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Low-cost and high-efficiency catalysts are of crucial importance for the electrocatalytic hydrogen evolution reaction (HER). Two-dimensional (2D) boron nitride (B–N) compounds formed by the combination of boron and nitrogen atoms of group III and V elements are promising candidates for electrocatalytic HER due to their significant electronic properties. Hence, an electrocatalyst is computer-aided designed with isolated single atoms of 3d, 4d, and 5d transition metals supported on 2D B–N (B2N, B5N3, and B7N5) monolayers to fabricate single-atom catalysts (SACs) with an excellent HER performance. Moreover, pH modulations are considered to improve the HER activity theoretically based on first-principles calculation. Our results indicate that B–N compounds surface doping with transition metal atoms can effectively enhance the HER catalytic performance over a wide range of pH. Among all SACs studied, Co-, Ti-, V-, Nb-, Ru-, Tc-, Zr-, and Os-embedded B2N, Sc-, Cr-, Mn-, Ti-, and Y-embedded B5N3, and Sc- and Mn-embedded B7N5 have excellent catalytic activity under acidic conditions, while Mo-, Ir-, Re-, Ta-, and W-embedded B2N and Ti- and Fe-embedded B7N5 show high catalytic activity under alkaline conditions. Interestingly, Hf@B2N and V@B5N3 systems exhibit promising catalytic activity under acidic, neutral, and alkaline conditions. Our work offers cost-effective candidates with a wide pH range HER performance for exploring ideal electrocatalysts. [ABSTRACT FROM AUTHOR]

Heterojunction catalysts in the field of hydrogen evolution reaction (HER) from electrocatalytic water splitting have recently become a hot research topic. In this paper, we systematically calculated the HER catalytic performance of a MoS2/CoS2 heterojunction for the first time, considering the effect of edge sites regulation, strain and electric field. The results indicate that the MoS2/CoS2 heterojunction exhibits synergistic catalytic performance compared to MoS2 and CoS2, the HER catalytic activity of which can be improved by exposing more edge sites or regulating the S content on the edges, with an optimized ratio of 25%. Surprisingly, applying strain has a slight effect on the catalytic activity of the edge, however, an obvious effect on the basal plane. For example, applying 2% tensile strain on the MoS2/CoS2 heterojunction can improve the edge catalytic performance by 13%, and for the basal plane, this value can reach 92%. In this case, the catalytic performance of the basal plane is better than that of the edge with 2% and without strain. Since the basal plane accounts for the majority of the two-dimensional catalysts, the catalytic performance of the basal plane is generally much lower than that of the edge. This discovery is of great significance, which means by adjusting strain, the catalytic performance of the heterojunction catalyst is likely to be improved by orders of magnitude. Moreover, considering the actual experimental process, we also calculated the effect of the electric field and found that 0.7 V/Å electric field can enhance the HER catalytic activity of the MoS2/CoS2 heterojunction by 23%. [ABSTRACT FROM AUTHOR]

The development of robust and efficient photocatalytic constructs for boosting the water oxidation reaction (WOR) is needed for establishing a sunlight-driven renewable energy infrastructure. Here, we synthesized plasmonic core–shell nanoconstructs consisting of triangular gold nanoprism (AuTNP) core with mixed manganese oxide (MnOx) shell for photoelectrocatalytic WOR. These constructs show electrocatalytic WOR with a low onset overpotential requirement of 270 mV at pH 10. Photoexcitation showed further enhancement of their catalytic activity resulting in ∼15% decrease of the onset overpotential requirement along with the generation of photocurrent density of up to 300 μA/cm2. We showed that such light-driven enhancement of AuTNP@MnOx dyad's catalytic activity toward the WOR process includes contributions from both photocatalytic (hot carriers driven) and photothermal effects with photothermal effect playing the major role for wavelength between 532 and 808 nm. The contribution from the photocatalytic effect is appreciable only for high-energy excitations near the interband region, while the photothermal effect largely dominates for lower energy excitations near the LSPR wavelengths of the dyad. [ABSTRACT FROM AUTHOR]

Classical theories of enzyme inhibition kinetics predict a monotonic decrease in the mean catalytic activity with the increase in inhibitor concentration. The steady-state result, derived from deterministic mass action kinetics, ignores molecular noise in enzyme-inhibition mechanisms. Here, we present a stochastic generalization of enzyme inhibition kinetics to mesoscopic enzyme concentrations by systematically accounting for molecular noise in competitive and uncompetitive mechanisms of enzyme inhibition. Our work reveals an activator-inhibitor duality as a non-classical effect in the transient regime in which inhibitors tend to enhance enzymatic activity. We introduce statistical measures that quantify this counterintuitive response through the stochastic analog of the Lineweaver–Burk plot that shows a merging of the inhibitor-dependent velocity with the Michaelis–Menten velocity. The statistical measures of mean and temporal fluctuations - fractional enzyme activity and waiting time correlations - show a non-monotonic rise with the increase in inhibitors before subsiding to their baseline value. The inhibitor and substrate dependence of the fractional enzyme activity yields kinetic phase diagrams for non-classical activator-inhibitor duality. Our work links this duality to a molecular memory effect in the transient regime, arising from positive correlations between consecutive product turnover times. The vanishing of memory in the steady state recovers all the classical results. [ABSTRACT FROM AUTHOR]

A series of bridging linkers such as pyrazine (L1), 4,4′-bipyridine (L2), (E)-1,2-di(pyridin-4-yl)ethene (L3), 1,2-di(pyridin-4-yl)ethane (L4), 1,2-di(pyridin-4-yl)disulfane (L5), 1,2-di(pyridin-4-yl)diazene (L6) and 1,4-di(pyridin-4-yl)benzene (L7) has been used in a Cu(II)-mediated cyano group activation in sodium 2-(2-(dicyanomethylene)hydrazineyl)benzenesulfonate (NaHL), leading to [{Cu(H2O)(La)}2(μ-L1)]n (1) (La = (Z)-2-(1-cyano-2-imino-2-methoxyethylidene)-1-(2-sulfonatophenyl)hydrazin-1-ide), [{Cu(H2O)(La)}2(μ-L2)]·2H2O (2), [{Cu(X)(La)}2(μ-L3)]·3H2O (3) (X = H2O or CH3OH for the two independent units), [{Cu(CH3OH)(La)}2(μ-L4)]·2H2O (4), [{Cu(La)}2(μ-L5)2]n (5), [{Cu(μ-La)}2(μ-L6)Cu(H2O)(La)]2·4H2O (6) and [{Cu(H2O)(La)}2(μ-L7)] (7), respectively. Depending on the length of the respective linkers, the distance between the two copper(II) centres in 1–7 can be expanded/adjusted from 6.762 to 15.138 Å. The catalytic activity of the synthesized compounds in the cyanosilylation reaction of aldehydes with trimethylsilyl cyanide in methanol was performed. No linear correlation among the length of the bridging ligands and the yield of 2-phenyl-2-((trimethylsilyl)oxy)acetonitrile was observed in 1–7 catalysed cyanosilylation of benzaldehyde with trimethylsilyl cyanide, but the copper complexes show a higher catalytic activity in comparison to the monomer [Cu(H2O)2(La)]. The higher catalytic activity exhibited by complex 5 was further investigated evaluating the effects of reaction time, catalyst amount, temperature and the activity with different aldehydes. [ABSTRACT FROM AUTHOR]

In order to overcome the often large activation barriers in heterogeneous catalytic reactions, photocatalysis is a promising path to activate specific molecules with light at moderate temperatures. In particular, bimetallic nanoparticles combining the plasmonic properties of one metal with the high catalytic activity of another are promising antenna–reactor systems. As the nanocrystal surface structure is a major factor in steering surface electronic properties and accompanying activity and selectivity, it is of interest to control the metal nanoparticle growth and composition. The subject of this work is the synthesis of gold–platinum nanoparticles with varying architectures by controlling the growth mechanism. The selection of the reducing agent allows the regulation of the reduction rate of the platinum metal salt, which in turn affects the final morphology of the resulting bimetallic nanoparticles. This allows the synthesis of either core–shell nanocrystals with decorated nanocube corners or dendritic particles under otherwise identical reaction conditions. A dendritic structure requires the rapid deposition of platinum monomers on the surface of the gold particles. This process hinders the diffusion of platinum monomers to energetically preferred sites on the particle surface, which is possible during the formation of core–shell nanocrystals. [ABSTRACT FROM AUTHOR]

A simple, green, and scalable approach, utilizing dielectric barrier discharge (DBD) plasma in lieu of chemical reductants, is presented for producing Pt/C catalysts. The results revealed crystalline well-dispersed Pt nanoparticles of small sizes were generated on the surface of carbon support, where the Pt loading can be regulated by adjusting the H2PtCl6 concentration. The resulting Pt/C catalysts demonstrated excellent catalytic activity in both acidic and alkaline electrolytes for hydrogen evolution reactions (HER) and methanol oxidation reactions (MOR). With the rise of the Pt loading, the catalytic activity gradually improves. Specifically, for HER, an overpotential value of 120 mV was measured for the 8 wt% Pt/C-modified electrode at a geometric current density of −10 mA cm−2, with a Tafel slope of 45.4 mV dec−1 in acidic electrolyte. The values became 208 mV and 83.7 mV dec−1 in alkaline electrolyte. Same phenomenon was also observed in MOR, where the increase of the Pt loading results in faster electron transport rate and stronger methanol oxidation peak. Besides, the catalytic activity of the plasma-prepared Pt/C catalysts is better than the commercial samples with the same Pt loading. This work demonstrates a DBD plasma-assisted strategy for the preparation of Pt/C catalysts in an efficient and environmentally friendly manner. [ABSTRACT FROM AUTHOR]

The development of an effective catalytic system for the dehydrogenative coupling of hydrosilanes with alcohols remains an ongoing challenge, particularly for alcohol protection applications. In this study, we report the development and optimization of a highly efficient gold catalyst supported on fibrillated cellulose modified with citric acid. The catalyst exhibited remarkable catalytic activity under mild conditions with 0.01–0.05 mol% of Au loading, facilitating the formation of silyl ethers with excellent yield. Notably, our catalytic system overcomes the need for excess alcohol, typically required in such reactions, making it highly practical for alcohol protection applications. This work represents a significant advancement in the field of dehydrosilylation catalysis, offering a sustainable, efficient, and environmentally friendly approach for the synthesis of functional silanol-based materials and alcohol protection applications. The scope of substrates and the utility of the catalyst have been thoroughly studied. [ABSTRACT FROM AUTHOR]

Summary: Two recombinases, RAD51 and DMC1, catalyze meiotic break repair to ensure crossovers (COs) between homologous chromosomes (interhomolog) rather than between sisters (intersister). FIDGETIN‐LIKE‐1 (FIGL1) downregulates both recombinases. However, the understanding of how FIGL1 functions in meiotic repair remains limited. Here, we discover new genetic interactions of Arabidopsis thaliana FIGL1 that are important in vivo determinants of meiotic repair outcome.In figl1 mutants, compromising RAD51‐dependent repair, either through the loss of RAD51 paralogs (RAD51B or XRCC2) or RAD54 or by inhibiting RAD51 catalytic activity, results in either unrepaired breaks or meiotic CO defects. Further, XRCC2 physically interacts with FIGL1 and partially counteracts FIGL1 activity for RAD51 focus formation. Our data indicate that RAD51‐mediated repair mechanisms compensate FIGL1 dysfunction.FIGL1 is not necessary for intersister repair in dmc1 but is essential for the completion of meiotic repair in mutants such as asy1 that have impaired DMC1 functions and interhomolog bias. We show that FIGL1 attenuates interhomolog repair, and ASY1 counteracts FIGL1 to promote interhomolog recombination.Altogether, this study underlines that multiple factors can counteract FIGL1 activity to promote accurate meiotic repair. [ABSTRACT FROM AUTHOR]

• The catalytic depolymerization of PET waste was achieved at low temperature. • More than 90 % of DET and EG yields were obtained. • The response surface methodology was utilized to optimize reaction conditions. • The 3Ni-ZnO/Al 2 O 3 catalyst demonstrated excellent stability over five cycles. Plastic waste poses a serious threat to the global environment, with recycled polyethylene terephthalate (PET) plastic accounting for a considerable portion. The application of supercritical ethanol depolymerization technology presents an effective method for recycling PET waste. This study investigated using Ni as an additive to enhance the catalytic activity of ZnO/Al 2 O 3 catalyst for PET waste depolymerization. The effects of different catalysts, catalyst dosage, reaction temperature, and reaction time on PET waste depolymerization were studied using the single-factor controlled variable method. The results showed that the 3Ni-ZnO/Al 2 O 3 was the optimal catalyst, and under the optimal conditions with catalyst dosage of 4 %, reaction temperature of 260 °C, and reaction time of 60 min, the depolymerization efficiency of PET waste could reach 100 %, with the highest yields of diethyl terephthalate (DET) and ethylene glycol (EG) of 93.6 % and 90.2 %, respectively. Response surface methodology (RSM) was used to optimize the operating conditions to obtain the highest monomer yields. The predicted optimal parameters from RSM were as follows: reaction temperature = 262.8 °C, reaction time = 63.2 min, catalyst dosage = 3.8 wt%, with the predicted highest DET and EG yields of 95.9 % and 90.7 %, respectively. The analysis of variance (ANOVA) results for DET and EG possessed the R2 values of 0.9921 and 0.9885, respectively, with p-values < 0.0001, indicating a good fit for the models. Furthermore, after five times reuse, the 3Ni-ZnO/Al 2 O 3 catalyst still exhibited good catalytic activity and stability. In conclusion, this study offers a clean, green, and sustainable alternative to recycling plastic waste. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Electron transfer is an important way to activate persulfate. Currently, the electrons for persulfate activation mainly originate from organic contaminants or the catalyst itself, which can lead to selective activation of persulfate or oxidation of the catalyst, respectively, and thus become a bottleneck restricting its application. In this work, Cu−doped FeVO4 (Cu−FVO) was prepared, and the results showed that Cu doping can significantly improve the photocatalytic activity and stability of FVO for peroxymonosulfate (PMS) activation. The optimized Cu−FVO/PMS/light system exhibited a high BPA degradation rate that is 4.3 times higher than that of the FVO/PMS/light. This system manifested a broad applicability to various organic contaminants even with complex matrix. Photoelectrochemical analysis and DFT theoretical calculations revealed that Cu doping boosted the photogenerated charge separation and the adsorption of PMS on FVO. Furthermore, Cu doping led to the establishment of an electron transfer channel from Cu−FVO to PMS, through which photogenerated electrons achieved an efficient PMS activation. Meanwhile, holes were consumed by organic contaminants to avoid the oxidation of catalyst. These collectively enhanced the photocatalytic activity and stability of Cu−FVO, which also maintained high catalytic activity even after 20 cycling degradation reactions. [ABSTRACT FROM AUTHOR]

The synthesis of biologically active benzoxanthene, and bis(3-hydroxy-5,5'-dimethyl-2-cyclohexene-1-ones) derivatives has been conducted under an environmentally benign method by using an efficient catalyst, silica-tungstosulphonic acid. The benefits of this catalyst include being safe for the environment, low-cost, and simple to construct. It produces good yields and high purity in a short time and facilitates easy cleansing, products are obtained by straightforward recrystallization without the need for column chromatography. The reagent retained its catalytic activity for at least five consecutive cycles of reuse. The catalyst is described by IR, XRD, and SEM-EDX, which clearly shows that sulfonation happens in silica tungstic acid. In addition, the targeted derivatives were studied for anti-oxidant properties such as DPPH, reducing power assay, and H2O2 scavenging activity. The synthesized products such as 3e, 5k, 5 m, 5o, and 5p showed good anti-oxidant properties. Among all of these compounds, 5p showed good activity due to the nitro substitution on the benzene ring. [ABSTRACT FROM AUTHOR]

This study was focused on the design and development of a new heterogeneous catalyst based on polyester (PE) fabric modified with graphene oxide nanosheets decorated with silver metallic nanoparticles (PE-rGO/Ag0), using a simple, easy, and effective approach. PE fabrics were coated by sonication with graphene oxide (GO) nanosheets followed by in situ deposition and reduction of silver nanoparticles over the GO surface, covering the PE fabric and producing PE-rGO/Ag0. The crystalline structure, surface morphology and chemical characteristics of the synthesised materials were identified by X-ray diffraction spectroscopy, scanning and transmission electron microscopy analyses (SEM and TEM) and by Fourier-transform infrared spectroscopy (FTIR), respectively. The catalytic performance of the prepared PE-rGO/Ag0 was assessed during the hydrogenation of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) in the presence of sodium borohydride (NaBH4). Experimental results indicate that PE-rGO/Ag0 with a surface of 6 cm2 (3x2 cm) showed the highest catalytic activity with an apparent reaction rate constant (Kapp) of 0.65 min−1. In addition, PE-rGO/Ag0 activity resulted to be comparable and significantly higher than previously reported values of silver-based catalysts. Remarkable stability values were achieved during different operating cycles without significant degradation in the catalytic activity, suggesting that PE-rGO/Ag0 can be used as a strong candidate in long-lasting chemical catalytic processes. [ABSTRACT FROM AUTHOR]

[Display omitted] • Derived from Ti 3 C 2 T x , TiO 2 acts as a carrier, effectively avoiding agglomeration. • The generation rate of H 2 under light reaches 496 mmol g−1 h−1. • This provides a new idea for solar photothermal conversion. Methane dry reforming (DRM) can consume greenhouse gases (CH 4 and CO 2) to produce valuable Fischer-Tropsch syngas (CO and H 2). However, conventional thermally driven DRM consume large amounts of energy and face problems such as catalyst sintering and carbon deposition leading to insufficient catalytic activity. In this study, a photothermal synergistic TiO 2 /CeO 2 /Ru catalyst with high efficiency was designed. Under the light condition, the yields of H 2 and CO reached 496.3 mmol g−1 h−1 and 522.4 mmol g−1 h−1, respectively. In addition, the catalyst demonstrated excellent stability after 100 h cyclic stability test. In-situ X-ray photoelectron spectroscopy (IS-XPS) and density functional theory (DFT) calculations revealed that the heterojunction interface formed by TiO 2 /CeO 2 /Ru is favourable for capturing photogenerated electrons and suppressing the recombination rate of photons and holes, thus improving the photocatalytic performance. Furthermore, light-induced metal-to-metal charge transfer (MMCT) accelerated oxygen migration, which not only improved the catalytic activity, but also suppressed the formation of carbon deposits on the catalyst surface, thereby enhancing the cycling stability. This study explores the mechanism of photothermally synergistic DRM, which provides a new pathway for the efficient use of solar energy. [ABSTRACT FROM AUTHOR]

A synergism between CoMo and Fe 2 O 3 dominating the prominent HER and OER performance is demonstrated. [Display omitted] • Novel CoMo/Fe 2 O 3 /NF nanoarchitecture is designed for overall water splitting. • The optimized CoMo/Fe 2 O 3 /NF exhibits outstanding HER and OER catalytic activity. • The constructed overall water-splitting cell attains 10mA cm−2 at 1.5 V. • The synergistic effect between multiple metals dominates the high catalytic activity. Constructing bifunctional non-precious metal electrocatalysts with advanced industrial value and excellent electrocatalytic performance to achieve efficient overall water splitting is important but difficult. Herein, a heterogeneous electrocatalyst comprising of CoMo alloys anchored Fe 2 O 3 nanosheets was prepared by hydrothermal and electrodeposition methods. The strongly coupled interfaces between the CoMo alloys and Fe 2 O 3 nanosheets promote charge redistribution, which could improve electron transfer efficiency and accelerate reaction kinetics, potentially optimizing reactant adsorption energy. Further density functional theory (DFT) calculations reveal that the construction of CoMo/Fe 2 O 3 /NF heterostructured catalyst facilitates to promote interfacial charge redistribution and enhance charge transfer capacity, thus boosting the catalytic performance. Benefiting from this, the optimal CoMo/Fe 2 O 3 /NF heterostructure demonstrates a minimal overpotential of 71 mV at 10 mA cm−2 for the HER and 266 mV at 50 mA cm−2 for the OER. Remarkably, the catalyst served as a bifunctional electrode for water splitting, resulting in a cell voltage down to 1.5 V at a current density of 10 mA cm−2. This research provides an effective way for the construction of non-precious iron oxides-based bifunctional electrocatalysts using alloy/metal oxide interfacial engineering strategy. [ABSTRACT FROM AUTHOR]

[Display omitted] Herein, it is demonstrated that 0D/2D design of zinc sulfide quantum dots encapsulated with yttrium tungstate nanosheets, which were subsequently used to increase the removal of brilliant blue (BB), methyl red (MR) dyes and doxycycline drug using UV–visible light. The produced ZnS-Y 2 WO 6 nanohybrids exhibited excellent catalytic activity, reaching degradation efficiencies of around 89.92%, 80% and 85.51 % for BB, MR dyes and doxycycline drug, respectively, with a minimum irradiation duration of 120, 60 and 125 min. These nanohybrids outperformed Y 2 WO 6 in terms of photocatalytic efficacy due to enhanced light absorption, efficient charge transfer, and decreased charge carrier recombination between ZnS and Y 2 WO 6 nanoparticles. The synergistic combination of ZnS and Y 2 WO 6 nanoparticles resulted in multiple active sites on the composite surface. Furthermore, the ZnS-Y 2 WO 6 nanohybrids maintained excellent degradation efficiencies of 79.45% and 70.12% for BB and MR dyes, respectively, even after five consecutive cycles, with no significant loss of catalytic activity. The produced ZnS-Y 2 WO 6 nanohybrids were thoroughly analyzed utilizing a variety of analytical methods. Furthermore, the degradation of organic dyes and doxycycline drug related possible mechanism were examined using experimental data, indicating the potential of ZnS-Y 2 WO 6 nanohybrids as excellent photocatalytic materials for oxidizing organic dyes and drugs in aquatic conditions. [ABSTRACT FROM AUTHOR]

P-MoO 2 @CoNiP exhibits excellent HER and UOR catalytic activities. The HER performance of the catalyst can be enhanced by the leaching and reabsorption of Mo, while the UOR performance of the catalyst is improved by the reconstruction to form NiOOH. [Display omitted] • P-MoO 2 @CoNiP has a hierarchical structure of nanosheets covering the nanorods. • The abundance of active sites on P-MoO 2 @CoNiP enhances its catalytic activity. • The leaching/reabsorption of Mo improves the HER activity of P-MoO 2 @CoNiP. • Co and P incorporation boosts NiOOH formation, enhancing the activity of UOR. • P-MoO 2 @CoNiP shows efficient bifunctional catalytic activity for HER and UOR. Combining the urea oxidation reaction (UOR) with the hydrogen evolution reaction (HER) is an effective technology for energy-saving hydrogen production. Herein, a bifunctional electrocatalyst with CoNiP nanosheet coating on P-doped MoO 2 nanorods (P-MoO 2 @CoNiP) is obtained via a two-step hydrothermal followed a phosphorization process. The catalyst demonstrates exceptional alkaline HER performance due to the formation of MoO 2 and the dissolution/absorption of Mo. Meanwhile, the inclusion of Co and P in the P-MoO 2 @CoNiP catalyst facilitated the formation of NiOOH, enhancing UOR performance. Density functional theory calculations reveal that the hydrogen adsorption Gibbs free energy (ΔG H*) of P-MoO 2 @CoNiP is closer to 0 eV than CoNiP, favoring the HER. The catalyst only needs −0.08 and 1.38 V to reach 100 mA cm−2 for catalyzing the HER and UOR, respectively. The full urea electrolysis system driven by P-MoO 2 @CoNiP requires 1.51 V to achieve 100 mA cm−2, 120 mV lower than the traditional water electrolysis. [ABSTRACT FROM AUTHOR]

Precise neighbor atomic engineering of single-atom tungsten catalysts enables boosted electrocatalytic nitrate-to-ammonia conversion. [Display omitted] • Engineered first and next-nearest neighbor coordination of W single atoms on graphene. • Identified W@C 3 exhibiting outstanding nitrate reduction activity (limiting potential −0.36 V). • W@C 3 -BN with modulated next-nearest B, N dopants achieved ultralow limiting potential (−0.26 V). • Orbital hybridization and charge effects optimize nitrate binding for enhanced activity. Nitrate contamination of water resources poses significant health and environmental risks, necessitating efficient denitrification methods that produce ammonia as a desirable product. The electrocatalytic nitrate reduction reaction (NO 3 RR) powered by renewable energy offers a promising solution, however, developing highly active and selective catalysts remains challenging. Single-atom catalysts (SACs) have shown impressive performance, but the crucial role of their coordination environment, especially the next-nearest neighbor dopant atoms, in modulating catalytic activity for NO 3 RR is underexplored. This study aims to optimize the NO 3 RR performance of tungsten (W) single atoms anchored on graphene by precisely engineering their coordination environment through first and next-nearest neighbor dopants. The stability, reaction paths, activity, and selectivity of 43 different nitrogen and boron doping configurations were systematically studied using density functional theory. The results reveal W@C 3 , with W coordinated to three carbon atoms, exhibits outstanding NO 3 RR activity with a low limiting potential of −0.36 V. Intriguingly, introducing next-nearest neighbor B and N dopants further enhances the performance, with W@C 3 -BN achieving a lower limiting potential of −0.26 V. This exceptional activity originates from optimal nitrate adsorption strengths facilitated by orbital hybridization and charge modulation effects induced by the dopants. Furthermore, high energy barriers for NO 2 and NO formation on W@C 3 and W@C 3 -BN ensure their selectivity towards NO 3 RR products. These findings provide crucial atomic-level insights into rational design strategies for high-performance single-atom NO 3 RR catalysts via coordination environment engineering. [ABSTRACT FROM AUTHOR]

[Display omitted] Hydrogen peroxide (H 2 O 2) is a crucial eco-friendly oxidizer with increasing demand due to its wide range of applications. Activating O 2 with catalysts to generate H 2 O 2 on-site offers a promising alternative to traditional production methods. Here, we design unique crystalline/amorphous heterophase Fe-Mn core–shell chains (ZVI-Mn) for efficient on-site generation of H 2 O 2 and manipulation of subsequent H 2 O 2 activation. The yield of H 2 O 2 on-site produced by ZVI-Mn in water within 5 min was 103.7 mg·L-1, which was much greater than that of zero-valent iron (ZVI) and amorphous Mn (A-Mn) (0 and 42.5 mg·L-1). Raman and density functional theory (DFT) calculations confirmed that *OOH is the key species involved in the on-site generation of H 2 O 2. Electrochemical tests confirmed the excellent electron-transferring ability, while electron paramagnetic resonance (EPR) revealed oxygen vacancy defects in the catalysts, which proved to be conducive to improving the catalytic activity of ZVI-Mn. Additionally, by regulating the pH of aqueous solution, ZVI-Mn can simultaneously achieve efficient on-site generation of H 2 O 2 and in-situ removal of enrofloxacin from aqueous solution. [ABSTRACT FROM AUTHOR]

[Display omitted] The urgent need to prepare clean energy by environmentally friendly and efficient methods, which has led to widespread attention on electrocatalytic nitrogen reduction reaction (NRR) for ammonia production. At present, single atom catalytic nitrogen reduction has become the earliest promising method for industrial production due to its high atomic utilization rate, high selectivity, high controllability, and high stability. However, how to quickly screen catalysts with high catalytic efficiency and selectivity in single-atom catalysts (SACs) remains a challenge. Herein, the 29 SACs are constructed from C 6 N 2 nanosheets doped with transition metals (TM@C 6 N 2), which are analyzed for stability, adsorption performance, NRR catalytic activity, electronic properties, and competitiveness using first-principles calculations. The results show that Mo@C 6 N 2 and Re@C 6 N 2 exhibit the most outstanding catalytic performances, with limiting potentials (U L) of −0.29 and −0.31 V, respectively, in the solvent model. Machine learning is used to derive descriptors from the intrinsic features to predict the free energy changes for the potential-determining step. The importance of features is calculated, with the first ionisation energy ( IE 1) being the most significant influencing factor. Based on the guidance of machine learning and considering that IE 1 is related to the ability of metal atoms to donate electrons, a four-step screening strategy using the Integrated Crystal Orbital Hamilton Populations (ICOHP) to screen catalysts instead of the traditional five-step screening not only improves the screening efficiency but also obtains completely consistent screening results. This work presents a new approach to predicting the catalytic performance of SACs and provides new insights into the influence of intrinsic properties on catalytic activity. [ABSTRACT FROM AUTHOR]

This abstract presents a formaldehyde catalytic mechanism diagram, illustrating the catalyst's subtle changes during the reaction process and providing a deeper understanding of its underlying mechanisms. [Display omitted] The catalytic oxidation of formaldehyde (HCHO) at ambient temperature is a highly efficient, cost-effective and environmentally friendly approach for formaldehyde removal. Reactive oxygen (O*) and reactive hydroxyl groups (OH*) are the main active species in the catalytic oxidation reaction of HCHO. Therefore, it is crucial to design catalysts that can simultaneously enhance the surface concentrations of O* and OH*, thereby improving their overall catalytic performance. The present study aimed to design an Al 2 O 3 /CoNC catalyst featuring layered carbon nitride coupled with metal oxides possessing domain-limited cobalt (Co) metal active sites, to efficiently remove HCHO (≈100 %, 100 ppm, RH=50 %, GSHV=20,000 mL/(g h)) and ensure stability (more than 90 % formaldehyde removal within 450 h) at ambient temperature. The characterization revealed that the interaction between Al 2 O 3 -supported metal and CoNC resulted in enhanced confinement of Co, leading to a higher abundance of edge structures exposing more active sites. Additionally, the presence of highly dispersed Co-N X active sites and increased oxygen vacancies effectively facilitated the adsorption and activation processes of HCHO and O 2 , as well as the adsorption and desorption dynamics of intermediates during the reaction. These factors collectively contributed to an improved catalytic activity. The results of in situ infrared spectroscopy revealed that the catalyst improved the adsorption and activation of O 2 and H 2 O, leading to the rapid generation of substantial amounts of O* and OH*. This synergistic interaction between Al 2 O 3 and CoNC plays a crucial role in the sustained production of O* and OH*, promoting efficient of intermediate decomposition, and ensuring excellent catalytic activity and stability for HCHO. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ru monoatoms are stabilized on LDH, which is proved by HAADF-STEM and XANES. • Ru@NiFe-LDH/ PMS system showed excellent degradation efficiency to SMX. • Ru@NiFe-LDH maintains its excellent catalytic activity over a wide pH range. • High-valent species (Ru(V) = O) as the main active species in PMS-based AOPs. • DFT calculations indicate the formation of Ru-PMS* complexes intermediate product. The application of single-atom catalysts (SACs) to advanced oxidation processes (AOPs) based on peroxymonosulfate (PMS) has attracted considerable attention. However, the catalytic pathways and mechanisms underlying these processes remain unclear. In this study, NiFe-LDH was synthesized and single Ru atoms were stably loaded onto it by forming Ru–O–M (M=Ni or Fe) bonds (Ru@NiFe-LDH). This was demonstrated using high-angle annular dark-field scanning TEM (HAADF-STEM) and X-ray absorption fine structure spectra (XANES). The Ru@NiFe-LDH/PMS system showed a high catalytic reactivity (100 % sulfamethoxazole degradation in only 30 min), high stability (97 % reactivity was maintained after continuous operation for 400 min), and wide pH suitability (working pH range 3–11) for AOPs. The crucial roles of the high-valent species (Ru(V) = O) and 1O 2 in this reaction were verified. Density functional theory (DFT) calculations revealed that electron transfer produced a positively charged Ru. This enhances the adsorption of negatively charged PMS anions onto the Ru monoatomic sites, thereby, causing the formation of Ru-PMS* complexes. This study implies that the structure–function relationship between organic compounds and SACs plays a significant role in PMS-based AOPs, and provides a comprehensive mechanism for the role of high-valent species in heterogeneous Fenton-like systems. [ABSTRACT FROM AUTHOR]

[Display omitted] • Co(OH) 2 acts as a template, raising the specific surface area and providing Co sites. • Altering Fe salts yields different MOF morphologies, impacting catalytic activity. • The FeCl 3 -synthesized ball-needle heterostructure shows the highest OER activity. • Mesoporous structure facilitates access to active sites and improves mass transfer. • Superaerophobic of BN-CoFe-MOF facilitates bubble release to refresh active sites. CoFe bimetallic organic frameworks (CoFe-MOFs) with tunable morphology and electronic structure are synthesized in situ utilizing cobalt hydroxide (Co(OH) 2) as a semi-sacrificial template and different anionic iron salts as modifying factors in a non-calcined synthesis method. This work defines the impact of three different anionic metallic iron salts (FeCl 3 , Fe(NO 3) 3 , and Fe 2 (SO 4) 3) on the morphology of MOF materials and their resulting oxygen evolution reaction (OER) catalytic activity. Employing ferric chloride (FeCl 3) as the metallic iron source, heterostructured electrocatalysts (BN-CoFe-MOF) with nanoparticles decorated nanoneedle tips are obtained, exhibiting a low overpotential (230 mV at 10 mA cm−2) and a Tafel slope of 105.6 mV dec−1 in 1.0 M KOH. It also demonstrates long time stability for at least 50 h at a current density of 10 mA cm−2. The investigation uncovers that the splendid OER activity and stability of the BN-CoFe-MOF heterojunction can be attributed to its large specific surface area, desirable mesoporous structure, superaerophobic characteristic, and high exposure of active centers. This work not only provides an efficient and cost-effective MOF based OER electrocatalyst but also serves as a valuable reference for future research on morphology control and strategies to enhance the OER activity of MOF catalysts. [ABSTRACT FROM AUTHOR]

To develop stable and efficient silver(I) catalysts and evaluate the role of sulfur and phosphorus donor ligands in the catalytic cycloaddition of selected organic azides and alkynes (AAC), a series of mononuclear Ag(I) and heteronuclear Ag(I)–Fe(II) complexes were synthesized. The synthesis utilized phosphine and sulfur donors from the dialkyldithiophosphate and borate families, specifically Na[S2H2B(mt)2]. These complexes are designated as [(dppf)AgSP(S)(OiPr)2] (1), [S2H2B(mt)2Ag(μ-dppf)AgS2H2B(mt)2] (2), [(dppf)Ag(μ-dppf)Ag(dppf)] (3), and [(dppe)AgS2H2B(mt)2] (5). The complexes 1–5 were characterized using a combination of 1H, 13C{1H}, and 31P{1H} NMR spectroscopy, as well as IR spectroscopy techniques. In two instances, single-crystal X-ray diffraction analysis was also employed. Complex 3 exhibited high catalytic activity and regioselectivity in the cycloaddition reaction conducted in water at 40 °C. [ABSTRACT FROM AUTHOR]

A CuI@UiO-67-bpy (MOF II) catalyst was successfully synthesized by immobilizing a small amount of CuI onto the zirconium-based MOF (UiO-67-bpy, MOF I). Copper-doped CuI@UiO-67-bpy has an isostructural nature with the parent UiO-67 framework and a large surface area of approximately 1285 m2 g−1. Moreover, the material was thoroughly characterized using SEM, PXRD, TGA, FTIR, and XPS methods. The as-synthesized CuI@UiO-67-bpy catalyst can be an efficient heterogeneous catalyst for promoting C–H arylation of 1,3,4-oxadiazoles with aryl iodides and benzoxazoles or benzothiazoles with diaryliodonium salts. Furthermore, the catalyst was recoverable and reusable, maintaining a high catalytic activity even after three cycles. The combination of the advantages of both homogeneous molecular CuI catalysts and solid MOF structures in this system may bring new opportunities for the development of highly active heterogeneous copper catalysts for a variety of Cu-catalyzed transformations. [ABSTRACT FROM AUTHOR]

Selenization of ZrO2 can be easily performed by stirring commercially available ZrO2 in an in situ prepared NaHSe solution. The produced material Se@/ZrO2 could catalyse oxidative alkene degradation reactions, which are key transformations in the industry. Control experiments confirmed that selenium loaded onto ZrO2 endowed it with good catalytic activity for oxidation reactions. In comparison with the density of other selenized catalytic materials such as Se/C, selenized silica and selenized polylactic acid, the density of Se@ZrO2 is higher. This feature makes it easy to precipitate from the reaction solution, facilitating its convenient recovery and reutilization. [ABSTRACT FROM AUTHOR]

Comprehensive Summary For coordination‐insertion olefin polymerization, the development of novel transition‐metal catalysts has drawn extensive attention in this field. In this contribution, we designed a series of hemilabile α‐diimine nickel catalysts bearing oxygen atom as neighboring group. The steric hindrance and oxygen atom number of these nickel complexes (Ni1—Ni4) could be adjusted, which influenced ethylene (co)polymerization processes. The introduction of oxygen atoms could enhance the thermal stability during ethylene polymerization for Ni2 compared to the counterpart without oxygen atoms. And for the copolymerization process of ethylene with polar monomers, higher catalytic activity (1.4 × 106 g·mol−1·h−1) and polar monomer incorporation ratio (1.2 mol%) were achieved. However, Ni4 with four oxygen atoms in this work was not active in ethylene polymerization due to the interaction between the oxygen atom and nickel catalytic center. The hemilabile effect in this work presented an example to enhance the stability of the α‐diimine nickel catalysts in olefin polymerization. [ABSTRACT FROM AUTHOR]

Developing low-cost, high-activity, and high-stability bifunctional catalysts is crucial for rechargeable zinc-air batteries but remains a significant challenge. Herein, inspired by the efficient catalysis of the oxygen reduction reaction (ORR) by main group metals (MGMs) based single-atom catalysts (SACs), we utilized first-principles calculations to explore the ORR and the Oxygen Evolution Reaction(OER) catalytic potential of 59 two-dimensional metal-containing covalent organic polymer supported MGMs based SACs under the constant charge method (CCM). The bader charge, the partial density of states (PDOS), p-band center (ε p) are utilized to study the origin of OER/ORR, and it is found that the charge transfer between metal atoms and nitrogen, as well as the ε p of oxygen after the adsorption reaction of oxygen-containing intermediates, are the main factors affecting catalytic activity. Then, we further used the constant potential method (CPM) and microkinetic simulation to verify the catalytic performance of the candidates screened by the CCM. Finally, we confirmed the outstanding catalytic activity and stability of (Sb)COF-Ppcfe (U 1/2 = 0.82 V, U = 1.65 V) and (Bi)COF-Ppcfe (U 1/2 = 0.86 V, U = 1.56 V) in neutral or alkaline environments. This work provides essential theoretical guidance for the design of more efficient and rational two-dimensional metal-containing covalent organic polymer catalysts. [Display omitted] • Integrating Constant Charge and Potential Methods. • The main group metal's p-orbitals dominate the catalytic activity. • Metal-N charge transfer and ε p of O in intermediates unveil catalytic origins. • Exceptional bifunctionality in (Sb)COF-Ppcfe and (Bi)COF-Ppcfe catalysts. • Catalyst activity relates to species distribution at different pH and potential. [ABSTRACT FROM AUTHOR]

Carbon-supported metal nanoparticles are indispensable catalysts to enabling catalytic water splitting technologies because of their unique size-dependent properties and strong metal-support interactions. Herein, we proposed a two-step synthesis strategy, using imine-type covalent organic frameworks (COFs) as a platform to synthesize nitrogen-doped carbon-supported Au with ultra-high specific surface area through the high-temperature pyrolysis. Thanks for the polarity of imine, the growth of Au NPs in Au x /NC are ultrafine, monodispersed, and the size of Au can be precisely controlled by adjusting the amount of the metal precursor during the carbothermal reaction. Such framework structure with numerous active sites provided by the COFs renders Au x /NC ultrahigh catalytic activity and durability for hydrogen evolution reaction (HER) in acid electrolyte. Most significantly, when illumination occurs, Au 5nm /NC catalyst presents a reduced HER overpotential from 416 mV to 43 mV and a shrunken charge-transfer resistance from 258 to 17 Ω, making the Au 5nm /NC a promising stable catalyst for the LSPR promoted hydrogen evolution reaction. • Au x /NC heterostructure was prepared via a two-step synthesis strategy. • The size of Au is highly tunable and precisely controlled. • This work highlights LSPR effect enhancement of noble metal catalyst on HER application. [ABSTRACT FROM AUTHOR]

Ammonia has recently attracted attention as a hydrogen carrier and fuel, based on the power-to-fuel concept. This concept can be realized using Ru-supported rare-earth oxides for the synthesis of ammonia from hydrogen and nitrogen (3H 2 + N 2 → 2NH 3) under mild conditions. However, at a high H/N ratio, Ru catalysts exhibit hydrogen poisoning, which reduces their activity for ammonia synthesis. This study investigates the effect of the H/N ratio on the ammonia synthesis activity of the developed Ru catalyst Ru(5 wt%)/Ce 0.5 La 0.4 Si 0.1 O 1.8 under isothermal conditions (350−500 °C). The optimal H/N ratio for achieving the highest catalytic activity decreases as the temperature is lowered (H/N = 0.5 at 350 °C; H/N = 2.0−2.5 at 450 °C). In a multibed reactor, adjusting the H/N ratio to a lower value in the downstream catalyst beds—where the temperature decreases along the gas flow path—can enhance the overall rate of ammonia production by optimizing the reaction conditions in these cooler stages. We propose a system to control the H/N ratio for each catalyst bed in a multibed reactor and demonstrate an increase in the rate of ammonia production when using a double-bed reactor containing the Ru/Ce 0.5 La 0.4 Si 0.1 O 1.8 catalyst. The proposed system offers various opportunities to accelerate the use of ammonia as a hydrogen carrier and fuel. [Display omitted] • An NH 3 synthesis system tailored to the properties of Ru catalysts is proposed. • The developed Ru catalyst is used to demonstrate the effectiveness of this system. • The H/N ratio at which the catalyst exhibits the highest activity shifts toward a lower value at lower temperatures. • A double-bed reactor that enables H/N ratio control in both beds is developed. • The total NH 3 production rate in the reactor is enhanced by H/N ratio control. [ABSTRACT FROM AUTHOR]

The development of photocatalytic materials with good adsorption capacity and high visible light activity is essential for efficient and stable photocatalytic hydrogen production from formic acid dehydrogenation. The wide band gap of TiO 2 photocatalyst materials limits their application in the field of visible light catalysis. In this work, a new composite material, Pd/CQDs/TiO 2 –NH 2 , is developed. Here, Pd is attached to amine-functionalized mesoporous titanium dioxide modified with carbon quantum dots (CQDs). This configuration is designed to enhance the catalytic activity for formic acid dehydrogenation when exposed to visible light. The Pd/CQDs-1/TiO 2 –NH 2 catalyst exhibited outstanding performance under visible light, achieving a turnover frequency (TOF) of 2666.1 h−1 at 308 K and perfect hydrogen selectivity. Compared to the Pd/TiO 2 –NH 2 catalyst with a TOF of 1715.5 h−1, this is a significant improvement. The data implies that the addition of CQDs significantly increases light efficiency, aids in the separation of photogenerated charge carriers, and enhances hydrogen production. Ultimately, the experiments clarified how the combined action of Pd, CQDs, and TiO 2 –NH 2 synergistically boosts the catalytic dehydrogenation of formic acid under visible light. The findings present an innovative approach to improving Pd/TiO 2 schottky materials. • Ultrafine Pd nanoparticles were immobilized on CQDs/TiO 2 –NH 2. • Pd/CQDs-1/TiO 2 –NH 2 catalyst showed the best photocatalytic FA dehydrogenation under full-spectrum light. • The superior photocatalytic activity is due to the introduction of CQDs and the Mott-Schottky effect. [ABSTRACT FROM AUTHOR]

The production of hydrogen from directly catalytic ammonia decomposition shows promise in improving the ammonia viability for engine use. For practical application, it is demanded to investigate additives as well as their impact mechanism on the catalytic properties of transition metal catalysts. Herein, a series of Co/CeO 2 catalysts were prepared via a facile precipitation method and the effect of Mg adding was investigated. It is found that addition of 1% Mg decreased the catalytic activity of 5% and 10% Co/CeO 2 , while increased that of 20% Co/CeO 2. Systematic characterizations revealed that Mg promoted the metal-support interaction, which not only benefited the dispersion of Co, but also increased the valence state of Co and enhanced the reducibility. Also, more oxygen vacancies were generated, thus benefiting the reaction process. This work invested new insights into the role of alkaline-earth metal in NH 3 decomposition and provided a strategy to modulate the hydrogen–ammonia ratio which is vital for NH 3 combustion. [Display omitted] • Mg addition decreased the catalytic activity of 5 % and 10 % Co/CeO 2 , while improved that of 20 % Co/CeO 2. • Mg promoted the dispersion of Co over 20 % Co/CeO 2. • Mg increased the valence state of Co and enhanced the reducibility of 20 % Co/CeO 2 via strengthening the metal-support interaction. • Mg generated more oxygen vacancies over 20 % Co/CeO 2 , which benefited the reaction. [ABSTRACT FROM AUTHOR]

Developing cost-effective and high-performance electrocatalysts is crucial for overcoming the slow oxygen evolution reaction (OER) observed in the process of water splitting. Herein, an exquisite iron-cobalt bimetallic sulfide featuring exposing more crystal faces and stronger crystallinity is manipulated via a mechanical stress strategy, which may offer additional active sites for the OER process. Particularly, the prepared Fe 0.5 Co 0.5 /SNC exhibits notable OER activity, characterized by a low overpotential of 310 mV at a current density of 10 mA cm−2 and a high current density of 131 mA/cm2 at a voltage of 1.8 V (versus RHE). Additionally, post-stability tests analysis on the material revealed a reversible oscillation of iron and cobalt valence states between 2+ and 3+, indicating the material's sensitivity to reactive oxygen species, which enhances its OER catalytic performance. The continuous adsorption and desorption of reaction intermediates with the material's matrix perpetually trigger the activation, maintaining the catalytic activity. Theoretical calculations suggest that orbital hybridization among iron, cobalt, and sulfur, along with an appropriate d-band center, enhance the electron exchange rate, facilitating the adsorption and dissociation of intermediates on the material, thereby promoting the OER process. Our findings provide new insights for the design and production of efficient, cost-effective OER electrocatalysts, contributing to the industrialization of OER catalysts. • Developed a new method combining hard template and mechanical stress for synthesis. • Crystallinity of iron-cobalt sulfide is 14.53 times higher than hydrothermal method. • Polyhedron exposes more active sites, enhancing OER activity with 310 mV overpotential. • Turnover frequency reaches 0.013 s-1, 2.6 times higher than IrO2's 0.005 s-1. • DOS and d-band center reveal the reaction mechanism of efficient catalysts. [ABSTRACT FROM AUTHOR]

Noble metal-free catalysts have recently attracted much attention towards overall electrochemical water splitting. However, poor kinetics of the reactions, involved in water splitting leads to lower hydrogen production in alkaline electrolytes. Hence, it is essential to design highly active, conductive and cost-efficient catalysts for water electrolysis. Therefore, a bifunctional electrocatalyst based on cobalt oxide (CoO) incorporated over nickel selenide (NiSe 2) supported on nickel foam (CoO/NiSe 2 /NF) was synthesized via a two-step process involving hydrothermal and electrochemical deposition methods. The synthesized material was characterized thoroughly using XRD, XPS, SEM and FE-SEM. After thorough characterization, all the synthesized materials were employed as electrocatalysts towards overall water splitting. The electrochemical studies revealed that CoO/NiSe 2 /NF has demonstrated excellent electrocatalytic activity towards overall electrochemical water splitting. The improved electrochemical activity of nano-hybrid could be attributed to heterogeneous structure, enhanced edge sites and the synergetic cooperation of CoO and NiSe 2. Finally, two electrode setups were prepared to perform overall water electrolysis in which CoO/NiSe 2 /NF need a cell potential of 2.03 V to attain 100 mA cm−2. The study proposes an approach for heterogeneous structure engineering to boost the catalytic performance of noble metal-free materials. [Display omitted] • CoO/NiSe 2 /NF nanohybrid synthesized hydrothermally and electrochemical deposition method. • All synthesized materials were utilized as bifunctional catalysts for overall water splitting. • Interface engineering of CoO and NiSe 2 significantly boosts electrocatalytic activity. • Abundant active sites were obtained by Interface engineering. • CoO/NiSe 2 /NF demonstrated higher activity and stability towards overall water splitting. [ABSTRACT FROM AUTHOR]

This research focused on the production of hydrogen (H 2) from formic acid (FA) using palladium nanoparticles, promoted by zirconium, on amine-functionalized RUB-15. The 2%Pd-0.2%ZrO 2 /RUB-15-NH 2 catalyst was produced through a hydrothermal technique and its physicochemical properties were characterized using various analyses including XRD, FTIR, BET, FE-SEM, TEM, EDS-dot mapping, CO 2 -TPD, and TGA. These nanoparticles were successfully created with a small size of 3.75 nm and appropriate dispersions. Zirconium oxide (ZrO 2) induced significant electronic effects between Pd and RUB-15-NH 2 and strong interaction between Pd–ZrO 2 nanoparticles and RUB-15-NH 2. The dehydrogenation process with sodium formate (SF) additive was carried out at three different temperatures in a double-necked balloon under FA/SF = 1:1 condition. Overall, 2%Pd-0.2%ZrO 2 /RUB-15-NH 2 exhibited satisfactory catalytic activity, 100% H 2 selectivity, no detectable CO production, and good reusability for H 2 production from FA. When SF was added to an FA aqueous solution for dehydrogenation, the total turnover frequency (TOF total) and the initial TOF (TOF initial) could reach 99.54 mol CO2+H2 mol pd −1 h−1 and 140 mol CO2+H2 mol pd −1 h−1 at 333 K, respectively. The stability test was measured in three cycles and showed great resistancy and activity during 140 min. The kinetic study was discussed and the first-order equation had a suitable result. Generally, the system's selectivity, high activity, stability, and simplicity in producing H 2 /CO 2 gas without CO production from FA were the key features of this catalyst. [Display omitted] • Amine-functionalized RUB-15 was used as a catalyst support in formic acid dehydrogenation. • 2%Pd-0.2%ZrO 2 /RUB-15-NH 2 showed high catalytic activity in formic acid dehydrogenation with TOF initial of 140 mol CO2+H2 mol pd −1 h−1. • The selectivity of hydrogen production was 100% without producing any contaminants. • Kinetic study was carried out using the linear and Arrhenius model. [ABSTRACT FROM AUTHOR]

Nickel selenide (NiSe) and carbon nanotubes (CNTs) heterojunction structure water electrolysis catalyst was prepared by vapor deposition method, constructing a heterogeneous phase interface between NiSe and CNTs. The interface effect between NiSe and CNTs enhanced further π-electron delocalization of CNTs, increasing the local electron density at the Ni sites. Subsequent ionic liquids (ILs) treatment further resolved the aggregation issues of NiSe nanoparticles and carbon nanotubes, and facilitated further π-electron delocalization at the heterojunction. The imidazolium cations acted as "connectors," tightly linking the CNTs and NiSe nanoparticles. The NiSe/CNT-IL exhibited an HER overpotential of 82 mV at 10 mA cm⁻2 in 1 M KOH. Additionally, as a full water electrolysis catalyst in a water electrolyzer, it achieved a single-cell voltage of 1.965 V at a maximum current density of 500 mA cm⁻2 at 60 °C. This direct IL functionalization for CNTs facilitates the electron transfer process and ILs can serve as the electron acceptor with superior hydrogen adsorption. • The delocalization of electrons in the carbon nanotubes is enhanced, increasing the electron density near the Ni sites. • The ionic liquid improves the dispersion of carbon nanotubes. • The ionic liquid coats the catalyst surface, stabilizing catalyst particles and enhancing catalytic activity and selectivity. • The hydrophilicity of the catalyst is improved. [ABSTRACT FROM AUTHOR]

Chemical (ion exchange resin) and biomass (water hyacinth leaves) as carbon precursors are adopted to prepare two kinds of bimetallic carbide (Fe 2 MoC)-based catalytic materials. It is found that, compared with the material that use ion-exchange resin as carbon precursor (N–Fe 2 MoC-RG), the material that use water hyacinth as carbon precursor (N–Fe 2 MoC-WHG) has more advantages in cost, environment protection, synthesis simplicity, and catalytic activity for oxygen reduction reaction (ORR). Therein, the N–Fe 2 MoC-WHG as a cathode catalyst displays a half-wave potential of 0.905 V (vs. RHE) for catalyzing ORR in alkaline media, and gets a high peak power density of 1.52 W cm−2 in alkaline electrolyte membrane fuel cell; moreover, the N–Fe 2 MoC-WHG displays higher power-density retention or growth rate at lower relative humidity, higher back pressure, higher working temperature and higher catalyst loading, compared with the N–Fe 2 MoC-RG. The N–Fe 2 MoC-WHG is one of the most active precious metal-free catalysts reported so far, and its stability is very excellent. [Display omitted] • Green process can synthesize Fe 2 MoC at lower temperatures. • Fe 2 MoC by Green process is more active in ORR than traditional process. • Green process obtained Fe 2 MoC is highly stable, costs low, and emits no pollution. [ABSTRACT FROM AUTHOR]

Designing a highly effective bifunctional electrocatalysts for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is a sensible approach for generating enormous hydrogen fuel by electrochemical water splitting. Herein, a high performance of ZIF-derived Co 3 S 4 on WS 2 -WO 3 electrocatalyst was developed for overall water splitting reactions. For developing the mixed phase of WS 2 -WO 3 , thioacetamide (TAA) played a crucial role as a sulfur source and acted as intercalating agent for expanding the layers of 1T WS 2 via the possible generation of NH 4 + ion. The high electrocatalytic performances is attained by the homogeneous incorporation and tunable properties of nano-sized Co 3 S 4 on WS 2 -WO 3. The electrocatalyst showed remarkable HER performance with an overpotential of only 73 mV and good OER efficiency with an overpotential of 307 mV at 10 mA/cm2. The long term chronopotentiometry and CV cycles performances convinces the stability of the electrocatalysts. A reasonable two-electrode overall water splitting performance was achieved by the WS 2 -WO 3 /Co 3 S 4 electrocatalyst in an asymmetric device, paving the path for more developments in the design and optimization of electrocatalysts for renewable energy conversion. [Display omitted] • A new kind of bifunctional electrocatalyst of ZIF-derived Co 3 S 4 on WS 2 -WO 3. • Ammonium ion intercalation promotes in increased 1T WS 2 layers. • Heterostructure interface between WS 2 -WO 3 and Co 3 S 4 expands catalytic activity. • WS 2 -WO 3 /Co 3 S 4 electrocatalyst provides excellence in HER activity. [ABSTRACT FROM AUTHOR]

The metastable phase molybdenum carbide-based (α-MoC 1-x) catalysts stand out as a class of the most promising representatives among the non-sulfide catalysts for the synthesis of higher alcohols (HAS) from syngas (CO/H 2) due to their noble metal-like characteristics, resistance to coking, sulfur tolerance and weak C–O bond dissociation. However, the synthesis of α-MoC 1-x commonly involves temperature-programmed ammonification and carburization (TPAC) or the consumption of noble metals. The α-MoC 1-x prepared by TPAC usually exhibited large particle size, low dispersion and poor catalytic performance. Herein, we developed a facile and continuous thermal plasma method for synthesizing nanosized α-MoC 1-x , which was highly dispersed on amorphous carbon (α-MoC 1-x /C-Pla). Compared with the α-MoC 1-x prepared by TPAC method (α-MoC 1-x -TPAC), the α-MoC 1-x /C-Pla catalyst exhibited higher CO conversion and excellent stability. The high dispersion and reactant adsorption/desorption capacity of α-MoC 1-x /C-Pla contributed to its high catalytic activity, while the anti-aggregation property of the nanosized α-MoC 1-x in α-MoC 1-x /C-Pla conferred the high stability for the α-MoC 1-x /C-Pla catalyst. [Display omitted] • A facile and continuous method for synthesizing α-MoC 1−x /C-Pla was developed. • Nanosized α-MoC 1−x particles were well dispersed on carbon in α-MoC 1−x /C-Pla. • α-MoC 1−x /C-Pla exhibited high activity and stability for syngas to higher alcohols. [ABSTRACT FROM AUTHOR]

The rapid detection and early warning of H 2 leakage at relatively low temperatures are crucial for ensuring the safety of human life and property. Tungsten trioxide (WO 3) nanocubes are promising gas-sensing materials due to their relatively large surface area, high activity, and low cost. However, the application of pure WO 3 nanocube for hydrogen (H 2) detection is limited by poor sensing properties, such as low response and high operating temperature. In this study, we synthesized WO 3 nanocubes decorated with varying amounts of platinum oxide (PtO) through an impregnation route followed by calcination. The optimized PtO-WO 3 sensor exhibited a high response value of 340 and an ultrafast response time of 1 s–100 ppm H 2 at the optimum operating temperature of 200 °C. Additionally, the sensor demonstrated a low detection limit of 123 parts per billion (ppb) for H 2 and exhibited excellent repeatability, selectivity, and long-term stability. The enhanced gas sensing performance can be attributed to the synergistic effects of the heterostructure between PtO and WO 3 , and the catalytic activity of PtO as well as platinum (Pt). The PtO-WO 3 sensor shows great potential for practical applications in detecting H 2 in air. • PtO-decorated WO 3 nanocubes were successfully prepared. • The PtO-WO 3 sensor demonstrates an ultrafast response time of 1 s towards 100 ppm H 2. • The PtO-WO 3 sensor has an experimentally determined detection limit of 500 ppb. [ABSTRACT FROM AUTHOR]

The development of bifunctional electrocatalysts with high efficiency for overall water splitting is still a challenging task. In this work, we introduce a novel one-step synthesis method for Pt/NiFe layered double hydroxide (LDH) on an iron-nickel foam (INF) substrate under mild conditions. This method eliminates the need for additional Ni or Fe ions and facilitates in-situ etching and growth processes under mild conditions, resulting in a higher active surface area, well-dispersed low-loading Pt nanoparticles, and a self-supported electrode without binders. These features collectively enhance electron transfer and catalytic activity for both HER and OER. The Pt/NiFe LDH/INF exhibits remarkable water splitting performance, requiring a cell voltage of only 1.44 V at10 mA cm−2 when used as both anode and cathode. Additionally, it remains stable at 20 mA cm−2 for at least 16 h. The exceptional water splitting activity of Pt/NiFe LDH/INF in alkaline solution can be attributed to the synergistic effects of Pt and NiFe LDH, which improve the hydrogen evolution reaction and oxygen evolution reaction efficiencies. The results provide valuable insights into designing bifunctional electrocatalysts with low Pt loading for optimal water splitting performance at low operating cost. [Display omitted] • Novel one-step synthesis of bifunctional Pt/NiFe LDH electrocatalyst under mild conditions. • Excellent bifunctional HER and OER activity of the Pt/NiFe LDH/INF catalyst. • Water splitting cell voltage of 1.44 V at 10 mA cm−2 with good stability. • Enhanced water splitting performance of the low-loading Pt with NiFe LDH. [ABSTRACT FROM AUTHOR]

Renewable energy sources are crucial for addressing the energy crisis and global warming, but their intermittent nature necessitates storage. Metal–air batteries, such as Li–air batteries, offer high specific capacity and environmental friendliness but face issues like poor reaction kinetics and high overpotential during charging and discharging. To address these issues, noble metal-based catalysts have been utilized, which require the replacement of such precious and scarce resources with affordable and commercially accessible materials. Biomass, a renewable resource, plays a critical role in preparing carbon-based electrocatalysts and porous cathodes with excellent performance due to its rich heteroatom and pore structure, and potential doping and co-doping with transition metals and their oxides. Metal-free biomass carbon nanostructured bifunctional electrocatalysts have been identified as potential alternatives for the next generation of oxygen reduction and evolution reactions. These catalysts have comparable catalytic activity and improved stability compared to the current state-of-the-art Pt-based catalysts, making them essential for the commercialization of lithium–air batteries. Thus, this paper reviews the most recent advances in biomass-derived metal-free heteroatom-doped nanostructured carbon electrocatalysts for rechargeable lithium–air batteries and discusses how different biomass sources affect the cathode's composition, morphology, and structure–activity relationship. It gives a reasonable approach to doping methodologies, which may guide non-noble electrocatalyst and electrode designs. [ABSTRACT FROM AUTHOR]

Ordered intermetallics contribute to a unique class of catalyst materials due to their rich atomic features. Further engineering of ordered intermetallics at a mesoscopic scale is of great importance to expose more active sites and introduce new functions. Recently, multidimensionally ordered mesoporous intermetallic (MOMI) nanoarchitectonics, which subtly integrate atomically ordered intermetallics and mesoscopically ordered mesoporous structures, have held add-in synergies that not only enhance catalytic activity and stability but also optimize catalytic selectivity. In this tutorial review, we have summarized the latest progress in the rational design, targeted synthesis, and catalytic applications of MOMIs, with a special focus on the findings of our group. Three strategies, including concurrent template route, self-template route, and dealloying route, are discussed in detail. Furthermore, physicochemical properties and catalytic performances for several important reactions are also described to highlight the remarkable activity, high stability, and controllable selectivity of MOMI nanoarchitectonics. Finally, we conclude with a summary and explore future perspectives in the field to contribute to wider applications. [ABSTRACT FROM AUTHOR]

An efficient heterogeneous Pd/Cu synergistic catalysis system without a ligand was utilized for C–H arylation of azoles. The reaction exhibits excellent catalytic activity with high functional group tolerance. The synergistic effect between the Cu2O core and PdCu shell was confirmed, whereas pure PdCu nanocages and Cu2O exhibited negligible catalytic activity. [ABSTRACT FROM AUTHOR]

In this article, the synthesis of bis(phosphine), o-Ph2PC6H4C(O)N(H)CH2C6H4PPh2-o (1) (hereafter referred to as "PCNHCP" and its anionic form as "PCNCP") and its group 10 metal chemistry and catalytic studies are described. PCNHCP (1) on reaction with NiCl2(DME) and PdCl2(COD) afforded pincer complexes, [MCl{(PCNCP)κ3-P,N,P}] (M = Ni, 2; Pd, 3). A similar reaction of 1 with PtCl2(COD) yielded a chelate complex, [PtCl2{(PCNHCP)κ2-P,P}] (4), which on further treatment with LiHMDS produced the 1,2-azaphospholene-phosphine complex, [PtCl(Ph){(o-P(Ph)C6H4CONCH2C6H4PPh2-o)κ2-P,P}] (5) via P–C/P–N bond metathesis. Passing dry HCl gas through the solution of 5 resulted in benzene elimination to form [PtCl2{(o-P(Ph)C6H4CONCH2C6H4PPh2-o)κ2-P,P}] (6). Treatment of 1 with PtCl2(COD) and Pt(Cl)(Me)(COD) in the presence of a base resulted in pincer complexes [PtX{(PCNCP)κ3-P,N,P}] (X = Cl, 7; Me, 8). Nickel complex 2 catalyzed the Suzuki–Miyaura cross coupling reaction between bromobenzene and phenyl boronic acid to give the corresponding biphenyls in good yield. The platinum complex 5 showed good catalytic activity towards regio- and stereoselective hydroboration of terminal alkynes. Both the catalytic reactions were performed under mild reaction conditions with a very low catalyst loading. [ABSTRACT FROM AUTHOR]

In α-diimine nickel catalyst-mediated ethylene polymerization, adjusting catalytic parameters such as steric and electronic factors, as well as spectator ligands, offers an intriguing approach for tailoring the thermal and physical properties of the resulting products. This study explores two sets of C2-symmetric α-diimine nickel complexes—nickel bromide and nickel chloride—where ortho-steric and electronic substituents, as well as nickel halide, were varied to regulate simultaneously chain walking, chain transfer, and the properties of the polymers produced. These complexes were activated in situ with Et2AlCl, resulting in exceptionally high catalytic activities (in the level of 106–107 g (PE) mol−1 (Ni) h−1) under all reaction conditions. Nickel bromide complexes, with higher ortho-steric hindrance, exhibited superior catalytic activity compared to their less hindered counterparts, whereas the reverse was observed for complexes containing chloride. Increased steric hindrance in both sets of complexes facilitated higher polymer molecular weights and promoted chain walking reactions at lower reaction temperature (40 °C), while the effect became less pronounced at higher temperature (100 °C). However, the electron-withdrawing effect of ortho-substituents hindered the rate of monomer insertion, chain propagation, and chain walking reactions, leading to the synthesis of semi-crystalline polyethylene with an exceptionally high melt temperature of 134.6 °C and a high crystallinity of up to 31.9%. Most importantly, nickel bromide complexes demonstrated significantly higher activity compared to their chloride counterparts, while the latter yielded polymers with higher molecular weights and increased melt temperatures. These high molecular weights, coupled with controlled branching degrees, resulted in polyethylenes with excellent tensile strength (up to 13.9 MPa) and excellent elastic properties (up to 81%), making them suitable for a broad range of applications. [ABSTRACT FROM AUTHOR]

Superatoms are special clusters with similar physicochemical properties to individual atoms in the periodic table, which open up new avenues for exploring inexpensive catalysts. Given that the ZrO superatom possesses the same number of valence electrons as a Pd atom, the mechanisms of the Suzuki–Miyaura reaction catalyzed by (ZrO)n (n = 1–4) clusters have been investigated and compared with the corresponding Pdn (n = 1–4) species to explore superatom-based catalysts for the formation of C–C bonds via a density functional theory (DFT) study. It was interesting to find that the catalytic activities of (ZrO)n (n = 1–4) towards the Suzuki–Miyaura reaction gradually improved as the cluster size increased. Therefore, to obtain more efficient catalysts, the catalytic activity of a well-designed (ZrO)12 nanocage towards this cross-coupling reaction has been further evaluated. Gratifyingly, this nanocage shows excellent catalytic performance for the considered coupling reaction, which is even comparable to that of the commonly used Pd catalyst and outperforms the corresponding Pd12 cluster. We hope this study can not only provide valuable guidance for the development of noble metal-like catalysts for C–C bond formation, but also expand the application of superatoms in the catalysis of organic reactions. [ABSTRACT FROM AUTHOR]

The oxidation of glycerol to dihydroxyacetone (DHA) represents an efficient and economical process route. Although preparing Au/CuO catalysts from plant constituents has emerged as a novel approach for synthesizing biocompatible products, the complexity of plant constituents means that the active components still need to be clarified, making it challenging to control catalytic activity. In this study, we effectively separated and identified the active components of Syringa oblata Lindl. (SoL) leaf using column chromatography, and synthesized a series of Au/CuO catalysts from the different separated samples. Glycerol catalytic evaluation experiments showed that the S3 fraction, mainly consisting of phenolic substances, exhibited the highest catalytic activity, with a glycerol conversion rate of 86.6% and DHA selectivity of 82.0%, exceeding the activity of most current catalysts. A series of experiments and characterizations demonstrated the differences in reducibility and protective ability among the separated samples, and the preparation and glycerol reaction conditions for optimal performance are systematically optimized. This work provides in-depth insights into the preparation of catalysts using plant-based methods. [ABSTRACT FROM AUTHOR]

Here we report the synthesis of series of bipyridine-based porous polymers as macroligands for molecular copper complexes. The resulting Cu@N-POP solids efficiently catalyze the dehydrogenative N–N coupling of di-p-tolylamine into the corresponding hydrazine using oxygen as the oxidant. The heterogenization of the Cu-based catalyst within porous macroligands improved the catalytic activity with regard to previously reported Cu-based molecular homogeneous systems. Increasing the availability of the bipyridine sites to Cu coordination led to enhanced catalytic performances. [ABSTRACT FROM AUTHOR]

Pyrazolyl-containing aryliodolium salts undergo transformation to iodopyrazoles accompanied by the formation of a new Csp2–Csp2 bond in the presence of a base (DIPEA, NaOH, or K2CO3). The plausible mechanism of the base-mediated reaction is suggested. The catalytic activity of the iodine-containing species is studied in the model reaction. [ABSTRACT FROM AUTHOR]