that the strong LSPR can effectively drive the transfer of the "hot" electrons that decay from the plasmon to the reactants. The exptl. results were confirmed by theor. calcns.
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57. 57
  Walder, R.; Nelson, N.; Schwartz, D. K. Single molecule observations of desorption-mediated diffusion at the solid-liquid interface. Phys. Rev. Lett. 2011, 107 (15), 156102, DOI: 10.1103/PhysRevLett.107.156102
  [Crossref], Google Scholar
  There is no corresponding record for this reference.
58. 58
  Nelson, N.; Walder, R.; Schwartz, D. K. Single molecule dynamics on hydrophobic self-assembled monolayers. Langmuir 2012, 28 (33), 12108– 12113, DOI: 10.1021/la302369v
  [ACS Full Text ], [CAS], Google Scholar
  58
  Single Molecule Dynamics on Hydrophobic Self-Assembled Monolayers
  Nelson, Nathaniel; Walder, Robert; Schwartz, Daniel K.
  Langmuir (2012), 28 (33), 12108-12113CODEN: LANGD5; ISSN:0743-7463. (American Chemical Society)
  The interactions between adsorbate mols. and hydrophobic surfaces are of significant interest due to their importance in a variety of biol. and sepn. processes. However, it is challenging to extrapolate macroscopic ensemble-averaged force measurements to mol.-level phenomena. Using total internal reflection fluorescence microscopy to image individual mols. at hydrophobic solid-aq. interfaces, the authors directly obsd. dynamic behavior assocd. with the interactions between fluorescently labeled dodecanoic acid (the authors' probe mols.) and self-assembled monolayers (SAM) comprising n-alkyltriethoxysilanes with systematically increasing chain length (from n = 4-18). In all cases, the authors obsd. at least two characteristic surface residence times and two diffusive modes, suggesting the presence of multiple distinct adsorbed populations. In general, the mean surface residence time increased and the mobility decreased with increasing SAM chain length, consistent with stronger probe-surface interactions. However, these trends were not primarily due to changes in characteristic residence times or diffusion coeffs. assocd. with the individual populations but rather to a dramatic increase in the fraction assocd. with the long-lived slow-moving population(s) on long-chain SAMs. In particular, on longer (16-18 carbon) alkylsilane monolayers, the probe mol. exhibited far fewer desorption-mediated flights than on short (4-6 carbon) monolayers. Addnl., probes on the longer chain surfaces were much more likely to exhibit extended surface residence times as opposed to short transient surface visits.
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59. 59
  Pardo, L.; Boland, T. A quantitative approach to studying structures and orientation at self-assembled monolayer/fluid interfaces. J. Colloid Interface Sci. 2003, 257 (1), 116– 120, DOI: 10.1016/S0021-9797(02)00022-X
  [Crossref], Google Scholar
  There is no corresponding record for this reference.
60. 60
  Bishnoi, S. W.; Rozell, C. J.; Levin, C. S.; Gheith, M. K.; Johnson, B. R.; Johnson, D. H.; Halas, N. J. All-optical nanoscale pH meter. Nano Lett. 2006, 6 (8), 1687– 1692, DOI: 10.1021/nl060865w
  [ACS Full Text ], [CAS], Google Scholar
  60
  All-Optical Nanoscale pH Meter
  Bishnoi, Sandra W.; Rozell, Christopher J.; Levin, Carly S.; Gheith, Muhammed K.; Johnson, Bruce R.; Johnson, Don H.; Halas, Naomi J.
  Nano Letters (2006), 6 (8), 1687-1692CODEN: NALEFD; ISSN:1530-6984. (American Chemical Society)
  An Au nanoshell with a pH-sensitive mol. adsorbate functions as a standalone, all-optical nanoscale pH meter that monitors its local environment through the pH-dependent surface-enhanced Raman scattering (SERS) spectra of the adsorbate mols. Also, also the performance of such a functional nanodevice can be assessed quant. The complex spectral output is reduced to a simple device characteristic by application of a locally linear manifold approxn. algorithm. The av. accuracy of the nano-meter is ±0.10 pH units across its operating range.
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61. 61
  Benz, F.; Schmidt, M. K.; Dreismann, A.; Chikkaraddy, R.; Zhang, Y.; Demetriadou, A.; Carnegie, C.; Ohadi, H.; de Nijs, B.; Esteban, R.; Aizpurua, J.; Baumberg, J. J. Single-molecule optomechanics in “picocavities. Science 2016, 354 (6313), 726– 729, DOI: 10.1126/science.aah5243
  [Crossref], [PubMed], [CAS], Google Scholar
  61
  Single-molecule optomechanics in "picocavities"
  Benz, Felix; Schmidt, Mikolaj K.; Dreismann, Alexander; Chikkaraddy, Rohit; Zhang, Yao; Demetriadou, Angela; Carnegie, Cloudy; Ohadi, Hamid; de Nijs, Bart; Esteban, Ruben; Aizpurua, Javier; Baumberg, Jeremy J.
  Science (Washington, DC, United States) (2016), 354 (6313), 726-729CODEN: SCIEAS; ISSN:0036-8075. (American Association for the Advancement of Science)
  Trapping light with noble metal nanostructures overcomes the diffraction limit and can confine light to vols. typically ∼30 cubic nanometers. Individual at. features inside the gap of a plasmonic nanoassembly can localize light to vols. well <1 cubic nanometer (picocavities), enabling optical expts. on the at. scale. These at. features are dynamically formed and disassembled by laser irradn. Although unstable at room temp., picocavities can be stabilized at cryogenic temps., allowing single at. cavities to be probed for many minutes. Unlike traditional optomech. resonators, such extreme optical confinement yields a factor of 106 enhancement of optomech. coupling between the picocavity field and vibrations of individual mol. bonds. This work sets the basis for developing nanoscale nonlinear quantum optics on the single-mol. level.
  >> More from SciFinder ^®
  https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC28XhvVSnsLrP&md5=ccaa8fdd2c2c6561c678884f6a7557ea
62. 62
  Dufrêne, Y. F. Using nanotechniques to explore microbial surfaces. Nat. Rev. Microbiol. 2004, 2 (6), 451– 460, DOI: 10.1038/nrmicro905
  [Crossref], [PubMed], [CAS], Google Scholar
  62
  Using nanotechniques to explore microbial surfaces
  Dufrene, Yves F.
  Nature Reviews Microbiology (2004), 2 (6), 451-460CODEN: NRMACK; ISSN:1740-1526. (Nature Publishing Group)
  A review. The current understanding of microbial surfaces owes much to the development of electron microscopy techniques. Yet, a crucial limitation of electron microscopy is that it cannot be used to examine biol. structures directly in aq. solns. In recent years, however, at. force microscopy (AFM) has provided a range of new opportunities for viewing and manipulating microbial surfaces in their native environments. Examples of AFM-based analyses include visualizing conformational changes in single membrane proteins, the real-time observation of cell-surface dynamics, analyzing the unfolding of cell-surface proteins and detecting individual cell-surface receptors. These analyses have contributed to our understanding of the structure-function relationships of cell surfaces and will hopefully allow new applications to be developed for AFM in medicine and biotechnol.
  >> More from SciFinder ^®
  https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD2cXktVyisr4%253D&md5=c1f0fc9bfe4ea36e1fc4524952d551a8
63. 63
  Weaver, M. J.; Gao, X. In situ electrochemical surface science. Annu. Rev. Phys. Chem. 1993, 44 (1), 459– 494, DOI: 10.1146/annurev.pc.44.100193.002331
  [Crossref], Google Scholar
  There is no corresponding record for this reference.
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- Experimental details of the TERS system, sample preparation, and preparation of TERS probes including ZrO₂ coating; time series TERS measurements of unprotected Ag-coated TERS probes in air; time series TERS measurements of ZrO₂-protected Ag-coated TERS probes in air; AFM topography of the Ag substrate; comparison of the Raman spectrum of bulk pATP and SERS spectrum of pATP adsorbed on a heterogeneous Ag substrate; analysis of pATP → DMAB at the apex of the Ag-coated TERS probe in air; chemical inertness test of the ZrO₂-protected TERS probe; comparison of pATP → DMAB SERS spectra measured in air and water environments; comparison of far-field Raman spectra measured from a polystyrene thin film on glass in air and water; analysis of pATP → DMAB at the apex of the Ag-coated TERS probe in water; further analysis of the pATP → DMAB TERS map; and comparison of the first and last spectra measured in the TERS map (PDF)
- jz8b02496_si_001.pdf (1.86 MB)
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In Situ Nanoscale Investigation of Catalytic Reactions in the Liquid Phase Using Zirconia-Protected Tip-Enhanced Raman Spectroscopy Probes

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