ASAP (As Soon As Publishable)

Recycling waste salt in the dry reprocessing of nuclear fuel and reducing electric energy consumption in the electrorefining process are crucial steps toward addressing significant challenges in this field. The present study proposes a novel approach to purify waste salt by selectively adsorbing excessive fission products using 5A molecular sieves (5A), based on the principles of electrorefining, with the ultimate aim of achieving sustainable development in nuclear fuel. First, Lutetium (Lu)-Bi alloy was synthesized through constant potential electrolysis in the LiCl–KCl–LuCl₃ melt, resulting in a 90.59% extraction rate of Lu(III) on the Bi electrode. Subsequently, following the electrolysis process, the waste salt underwent high-temperature adsorption with a 5A for purification. The results of the experiment indicate that the utilization of 5A for adsorption can lead to a remarkable removal efficiency of Lu, reaching an impressive rate of 99.70%. Consequently, when combined with electrolytic reduction, the overall extraction rate of Lu is significantly enhanced to a remarkable 99.98%. Finally, experiments on the coexistence of rare earth elements were conducted, revealing a significant removal rate for Y, Ho, Tm, Yb, and Lu. This study presents innovative solutions for effectively utilizing waste salt in the nuclear fuel cycle.

Herein, we investigate the effects of ligand design on the nuclearity and reactivity of metal–ligand multiply bonded (MLMB) complexes to access an exclusively bimetallic reaction pathway for C–H bond functionalization. To this end, the diiron alkoxide [Fe₂(^PhDbf)₂] (1) was treated with 3,5-bis(trifluoromethyl)phenyl azide to access the diiron imido complex [Fe₂(^PhDbf)₂(μ-NC₈H₃F₆)] (2a) that promotes hydrogen atom abstraction (HAA) from a variety of C–H and O–H bond containing substrates. A diiron bis(amide) complex [Fe₂(^PhDbf)₂(μ-NHC₈H₃F₆)(NHC₈H₃F₆)] (3) was generated, prompting the isolation of the analogous bridging amide terminal alkoxide [Fe₂(^PhDbf)₂(μ-NHC₈H₃F₆)(OC₁₉H₁₅)] (4) and the asymmetric pyridine-bound diiron imido [Fe₂(^PhDbf)₂(μ-NC₈H₃F₆)(NC₅H₅)] (6a). We found that 6a is competent for toluene amination, indicating the effect of Lewis base-enhanced C–H bond functionalization. Mechanistic investigations suggest that the bimetallic bridging imido complex is the reactive intermediate as no monometallic species is detected during the time course of the reaction.

Replacing the sluggish anodic water oxidation reaction with the glucose oxidation reaction (GOR) offers an energy-saving strategy to obtain value-added products during the hydrogen production process. However, rational design of the GOR electrocatalyst with an explicit structure–property relationship remains a challenge. In this study, by using cobalt chalcogenides as model catalysts, we performed an in-depth study of the GOR catalytic mechanism of CoS and CoSe nanosheets. Experimental and theoretical results revealed that the reaction pathway on cobalt chalcogenides strongly depends on their binding energy to hydroxyl (OHBE). For CoS with a weak OHBE, the reaction proceeds through an “electrophilic oxygen” route. While for CoSe, due to the strong OHBE, a surface reconstruction occurs before the GOR and therefore follows the “electrochemical-chemical” route. Inspired by these findings, a customized strategy was proposed to regulate the OHBE of the catalysts, which involved introducing F atoms into CoS to enhance its OHBE, and weakening the OHBE of CoSe by doping with Zn atoms. The optimized F-doped CoS and Zn-doped CoSe catalysts both exhibited significantly improved performance for GOR. This study thus provides a verifiable paradigm for improving the GOR performance via a customized strategy and sheds light on the design of novel catalysts in the future.

The functional properties of tetraaryl compounds, M(aryl)₄ (M = transition metal or group 14 element), are dictated not only by their common tetrahedral geometry but also by their central atom. The identity of this atom may serve to modulate the reactivity, electrochemical, magnetic, and optical behavior of the molecular species, or of extended materials built from appropriate tetraaryl building blocks, but this has not yet been systematically evaluated. Toward this goal, here we probe the influence of Os(IV), C, and Si central atoms on the spectroelectrochemical properties of a series of redox-active tetra(ferrocenylaryl) complexes. We prepare these compounds through Negishi cross-coupling from brominated precursors and confirm, through single-crystal X-ray diffraction, they exhibit comparable molecular structures with only small differences attributable to their dissimilar M-aryl bond lengths. Solution voltammetric and spectroelectrochemical studies reveal that access to mixed-valence states is uniquely provided by the Os(IV) species, which also exhibits a near-IR absorption band that is characteristic of intervalence charge transfer processes. Together, this work serves to highlight the remarkable electrochemical stability and distinct electronic properties of the Os(aryl)₄ unit, as well as the potential utility of these and other M(aryl)₄ species as modular building blocks for three-dimensional polymers or functional molecular devices.

Three new analogues of Tb-UiO-66 with various functional groups (−F, −Br, −NH₂) on the terephthalic acid linker of the metal–organic framework (MOF) are synthesized and characterized. The photoluminescent properties of these analogues, as well as Tb-UiO-66 and Tb-UiO-66-(OH)₂, are studied and correlated to the calculated energies for the triplet (T₁) states of each linker. The results show that the addition of electron withdrawing groups, such as −F and −Br, lead to higher T₁ energies, resulting in quantum yields in the range of 6–31%. The addition of electron donating groups, on the other hand, lowers the T₁ energy of the organic linker and inhibits energy transfer such that emission is not observed.

Actinide elements are characterized by their unique electronic correlations, variable valence states, and localized 5f electrons, leading to unconventional electronic and topological properties in their compounds. The distinctive physical properties of actinide materials are maintained in low-dimensional forms, yet two-dimensional (2D) actinide materials remain largely unexplored due to their scarcity and the experimental challenges posed by their radioactivity. To fill the knowledge gap in 2D actinide materials, we theoretically designed a series of stable thorium-containing 2D materials, including MXenes, chalcogenides, halides, and other compounds with unique structures. These novel thorium-containing 2D materials show excellent thermodynamic, mechanical, and dynamical stability. Their electronic structures and potential applications were investigated. Considering the proper band edge positions, strong visible light absorption, and effective separation of photogenerated electron–hole pairs, ThPSe₃ is proposed as a promising photocatalyst for water splitting. Our work significantly expands the 2D actinide materials family, and further opens new avenues for their experimental realization and applications.

Reductive phosphatization is an original synthesis approach to the formation of transition metal phosphates (TMPs). The approach enables the synthesis of known TMPs, but also new compounds, especially with transition metals in a low-valent state. However, to exploit the enormous potential of this synthesis method, it is necessary to identify and characterize all of the potential intermediates and final synthesis products. Here, we report on in situ synchrotron X-ray powder diffraction experiments to unravel the temperature-dependent formation pathway of TMPs using TiO₂–NH₄H₂PO₂ as an example. The pathway consists of several consecutive steps, including the melting of NH₄H₂PO₂, which acts as a reducing agent and a reaction medium. A reduction in the ratio of TiO₂ to NH₄H₂PO₂ decelerates the reaction and causes increased impurity formation. The hypophosphite melt reduces Ti⁴⁺ in TiO₂ to Ti³⁺, and a previously unknown compound, denoted as Ti(III)po with chemical composition (NH₄)_xH_1–xTi(HPO₄)₂, is formed. In a subsequent step, (NH₄)_xH_1–xTi(HPO₄)₂ reacts in a polycondensation reaction to form monoclinic NH₄TiP₂O₇, denoted as Ti(III)p in our earlier work.

Electrochemical conversion of CO₂ into methanol has received extensive attention in recent years since methanol is an efficient energy carrier and industrial feedstock. However, the selectivity to methanol remains unsatisfied. In this work, Sb-doped Cs₃Cu₂I₅ is first and rationally developed for CO₂ electrochemical reduction, achieving remarkable high selectivity of methanol. UV–vis absorption, X-ray photoelectron spectroscopy (XPS), and density functional theory (DFT) calculations show that the Sb dopants narrow the band gap of Cs₃Cu₂I₅ and enhance the metal–ligand hybridization due to the introduction of Sb 5p orbitals, which accordingly enhance the charge transfer. In addition, the Cu–Sb pair in Sb@Cs₃Cu₂I₅ perovskite synergistically catalyzes the CO₂ conversion. The Cu sites serve for CO₂ absorption and activation, while the Sb sites stabilize the intermediate *OCH₂ through the Sb–O bond due to superior oxygen affinity. The plasma-treated sample with electron-deficient Sb exhibits the best methanol selectivity as high as 88.38%. This work provides new insight into highly efficient metal halide perovskite-based catalysts for CO₂ electrochemical conversion.

A series of 2-pyridone[α]-fused BOPHYs 6–8 were prepared via a two-step procedure involving the preparation of enamine, followed by an intramolecular heterocyclization reaction. In addition to being fully conjugated with the BOPHY core pyridone fragment, BOPHYs 7 and 8 have a pyridine group connected to the BOPHY core via one- or two –CH₂– groups. New BOPHYs were characterized by spectroscopy as well as X-ray diffraction. Conjugation of the pyridone fragment into the BOPHY core results in a significant red shift of the absorption and fluorescence while maintaining extremely high fluorescence quantum yields. Axial coordination and photophysical properties of the supramolecular dyads formed between pyridine-appended pyridone-fused BOPHYs 7 and 8 with TPP^F20Zn (TPP^F20Zn = zinc 5,10,15,20-tetrakis(pentafluorophenyl)porphyrin) were investigated using UV–vis and fluorescence spectroscopy and gave a binding constant in the range of 1.46 × 10⁵ to 4.6 × 10⁵ M^–1. The electronic structures and excited-state properties of new BOPHYs 6–8 and their donor–acceptor assemblies with TPP^F20Zn were studied by the density functional theory (DFT) and time-dependent DFT (TDDFT). The HOMO and HOMO – 1 of supramolecular complexes TPP^F20Zn-7/8 are TPP^F20Zn centered, while the LUMO is localized on the BOPHY entity, allowing potential HOMO → LUMO charge transfer from the TPP^F20Zn donor to the BOPHY acceptor.

Developing high-performance catalysts for the alcohol electrooxidation reaction is of significant importance for the practical application of direct fuel cells. Herein, a supported catalyst consisting of well-dispersive PdCu nanoparticles (NPs) and ultrathin NiZnP nanosheets (NSs) is synthesized. The high-surface-area NiZnP NSs provide a platform for good dispersion of PdCu NPs, resulting in stable catalysts with a large number of exposed surface atoms. Compared with PdCu NPs and commercial Pd/C, the metal–support interactions contribute to the activity and durability improvement of the PdCu/NiZnP nanohybrids. Moreover, the NiZnP NSs promote the formation of OH species, thereby facilitating the removal of carbonaceous intermediates and ensuring the long-term stability of PdCu/NiZnP nanohybrids. This study provides deep insight into the supported catalysts and a comprehensive understanding of the metal–support interactions, offering great opportunities for the design of efficient catalysts for direct fuel cells.

Copper-based halides have attracted significant attention due to their unique photophysical properties and diverse coordination configurations. However, enhancing water stability and modulating structural transitions in cuprous halide materials remain challenging. In this work, we successfully synthesized three copper(I) halides, (C₂₄H₂₈P)CuBr₂ (L1, [C₂₄H₂₈P]⁺ = hexyltriphenylphosphonium), (C₂₄H₂₈P)₂Cu₄Br₆ (L2), and (C₂₄H₂₈P)₂Cu₄I₆ (L3), via solvent volatilization, demonstrating exceptional water stability even after 27 days of submersion. Crystals L1 and L2 emit yellow and orange light, respectively, under ultraviolet excitation, while L3 emits green light when excited by blue light. A rapid phase transition between L1 and L2 occurs when stimulated with methanol at room temperature. Further exposure of L2 to a NaI solution can result in substitution of Br^– ions by I^– in [Cu₄Br₆]^2– to form L3. Multimodal anticounterfeiting luminescent labels with high-security levels have been successfully manufactured based on sequential L1 → L2 → L3 phase transition. Moreover, a test paper designed based on L1 can be applied for low-level methanol detection. This work successfully accomplishes the coregulation of structural transformations and luminescence switching in copper(I) halides by combining methanol simulations with halogen substitution strategies, which not only deepens the understanding of the structure–property relationships but also broadens the optical applications of these materials.

We present two novel antimony(III)-based tellurite sulfate crystals, Sb₂(TeO₃)(SO₄)₂-P1̅ (I) and Sb₂(TeO₃)(SO₄)₂-P2₁/c (II), synthesized using a dual lone pair strategy that incorporates Sb³⁺ and Te⁴⁺ ions into a sulfate framework. This approach significantly enhances the birefringence of these compounds, with values of 0.11 and 0.10 at 546 nm, respectively, surpassing those of many previously reported mixed alkali metal/alkaline earth metal sulfates and tellurites. Both compounds also exhibit excellent UV transparency with cutoff edges at 292 and 294 nm, making them promising candidates for short-wave UV optical applications. Structural and theoretical analyses reveal that the enhanced birefringence arises from the synergistic effects of the stereochemically active lone pairs of Sb³⁺ and Te⁴⁺, which contribute to the optical anisotropy. This work highlights the potential of dual SCALP elements in improving the optical properties of sulfate-based crystals and provides new insights into designing high-performance optical materials with tailored properties for advanced UV technologies.

Ionic liquids were used as low temperature solvents for the synthesis of new lanthanide and transuranic-element (TRU) borate cluster structures. Ionothermal synthesis with the ionic liquid [BMIm]Cl (1-butyl-3-methylimidazolium chloride) yielded the La, Nd, and Am containing phases La₄B₂₂O₄₂Cl₁₂, Nd₄B₂₂O₄₂Cl₁₂, and Am₄B₂₂O₄₂Cl₁₂. The structures of the La, Nd, and Am borate clusters were determined by single crystal X-ray diffraction (SCXRD) and found to be cubic, in the chiral space group I23. Solid state NMR and Raman spectra confirm the structure descriptions. This represents the first ionothermal synthesis of an americium containing cluster compound, and the study of such low-temperature methods benefit work on TRU materials.

It is especially essential to develop high-performance and low-cost nonprecious metal catalysts for large-scale hydrogen production. A large number of electrochemical catalysts composited by transition metal centers has been reported; however, it is still a great challenge to design and manipulate target electrocatalysts to realize high overall water-splitting activity at the atomic level. Herein, we develop totally new P-(Fe,V)-codoped metastable-phase β-NiMoO₄. As an electrocatalyst, it can realize oxygen evolution at only 163 mV and hydrogen evolution at only 44 mV at 10 mA cm^–2. It, as both an anode and a cathode, is fabricated into a cell for overall water splitting, which has an ultralow voltage value of 1.48 V to drive a current density of 10 mA cm^–2 and can remain stable for at least 100 h. In the target electrode, the P element plays three important roles: (1) it can stabilize the metastable-phase structure of β-NiMoO₄; (2) it can further optimize the electronic structure; and (3) it can provide more active sites. The synergistic effect for multimetal centers with different redox couples is key for the great improvement of catalytic activity. The related mechanism is discussed in detail.

The diaspore-type crystalline structure is historically well-known in mineralogy, but it has also been widely studied for various applications in the field of catalysis, electrocatalysis, and batteries. However, once two anions of similar ionic size but different electronegativity, such as F^– and O^2– or more precisely OH^–, are combined, the knowledge of the location of these two anions is of paramount importance to understand the chemical properties in relation with the generation of hydrogen bonds. Coprecipitation and hydrothermal routes were used to prepare hydroxide-fluorides that crystallize all in an orthorhombic structure with four formula units per cell. By coupling X-ray scattering techniques for both long- and short-range order (XRD and PDF) and by using multiple complementary spectroscopic probes (Raman, FTIR, and 1D/2D ¹⁹F and ¹H MAS NMR measurements), preferential anionic site occupancy by hydroxyl groups and fluoride ions is demonstrated. Moreover, in the Mg(OH)F diaspore network, 10% of Mg²⁺ is located in the tunnels, resulting in cationic vacancies in the main site. The preference for OH at the edges is clearly marked in the case of Mg(OH)F, whereas OH is preferred at the vertices in Zn(OH)F, regardless of the allotropic form. The dominant polar low-symmetry Pna2₁ form of Zn(OH)F has more OH groups at the vertices than the parent centrosymmetric Pnma variety, in agreement with its strongest hydrogen bonds. Given the remarkable flexibility of the diaspore-type network, the thermal stability of these hydroxide-fluorides is perfectly matched to the structural characteristics. The location of anionic groups within the diaspore framework should play a key role in understanding and optimizing physicochemical properties such as proton mobility for alkaline batteries and acid–base properties for heterogeneous catalysis.

Building upon an earlier study of heme-nitrosyl complexes (Inorg. Chem. 2023, 62, 20496–20505), we examined a wide range of nonheme {FeNO}^6–10 complexes (the superscript represents the Enemark-Feltham count) and two dinitrosyl iron complexes using DMRG-CASSCF calculations. Analysis of the wave functions in terms of resonance forms with different [π*(NO)]ⁱ occupancies (where i = 0–4 for mononitrosyl complexes) identified the dominant electronic configurations of {FeNO}⁶ and {FeNO}⁷ complexes as Fe^III–NO⁰ and Fe^II–NO⁰, respectively, mirroring our previous findings on heme-nitrosyl complexes. A trigonal-bipyramidal S = 1 {FeNO}⁸ complex with an equatorial triscarbene ligand set appears best described as a resonance hybrid of Fe^I–NO⁰ and Fe^II–NO^–. Reduction to the corresponding S = 1/2 {FeNO}⁹ state was found to involve both the metal and the NO, leading to an essentially Fe^I–NO^– complex. Further reduction to the {FeNO}¹⁰ state was found to be primarily metal-centered, leading to a predominantly Fe⁰–NO^– configuration. Based on the weights w_i of the [π*(NO)]ⁱ resonance forms, an overall DMRG-CASSCF-based π*(NO) occupation number could be derived, which was found to exhibit a linear correlation with both the NO bond distance and NO stretching frequency, allowing a readout of the NO oxidation state from the NO bond distance.

Layered sulfide crystals are suitable hosts for lithium and sodium ions in batteries. In this study, new layered lithium titanium sulfide (LTS) crystals were grown in a sealed silica tube using a Li₂S self-flux at 800–950 °C. X-ray diffraction (XRD) analysis results indicated the formation of a new sulfide phase with higher symmetry in the Li–Ti–S system. The chemical compositions of the resulting crystals were estimated to be Li_1.8TiS_2.7 from elemental analysis, and indexing the XRD pattern of LTS afforded lattice constants and the monoclinic space group C2/m (no. 12). Based on these results, an initial structural model of LTS was constructed and verified using Rietveld refinement. The characterization results indicated that the grown LTS crystals had a layered structure with lithium and silicon deficiencies in Li₂TiS₃. The use of Li₂S self-flux at 950 °C enabled the effective growth of LTS crystals with sizes of 10–20 μm. Electrochemical measurements confirmed the Li⁺ insertion-extraction characteristics of the LTS crystals.

The incorporation of a selenoimidazolium-based chalcogen bond (ChB) donor into a bis-heteroleptic Ru(II) complex (Ru–Se) has been designed for the first time to explore its anion-sensing properties and understand its selectivity to specific classes of anions. Photophysical studies demonstrate the receptor’s selectivity toward phosphates, while ¹H NMR displays its ability to recognize both I^– and H₂PO₄^– among the different halides and oxoanions through ChB interaction in CH₃CN and dimethyl sulfoxide-d₆ solvents, respectively. Additionally, microscopic studies such as DLS and TEM reveal that the selective turn-on sensing of H₂PO₄^– and HP₂O₇^3– compared to I^– is driven by supramolecular aggregation behavior. Hence, the successful fabrication of a selenium ChB-based Ru(II) complex makes it a promising candidate for anion monitoring in supramolecular chemistry.

Extracting uranium from nuclear wastewater is vital for environmental and human health protection. However, despite progress in uranium extraction, there remains a demand for an optimized adsorbent with improved capability, efficiency, and selectivity. To bridge this gap, 1,2,3,4-butane tetracarboxylic acid (BTCA)-modified MIL-101 was synthesized through a simple hydrothermal reaction between amino-modified MIL-101 (MIL-101-NH₂) and BTCA. Density Functional Theory calculations validated the formation of stable coordination bonds and a hydrogen bond network, bolstering the adsorption capacity. To further enhance this capacity, the influence of an electric field on adsorption performance was investigated. Studies revealed that uranyl ion removal under an electric field involves both electrosorption and electroreduction pathways. This dual mechanism not only significantly increases the adsorption capacity from 221.1 mg g^–1 to 331.4 mg g^–1 but also improves the adsorption efficiency. These insights not only enhance our understanding of effective uranium removal but also foster the development of sustainable, ecofriendly technologies in the nuclear energy field.

Mn²⁺-doped luminescent materials play a significant role in a variety of fields, including modern lighting, displays, and imaging. Mn²⁺ exhibits a broad and adjustable emission, hinging on the local environment of the crystal field and the interaction of the 3d⁵ electrons. However, it is still a challenge to realize the precise control of the emission of Mn²⁺ ions due to site-prior occupation in a specific lattice. Here, the formation of Mn–Mn dimers is proposed to be an effective strategy to design a novel red emission. Multimode emitters in Mn²⁺-activated AZn₄(PO₄)₃ (A = K, Rb, and Cs) with unique [Zn₄PO₁₂] chains and [ZnO_n] groups are observed to achieve regular green and unusual red emissions. KZn₄(PO₄)₃:Mn²⁺ shows broad dual emissions at 542 and 608 nm, attributed to [MnO₄] and [Mn₂O₇] dimers, respectively. While K is replaced with Rb and Cs, the Zn ions form [ZnO₄] tetrahedra and [ZnO₅] octahedra. RbZn₄(PO₄)₃:Mn²⁺ exhibits a broad red emission at 618 nm, ascribing to [Mn₂O₇] and [Mn₂O₈] dimers. CsZn₄(PO₄)₃:Mn²⁺ also displays a broad orange-red emission at 608–620 nm with increasing doping levels, deriving from energy transfer from [MnO₅] to [Mn₂O₇] and [Mn₂O₈] dimers. This work provides a framework for creating novel red emissions from Mn²⁺-doped luminescent materials.

The performance of energetic coordination compounds (ECCs) is influenced by their components and structure. Modifying the chemical structure of the ligands can balance the detonation performance and sensitivity. This study introduced Cu(3-PZCA)₂(ClO₄)₂ (ECCs-1) and Cu(2-IZCA)₂(ClO₄)₂ (ECCs-2), using 3-PZCA and 2-IZCA as ligands. ECCs-2, with a higher symmetry and fewer nitrogen chains, showed the highest thermal decomposition temperature (225 °C). Both ECCs displayed high mechanical sensitivity, with ECCs-2 being slightly less sensitive (IS = 3 J, FS = 8 N). They shared similar detonation properties and ignition capabilities, with ECCs-1 having the highest detonation velocity (7.1 km·s-1) and pressure (23.5 GPa). Initiation tests confirmed their excellent performance and similar DDT. The theoretical decomposition mechanism suggests a free radical reaction, explaining their consistent mechanical sensitivity, ignition, and initiation capabilities. A “SP–DM–DSC–MS–DA” structure–property relationship was established, providing a theoretical foundation for studying Cu(ClO₄)₂-ECCs and their isomers.

Promoting the rate of the oxygen reduction reaction (ORR) is critical for boosting the overall energy efficiency of the flexible zinc–air batteries (FZABs). Inspired by nature, we designed “branch-leaf” like hierarchical porous carbon nanofibers with ultralow loadings of Ir nanoparticles (NPs) derived from covalent–organic framework/metal–organic framework (COF/MOF) core–shell hybrids. The as-obtained Ir/FeZn-hierarchical porous carbon nanofibers (HPCNFs) showcase enhanced ORR performance, and the ultralow Ir loading reduces the cost while maintaining catalytic capacity. Interestingly, the FZABs assembled with Ir/FeZn-HPCNFs deliver an impressive stable performance. This work provides a feasible approach for designing cost-effective and highly efficient electrocatalysts using in FZABs.

Upcycling organic and inorganic waste into value-added metal–organic frameworks (MOFs) presents a sustainable strategy for mitigating waste pollution and promoting economic viability. However, rapid synthesis of MOF materials derived from actual industrial waste under mild conditions remains challenging. Herein, Fe-MOF MIL-88B(Fe) was successfully fabricated within 1 h at room temperature using galvanizing pickling waste liquid and terephthalic acid derived from waste poly(ethylene terephthalate). The resulting Fe-MOF (s-MIL-88B(Fe)) was employed to activate peroxymonosulfate (PMS) under UV light irradiation, achieving over 87% degradation of tetracycline hydrochloride (TCH) within 15 min. The effects of the reaction parameters on TCH degradation were thoroughly investigated. s-MIL-88B(Fe) demonstrated good stability and reusability, maintaining 96% of the initial activity after five cycles. The system also demonstrated adaptability to various organic pollutants and water matrices. Radicals (SO₄^–•) and nonradicals (¹O₂, h⁺) identified as the key reactive species promoted TCH degradation. The formation mechanism of reactive species and the degradation pathway of TCH are proposed. Toxicity evaluation verified the reduced toxicity after the degradation. This work provides a sustainable approach to upcycling industrial waste into MOF-based materials for efficient environmental remediation under mild conditions.

The platelike nickel-terephthalate-type metal–organic framework nanoarrays (Ni-BDC NAs) on carbon cloth are obtained by employing agaric-like Ni(OH)₂ NAs as sacrificial templates. The microenvironment of Ni-BDC NAs is modulated by various neighboring functional groups (−NH₂, −NO₂, and −Br) on the carboxylate ligand, exerting minimal destructive effects on the structure and morphology of Ni-BDC NAs. The electrochemical oxygen evolution reaction (OER) of Ni-BDC–NH₂ NAs, Ni-BDC–NO₂ NAs, and Ni-BDC–Br NAs exhibited a significant enhancement compared to that of Ni-BDC NAs alone, as evidenced by both experimental and theoretical assessments. The presence of neighboring groups exerts a positive influence on the electronic coupling between Ni and O atoms, thereby facilitating the thermodynamically favorable formation of *O intermediates on Ni sites and accelerating the kinetics of the OER. The findings presented here provide valuable insights for the design and utilization of carboxylic acid molecules with functional group effects, enhancing the activity of the OER across diverse Ni centers.

The development of robust and effective photoanodes is crucial for photoelectrochemical hydrogen production via total water splitting. Herein, the Ta₂O₅/α-Fe₂O₃/Co–Ni PBA (TFPB-1) photoanode was constructed by the compositing n-type Ta₂O₅ and n-type α-Fe₂O₃ followed by the deposition of p-type Co–Ni PBA. The IPCE of TFPB-1 was increased to 35.4% compared to 13.9% for Ta₂O₅ owing to the significantly improved light absorption efficiency, carrier separation efficiency and injection efficiency. The TFPB-1 achieved a current density of 2.78 mA cm^–2 at 1.23 V (vs RHE), which was around 18.5 times that of Ta₂O₅. The OER overpotential over TFPB-1 was reduced to 0.59 V compared to 1.13 V for Ta₂O₅, resulting in a substantial reduction in the free energy of PEC water oxidation over TFPB-1. As a result, TFPB-1 exhibited remarkably enhanced photoelectrocatalytic activity for oxygen evolution through water oxidation.

As promising optoelectronic functional materials in the short-wavelength spectral region, such as ultraviolet (UV) and deep UV, phosphates have recently received increased attention. However, phosphate materials commonly suffer from limited birefringence owing to the highly symmetrical PO₄ tetrahedra. We herein report a layered tin(II) phosphate with improved birefringence. By employing a polarizing microscope, the measured refractive index difference determined on a (010) wafer is 0.042@550 nm, which is very close to the calculated refractive index difference of 0.039@550 nm between n_x and n_z through the density functional theory (DFT) method. The largest birefringence appears on the (100) plane, which is theoretically determined to be 0.078@550 nm. Single crystals of SnHPO₄ measuring 20 × 4 × 3 mm³ can be easily grown by a hydrothermal method. In addition, SnHPO₄ is UV transparent with a short UV absorption cutoff edge of 242 nm and an optical band gap of 4.50 eV, implying that it could be a potential UV birefringent material.

The development of photoresponsive ferroelastics, which couple light-induced macroscopic mechanical and microscopic domain properties, represents a frontier in materials science with profound implications for advanced functional applications. In this study, we report the rational design and synthesis of two new organic–inorganic hybrid ferroelastic crystals, (MA)(Me₄N)[Fe(CN)₅(NO)] (MA = methylammonium) (1) and (MA)(Me₃NOH)[Fe(CN)₅(NO)] (2), using a dual-organic molecular design strategy that exploits hydrogen-bonding interactions for tailoring ferroelastic properties. Specifically, 1 exhibits a two-step phase transition at 138 and 242 K, while the introduction of a hydroxyl group in 2 stabilizes its ferroelastic phase to a significantly higher temperature, achieving a phase transition at 328 K, 86 K above that of 1. This enhancement is attributed to hydrogen bonding between the hydroxyl group of Me₃NOH⁺ and the nitroprusside anion, which suppresses lattice dynamics and reinforces structural stability. Remarkably, 2 demonstrates a large spontaneous strain of 0.153, vastly exceeding the 0.021 of 1, and undergoes an 11% size change along the b-axis in response to thermal stimuli. Both compounds exhibit reversible, photoinduced nitrosyl-linkage isomerization, as confirmed by IR spectroscopy, transitioning between the ground state (N-bound nitrosyl) and the metastable state (O-bound nitrosyl). This integration of photoresponsive functionality with ferroelastic properties establishes a versatile platform for energy-efficient actuation, adaptive devices, and multifunctional sensing applications. These findings offer an innovative pathway for designing next-generation hybrid materials with enhanced tunable properties.

Symmetrical bis(hydrazone)-based ligands, H₄dar(bhz)₂ (I), H₄dar(fah)₂ (II), H₄dar(nah)₂ (III), and H₄dar(inh)₂ (IV) obtained from 4,6-diacetylresorcinol (H₂dar) and different hydrazides [benzoylhydrazide (Hbhz), isonicotinoylhydrazide (Hinh), nicotinoylhydrazide (Hnah), and 2-furoylhydrazide (Hfah)], were used to prepare potassium salts of binuclear cis-[V^VO₂]⁺ complexes, {K(H₂O)₂}₂[(V^VO₂)₂dar(bhz)₂] (1), {K(H₂O)₂}₂[(V^VO₂)₂dar(fah)₂] (2), {K(H₂O)₂}₂[(V^VO₂)₂dar(nah)₂] (3), and {K(H₂O)₂}₂[(V^VO₂)₂dar(inh)₂] (4), and binuclear [V^IVO]²⁺ complexes, [{V^IVO(MeOH)}₂dar(bhz)₂] (5), [{V^IVO(MeOH)}₂dar(fah)₂] (6), [{V^IVO(MeOH)}₂dar(nah)₂] (7), and [{V^IVO(MeOH)}₂dar(inh)₂] (8). In the presence of warm MeOH/DMSO (4:1), 3 changed to {K(H₂O)₂}[(V^VO₂)₂Hdar(nah)₂]·DMSO (3a·DMSO). Single crystal XRD studies of 1 and 3a confirm a binuclear structure along with a distorted square pyramidal geometry of each vanadium center where bis{ONO(2−)} ligands coordinate through phenolate-O, azomethine-N, and enolate-O atoms of each unit. While growing crystals of 6 in EtOH, part of it oxidizes and gives [{V^VO(OEt)}₂dar(fah)₂] (9) along with powdery 6. Complex 9 has a distorted octahedral structure. These complexes were used as catalysts for the synthesis of biologically important 2-phenylquinazolin-4-(3H)-ones having different aryl aldehydes, and they all show excellent catalytic performance (up to 97% yield) in less reaction time and low temperature, in the presence of 70% aqueous TBHP/30% aqueous H₂O₂ as a greener oxidant. Generally, these complexes perform better than their mononuclear analogues. Spectroscopy, DFT studies, and isolated intermediates have helped in proposing a suitable reaction mechanism for the catalytic reaction.

Three new hexagonal perovskites with Cs₃M⁺M²⁺RhCl₉ (M⁺ = Na⁺, Ag⁺; M²⁺ = Mn²⁺, Fe²⁺) stoichiometry have been synthesized from solution precipitation reactions. These air-stable compounds crystallize as triply cation-ordered variants of the 6H perovskite structure. This structure contains octahedra that share a common face to form M²⁺RhCl₉^4– dimers that are arranged on a two-dimensional triangular network. M⁺ cations reside in octahedral holes located between dimer layers and connect M²⁺RhCl₉^4– dimers through corner-sharing linkages. The cation sites in the corner-sharing layers are fully occupied by Na⁺/Ag⁺, except for Cs₃AgMnRhCl₉, where a small amount of Ag⁺/Mn²⁺ antisite disorder is observed. The M²⁺RhCl₉^4– dimers adopt an ordered configuration that lowers the symmetry from P6₃/mmc to P6₃mc. Optical absorption in the near ultraviolet (UV) and visible regions is dominated by Rh d-to-d transitions and metal-to-metal charge transfer transitions. Variable temperature magnetic susceptibility measurements show no sign of long-range magnetic order down to 2 K. Curie–Weiss fits reveal relatively weak antiferromagnetic interactions between M²⁺ ions, with Weiss constants that range from −2.3 to −5.4 K. The strength of the antiferromagnetic interactions between M²⁺ ions increases as the covalency of the M²⁺–Cl bond increases. The ordering of three different cations in the 6H perovskite structure diminishes magnetic coupling between layers, leading to a new family of two-dimensional triangular lattice antiferromagnets.

The ability to finely tune the nuclearity of active metal sites is critical for designing highly selective catalysts, especially for hydrogenation processes. In this work, we developed a novel PdCu catalyst with an ordered body-centered cubic (BCC) structure, enabling precise control over Pd nuclearity to optimize selectivity. Using a facile polyol synthesis method, we modulated the Pd coordination environment, reducing the Pd–Pd coordination number from 3 (disordered face-centered cubic, FCC) to 0 (ordered BCC), thereby achieving full isolation of Pd by the surrounding Cu atoms. This structural transformation enhances hydrogen spillover and weakens ethylene adsorption, resulting in superior activity for the selective hydrogenation of acetylene to ethylene. The ordered PdCu supported on Al₂O₃ (o-PdCu/Al₂O₃) achieved a 99% acetylene conversion with an 84.5% ethylene selectivity at near-room temperature. This work highlights the importance of controlling atomic-scale nuclearity in metal catalysts and provides a promising strategy for improving the catalytic efficiency and selectivity in industrially significant processes.

Previous studies on natural samples of pampaloite (AuSbTe) revealed the crystal structure of a potentially cleavable and/or exfoliable material, while studies on natural and synthetic montbrayite (Sb-containing Au₂Te₃) claimed various chemical compositions for this low-symmetry compound. Few investigations of synthetic samples have been reported for both materials, leaving much of their chemical, thermal, and electronic characteristics unknown. Here, we investigate the stability, electronic properties, and synthesis of the gold antimony tellurides AuSbTe and Au_1.9Sb_0.46Te_2.64 (montbrayite). Differential thermal analysis and in situ powder X-ray diffraction revealed that AuSbTe is incongruently melting, while Au_1.9Sb_0.46Te_2.64 is congruently melting. Calculations of the band structures and four-point resistivity measurements showed that AuSbTe is a semiconductor and Au_1.9Sb_0.46Te_2.64 a metal. Various synthesis attempts confirmed the limited stable chemical composition of Au_1.9Sb_0.46Te_2.64, identified successful methods to synthesize both compounds, and highlighted the challenges associated with single-crystal synthesis of AuSbTe.

N-heterocyclic carbene (NHC)-based phosphorescent iridium complexes have attracted extensive attention due to their good optical properties and high stability in recent years. However, currently reported NHC-based iridium complexes can easily achieve emission of blue, green, or even ultraviolet light, while emission of red or deep-red light is relatively rare. Here, we report a new family of NHC-based deep-red iridium complexes (Ir1, Ir2, Ir3, and Ir4) featuring three-charge (0, −1, −2) ligands. The single-crystal structures confirm that all complexes exhibit a trans-C–N configuration between the NHC carbon atom of the monoanionic (−1) ligand and the nitrogen atom of the neutral (0) ligand and that there are abundant intermolecular and intramolecular interactions in the crystalline state. Notably, all complexes exhibited an effective deep-red emission (650–664 nm). Moreover, the iridium complexes (Ir2 and Ir4) based on benzimidazol-2-ylidene (pmb) exhibited a higher emission efficiency and longer emission lifetime than the corresponding iridium complexes (Ir1 and Ir2) based on imidazol-2-ylidene (pmi), respectively. Density functional theory calculations demonstrate that the pmb ligand of Ir3 and Ir4 is more involved in the excited state than the pmi ligand of Ir1 and Ir2, which is caused by the stronger electron-donating ability of the pmb ligand. Considering better optical properties, Ir2 and Ir4 were eventually used as dopant emitters of the optical light-emitting diode (OLED) devices to obtain good maximum external quantum efficiency (8.5 and 10.1%) in the deep-red region (628 and 624 nm) with Commission Internationale deL’Eclairage (CIE) coordinates of (0.65, 0.34) and (0.63, 0.36), respectively, with a low turn-on voltage (2.4 V). This research provides an important idea for the design and optoelectronic applications of NHC-based deep-red phosphorescent iridium complexes.

Luminescent lanthanide compounds stand out for their distinctive characteristics including narrow emission bands, substantial Stokes shifts, high quantum yields, and unique luminescent colors. However, Ln³⁺ is highly susceptible to vibrational quenching from X–H (X = O/N) high-energy oscillators in the embedded organic antenna, resulting in significant nonradiative energy dissipation of the ⁵D excited states of Ln³⁺. Herein, we introduce a strategy based on supramolecular interactions to modulate the nonradiative transitions in a new Zn^II–Tb^III heterometallic compound, [ZnTb(HL)₂(NO₃)Cl₂]·2CH₃CN·H₂O (ZnTb), based on a phenyl-substituted pyrazolinone-modified salicylamide-imide ligand (H₂L). The regulation mechanisms are explored in detail both experimentally and theoretically. With the N,N′-dimethylformamide (DMF)-boosted Tb³⁺ luminescence, ZnTb⊃DMF (1 mg of ZnTb + 2 mL of DMF) realizes a rapid (3s) and sensitive detection of water in DMF with a detection limit of 0.021%. Further, ZnTb⊃DMF can detect trace amounts of water in ethanol and ethanol gasoline with a low detection limit of 0.023% and 0.048%. In addition, portable paper strips of ZnTb⊃DMF are prepared to improve its practicability, which can afford real-time and faster (1 s) in situ visual sensing of trace amounts of water in common organic solvents and ethanol gasoline with sensitivity comparable to the titration results. This study provides a new idea for the lanthanide luminescence modulation and application in the field of fluorescence sensing.

Defining the active sites and further optimizing their activity are of great significance for enhancing the hydrogen evolution reaction (HER) performances, especially for inexpensive Ni-based catalysts doped with metals and nonmetal elements. This work reports the role of the incorporated molybdenum and sulfur in enhancing the HER activity of nickel. The prepared molybdenum and sulfur coincorporated Ni (NMS) electrocatalysts exhibit excellent HER performance, with an overpotential and Tafel slope of 77.0 mV (10 mA·cm^–2) and 64.4 mV·dec^–1, respectively, because of the large electrochemically active surface area, quick reaction kinetics, and charge-transfer capability. The theoretical calculation results reveal that the incorporated Mo atoms play the role of reaction sites, and the introduced S atoms can further enhance the activity of Mo atom. The high HER activity of the Mo atom can be attributed to the regulated d-band center by optimizing the composition of NMS, which tunes the interaction between Mo and intermediate species. The elucidated mechanism can make it possible to design Ni-based electrocatalysts doped with metals and nonmetals for efficient hydrogen evolution.

The present study details the synthesis and characterization of a robust, monomeric Al–H aluminate supported by a tridentate tris-phenolate ligand, isolated as [2][Li(THF)₄] and [2][N(ⁿBu)₄] salts, which were then exploited as CO₂ hydroboration catalysts. As initial reactivity studies, it was observed that the nucleophilic Al–H anion in [2][C] (C = countercation [Li(THF)₄]⁺ or [N(ⁿBu)₄]⁺) reacts fast with CO₂, to afford the corresponding Al-formate complexes [3][C], which were isolated and structurally characterized. Such anions were then exploited as potential CO₂ reduction catalysts. Salts [2–3][N(ⁿBu)₄] are efficient and robust CO₂ hydroboration catalysts in the presence of pinBH or Me₂S-BH₃ as hydroborane sources to selectively afford formate-equivalent or methanol-equivalent products (TON up 1920), depending on reaction conditions and the nature of the countercation. As deduced from detailed DFT calculations, the Al-formate anion [3]⁻ acts as a nucleophilic catalyst (for borane activation) but also as an electrophile (through the AlOCO carbon) allowing CO₂ activation/functionalization and thus the reduction catalysis to occur, a process thermodynamically driven by the stability of the reduction products. The anionic nature of [2]⁻ and [3]⁻ aluminates, resulting in an enhanced nucleophilicity (vs neutral analogues), may thus be crucial for catalytic activity. In contrast, according to DFT calculations performed with a model anion of [3]⁻ and pinBH, a CO₂ reduction processing via an Al–O/B–H σ-bond metathesis appears to be kinetically unfavored. The proposed mechanism involving an electrophilic/nucleophilic dual-activation mode also rationalizes the importance of countercation [C]⁺ in [2-3][C] for catalytic activity and selectivity, as demonstrated by the higher performance of [2][N(ⁿBu)₄] vs [2][Li(THF)₄].

The electrocatalytic 5-hydroxymethylfurfural (HMF) oxidation reaction (HMFOR) toward 2,5-furandicarboxylic acid (FDCA) has been considered a promising approach for the substitution of the energy-consuming and hazardous oxygen evolution reaction and for the valorization of renewable biomass. However, it is limited by the susceptibility of HMF to the oxidative environment and requires efficient electrocatalysts. Herein, a NiMo complex (NiMo–N) is provided as the precatalyst for the HMFOR, exhibiting favorable performances with a current density of 450 mA·cm^–2 achieved at an anodic potential of 1.4 V vs RHE (similarly hereinafter) with 50 mmol/L (mM) HMF and over 95% HMF conversion and FDCA FE for at least five cycles. Combined with quasi situ and in situ analysis, it is confirmed that the extensive lattice distortions in the precatalyst facilitate the in-depth reconstruction, increasing the accessible Ni sites and defective oxygen vacancies (O_v), which would promptly convert to high-valence Ni and active O species during the reaction. The improved performance is then attributed to the incorporation of the improved chemisorption and dehydrogenation ability of HMF by the as-evolved active sites.

A series of compositions NiIn_1–xSn_x (x = 0–1) were synthesized by conventional high-temperature synthesis, and as-synthesized samples were checked by powder X-ray diffraction experiments. NiIn_1–xSn_x (x < 0.7) mainly forms the ternary variant of the CoSn-type structure (P6/mmm), whereas, x = 0.7–0.9, NiIn_1–xSn_x forms predominantly an orthorhombic (Pnma) phase. To resolve the accurate crystal structure of hexagonal NiIn_1–xSn_x, a combination of single-crystal X-ray diffraction and neutron powder diffraction techniques is employed. It is revealed that in the crystal structure of NiIn_1–xSn_x (x < 0.7), the Sn gradually substitutes one of the two In sites present in the NiIn (CoSn-type) and forms the pseudobinary NiIn_1–xSn_x (x < 0.7). These experimental findings on the specific site substitution are supplemented by first-principles density functional theory (DFT) calculations. Mulliken’s and Löwdin’s population and Bader charge analyses further support the unexpected substitution of Sn for one In site in the structure of hexagonal NiIn_1–xSn_x. The structure can be viewed as an alternating arrangement of two flat atomic layers in the [001]: Kagomé layer of Ni atoms with indium at the center of the hexagons and honeycomb nets of In/Sn. Density of state (DOS) calculations, crystal orbital Hamilton population (COHP) calculations, and crystal orbital bond index (COBI) calculations further elucidate the stability and bonding scenario in the hexagonal phases. Interestingly, gradual Sn inclusion into the CoSn-type NiIn downshifts the 3d band center from the Fermi level that could influence the catalytic performance as well as many intriguing properties. These findings not only contribute to the fundamental understanding of atomic ordering between neighboring elements in NiIn_1–xSn_x but also pave the way for designing fascinating physical and chemical properties.

Utilization of carbon dioxide (CO₂) as a C1 feedstock to synthesize value-added chemicals using a catalyst made from earth-abundant elements and under mild conditions is a sustainable approach toward carbon neutrality but difficult to achieve. Herein, the CoAl₂O₄/Al₂O₃ composite catalyst is developed and used for the light-driven epoxide to value-added cyclic carbonate conversion using CO₂. CoAl₂O₄/Al₂O₃ composite catalysts (x% Co–Al₂O₃) are prepared by calcining cobalt-incorporated Al-oxy-hydroxide at 500 °C under an air atmosphere. The composite 15% Co–Al₂O₃ (57% Al₂O₃ and 43% CoAl₂O₄) shows the highest photothermal conversion efficiency (η = 66%) as well as catalytic activity toward CO₂ fixation into epoxides to generate cyclic carbonates under 1 atm CO₂ pressure and solvent-free conditions (300 W xenon lamp). The catalyst displays good selectivity for the synthesis of a series of cyclic carbonates (>95%) with good yield in the presence of tetra butyl ammonium iodide (TBAI) as a cocatalyst (2 mol % with respect to epoxide). Under the optimized reaction parameters, 15% Co–Al₂O₃ retains its catalytic activity up to 8 cycles of catalysis without losing its chemical integrity. The reaction mechanism is proposed based on a structure–photothermal conversion-catalytic activity relationship study and a few control experiments. The design and development of a photocatalyst from the earth-abundant Al element under user-friendly conditions make this approach sustainable for the CO₂ economy.

In this study, we apply TD-DFT and DFT calculations to explore the mechanistic details of O₂ evolution in an artificial system that closely resembles Photosystem II (PSII). The reaction involves mononuclear Mn(III) complex [Mn(salpd)(OH₂)]⁺ and p-benzoquinone under light-driven conditions. Our calculations reveal that the Schiff-base ligand salpd plays a crucial role in several key steps of the reaction, including the light-mediated oxidation of [Mn(salpd)(OH₂)]⁺ to [Mn(salpd)(OH)]⁺ by p-benzoquinone, the subsequent oxidation of [Mn(salpd)(OH)]⁺ to the key Mn(V) intermediate [Mn(salpd)(O)]⁺, and the critical O–O bond formation step. This role is primarily due to the high propensity of the salpd ligand to undergo oxidation by one unit. This characteristic allows the salpd ligand to reduce Mn(IV) in the intermediate [Mn(salpd)(OH)]⁺ to Mn(III), triggering a Jahn–Teller effect that increases the ionic character of the hydroxide ligand. This transformation makes the resulting complex a strong nucleophile, facilitating O–O bond formation through a reaction between [Mn(salpd)(OH)]⁺ and [Mn(salpd)(O)]⁺ with a moderate overall activation free energy of 18.6 kcal/mol. The mechanistic insights presented in this study may provide a useful foundation for developing novel systems that catalyze water oxidation under light-driven conditions, mimicking Photosystem II, and could potentially contribute to advancements in sustainable energy generation.

Bismuth oxychloride (BiOCl) is known for its unique layered microstructure, which plays a pivotal role in enhancing its photocatalytic properties. This study introduces a novel strategy for controlling the phase composition, facet orientation, and oxygen vacancy formation in BiOCl through precise pH adjustment during the synthesis. By employing a hydrothermal method, we systematically varied the pH to produce distinct BiOCl phases and conducted detailed structural and photocatalytic analyses. Remarkably, BiOCl synthesized at pH = 7 demonstrated superior photocatalytic activity on rhodamine B (RhB) degradation, which can be attributed to the coexposure of the (001) and (110) facets, as well as an increased concentration of oxygen vacancies. Density functional theory study also revealed that a high concentration of oxygen vacancies leads to enhanced charge separation, which is beneficial for photocatalytic activity. These results indicate that optimizing the pH during synthesis is a viable approach to enhancing the photocatalytic efficiency of BiOCl, offering significant potential for advanced applications in environmental remediation and solar energy conversion.

Environmental concerns are driving the development of eco-friendly and effective methods for contaminant monitoring and remediation. In this study, a lanthanide porphyrin-based MOF with dual fluorescence sensing and photocatalytic properties was synthesized and applied for the detection and combined removal of Cr(VI) and ciprofloxacin (CIP). Using different excitation wavelengths, the material exhibited selective detection of Cr(VI) via fluorescence quenching and CIP through fluorescence enhancement. The variation in color intensity of Tb-MOF on 3D EEM spectra enabled simultaneous detection of both contaminants. Additionally, Tb-MOF demonstrated a synergistic removal effect, achieving over 95% removal rates of Cr(VI) and CIP within 90 min, with consistent sensing and catalytic performance across four cycles. Mechanistic investigations revealed that (i) strong coordination between Tb³⁺ and CIP altered the surface potential of Tb-MOF, enhancing Cr(VI) adsorption; (ii) as an efficient electron acceptor, Cr(VI) promoted electron transfer and its reduction to Cr(III); and (iii) superoxide radicals generated via a type I mechanism played a key role in CIP degradation. This research underscores the potential of Tb-MOF as a multifunctional platform for simultaneous detection and synergistic remediation of mixed pollutants.

Three Sm(II) dibenzo-24-crown-8 (db24c8) complexes were synthesized in anhydrous, air-free conditions via the reaction of SmI₂ with db24c8 and tetrabutylammonium tetraphenylborate ([TBA][BPh₄]; where needed) in acetonitrile (CH₃CN), dimethoxyethane (DME), and tetrahydrofuran (THF) to yield [Sm(db24c8)(CH₃CN)₂][BPh₄][I]·CH₃CN, [Sm(db24c8)(DME)]I₂, and [Sm(db24c8)(THF)₂]I₂, respectively. In each case, a 10-coordinate, staggered dodecahedral (2:6:2) environment is formed around the Sm²⁺ center that is completed by either two solvent molecules (CH₃CN or THF) or one bidentate solvent molecule (DME). Inner-sphere solvent molecules can be excluded by reacting SmI₂ with db24c8 in 1:3 THF:toluene to yield Sm(db24c8)I₂. This molecule features a distorted, eight-coordinate, hexagonal pyramidal Sm²⁺ metal center, where the coordinated db24c8 molecule shows a torsion angle unexpectedly close to the 180° antiperiplanar arrangement and two uncoordinated db24c8 oxygen atoms. Solution UV–vis–NIR measurements demonstrate that Sm²⁺ is a good size match for the cavity of various db24c8 conformations and that Eu²⁺ and Yb²⁺ exhibit competition between acetonitrile solvation and the Eu²⁺ and Yb²⁺/db24c8 complexes in solution. During excitation by 546 nm light, both [Sm(db24c8)(DME)]I₂ and [Sm(db24c8)(THF)₂]I₂ exhibit mixed 5d → 4f and 4f → 4f emission at 20 °C and exclusively 4f → 4f at −180 °C, whereas Sm(db24c8)I₂ only shows 5d → 4f emission regardless of temperature. Photoluminescence from [Sm(db24c8)(CH₃CN)₂][BPh₄][I]·CH₃CN is quenched.

Lanthanide(III) complexes with two-photon absorbing antennas are attractive for microscopy imaging of live cells because they can be excited in the NIR. We describe the synthesis and luminescence and imaging properties of two Eu³⁺ complexes, mTAT[Eu·L-CC-Ar–Cz] and mTAT[Eu·L-Ar–Cz], with (N-carbazolyl)-aryl-alkynyl-picolinamide and (N-carbazolyl)-aryl-picolinamide antennas, respectively, conjugated to the TAT cell-penetrating peptides. Contrary to what was previously observed with related Eu³⁺ complexes with carbazole-based antennas in a mixture of water and organic solvents, these two complexes show very low emission quantum yield (Φ_Eu < 0.002) in purely aqueous buffers. A detailed spectroscopic study on mTAT[Eu·L-Ar–Cz] reveals that the quantum yield of emission is strongly polarity dependent─the less polar the medium, the higher the quantum yield─and that the emission quenching in water is likely due to a photoinduced electron transfer between the excited carbazole-based antenna and Eu³⁺ that efficiently competes with the energy transfer process. Nevertheless, mTAT[Eu·L-Ar–Cz] shows a significant two-photon cross-section of 100 GM at 750 nm, which is interesting for two-photon microscopy. The live cell imaging properties of mTAT[Eu·L-Ar–Cz] and the two other conjugates were investigated. Cytosolic delivery was clearly evidenced in the case of mTAT[Eu·L-Ar–Cz] when cells are coincubated with this compound and a nonluminescent dimeric TAT derivative, dFFLIPTAT.

Enhancing the optical anisotropy of compounds has attracted significant interest in the optical field. Sn-centered crystals, containing stereochemically active lone pairs, are widely regarded as promising birefringent materials. In this study, we successfully synthesized two novel Sn-centered mixed halide birefringent crystals, NaSn₂F₄Br and Na₂Sn₂F₅I. These crystals, composed of Sn-centered mixed halide polyhedra, exhibit more than a 2-fold increase in birefringence from NaSn₂F₄Br to Na₂Sn₂F₅I. Among all known Sn-centered halides, the Na₂Sn₂F₅I crystal demonstrates the highest birefringence (Δn = 0.408@546 nm). Theoretical calculations indicate that the exceptional optical properties of Na₂Sn₂F₅I arise from the large polarization anisotropy induced by the Sn–I bond within the Sn-centered polyhedra. These findings provide valuable insights for the development of high-quality birefringent crystal materials in Sn-centered mixed halide systems.

In the field of structural chemistry, crystals containing the [OM₄] tetrahedra (M = metal cation) structure have been well documented. However, compounds containing both [OPb₄] tetrahedra and π-conjugated groups are less reported due to their structural complexity. In this work, a new lead borate–nitrate, Pb₉O₄(BO₃)₂(NO₃)₄, has been synthesized by a high temperature melt method. Notably, the structure of Pb₉O₄(BO₃)₂(NO₃)₄ contains special [O₈Pb₁₈]_∞ chains formed by the [OPb₄] tetrahedra. This compound possesses a large optical anisotropy with birefringence of Δn = 0.117 at 546 nm.

Several studies were focused on the application of MIL-100(Fe) (Fe₃O(OH)(H₂O)₂(BTC)₃, H₃BTC is 1,3,5-benzene tricarboxylic acid) in the photo-Fenton reaction, but it still suffers from low efficiency. In this work, MIL-100(Fe) was synthesized at ambient conditions and low pHs using Fe(II) precursors in homogeneous aqueous media to develop a sample with high activity in the photo-Fenton reaction, even better than Fe-porphyrin metal–organic frameworks. The as-synthesized sample is highly crystalline with 30.6% Fe(II)/Fe(III) mixed-valency (equal to 0.92 Fe per node). Since the Fe(II) sites are inserted in the framework during the synthesis process, a lower activation temperature (120 °C) is required to create open metal sites. This strategy can tune the chemistry of Fe-nodes which in turn can significantly improve the photo-Fenton efficiency of the material. Moreover, the mentioned synthesis conditions can optimize the textural properties of the material to increase the diffusion rate of the analytes into the pores and the accessibility of Fe-nodes. Overall, here, it was proved that the chemistry of Fe-nodes of MIL-100(Fe) can be tuned through the in situ generation of high ratio of mixed-valence sites and textural properties to reach high efficiencies in the photo-Fenton reaction.

Using ab initio based molecular dynamics and electronic structure calculations, we show that Zn impurities in hydrated amorphous calcium carbonate (ACC) have a much lower coordination number than other divalent impurities due to covalent interactions between the 3d Zn shell and the oxygen atoms of the carbonate and water groups. The local structure around Zn in ACC, including the predicted low coordination number, is confirmed by X-ray absorption spectroscopy of synthetic Zn-bearing ACC. The strong Zn–O chemical interaction leads to substantial water dissociation and slightly disrupts the hydrogen bonding network. Implications of Zn²⁺ incorporation for ACC stability are discussed.

This paper reports the synthesis of the first series of terminal phosphido Ni(II) complexes supported by the β-diketiminato ligand [ⁱPrNN] (where ⁱPrNN = 2,4-bis(2,6-diisopropylphenylimido)pentyl). Neutral mononuclear Ni(II) complexes [ⁱPrNN]Ni–PPh₂ (2) and [ⁱPrNN]Ni–PAd₂ (3) were obtained from the reaction of [ⁱPrNN]NiBr₂Li(thf)₂ (1) with the R₂PM (R = Ph, 1-adamantyl (Ad); M = Li, K) phosphide reagents. The structures of the synthesized compounds were determined by single-crystal X-ray diffraction, which revealed that the Ni center in these terminal phosphido complexes is three-coordinate with an almost planar geometry when R = Ph and a pyramidal geometry when R = Ad. The reactivity of the synthesized complexes was also studied in a range of bond forming reactions, including P–C and P–P bonds.

A Pt(II) aqua complex 5^MSN supported by mesoporous silica nanoparticle (MSN)-immobilized sulfonated CNN pincer ligand featuring a rigid SiO₃ tether was prepared. This hybrid material was tested as a catalyst in H/D exchange reactions of C(sp²)–H bonds of selected aromatic substrates and D₂O-2,2,2-trifluoroethanol-d₁ (TFE-d₁) mixtures or CD₃CO₂D acting as a source of exchangeable deuterium. The catalyst immobilization served as a means to not only enable the catalyst’s recyclability but also minimize the coordination of sulfonate groups and the metal centers originating from different catalyst’s moieties that would preserve reactive Pt^II(OH₂) fragments needed for catalytic C–H bond activation. In the same vein, the use of a rigid tether was expected to help suppress potentially strong intraparticle coordination of MSN’s silanol groups and Pt(II) that could inhibit the catalytic H/D exchange. The particle size distribution, porosity, surface area, elemental composition of 5^MSN, and the pincer ligand loading were characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray (EDX) analysis, N₂ sorption, and alkaline digestion with subsequent ¹H NMR and ESI-MS analyses of the resulting solutions. It was found that 5^MSN is a more active catalyst of the H/D exchange reactions of benzene, thiophene, anisole, and/or toluene than analogous molecular Pt(II) aqua complexes 1 and 5, which exhibited 2–10 times lower TON after 24 h of reaction under otherwise identical conditions. The greater activity and chemical robustness of 5^MSN allowed us to effectively use the catalyst in the H/D exchange reactions with acetic acid-d₄, which is a more readily available source of exchangeable deuterium than TFE-d₁ at 120 °C. The recyclability of 5^MSN was also demonstrated.

High-entropy ceramics hold promise for application as thermal barrier coating materials. However, a key challenge in practical applications lies in the low fracture toughness compared to that of yttria-stabilized zirconia (YSZ). Herein, we designed (Hf,Zr,Ce,M)O_2−δ–Al₂O₃ (M = Y, Ca, and Gd) ceramic composites by following a set of fundamental guidelines. First-principles calculations predicted that the inclusion of Al₂O₃ in compositions containing the other four binary oxides decreased the propensity for single high-entropy phase formation. Instead, it increased the potential for Al₂O₃ to form a second phase within the high-entropy ceramic matrix, compared to compositions without Al₂O₃. Ceramic composites consisting of the Al₂O₃ second phase in a high-entropy fluorite oxide (Hf,Zr,Ce,M)O_2−δ matrix were synthesized in situ via conventional solid-state reactions from the five constituent binary oxides. Both the hardness and fracture toughness of the ceramic composites were enhanced due to toughening mechanisms from the discrete Al₂O₃ particles, microcracks, and crack deflections. Additionally, the ceramic composites exhibited coefficients of thermal expansion and thermal conductivities comparable with those of YSZ. Our findings demonstrated the potential of the high-entropy (Hf,Zr,Ce,M)O_2−δ–Al₂O₃ ceramic composites for advanced thermal barrier coating materials and offered a possible approach to reinforce other high-entropy oxide-based ceramic systems.

The reaction of the diborabenzene (DBB) nickel(0) pogo-stick complex [(η⁶-DBB)Ni(CO)] (II) with a large excess of [Ni(CO)₄] yields the dark green, unstable dinickel(0) complex [(η⁶-DBB)Ni(μ-CO)Ni(CO)₃] (1), which loses one CO ligand to yield the purple, bimetallic Ni⁰₂ half-sandwich complex [(η⁶-DBB)Ni₂(μ-CO)(η¹-CO)₂] (2). The addition of the chromium aminoborylene complex [(OC)₅Cr{BN(TMS)₂}] (TMS = trimethylsilyl) to II does not result in the expected borylene transfer but in the formation of the black Ni⁰–Cr⁰ complex [(η⁶-DBB)Ni(μ-CO)Cr(CO)₅] (3), alongside the dimeric iminoborane [(TMS)BN(TMS)]₂ (4), which results from the rearrangement of the released BN(TMS)₂ aminoborylene moiety. Furthermore, the oxidative addition of methyl triflate (MeOTf) to II leaves the (η⁶-DBB)Ni moiety intact and provides the ionic Ni^II half-sandwich complex [(η⁶-DBB)NiMe(CO)]OTf (5), while reaction with pentaphenylborole (PPB) yields the unique, dark-blue, unsymmetrical sandwich complex [(η⁶-DBB)Ni₂(μ-CO)₂(η⁵-PPB)] (6). DFT calculations point toward 6 being a dinickel(0) complex with a neutral aromatic DBB and a neutral antiaromatic PPB ligand.

The glassy state of inorganic–organic hybrid metal halides combines their excellent optoelectronic properties with the outstanding processability of glass, showcasing unique application potential in solar devices, display technologies, and plastic electronics. Herein, by tailoring the organic cation from N-phenylpiperazine to dimethylamine gradually, four types of zero-dimensional antimony halides are obtained with various optical and thermal properties. The guest water molecules in crystal (N-phenylpiperazine)₂SbCl₆·Cl·5H₂O lead to the largest distortion of the Sb-halogen unit, resulting in the red emission different from the yellow emission of other compounds. More importantly, the water molecule-induced hydrogen-bond network in (N-phenylpiperazine)₂SbCl₆·Cl·5H₂O would prolong the relaxation time into an equilibrium state, resulting in the formation of the glassy state. This is different from the previous strategy of adopting large organic cations for glass transition. Through rheological studies, we shape an initial understanding of the underlying kinetics in inorganic–organic hybrid metal halide glass. This work provides a simpler and more convenient approach for developing inorganic–organic hybrid metal halides with superior processing performance.

The low sulfur selectivity of Fe-based H₂S-selective catalytic oxidation catalysts is still a problem, especially at a high O₂ content. This is alleviated here through anchoring FeO_x nanoclusters on UiO-66 via the formation of Fe–O–Zr bonds. The introduced FeO_x species exist in the form of Fe^III and Fe^II. Therein the Fe^III–O species are the predominant active sites for H₂S-oxidation. The formed Fe–O–Zr bonds strengthen the redox cycle of Fe^III/Fe^II through promoting electron transfer from Fe to Zr. The Fe^II–O species can activate molecular oxygen to oxidize H₂S into elemental S, which accelerates the formation rate of atomic S, hindering its further oxidation into SO₂. The combination of these factors empowers the catalysts, enabling 100% H₂S conversion and 98.2% sulfur yield. The catalyst also has satisfactory stability with the sulfur selectivity only decreasing from 98.2% to 91.3% after the reaction going on 50 h. The decreased sulfur selectivity might be caused by the deterioration of pores and the deposition of elemental S on the surface. The former hinders the diffusion of sulfur oligomers timely from pores to the gas phase, while the latter is suspected to capture electrons to promote its further reaction with molecular oxygen.

Dative bonds are typically polar, weaker, and longer than electron-sharing covalent bonds. The intriguing diatomic BeF^– anion uniquely exhibits triple Be–F dative bonding with a considerable bond dissociation energy (BDE) of 88 kcal/mol. Here, we report exceptionally strong dative-bonded systems, [CO₃]BeF^– and [C₂O₄]BeF^–, with BDE values exceeding 155 kcal/mol by integrating [CO₃] and [C₂O₄] groups into the BeF^– framework. These designed C_2v-symmetric molecules represent the lowest-energy configurations and maintain similar triply bonded Be–F interactions with orbital characteristics and bond distances closely resembling those in BeF^–. Chemical bonding analysis reveals that [CO₃] and [C₂O₄] groups significantly withdraw s-type nonbonding electrons from Be, which minimizes valence shell electron repulsion from the F^– to Be interactions. This reduction in Pauli repulsion between the closed-shell fragments in [CO₃]BeF^– and [C₂O₄]BeF^–, compared to that of BeF^–, establishes a new record in dative bond strength and offers substantial insights into dative bonding mechanisms. The identified high thermodynamic and kinetic stability of these systems positions them as promising candidates for experimental detection in low-temperature matrices or the gas phase.

A new [Dy₃Bi₈O₆Cl₃(saph)₉] (1) Werner-type cluster has been prepared, which is the first Dy^III/Bi^III polynuclear compound with no metal–metal bond and one of the very few Ln^III–Bi^III (Ln = lanthanide) heterometallic complexes reported to date. The molecular compound 1 has been deliberately transformed to its 1-D analogue [Dy₃Bi₈O₆(N₃)₃(saph)₉]_n (2) via the replacement of the terminal Cl^– ions by end-to-end bridging N₃^– groups. The overall metallic skeleton of 1 (and 2) can be described as consisting of a diamagnetic {Bi₈} unit with an elongated trigonal bipyramidal topology, surrounded by a magnetic {Dy₃} equilateral triangle, which does not contain μ₃-oxo/hydroxo/alkoxo groups. Detailed magnetic studies in a microcrystalline sample and a single crystal of 1 revealed a rare two-step hysteresis loop at various low temperatures and field-sweep rates, with the steps located at zero and ±0.26 T fields providing a measure of intermolecular interactions. Extended ab initio calculations unravel the dominant pathways of magnetization relaxation, as well as the type and magnitude of the magnetic exchange interactions between the Dy^III centers and the orientation of their anisotropy axes, thus rendering the {Dy₃} unit of 1 as a rare triangle among its congeners with a nontoroidal magnetic state. The combined results demonstrate the potential of heterometallic lanthanide/post-transition metal chemistry to provide molecule-based materials with unprecedented structures and compelling methods to rationalize the obtained magnetic properties.

The crystal structure determines the properties of compounds and materials, although one can find simple yet industrially relevant compounds such as potassium acetate (KOAc) and its hydrates for which the properties and even the composition still remain misunderstood, owing to the lack of structural data. In this study, the crystal structures of KOAc polymorphs and hydrates were determined for the first time. The water content in the crystal hydrates was reliably determined revealing two new phases 3KOAc·2H₂O and KOAc·xH₂O (x = 0.38–0.44), instead of the “sesquihydrate” and “hemihydrate” that for a century were believed to be the main hydrated forms of KOAc at ambient temperature. The number and nature of phase transitions were clearly established, and the hydration–dehydration processes were studied in detail by variable-temperature X-ray diffraction and thermal analyses.

A new series of P2₁2₁2₁ adelite-type LnCo(GeO₄)(OH) (Ln = La-Sm) single crystals were grown by a high-temperature, high-pressure hydrothermal method (650 °C and 100 MPa). Single-crystal diffraction refinements yielded chiral one-dimensional (1D) chains of Co²⁺ along the a axis with an average 2.98 Å separation between Co²⁺ centers in the [CoO₂(OH)₂]_∞ ribbon chains. A three-dimensional (3D) superstructure is formed by a bridging lanthanide-germanium framework formed by two unique alternating 5.83 and 6.00 Å distances between interchain Co²⁺ centers along the a axis. Magnetic studies of the S = 3/2 Co²⁺ chains in LaCo(GeO₄)(OH) revealed a highly anisotropic structure with a common Néel temperature of 32 K. Additionally, a spin-flip transition occurs at 2 K when a 7.3 T field is applied along the chain. Zero-field cooled susceptibility at this critical field resulted in a complex intermediate state consisting of three unique antiferromagnetic transitions at 3, 8, and 16 K. The spin exchanges of LaCo(GeO₄)(OH) evaluated by density functional theory calculations show the presence of spin frustration in the 1D chains, which can lead to a cycloidal magnetic structure within the plane of [CoO₂(OH)₂]_∞ chains. The observed magnetic properties are explained by considering the competition between the 1D intrachain and 3D–1D interchain antiferromagnetic interactions.

The Pd–Zn γ-brass phase provides exciting opportunities for synthesizing site-isolated catalysts with precisely controlled Pd active site ensembles. Introducing a third metallic element into the γ-brass lattice further perturbs the catalytic active site ensembles. Here, we introduce coinage metallic elements M (M = Cu, Ag, and Au) into the Pd–Zn γ-brass phase and investigate the site occupation factors of each element in the γ-brass lattice. The CALculation of PHAse Diagrams (CALPHAD) modeling approach supported by energetics predicted by the density functional theory and X-ray and neutron diffraction with Rietveld refinement were used to identify the SOF on each Wyckoff site for various M amounts alloyed into the Pd–Zn γ-brass phase. The present analysis unveils the strong preference for Pd occupying the outer tetrahedral (OT) site in the γ-brass lattice, while the coinage metallic elements tend to substitute for Zn on the octahedral (OH) site. The determination of site occupancy in the bulk M–Pd–Zn γ-brass phase provides opportunities to investigate and tailor potential catalytically active site ensembles in the γ-brass phase materials.

In the field of solar energy storage, photocatalytic ammonia production is a next-generation technology. The rapid recombination of charges and insignificant utilization of the sunlight spectrum are bottlenecks of effective photocatalytic N₂ fixation. The introduction of impurities in the crystal lattice and the development of heterojunctions could effectively segregate carriers and improve the solar-light-harvesting capability, which can boost NH₃ generation. Therefore, in this work, three-element doping by S, C, and N was carried out to rectify the photocatalytic feature of TiO₂, and then it was combined with a broad-light-absorption Cu₉S₅ semiconductor. The synthesized S,C,N-doped TiO₂/Cu₉S₅ nanocomposites with a QD size of almost 7.17 nm exhibited outstanding ability in photocatalytic N₂ reduction, and the generation of NH₃ reached 23 567 μmol L^–1 g^–1 without sacrificial agents, which was 5.67 and 2.11 folds larger than TiO₂ and Cu₉S₅, respectively. The promoted performance of the nanocomposite was ascribed to doping three elements and the construction of a Z-scheme system, which attains efficacious separation of carriers and supplies a dedicated path for carrier migration. This research not only supports a novel, sustainable, and facile strategy for the synthesis of S,C,N-TiO₂/Cu₉S₅ nanocomposites with inorganic materials and biocompatible characteristics but also provides new insights into the design and construction of TiO₂-based materials through nonmetal and low-cost three-elemental doping for photocatalytic nitrogen fixation.

The substantial structural defects frequently observed in fabricated transition-metal dichalcogenide (TMD) samples inevitably affect the device performance. The molybdenum telluride (MoTe₂) monolayer can easily generate phase transitions between the 1H and 1T′ phases due to a small energy barrier. However, distinguishing and identifying various defects during experiments is challenging. In this study, we comprehensively explore point defects and grain boundaries in MoTe₂ using first-principles calculations. We simulate the corresponding scanning tunneling microscopy (STM) and transmission electron microscopy (TEM) images to characterize different types of defects. The same type of point defects in the 1T′ phase exhibits lower formation energies than those in the 1H phase. The grain boundaries of the 1T′ phase form more easily, with corresponding formation energies ranging from 0.07 to 0.14 eV/Å. The partial densities of states indicate that the electronic properties of the 60°, 60°-glide, and 120° grain boundaries (GBs) in the 1T′ phase are similar, while various types of defect rings in the 1H phase differ significantly. Our theoretical results effectively reduce the primary cost of characterizing defects and provide essential guidance for experimental references and identifications.

The extent of coordination-induced bond weakening in aquo and hydroxo ligands bonded to a molybdenum(III) center complexed by a dianionic, pentadentate ligand system was probed by reacting the known complex (B₂Pz₄Py)Mo(III)-NTf₂, I, with degassed water or dry lithium hydroxide. The aquo adduct was not observed, but two LiNTf₂-stabilized hydroxo complexes were fully characterized. Computational and experimental work showed that the O–H bond in these complexes was significantly weakened (to ≈57 kcal mol^–1), such that these compounds could be used to form the diamagnetic, d² neutral terminal molybdenum oxo complex (B₂Pz₄Py)Mo(IV)O, 2, by hydrogen atom abstraction using the aryl oxyl reagent ArO• (Ar = 2,4,6-tri-tert-butylphenyl). Oxidation of the neutral hydroxo derivative further facilitated the production of 2 by significantly enhancing the acidity of the hydroxyl proton. Speciation in these processes was probed by electrochemical and chemical experiments. The terminal oxo complex 2 was smoothly oxidized by one electron to the cationic [(B₂Pz₄Py)Mo(V)O]⁺[A]⁻ derivatives [2]⁺[A]^– (A = NTf₂ or Al[OC(CF₃)₃]₄ depending on the oxidizing agent used). Both Mo(IV) and Mo(V)⁺ oxo complexes were fully characterized with their nucleophilic and electrophilic reaction behavior probed by conducting reactions with the Lewis acid B(C₆F₅)₃ and the Lewis base PPh₃. Neutral oxo complex 2 reacts only with the Lewis acid, while the cationic [2]⁺[A]^– reacts only with PPh₃, the former by adduct formation and the latter via phosphine oxidation.

We present the synthesis of metal oxide coordination networks based on Preyssler-type polyoxoanions ([NaP₅W₃₀O₁₁₀]^14– and [NaP₅MoW₂₉O₁₁₀]^14–) bridged with metal–aquo complexes ([M(H₂O)_n]^m+, M^m+ = Co²⁺, Ni²⁺, Zn²⁺, Y³⁺), induced by electrochemical reduction. Networks bridged with first-row transition metals are isostructural with a previously reported Co-bridged structure, while the Y³⁺-bridged structure is new. All networks feature an uncommon binding motif of the metal cation to the oxygen atoms at cap positions, which we hypothesize is due to increased electron density at the cap upon reduction. Oxidation of a Zn²⁺-bridged network resulted in a new structure in which Zn²⁺–O_cap bonds are lost, indicating the importance of reduction in the connectivity of these polyoxometalate-based coordination networks.

Information storage and encryption are the key technologies for modern information transmission. However, most optical information storage technologies based on long persistent luminescent (PersL) only have one fixed response mode, which is easy to imitate, limiting their security in advanced information storage and encryption applications. Besides, the cost of rare earth-doped PersL materials restricts their wide application. Therefore, exploring non-rare earth-doped multimode PersL phosphors is an urgent and important topic. In this work, a novel SrGa₂Ge₂O₈:Cu²⁺ (SGGO:Cu²⁺) phosphor with yellow–green PersL at 535 nm and near-infrared emission excited by ultraviolet light is designed. Furthermore, the two luminescence peaks of SGGO:0.007Cu²⁺ exhibit discriminable thermal quenching characteristics. Prominently, an outstanding photochromic performance from white to gray within 60 s under 254 nm light is found. The phosphor also has good bleaching and recovery ability under the irradiation of 450 nm blue light or heating treatment. Finally, the yellow–green PersL combined with thermochromism and reversible white-to-gray photochromism provides a promising multimode luminescent material, demonstrating the potential for multimode optical information storage and encryption applications.

Developing new photocatalysts for the selective oxidation of thioethers to high-value-added sulfoxides under low-oxygen mild conditions is a promising but challenging strategy. Here, a new polyoxometalate-based metal–organic framework (POMOF), CoBW₁₂–TPT, was successfully synthesized, wherein continuous π···π stacking interactions and direct coordination bonds not only strengthen the framework's stability but also accelerate electron transfer. A series of experiments and theoretical studies, including control experiments, kinetic studies, electrochemical spectroscopic analyses, and electron paramagnetic resonance, revealed the synergistic catalytic effect among Co(II) metal centers, BW₁₂O₄₀^5–, and the photosensitizer TPT. CoBW₁₂–TPT was applied in the photocatalytic oxidation of thioethers to sulfoxides. Under irradiation, the photoinduced electron transfer of POMOF leads to the generation of superoxide radicals from O₂, which controls the selective generation of sulfoxide compounds in the photocatalytic desulfurization reaction and shows good activity. In particular, it can be applied to the construction of some drug molecules such as Modafinil and Albendazole Oxide.

Sodium borohydride dihydrate (NaBH₄·2H₂O) forms through dihydrogen bonding between the hydridic hydrogen of the BH₄^– ion and the protonic hydrogen of the water molecule. High-pressure structural changes in NaBH₄·2H₂O, observed up to 11 GPa through X-ray diffraction and Raman scattering spectroscopy, were analyzed to assess the influence of dihydrogen bonds on its crystal structure. At approximately 4.6 GPa, certain dihydrogen bonds were broken, leading to the decomposition of NaBH₄·2H₂O into ambient pressure phase of NaBH₄ (α-NaBH₄) and ice VII. Upon further compression beyond 6.6 GPa, NaBH₄ gradually transformed into its high-pressure phase, γ-NaBH₄. During decompression, γ-NaBH₄ reverted to α-NaBH₄ at the pressure between 4.4 and 2.7 GPa and subsequently reacted with ice VII, resulting in the recrystallization of NaBH₄·2H₂O. This recrystallization, occurring during decompression from 4.4 to 2.7 GPa, is identical to the starting sample and can be termed “decompression-induced recrystallization”, highlighting the strength of the dihydrogen bonds in NaBH₄·2H₂O. In addition, density functional theory calculations were used to evaluate the pressure dependence of hydrogen–hydrogen (H–H) distances in NaBH₄·2H₂O. As pressure increased, the number of dihydrogen bonds within the unit cell rose from seven at near-ambient pressure to 12 at approximately 4.5 GPa just before the dehydration, indicating that each hydrogen atom in the water molecule formed dihydrogen bonds with around three hydrogens from the BH₄^– ions just prior to dehydration. Such pressure tuning of dihydrogen bonds may lead to the creation of new energy storage materials.

The protonolysis and redox reactivity of a Ce(IV) carbonate complex supported by the Kläui tripodal ligand [(η⁵-C₅H₅)Co{P(O)(OEt)₂}₃]⁻ (L_OEt^–) have been studied. Whereas treatment of [Ce(L_OEt)₂(CO₃)] (1) with RCO₂H afforded [Ce(L_OEt)₂(RCO₂)₂] (R = Me (2), Ph (3), 2-NO₂C₆H₃ (4)), the reaction of 1 with PhCH₂CO₂H resulted in formation of a mixture of Ce(IV) (5) and Ce(III) (6) carboxylate species. In benzene in the dark, 5 was slowly converted into 6 via Ce(IV)-O(carboxylate) homolysis. Recrystallization of a mixture of 5 and 6 from hexane led to isolation of yellow crystals of 6 that were identified as [Ce(L_OEt)₂(PhCH₂CO₂)]. Treatment of 1 with sulfamic acid, trifluoroacetamide, and trifluoromethanesulfonamide gave [Ce(L_OEt)₂(SO₃NH)₂] (7), [Ce(L_OEt)₂(CF₃CONH)₂] (8), and [Ce(L_OEt)₂(CF₃SO₂NH)₂] (9), respectively. The crystal structures of 2, 4, and 6–8 have been determined. H atom transfer (HAT) of 2,6-di-tert-butylphenol and 9,10-dihydroanthracene (DHA) with 1 afforded 3,3′,5,5′-tetra-tert-butyldiphenoquinone and anthracene, respectively. The oxidation of DHA with 1 under air yielded anthracene and anthraquinone. While 1 is stable in acetonitrile, it is readily reduced to a Ce(III) species in tetrahydrofuran. In air, 1 reacted with tetrahydrofuran to produce tetrahydrofuran hydroperoxide that can reduce the Ce(IV) carbonate rapidly. Upon irradiation with blue LED light, the Ce(IV)-L_OEt carboxylate complexes underwent facile decarboxylation via Ce–O homolysis. 1 proved to be an efficient catalyst precursor for decarboxylative oxygenation of arylacetic acids. For example, irradiation of phenylacetic acid with blue LED light in the presence of 5 mol % of 1 under air afforded benzyl alcohol and benzaldehyde in 10 and 90% yield, respectively.

In this work, bimetallic organic frameworks NH₂-MOFs(Fe, Ti) with different Fe³⁺/Ti⁴⁺ molar ratios were prepared by a hydrothermal method for the synchronous redox transformation of Cr(VI) and As(III). These results showed that NH₂-MIL-125(Ti) was less effective in the photocatalytic removal of Cr(VI), whereas NH₂-MIL-88B(Fe) was less effective in the photocatalytic oxidative removal of As(III). Due to the introduction of Fe³⁺, the photocatalytic reduction removal of Cr(VI) (23.04 → 42.56%) and the photocatalytic oxidation removal of As(III) (5.58 → 26.09%) by NH₂-MOFs(Fe, Ti) were significantly enhanced. Among them, NH₂-MIL-88B(Fe_0.6Ti_0.4) exhibited the best performance in the photoreduction of Cr(VI) and photo-oxidation of As(III), which balanced the insufficiency of monometallic MOFs(Fe/Ti). In this case, the total removal of Cr(VI) and As(III) by NH₂-MIL-88B(Fe_0.6Ti_0.4) was found to be 94.19 and 83.54%, respectively. The excellent photocatalytic property could account for the ligand-to-metal charge transfer (LMCT), where photogenerated e^– generated by −NH₂ group excitation was transferred to the active site Fe–O clusters, as well as e^– transported along Ti → O → Fe (metal-to-metal charge transfer, MMCT). Therefore, the synergetic effect of LMCT and MMCT could efficiently inhibit the recombination of e^––h⁺ pairs, improving the photocatalytic performance of NH₂-MOFs(Fe, Ti).

Photothermal therapy is a promising strategy for treating tumors and bacterial infections by using light irradiation to locally heat tissues. Metalloisoporphyrinoid materials have been investigated for their use as singlet oxygen photosensitizers for photodynamic therapy but remain underexplored as photothermal agents. Recently, two metallophlorin and two metalloisocorrole materials were found to have strong near-infrared absorbance, with low photoluminescent quantum yields, suggesting high rates of nonradiative decay. Here we demonstrate that when encapsulated into aggregated organic nanoparticles (a-Odots), these materials show high photothermal conversion efficiencies between 67.3 ± 8.4 and 75.7 ± 4.1%. When considered alongside their ability to generate singlet oxygen, these materials may show promise as agents for dual photothermal and photodynamic therapy.

As an indispensable member of the reticular material family, metal–carbon-based organometallic frameworks (OMFs) remain largely underexplored, and no chiral OMFs (COMFs) have been reported thus far. Herein, we first report the construction of COMFs from a Pd-isocyanide OMF via nucleophilic addition to the Pd-isocyanide moiety with optically pure amines. The obtained Pd-bis(acyclic diaminocarbene) (Pd-BADC)-derived chiral OMFs display excellent applicability and can be reusable chiral catalysts to highly promote asymmetric Strecker and Suzuki–Miyaura cross-coupling reactions in a heterogeneous way. We anticipate that this type of chiral reticular material will be applicable to a broad range of asymmetric catalytic applications, and this appealing synthetic strategy will likely provide access to more other such materials with unprecedented structures and catalytic activities.

Photocatalytic reactive oxygen species (ROS) evolution with Bi₅O₇I still suffers from sluggish charge carrier dynamics and limited light absorption. Herein, abundant oxygen vacancies (OVs) were introduced into the microflower-like Bi₅O₇I, and its ROS generation toward organic dye degradation under the synergistic effect of visible light and ultrasound irradiation was investigated. Benefiting from the broadened visible-light absorption range, stronger piezoresponse, and higher carrier transport efficiency in OV-enriched Bi₅O₇I (2-PEG-Bi₅O₇I), both its photocatalytic and piezocatalytic degradations were improved. More importantly, its piezo-photocatalytic degradation performance was greater than the sum of the corresponding photocatalysis and piezocatalysis, indicating a strong coupling effect. In addition, the piezo-photocatalytic yield of ^•O₂^– with 2-PEG-Bi₅O₇I was 1.5 times higher than that with Bi₅O₇I, and it was also 4.3 and 3.1 times higher than its single photocatalysis and piezocatalysis, respectively. Interestingly, no noticeable ^•OH was detected in the case of visible-light irradiation, while the piezocatalytic and piezo-photocatalytic yields of ^•OH were 3.6 and 5.3 μmol g^–1 h^–1, respectively, with OV-enriched Bi₅O₇I, surpassing the pristine Bi₅O₇I as well. This work advances the coupling effect between photocatalysis and piezocatalysis as a new strategy for efficient ROS generation and also discloses the positive role of oxygen vacancies in improving multiresponsive catalysis.

The oxidation of (CH₃)₂NOH (DMH, N,N-dimethylhydroxylamine) is of interest because of the use of this reagent in actinide separations. Here, we report on the aqueous oxidation of DMH by [IrCl₆]^2–, a classic outer-sphere one-electron oxidant. The reaction is subject to adventitious catalysis by Fe²⁺ and Cu²⁺, and this catalysis can be suppressed with 1 mM oxalate. The uncatalyzed reaction yields [IrCl₆]^3– and nitrone (CH₃)N(O)CH₂. The rate law has two terms: one corresponding to oxidation of (CH₃)₂NOH and the other to oxidation of (CH₃)₂NO^–. A mechanism is inferred in which the rate-limiting steps are electron-transfer oxidations of these two DMH forms, leading to their corresponding radicals. The nitrone arises from the oxidation of the DMH radical, (CH₃)₂NO^·.

Amino acids and dipicolinic acid (DPA) are important biomarkers for identifying human health. Establishing rapid, accurate, sensitive, and simple assays is essential for disease prevention and early diagnosis. In this work, a novel Zn(II) metal–organic framework (MOF) with the formula {[Zn₅(μ₃–OH)₂(BTDI)₂(dpp)₂]·dpp·4H₂O·2DMF}_n (JXUST-53, where JXUST denotes Jiangxi University of Science and Technology, H₄BTDI = 5,5′-(benzo[c][1,2,5]thiadiazole-4,7-diyl)diisophthalic acid; dpp = 1,3-di(4-pyridyl)propane) was successfully synthesized via a mixed-ligands strategy. JXUST-53 exhibits a three-dimensional (4,10)-connected deh1 topological structure, which remains stable after soaking in aqueous solutions with different pH values (1–12) and organic solvents for at least 24 h, showing high chemical and pH stability. As a potential fluorescence sensor, JXUST-53 can specifically recognize l-threonine (l-Thr), l-histidine (l-His), and DPA in EtOH solutions through fluorescence enhancement and a blue-shift effect. It is worth noting that JXUST-53 is the first MOF-based fluorescence sensor capable of recognizing l-Thr. In addition, the university logo of JXUST with JXUST-53 deposited on it was printed by aerosol jet printing technology, enabling a portable and convenient method for monitoring DPA. More importantly, JXUST-53 has good biocompatibility and low cytotoxicity to sense l-Thr, l-His, and DPA in living cells.

Atomically precise nanoclusters, distinguished by their unique nuclearity- and structure-dependent properties, hold great promise for applications of energy conversion and electronic transport. However, the relationship between ligands and their properties remains a mystery yet to be unrevealed. Here, the influence of ligands on the electronic structures, optical properties, excited-state dynamics, and transport behavior of Re₁₂S₁₆ dimer clusters with different ligands is explored using density functional theory combined with time-domain nonadiabatic molecular dynamic simulations. The correlation between ligands and the excited-state dynamics of nanoclusters is elucidated. The ligand replacement introduces a built-in electric field at the dimer interface, inhibiting the recombination of excited carriers and increasing the voltage threshold. This study paints a physical picture of the ligand effect on nanoclusters in terms of geometric configuration, electronic structure, optical properties, carrier dynamics, and transport behavior, paving a pathway toward their applications in optoelectronic materials.

Superconducting hydrides exhibiting a high critical temperature (T_c) under extreme pressures have garnered significant interest. However, the extremely high pressures required for their stability have limited their practical applications. The current challenge is to identify high-T_c superconducting hydrides that can be stabilized at lower or even ambient pressures. Here, we propose a strategy for designing high-T_c superconducting hydrides at low pressures by introducing defects into the hydrogen frameworks of clathrate hydrides. We present a type of hydrogen-vacancy structural type AB₃H₂₀ derived from type-I clathrate hydrides and identified a stable NaY₃H₂₀ through high-throughput calculations. Further calculations show that NaY₃H₂₀ is thermodynamically stable above 133 GPa and dynamically stable down to 20 GPa, with a predicted high T_c of approximately 115 K. It significantly reduces the pressure required for stability compared to that of type-I clathrate hydrides with high T_c. Our results provide a foundation for further exploration of high-T_c superconducting hydrides at lower pressures or even ambient conditions.

Alkyl nickel intermediates relevant to catalytic processes often feature agostic stabilization, but relatively little is known about the situation in oligonickel systems. The dinickel(I) complex K[LNi^I₂], which is based on a compartmental pyrazolato-bridged ligand L^3– with two β-diketiminato chelate arms, or its masked version, the dihydride complex [KL(Ni^II–H)₂] that readily releases H₂, oxidatively add methyl tosylate to give diamagnetic [LNi^II₂(CH₃)] (1) with d(Ni···Ni) ≈ 3.7 Å. Structural characterization shows that the methyl group in 1 is bound to one Ni^II and exhibits an intramolecular agostic interaction with the more distant Ni^II. This is supported spectroscopically (viz., a ν(C–H) stretch at 2658 cm^–1 and lowered ¹J_C–H of 114 Hz) and by DFT calculations, including topological analysis of the computed electron density for 1. NMR spectroscopy reveals very fast hopping of the CH₃ group between the two Ni^II ions, which according to DFT has a minute barrier of 4 kcal mol^–1 and proceeds via a planar CH₃ moiety in the transition state (Walden-like inversion). The alkylidene group in K[LNi₂(μ-CHSi(Me₃)₃)], obtained from the reaction of [KL(Ni–H)₂] with N₂CHSiMe₃, is symmetrically bridging. This work provides new insight into the stabilization and dynamics of alkyl ligands at dinickel sites with a constrained metal···metal distance.

The ZSM-5 zeolite is the key active component in high-severity fluid catalytic cracking (FCC) catalysts and is routinely activated by phosphorus compounds in industrial production. To date, however, the detailed structure and function of the introduced phosphorus still remain ambiguous, which hampers the rational design of highly efficient catalysts. In this work, using advanced solid-state NMR techniques, we have quantitatively identified a total of seven types of P-containing complexes in P-modified ZSM-5 zeolite and clearly revealed their structure, location, and catalytic role. The experimental findings indicate that the introduced phosphorus can stabilize a portion of the aluminum atoms in the lattice by forming an energetically favorable framework-bound Si–OH–Al–O–P structure inside the zeolite channels, preserving more acidic bridging hydroxyl groups under the working conditions of the catalyst. Besides, two other types of hydrothermally stable phosphoric acid species (H₃PO₄ and H₄P₂O₇) captured by neighboring silanol groups (H₃PO₄···HO-Si(SiO₄)₃ and H₄P₂O₇···HO-Si(SiO₄)₃) are identified. For the FCC process, the framework-bound Si–OH–Al–O–P structure is proven to be the active site in the conversion of the FCC reactant, while the two phosphoric acid species can promote the yield of C₂–C₄ olefins.

The photophysical properties of six new luminescent tetrahedral Zn(II) complexes are presented that survey two electronic donor moieties (phenolate and carbazolate) and three electronic acceptors (pyridine, pyrimidine, and pyrazine). A unique ligand based on an o-terphenyl motif forms an eight-membered chelate, which enhances through-space charge-transfer (CT) interactions by limiting through-bond conjugation between the donor and acceptor. A single isomeric product was obtained in yields up to 90%. Single-crystal X-ray diffraction structures of Zn complexes incorporating either donor show complementary interligand π–π interactions. All of the Zn complexes display long-lived luminescence in the solid state consistent with emission involving the triplet state. The phenolate-based complexes show evidence of CT emission in the solid state only with the strongest (pyrazinyl) acceptor. In contrast, all carbazolate-based complexes show evidence of thermally activated delayed fluorescence (TADF) in the solid and solution state, with photoluminescent quantum yields of up to 39%. These ligands represent a new family of Zn coordination compounds demonstrating TADF/phosphorescent properties that expand upon and elucidate design principles in the pursuit of photoactive earth-abundant metal complexes.

Understanding the ligand field interactions in lanthanide-containing magnetic molecular complexes is of paramount importance for understanding their magnetic properties, and simple models for rationalizing their effects are much desired. In this work, the equivalence between electrostatic models, which derive their results from calculating the electrostatic interaction energy of the charge density of the 4f electrons in an electrostatic potential representing the ligands, and the common quantum mechanical effective spin Hamiltonian in the space of the ground J multiplet is formulated in detail. This enables the construction of an electrostatic potential for any given ligand field Hamiltonian and discusses the effects of the ligand field interactions in terms of an interaction of a generalized 4f charge density with the electrostatic potential. Such models often allow for an easier rationalization of the ligand field interactions, and it can be hoped that the results in this work will help us to better understand the effects of ligand field in lanthanide complexes.

A series of Co^III complexes [Co(^RImP)₂][PF₆], with H^MeImP = 1,1′-(1,3-phenylene)bis(3-methyl-1-imidazole-2-ylidene)) and R = Me, Et, iPr, nBu, is presented in this work. The influence of the strong donor ligand on the ground and excited-state photophysical properties was investigated in the context of different alkyl substituents at the imidazole nitrogen. X-ray diffraction revealed no significant alterations of the structures and all differences in the series emerge from the electronic structures. These were probed via cyclic voltammetry and UV–vis spectroscopy, detailing the influence of the different alkyl substituents on the ground-state properties. All complexes are emissive at 77 K from a ³MC state, which exhibits lifetimes in the range of 1–5 ns at room temperature, depending on the alkyl substituent. Therefore, it is clearly shown that even small differences in the electronic structure have a large impact on the details of the excited state landscape. The observed behavior was rationalized by a detailed DFT analysis, which shows that the minimum-energy crossing point to the ground-state is located only slightly above the MC energy: Consequently, nonradiative decay to the ground state at room temperature is enabled, while at 77 K this path is prohibited, leading to low-temperature ³MC emission.