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Converting CO2 into useful chemicals using metal catalysts is a significant challenge in chemistry. Among the various catalysts reported, transition metal lanthanide hybrid {3d–4f} complexes stand out for their superior efficiency and site selectivity. However, unlike transition metal catalysts, understanding the origin of this efficiency in lanthanides poses a challenge due to their orbital degeneracy, rendering the application of DFT methods ineffective. In this study, we employed a combination of density functional theory (DFT) and ab initio CASSCF/RASSI‐SO calculations to explore the mechanism of CO2 conversion to cyclic carbonate using a 3d–4f heterometallic catalyst for the first time. This work unveils the importance of 3d and 4f metal cooperativity and the role of individual spin‐orbit states in dictating the overall efficiency of the catalyst. [ABSTRACT FROM AUTHOR]

Heterocycles are important compounds existed in diverse advanced chemicals, functional materials, bioactive molecules and natural products. Different strategies through transition metal‐catalyzed alkyne cyclization have been developed to synthesize various heterocycles. The merger of alkyne cyclization and metal nanoparticle catalysis has emerged as an important approach to diverse heterocycles. By using different kinds of metal nanoparticle catalysts, such as gold, silver, copper and palladium nanoparticles, a number of heterocycles are prepared with high yield and selectivity in a green, sustainable and highly efficient manner. This review summarizes and discusses recent achievements in metal nanoparticle‐catalyzed alkyne cyclization for the synthesis of heterocycles. [ABSTRACT FROM AUTHOR]

The direct functionalization of quinones has always fascinated research communities due to their biological and redox activities and subsequent application. Quinone motifs play a vital role as precursors for many bioactive compounds and materials; hence, many ingenious methodologies have been elaborated for exploring these units. A significant part of the synthetic strategies towards the functionalized quinones has been achieved by installing substituents on hydroquinones, phenols, or quinone itself by different oxidative coupling reactions via radical pathways with or without the utilization of metal catalysts. The functionalization of simple quinones via direct C−H bond remains challenging due to their inherited electronic nature and high bond dissociation energy. This review article summarizes the recent advancement made for functionalized quinones through direct functionalization of simple quinones. Our primary focus will be on the synthetic approaches and mechanistic pathways of these reactions that have appeared in the last two decades, along with a short historical importance of the quinone family. [ABSTRACT FROM AUTHOR]

The electrocatalytic urea oxidation reaction (UOR) provides a promising alternative pathway for oxygen evolution in water electrolysis due to its lower thermodynamic barriers. Developing efficient nonprecious metal UOR catalysts is important. Rational design of heterogeneous structures to regulate the morphology and electronic structure is an effective method to improve the activity of electrocatalysts. Herein, a unique heterostructure of ultrathin NiCo-LDH supported by FeNiCoS4 was constructed for the UOR via a facile hydrothermal followed by electrodeposition process. The electrode exhibits superior activity and stability in a solution of 1 M KOH containing 0.33 M urea, with a potential of 1.366 V at 50 mA cm−2 and excellent durability over 48 h. The outstanding performance is attributed to the high conductivity of FeNiCoS4, ultrathin NiCo-LDH and the strong interface interaction between the two components, regulating the local electronic structure of the active metals. This work represents an effective strategy for the preparation of an efficient UOR catalyst with promising applications. [ABSTRACT FROM AUTHOR]

[Display omitted] K-doped Mn–Ce solid solution catalysts were synthesized using a combination of coprecipitation and hydrothermal methods, demonstrating excellent performance in benzene oxidation. The catalyst K 1 Ce 5 Mn 5 exhibited comparable activity to noble metal catalysts, achieving a 90 % benzene conversion at approximately 194 ℃. Durable tests under dry and moist conditions revealed that the catalyst could maintain its activity for 50 h at 218 ℃ and 236 ℃, respectively. Characterization results indicated that the catalyst's enhanced activity resulted from the weakened Mn–O bonding caused by the introduction of K+, facilitating the activation of oxygen and its involvement in the reaction. CeO x , the main crystalline phase of Mn–Ce solid solutions, provided abundant oxygen vacancies for capturing and activating oxygen molecules for the weakened Mn–O structures. This conclusion was further supported by partial density of state analysis from density functional theory computations, revealing that the introduction of K+ weakened the orbital hybridization of Mn3d and O2p. Finally, in situ diffuse reflectance infrared Fourier-transform spectroscopy (in situ DRIFTS) studies on Ce 5 Mn 5 and K 1 Ce 5 Mn 5 catalysts suggested that the introduction of K+ promoted the conversion of adsorbed benzene. Furthermore, intermediate products were transformed more rapidly for K 1 Ce 5 Mn 5 compared to Ce 5 Mn 5. [ABSTRACT FROM AUTHOR]

[Display omitted] Engineering platinum-free catalysts for hydrogen evolution reaction (HER) with high activity and stability is essential for electrochemical hydrogen production. In this paper, we report the synthesis of cobalt-doped AlNi 3 /NiO (Co-AlNi 3 /NiO) electrode with three-dimensional nanoporous structure via chemical dealloying method. Density functional theory (DFT) calculations reveal that Co-AlNi 3 /NiO can accelerate water adsorption / dissociation and optimize adsorption–desorption energies of H* intermediates, thus improving the intrinsic HER activity. Both the introduction of Co and Al can efficiently ameliorate the electronic density around Ni sites of NiO and AlNi 3 , which can effectively reduce the energy barrier towards Volmer–Heyrovsky reaction and thus synergistically promote the hydrogen evolution. Benefiting from the large electrochemical active surface area, high electrical conductivity and electronic effect, the nanoporous Co-AlNi 3 /NiO catalyst exhibits remarkable HER activity with an overpotential of 73 mV at a current density of 10 mA cm−2 in alkaline condition, outperforming most of the reported non-precious metal catalysts. The nanoporous Co-AlNi 3 /NiO catalyst can operate continuously over 1000 h at high current densities with a robust stability. This work provides a new vision for the development of low-cost and efficient electrocatalysts for energy conversion applications. [ABSTRACT FROM AUTHOR]

Produced waters are often treated in open lagoons where hydrogen sulfide (H2S) can off gas, posing a risk to human health and the environment. The aim of this study was to optimize a treatment process using hydrogen peroxide (H2O2) to oxidize H2S while minimizing off gassing. Samples of produced water from West Texas and laboratory-prepared waters utilizing sodium sulfide (Na2S) or biogenic polysulfides were oxidized with H2O2 alone or in combination with copper or iron catalysts, sodium hydroxide (NaOH), or a commercial sulfide oxidizer, HydroPower Green™. Sulfur speciation was measured using Hach test kits for sulfide/sulfate/sulfite and Dräger tubes for headspace H2S. HydroPower Green™ (HPG) helped to reduce H2S in the headspace of water samples; some of this was pH related as NaOH also worked, but not as well as HPG. The dose of peroxide necessary to oxidize sulfides to sulfate is a function of the oxidation-reduction potential (Eh) of the water and total sulfide concentration as well as pH; approximately a 1–4:1 ratio of peroxide to sulfide concentration was needed to oxidize sulfidic waters of pH 7–10 with half-lives under 30 min. Both copper and iron catalysts reduce H2O2 demand and the half-life of H2S. Peracetic acid (PAA) and copper (II) sulfate pentahydrate (CuSO4, 5H2O) were explored as biocides for controlling sulfate-reducing bacteria (SRBs) that produce H2S. An AquaSnap (Hygenia) test kit was employed to monitor relative microbial activity in a wetland porewater containing H2S. Microbial regrowth occurred after a few days using the highest dose of PAA; these results showed that PAA was being used by bacteria as a carbon source even after the initial substantial reduction in the microbial activity. CuSO4, 5H2O at a dose of 1 ppm prevented microbial regrowth. The recommended treatment process from this research is determined by jar testing with H2O2, a base for pH control, a biocide, and possibly a metal catalyst or other co-oxidants in order to achieve oxidation of sulfides without H2S release or the precipitation of metal carbonates or oxides. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) materials, known for their distinctive electronic, mechanical, and thermal properties, have attracted considerable attention. The precise atomic-scale synthesis of 2D materials opens up new frontiers in nanotechnology, presenting novel opportunities for material design and property control but remains challenging due to the high expense of single-crystal solid metal catalysts. Liquid metals, with their fluidity, ductility, dynamic surface, and isotropy, have significantly enhanced the catalytic processes crucial for synthesizing 2D materials, including decomposition, diffusion, and nucleation, thus presenting an unprecedented precise control over material structures and properties. Besides, the emergence of liquid alloy makes the creation of diverse heterostructures possible, offering a new dimension for atomic engineering. Significant achievements have been made in this field encompassing defect-free preparation, large-area self-aligned array, phase engineering, heterostructures, etc. This review systematically summarizes these contributions from the aspects of fundamental synthesis methods, liquid catalyst selection, resulting 2D materials, and atomic engineering. Moreover, the review sheds light on the outlook and challenges in this evolving field, providing a valuable resource for deeply understanding this field. The emergence of liquid metals has undoubtedly revolutionized the traditional nanotechnology for preparing 2D materials on solid metal catalysts, offering flexible possibilities for the advancement of next-generation electronics. [ABSTRACT FROM AUTHOR]

Supported metal catalysts with appropriate metal‐support interactions (MSIs) hold a great promise for heterogeneous catalysis. However, ensuring tight immobilization of metal clusters/nanoparticles on the support while maximizing the exposure of surface active sites remains a huge challenge. Herein, we report an Ir/WO3 catalyst with a new enrooted‐type MSI in which Ir clusters are, unprecedentedly, atomically enrooted into the WO3 lattice. The enrooted Ir atoms decrease the electron density of the constructed interface compared to the adhered (root‐free) type, thereby achieving appropriate adsorption toward oxygen intermediates, ultimately leading to high activity and stability for oxygen evolution in acidic media. Importantly, this work provides a new enrooted‐type supported metal catalyst, which endows suitable MSI and maximizes the exposure of surface active sites in contrast to the conventional adhered, embedded, and encapsulated types. [ABSTRACT FROM AUTHOR]

Developing stable electrocatalysts with accessible isolated sites is desirable but highly challenging due to metal agglomeration and low surface stability of host materials. Here we report a general approach for synthesis of single‐site Fe electrocatalysts by integrating a solvated Fe complex in conductive macroporous organic networks through redox‐active coordination linkages. Electrochemical activation of the electrode exposes high‐density coordinately unsaturated Fe sites for efficient adsorption and conversion of reaction substrates such as NO3− and H2O. Using the electrode with isolated active Fe sites, electrocatalytic NO3− reduction and H2O oxidation can be coupled in a single cell to produce NH3 and O2 at Faradaic efficiencies of 97 % and 100 %, respectively. The electrode exhibits excellent robustness in electrocatalysis for 200 hours with small decrease in catalytic efficiencies. Both the maximized Fe‐site efficiency and the microscopic localization effect of the conductive organic matrix contribute to the high catalytic performances, which provides new understandings in tuning the efficiencies of metal catalysts for high‐performance electrocatalytic cells. [ABSTRACT FROM AUTHOR]

Catalyst deactivation by sintering and coking is a long‐standing issue in metal‐catalyzed harsh high‐temperature hydrocarbon reactions. Ultrathin oxide coatings of metal nanocatalysts have recently appeared attractive to address this issue, while the porosity of the overlayer is difficult to control to preserve the accessibility of embedded metal nanoparticles, thus often leading to a large decrease in activity. Here, we report that a nanometer‐thick alumina coating of MgAl2O4‐supported metal catalysts followed by high‐temperature reduction can transform a nonporous amorphous alumina overlayer into a porous Mg1‐xAl2Oy crystalline spinel structure with a pore size of 2–3 nm and weakened acidity. The high porosity stems from the restrained Mg migration from the MgAl2O4 support to the alumina overlayer through solid‐state reactions at high temperatures. The resulting Ni/MgAl2O4 and Pt/MgAl2O4 catalysts with a porous crystalline Mg1‐xAl2Oy overlayer achieved remarkably high stability while preserving much higher activity than the corresponding alumina‐coated Ni and Pt catalysts on MgO and Al2O3 supports in the reactions of dry reforming of methane and propane dehydrogenation, respectively. [ABSTRACT FROM AUTHOR]

Electrocatalysts for hydrogen production play a crucial role in advancing the green economy. However, the sluggish kinetics of the hydrogen evolution reaction (HER) limited its application. Therefore, efficient strategies with a tailored d-band center adjustment are highly desirable. In this study, we synthesized N, P-doped carbon matrix-confined Mo-doped FeP nanoparticles using a simple strategy to optimize the catalyst's d-band center. Mo-FeP@NPC presents an excellent HER performance of 63 mV (H2SO4) and 116 mV (KOH) at −10 mA cm−2 in acid and alkaline electrolytes, separately. Theoretical calculations confirm that the outstanding HER performance originates from the strong electronic coupling between atoms, thus upshifting the d-band center and increasing H intermediate adsorption on the active sites. Furthermore, the N, P-doped carbon matrix protects the Mo-doped FeP nanoparticles from aggregation, exposing more active sites during hydrogen production. This work provides new avenues for applying highly efficient metal phosphide catalysts for the HER. [ABSTRACT FROM AUTHOR]

To replace depleting freshwater resources, seawater, with its abundance and economy, has become a more favourable option for water electrolysis. However, seawater electrolysis necessitates electrocatalysts with excellent activity as well as resistance to Cl− corrosion. Herein, we utilized a biowaste, eggshell membranes, as a versatile platform to fabricate sulfide electrocatalysts for the oxygen revolution reaction (OER). Structural analyses including X-ray diffraction, X-ray photoelectron spectroscopy and Raman spectroscopy tests indicated that the introduction of iron into the cobalt sulfide lattice greatly modified the structures of the sulfide. Electrochemical tests and operando electrochemical Raman spectroscopy showed that the introduction of Fe adjusted the electronic structure of Co9S8, facilitating the formation of Co4+ species, which serve as the major active sites for OER, thereby effectively improving the catalyst performance. The optimal Co8FeS8/ESM-900 sample can achieve a current density of 10 mA cm−2 in alkaline freshwater, simulated seawater, and natural seawater at overpotentials of 270, 271, and 324 mV, respectively, which are lower than the overpotentials of 273, 272, and 337 mV obtained from IrO2. The sulphate passivation layer formed during the OER process can effectively repel Cl−, leading to outstanding corrosion resistance. The Co8FeS8/ESM-900 catalyst can be continuously operated in seawater electrolysis for 200 000 s. A (−)Pt/C‖‖Co8FeS8/ESM-900(+) electrolyzer required only 1.629, 1.623, and 1.648 V to yield a current density of 10 mA cm−2 for the electrolysis of alkaline freshwater, simulated seawater, and natural seawater, respectively, which are superior to the performance of the (−)Pt/C‖‖IrO2(+) electrolyzer. In virtue of its low cost, high efficiency and outstanding stability, the catalyst reported in this study is promising in practical seawater electrolysis. [ABSTRACT FROM AUTHOR]

The utilization of plant polyphenols as catalyst carriers holds promise for environmentally friendly catalysis. However, challenges such as the inhomogeneous distribution of organic ligands often hinder their effectiveness. In this study, lignin–metal supramolecular framework were formed through ionic coordination self-assembly, achieved by oxidative ammonolysis modified lignin. The specific spatial domain-limiting effect of lignin–metal supramolecular framework ensures the dispersion and stability of catalyst active sites. Carbon-coated trimetallic catalysts (Ru–FeNi@OALC) derived from lignin–metal supramolecules exhibit promising performance, with low overpotentials for the oxygen evolution reaction (OER, η10 = 290 mV) and the hydrogen evolution reaction (HER, η10 = 52 mV), surpassing commercial noble metal catalysts. Additionally, these catalysts demonstrate long-lasting water-splitting performance, highlighting their potential for sustainable catalytic reactions. Molecular simulations and DFT theoretical calculations elucidate the feasibility of lignin oxidative ammonolysis modification and reveal the coordination mechanism. Furthermore, the abundant defects and disorder in the coordination polymer-derived carbon materials optimize electron transfer processes and accelerate reaction kinetics. This construction strategy towards designable polyphenol–metal supramolecular framework presents a promising avenue for the green synthesis of a variety of metal/carbon composite catalysts, contributing to sustainable catalysis and environmental protection. [ABSTRACT FROM AUTHOR]

Single atom-based catalysts (SACs), due to their exceptional electrocatalytic behavior, have been explored for numerous applications such as the oxygen reduction reaction, thermo-catalytic CO2 reduction, and other catalytic activities. Ammonia is one of the most used chemical compounds, and its electrochemical synthesis is a promising alternative as it is simple and cost-effective and shows selective tunability towards the synthesis. Utilizing single-atom electrocatalysts with comparatively low metal mass loading yet exceptional activity could be a better approach to maximize ammonia production. Herein, we report a practically viable magnesium SAC (MgNxC) for the promising reduction of nitrate to ammonia. The catalyst was prepared using green leaf extracts of Spinacia oleracea via simple one-step pyrolysis. We optimized their synthesis temperature to scrutinize the effect of SAC formation and their variation on the catalysis efficacy. The MgNxC650 catalyst, anchored on a defective graphitic matrix, exhibits the best-optimized potential of −0.58 V vs. RHE, a faradaic efficiency of 81.5 ± 2.9% and a yield rate of 392.5 ± 41.2 μmol h−1 mg−1cat. with excellent repeatability. A comprehensive study of the nature of the heterojunction formed at the reactive interface of MgNxC catalysts was carried out by Mott–Schottky analysis to probe the band structure of the intrinsically induced metal–semiconductor junction in the MgNxC catalysts, followed by the analysis of parameters like flat band potential and carrier density correlation. DFT is employed to optimize the most stable reactive site and various reaction pathways for favorable nitrate reduction reaction with probable reaction intermediates were explored. Collectively, our work demonstrates a simple, cost-effective, and convenient way to synthesize SACs. Moreover, it provides clear evidence that chlorophyll moieties can be used as a template to prepare metal catalysts singly anchored on the graphitic carbon matrix. [ABSTRACT FROM AUTHOR]

This review covers recent progress on transition metal dichalcogenides (TMDs) as bifunctional electrocatalysts for Zinc‐air batteries (ZABs), emphasizing their suitable surface area, electrocatalytic active sites, stability in acidic/basic environments, and tunable electronic properties. It discusses strategies like defect engineering, doping, interface, and structural modifications of TMDs nanostructures for enhancing the performances of ZABs. Zinc‐air batteries are promising energy storage devices owing to their high energy density, low cost, and environmental friendliness. However, the development of durable and efficient bifunctional electrocatalysts is a major concern for Zn‐air batteries. In this review, we summarize the recent progress on transition metal dichalcogenides (TMDs) as bifunctional electrocatalysts for Zn‐air batteries. We discuss the advantages of TMDs, such as high activity, good stability, and tunable electronic structure, as well as the challenges, such as low conductivity, poor durability, and limited active sites. We also highlight the strategies for fine‐tuning the properties of TMDs, such as defect engineering, doping, hybridization, and structural engineering, to enhance their catalytic performance and stability. We provide a comprehensive and in‐depth analysis of the applications of TMDs in Zn‐air batteries, demonstrating their potential as low‐cost, abundant, and environmentally friendly alternatives to noble metal catalysts. We also suggest future directions like exploring new TMDs materials and compositions, developing novel synthesis and modification techniques, investigating the interfacial interactions and charge transfer processes, and integrating TMDs with other functional materials. This review aims to illuminate the path forward for the development of efficient and durable Zn‐air batteries, aligning with the broader objectives of sustainable energy solutions. [ABSTRACT FROM AUTHOR]

The reverse water‐gas shift (RWGS) reaction serves as a critical pathway for converting CO2 into diverse chemicals. The Mars–van Krevelen (MvK) mechanism, which leverages lattice oxygen as the oxidant and oxygen vacancies as reductants, offers an alternative catalytic strategy for the selective RWGS reaction. While Mn‐substituted SrTiO3 (i. e., SrTi0.8Mn0.2O3) has been shown to promote the RWGS reaction selectively via the MvK mechanism, achieving a sufficient conversion of CO2 necessitates elevated temperatures. This study investigated the effect of Pd‐loaded SrTi0.8Mn0.2O3 on the activation of adsorbed H2 molecules, which generated oxygen vacancies and enhanced CO2 conversion. Notably, 1.0 wt % Pd‐loaded SrTi0.8Mn0.2O3 yielded 13.4 % of CO at 673 K, whereas pristine SrTi0.8Mn0.2O3 and Pd‐loaded SrTiO3 yielded negligible or minimal amount of CO. Hydrogen temperature‐programmed reduction and X‐ray absorption spectroscopy measurements revealed that Pd promoted the formation of oxygen vacancies via both thermodynamic and kinetic mechanisms. Fourier transform infrared spectroscopy and kinetic studies revealed that the RWGS reaction over Pd‐loaded SrTi0.8Mn0.2O3 proceeded primarily via the MvK mechanism with a partial contribution from the Langmuir–Hinshelwood mechanism. This study underscores the effectiveness of combining metal and MvK‐type catalysts to enhance the efficiency of the RWGS reaction. [ABSTRACT FROM AUTHOR]

Cobalt single atom catalysts (SACs) have exhibited promising performance in both the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), positioning them as potential dual‐functional catalysts for Zn‐air battery. However, the long‐standing challenge lies in achieving satisfactory dual‐functionality and stability of these SACs. In this study, to optimize the 4e‒ ORR performance, boron (B) atoms are employed with low electronegativity to regulate the structure of the Co–N–C catalytic center. This resulted in the formation of an asymmetrically coordinated Co metal center catalyst (Co‐N3B). Compared to the Co‐N4, Co‐N3B exhibited lower free energy for ORR and stronger adsorption energy toward *O species, effectively suppressing the 2e‒ ORR pathway at the cobalt site and preventing catalyst corrosion induced by hydrogen peroxide (H2O2) in ORR reactions, thereby enhancing catalyst stability. In situ attenuated total reflectance surface‐enhanced infrared absorption spectroscopy (ATR‐SEIRAS) further validated excellent interaction between Co active centers and O intermediates. Furthermore, the self‐made rechargeable zinc‐air battery demonstrated remarkable discharge peak power density (≈253 mW cm‒2), energy density (≈819 mAh g‒1), and cyclic stability exceeding 110 h. This study provides new insights into constructing catalysts with atomic‐level precision and offers strong references for practical applications in energy storage and convension electrocatalysts. [ABSTRACT FROM AUTHOR]

Introducing the second metal is an effective strategy to ameliorate oxygen reduction reaction (ORR) performance of cobalt and nitrogen doped carbon materials (Co-NC). In this study, Sn modulated Co-NC catalysts with enriched active sites (CoSn-NC) were synthesized by using formamide as ligand. Co and Sn bimetals coexist on nitrogen-doped carbon carriers and coordinated with nitrogen to form M − N active centers. Compared with Co-NC, CoSn -NC exhibited outstanding catalytic activity in terms of early initial potential of 1.04 V and positive half-wave potential of 0.89 V. Electrochemical testing and XPS characterization proved that the addition of Sn enriched the active site of Co-NC. More importantly, the electronic structure of Co–N is adjusted to perfect adsorption energy of the intermediate. The study puts forward a new idea and direction for optimizing single metal Co-NC catalyst. Synopsis: This paper is committed to developing Cobalt-based bimetallic materials with enrich active sites to replace scarce Pt/C for ORR. [Display omitted] • Co and Sn bimetals coexist on nitrogen-doped carbon carriers. • Sn Modulated Co-NC catalysts with enriched active sites. • The M − N structure is the main catalytic site by SCN− toxicity experiments. • CoSn-NC shows enhanced ORR catalytic activity, stability and methanol resistance. [ABSTRACT FROM AUTHOR]

Dry reforming of methane (DRM) takes advantage of greenhouse gases (CH 4 and CO 2) and mitigates their eco-environmental consequences. However, the biggest obstacle for DRM reactions has been the design of catalysts with high resistance to sintering and carbon deposition. In this paper, the embedded bimetallic nickel-cobalt@ silicalite-1 (S1) catalysts (NiCo@S1), with high resistance to sintering and lower carbon deposition, were prepared by grinding crystallization method. The physicochemical characterizations demonstrated that the embedded catalyst for NiCo@S1 could effectively control the size and dispersion of the active metal Ni–Co in the catalyst compared to the supported catalysts for 10Ni/SiO 2 and 10Ni/S1, which further enhance the interaction between the active metal phase and the carrier S1, and greatly minimize the amount of carbon accumulation on the catalysts. After being subjected to a reaction at 700 °C for 6 h, the 10Ni2.5Co@S1 exhibited a significant performance improvement. The instantaneous conversion rate of CH 4 increased from 63.17% to 86.39% (an increase of 23.22%), and the instantaneous conversion rate of CO 2 rose from 70.20% to 88.62% (an increase of 18.42%). Additionally, carbon deposition reduced from 14.58% to 0.82% (a decrease of 13.76%). Therefore, the conceptual design provided a new perspective for designing Ni-based dry reforming catalysts. • An industry-friendly grinding crystallization method has been introduced. • The grinding crystallization method can effectively promote the dispersion of active components、enhance metal-support interaction and prevent the migration of metal nanoparticles and their agglomeration, avoiding sintering, and thus reducing carbon deposition. • 10Ni2.5Co@S1 catalyst showed excellent performance in dry reforming of methane reactions. [ABSTRACT FROM AUTHOR]

The development of high-efficient non-precious metal catalysts for hydrogen evolution reaction (HER) and urea oxidation reaction (UOR) is beneficial to enhance hydrogen evolution efficiency and reduce the cost of electrolyzers. In this paper, nitrogen doped carbon coated NiMoO x rod array (NiMoO x @NC) is successfully synthesized on nickel foam (NF). The nitrogen-doped carbon layer protects the unique rod array structure of the catalyst, making it exhibit both superhydrophilicity and superaerophobicity underwater. This facilitates the full diffusion of the electrolyte on the catalyst surface and the rapid departure of the hydrogen bubbles from the catalyst surface. Consequently, NiMoO x @NC demonstrates an electrocatalytic performance of 1.380 V (vs RHE) at 25 mA cm−2 for UOR and an overpotential of 126 mV at 25 mA cm−2 for HER. Employing NiMoO x @NC as both the anode and cathode in the urea-assisted hydrogen evolution, the system outputs 50 mA cm−2 at 1.680 V. This breakthrough provides an efficient and cost-effective approach for fabricating nickel molybdenum-based metal oxides. [Display omitted] • A unique core-shell structure is successfully constructed. • The nanorod array can be maintained with the protection of carbon layer. • The catalyst exhibits superhydrophilicity and superaerophobicity. • The as-prepared catalyst displays outstanding performance for HER and UOR. [ABSTRACT FROM AUTHOR]

CoCu catalyst had been considered as efficient candidate in higher alcohol synthesis from syngas (HAS), but the higher fraction of methanol restrained the yields of higher alcohols and had the adverse effect on product separation. Herein, the novel designing concept of CoCu catalyst with limited methanol formation was proposed by studying the deviated Anderson-Schulz-Flory (ASF) distribution of the obtained alcohol. Two types of KIT-6 supported CoCu catalyst with diffident metal proximity were successfully prepared and applied in HAS. The characterization results and catalytic performance demonstrated that "concave" type alcohol distribution was caused by separation of bimetallic phase. The transformation from "linear" type to "concave" type over traditional CoCu catalyst during the reaction illustrated that higher fraction of methanol was ascribed to the coexistence of active sites for methanol synthesis over catalysts. Moreover, the study on "convex" type indicated that promoter-assisted CoCu catalyst favored to limit the formation of methanol. [Display omitted] • Proposing a designing concept of CoCu catalyst with limited methanol formation. • The separated Co and Cu species resulted in "concave" type of alcohol distribution. • Methanol formation was ascribed to isolated Cu species and unsaturated Co species. • Promoter assisted CoCu catalysts favored for limiting methanol formation. [ABSTRACT FROM AUTHOR]

Achieving active site engineering at the atomic level poses a significant challenge in the design and optimization of catalysts for energy‐efficient catalytic processes, especially for a reaction with two reactants competitively absorbed on catalytic active sites. Herein, we show an example that tailoring the local environment of cobalt sites in a robust metal–organic framework through substituting the bridging atom from −Cl to −OH group leads to a highly active catalyst for oxygen activation in an oxidation reaction. Comprehensive characterizations reveal that this variation imparts drastic changes on the electronic structure of metal centers, the competitive reactant adsorption behavior, and the intermediate formation. As a result, exceptional low‐temperature CO oxidation performance was achieved with T25(Temperature for 25 % conversion)=35 °C and T100 (Temperature for 100 % conversion)=150 °C, which stands out from existing MOF‐based catalysts and even rivals many noble metal catalysts. This work provides a guidance for the rational design of catalysts for efficient oxygen activation for an oxidation reaction. [ABSTRACT FROM AUTHOR]

The results of study of catalytic vacuum gas oil oxycracking process in presence of metal zeolite catalysts are presented. Screening of oxides of 10 modifying transition metals (Cu, Ti, V, Cr, Fe, Co, Ni, Cd, Mo, and W) made it possible to disclose the basic differences in the behavior of the catalytic systems. Based on the data obtained, an activity series were constructed (based on the total yield of light fractions): Mo > Ti > Cr > Ni > Fe >W > V > Cd > Co > Cu. Best results for the target fractions were obtained in the presence of molybdenum, titanium, and vanadium zeolite systems (for 195/200-300°C fractions) and for tungsten-containing system (for hydrocarbon gas). Comparison of vacuum gas oil conversion data obtained under catalytic oxycracking conditions with bond strength of the surface oxygen of the metal oxides made it possible to establish their correspondence and to recommend this criterion for choosing catalysts for the process. [ABSTRACT FROM AUTHOR]

5-Alkylated barbituric acids are an important class of compounds that constitute the basic moiety of several clinically used hypnotic drugs. Here we report a catalyst-free domino Knoevenagel-Michael addition involving barbituric acid, aldehyde, and N,N-disubstituted aniline in solvent acetonitrile to synthesize 5-alkylated barbituric acid derivatives (72–94% yield) without using any chromatographic separation techniques. The C-4 position of aniline acts as the Michael donor. All the reactions are successfully performed without catalysts, providing an environment-friendly and economical route for the synthesis. Moreover, catalyst-free reactions are less sensitive to air and moisture unlike many metal catalysts, with easy separation of products, and simple operating procedures as there is no need for catalyst weighing, recovery, and removal. A plausible mechanism is also proposed based on control experiments. [ABSTRACT FROM AUTHOR]

The use of halogen bonding interactions as an alternative to acid and metal catalysts for substrate activation has gained popularity in recent years. In this work we demonstrate a halogen bond assisted activation of chalcones under visible light irradiation for the Friedel‐Crafts reaction with indole to yield β‐indolylketones. The simple and scalable protocol uses the readily available CBr4 as halogen bond catalyst. The targets are produced in 31–94% of yield with excellent functional group tolerance. The proposed mechanism of the reaction is supported by UV‐vis, fluorescence, and NMR spectroscopic studies. Further it is demonstrated that the β‐indolylketones can be oxidised to indole substituted α, β‐unsaturated ketones by DDQ or cyclized to thieno[2,3‐b]indoles in the presence of elemental sulfur and base. [ABSTRACT FROM AUTHOR]

This investigation confirms that the existence of the hydrogen spillover effect (HSPE) in the case of metal catalysts supported on non-reducible monoxides or zeolites is based on a strong corpus of experimental studies, enlarging and deepening previous statements. The structure of hydrogen spillover consists of H/OH pairs conjugated with Mm+/Op− pairs (p = 1 or 2). It is formed by dehydroxylation followed by OH/OH exchange or by the hydrogenation of conjugated pairs. Such a structure imposes the following chemical processes: (i) hydrogenations take place over OH Brönsted acid sites (BAS); (ii) they are excluded over Mm+/Op− Lewis acid sites (LASs), which are deactivating or dehydrogenating; (iii) surface diffusion of hydrogen spillover proceeds through the migration of H/H pairs from LASs to LASs; (iv) the diffusion rates are determined by the oxide supports' basicity; and (v) H/D exchange is proof of the existence of hydrogen spillover. The nature of hydrogen spillover (radical/ionic) depends on the polarity of the H/OH pairs, which in turn, is determined by the basicity of the support. Our concept of conjugated active sites is a good descriptor of the reaction paths at the molecular level. The view of LASs bringing about additional activity to BAS is not pertinent. [ABSTRACT FROM AUTHOR]

Highlights: Metal dusting affords a way to generate metal catalysts in situ from cheap metal sources and a high density of catalyst particles is created, anchored to a metal support. The metal dusting-catalyzed carbon magnifies the second-stage TCD rate and yield by virtue of its greater active surface area. Complementary microscopic, spectroscopic, and thermo-gravimetric characterizations highlight the structural differences between the first (TCD)-stage metal-catalyzed carbon and the second (TCD)-stage carbon-catalyzed carbon. Using model carbons, the TCD carbon's nanostructure did not appear to depend on the nanostructure of the nascent carbon catalyst. In this study, metal dusting is utilized to initiate a two-stage thermo-catalytic decomposition (TCD) process. Stage 1 starts with metal-catalyzed TCD, and in stage 2 the metal-catalyzed carbon catalyzes additional TCD. TEM is presented of the early- versus late-stage TCD to qualitatively illustrate the second-stage TCD by the metal-catalyzed carbons. Corresponding SEM illustrates differences in growth type and surface density between early versus late reaction times, with backscattered imaging differentiating the first- versus second-stage TCD. TGA supports the microscopic inference of a second carbon phase by the presence of an early (low-temperature) reaction peak, characteristic of low-structure or disordered carbon as the second-stage TCD carbon. Raman analysis confirms that the second-stage carbon deposit is more disordered and unstructured, especially at 1000 °C, supported by the ID/IG and La value changes from 0.068 to 0.936 and 65 nm to 4.7 nm, respectively. To further confirm second-stage TCD occurrence upon pre-catalyzed carbons, two carbon blacks are tested. Exposing a combination of edge and basal or exclusively basal sites for the graphitized form, they afford a direct comparison of TCD carbon nanostructure dependence upon the initial carbon catalyst nanostructure. Pre-oxidation of the stainless-steel wool (SSW) prior to TCD is advantageous, accelerating TCD rates and increasing carbon yield relative to the nascent SSW for an equivalent reaction duration. [ABSTRACT FROM AUTHOR]

Hydrogen peroxide (H2O2) is an important chemical with a diverse range of industrial applications in chemical synthesis and medical disinfection. The traditional anthraquinone oxidation process, with high energy consumption and complexity, is being replaced by cost-effective and environmentally friendly alternatives. In order to explore suitable catalysts for the electrocatalytic synthesis of H2O2, the stability of B,N-doped graphene loaded with various p-block metal (PM) single atoms (i.e., PM-NxBy: x and y represent the number of atoms of N and B, respectively) and the effects of different numbers and positions of B dopants in the second coordination shell on the catalytic performance were studied by density functional theory (DFT) calculations. The results show that Ga-N4B6 and Sb-N4B6 exhibit enhanced stability and 2e− oxygen reduction reaction (ORR) activity and selectivity. Their thermodynamic overpotential η values are 0.01 V, 0.03 V for Ga-N4B6's two configurations and 0.02 V, 0 V for Sb-N4B6's two configurations. Electronic structure calculations indicate that the PM single atom adsorbs OOH* intermediates and transfers electrons into them, resulting in the activation of the O-O bond, which facilitates the subsequent hydrogenation reaction. In summary, Sb-N4B6 and Ga-N4B6 exhibit extraordinary 2e− ORR performance, and their predicted activities are comparable to those of known outstanding catalysts (such as PtHg4 alloy). We propose effective strategies on how to enhance the 2e− ORR activities of carbon materials, elucidate the origin of the activity of potential catalysts, and provide insights for the design and development of electrocatalysts that can be used for H2O2 production. [ABSTRACT FROM AUTHOR]

The low-temperature oxidation of methane gas in coal mine exhaust gas is important for reducing the greenhouse effect and protecting the environment. Unfortunately, the carbon–hydrogen bonds in methane molecules are highly stable, requiring higher reaction temperatures to achieve effective catalytic oxidation. However, metal oxide-based catalysts face the problem of easy sintering and the deactivation of active components at high temperatures, which is an important challenge that catalysts need to overcome in practical applications. In this work, a series of Mn-Co3O4 active components were grown in situ on ZSM-5 zeolite with mesoporous pore structures treated with an alkaline solution via a hydrothermal synthesis method. Due to the presence of polyethylene glycol as a structure-directing agent, manganese can be uniformly doped into the Co3O4 lattice. The large specific surface area of ZSM-5 zeolite allows the active component Mn-Co3O4 to be uniformly dispersed, effectively preventing the sintering and growth of active component particles during the catalytic reaction process. It is worth mentioning that the Mn-Co3O4/meso-ZSM-5-6.67 catalyst has a methane conversion rate of up to 90% at a space velocity of 36,000 mL·g−1·h−1 and a reaction temperature of 363 °C. This is mainly due to the mesoporous ZSM-5 carrier with a high specific surface area, which is conducive to the adsorption and mass transfer of reaction molecules. The active component has an abundance of oxygen vacancies, which is conducive to the activation of reaction molecules and enhances its catalytic activity, which is even higher than that of noble metal-based catalysts. The new ideas for the preparation of metal oxide-based low-temperature methane oxidation catalysts proposed in this work are expected to provide new solutions for low-temperature methane oxidation reactions and promote technological progress in related fields. [ABSTRACT FROM AUTHOR]

The mechanisms of medium- and low-temperature denitrations using selective catalytic reduction (SCR) by combined CO + NH3 on Mn–Ce/activated carbon (AC) catalysts and their poisoning by SO2 were investigated. Several Mn–Ce/AC catalysts prepared and then poisoned by SO2 were used in the study. The physicochemical properties of the catalysts were systematically characterized before and after poisoning, and the mechanism of SO2 poisoning was proposed. SO2 poisoning considerably affects the Mn–Ce/AC catalyst, decreasing its denitration rate from 98% to 47.9% and N2 selectivity from 96 to 85%. This can be attributed to several phenomena. SO2 poisoning increases the surface roughness of the catalyst and results in the formation of Mn(SO4)2, other sulfates, and other substances, which block the catalyst pores and reduce the content of the C and O elements on the catalyst surface as well as its specific surface area, consequently decreasing the adsorption area available for the reaction gas. Moreover, the crystallinity of MnOx on the surface of the catalyst increases, decreasing the contents of Mn4+, Ce4+ and chemosorbed oxygen. In addition, the surface functional groups, such as –COOH, –OH, and C=O, are destroyed, reducing the adsorption sites of the reaction gas and the adsorption capacity of the catalyst, consequently inhibiting the SCR reaction. Ce can reduce the effects of SO2 poisoning on the catalyst because Ce4+ can improve its oxygen storage capacity, increase the adsorption sites for the reaction gas, and react with SO2, preventing sulfate formation and pore blockage. However, excessive Ce loading causes metal agglomeration on the catalyst surface, reducing its denitration efficiency. After SO2 poisoning, the contents of Mn4+, Mn3+, and Ce4+ decreased in the Mn -Ce/AC catalysts, inhibiting the synergistic reaction between Mn and Ce, which decreased the number of oxygen vacancies and Oβ, consequently inhibit the reaction's conversion to fast selective catalytic reduction. Thus, SO2 destroyed the functional groups; occupied the oxygen vacancies and active site; and destroyed the –COOH, O–H, and C=O functional groups on the surface of the Mn–Ce/AC catalyst, reducing the acidity and number of active sites on the catalyst surface. [ABSTRACT FROM AUTHOR]

CO oxidation at mild condition is significant for industrial process but still challenging nowadays, especially for the non-noble metal catalysts. The preparation method significant affect the catalytic activity of the catalyst. Comparing with cobalt supported on tantalum oxide prepared by impregnation method, Co/Ta2O5 prepared by deposition–precipitation method with urea in this study has smaller particle size, higher specific surface area and better redox properties, and these features make the catalyst exhibit higher catalytic activity for CO oxidation at mild condition. 90% CO conversion was achieved at 130 ℃, and CO was fully converted at 150 ℃. The XPS and DRIFTs results show that Co/Ta2O5 has more oxygen vacancies, and the absorbed CO will react with oxygen. The study may provide a new thought for the preparation of catalysts with high activity at mild condition. [ABSTRACT FROM AUTHOR]

In this work, Ni and NiFe LDH are coupled on a carbon cloth to synthesize flexible electrocatalysts with superhydrophilic interfaces. DFT calculations demonstrate that the formation of a unique heterostructure induce the redistribution of the surrounding electrons and increase the total density of states near the Fermi energy level, which optimized the Gibbs free energy for hydrogen adsorption. Under alkaline conditions, the HER overpotential is only 36 mv at a current density of 10 mA cm−2, which is fully comparable to noble metal catalysts. [Display omitted] The rational design of morphology and heterogeneous interfaces for non-precious metal electrocatalysts is crucial in electrochemical water decomposition. In this paper, a bifunctional electrocatalyst (Ni/NiFe LDH), which coupling nickel with nickel–iron layer double hydroxide (NiFe LDH), is synthesized on carbon cloth. At current density of 10 mA cm−2, the Ni/NiFe LDH exhibits a low hydrogen evolution reaction (HER) overpotential of only 36 mV due to the accelerated electrolyte penetration, which is caused by superhydrophilic interface. Moreover, an alkaline electrolyzer is formed and provide a current density of 10 mA cm−2 with a voltage of only 1.49 V. It is confirmed by the density functional theory (DFT) that electron from the Ni layer is transferred to NiFe LDH layer, redistributing the local electron density around the heterogeneous phase interface. Thus, the Gibbs free energy for hydrogen adsorption is optimized. This work provides a promising strategy for the rational regulation of electrons at heterogeneous interfaces and the synthesis of flexible electrocatalysts. [ABSTRACT FROM AUTHOR]

Three multiphase metallaphotoredox catalysts M−Salen−CMP (M Zn, Cu and Co) with dual-catalytic functions were constructed by linking M−salen (M Zn, Cu and Co) and 2, 4, 6-tris(4-ethylphenyl)-1, 3, 5-triazine (TEPT) monomer via covalent bonds. The catalysts M−SATE−CMP (M Zn, Cu and Co) have different d-band centers based on different metal active centers, resulting in the difference of the optical property as well as their adsorption and activation capacities for the reactants. Therefore, they can selectively photocatalytically oxidize β-keto esters to α-hydroperoxide β-keto esters (ROOH) or α-hydroxyl β-keto esters (ROH), where ROOH is an intermediate of ROH. [Display omitted] Photocatalytic selective oxidation plays an important role in developing green chemistry. However, it is challenging to design an efficient photocatalyst for controlling the selectivity of photocatalytic oxidation reaction and exploring its detailed mechanism. Here, we synthesized three conjugated microporous polymers (CMPs) with D-A structures, named M−SATE−CMPs (M Zn, Cu and Co), with different d-band centers based on different metal centers, resulting in the discrepancy in adsorption and activation capacities for the reactants, which produces the selectivity of β-keto esters being catalyzed into α-hydroperoxide β-keto esters (ROOH) or to α-hydroxyl β-keto esters (ROH). Density functional theory (DFT) calculations also demonstrate that the adsorption and activation capacities of the metal active centers in M−SATE−CMPs (M Zn, Cu and Co) for ROOH are the key factors to influence the photocatalytic selective oxidation of β-keto ester. This study provides a promising strategy for designing a metallaphotoredox catalyst whose photocatalytic selectivity depends on the d-band center of metal site in the catalyst. [ABSTRACT FROM AUTHOR]

BACKGROUND RESULTS CONCLUSION The transesterification of butteroil has been shown to alter its lipid chemistry and thus alter the crystallization of the fat. The reaction kinetics and resulting crystallization of the butteroil differ depending on the nature of the catalyst used. Modeling the reaction with vegetable oils is a simpler method for the analysis of resulting products to understand the chemical and physiochemical changes that occur based on catalyst selection. The objective of this work is to perform a chemical transesterification of coconut and corn oil using monovalent and divalent catalysts to investigate the chemical and crystal changes that occur.Coconut and corn oil were subjected to chemical transesterification using both Ca(OH)2 and KOH as catalysts. In both the coconut and corn oil samples, transesterification caused monoglycerides (MAGs) and diacylglycerides (DAGs) to form from the most abundant fatty acid found in each sample. Coconut oil's melting temperature, solid fat content (SFC), and storage modulus decreased as a result of the transesterification, and crystals began to form in the corn oil causing melting thermograms to be evident, higher SFC, and a more viscous oil as a result. Using Ca(OH)2 as a catalyst resulted in more MAG formation, and a higher SFC and melting temperature than when KOH was used as a catalyst.The results demonstrate that the chemical changes that result from transesterification of plant‐based oils change the crystallization behavior of the oils and can therefore be used for different applications in the food industry. © 2024 The Author(s). Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Exploring an efficient nonnoble metal catalyst for hydrogen evolution reaction (HER) is critical for industrial alkaline water electrolysis. However, it remains a great challenge due to the additional energy required for H─OH bond cleavage and the lack of enough H2O adsorption sites for most catalysts. Herein, the integration of oxophilic Eu2O3 with NiCo alloy with evoked multisite synergism to facilitate water dissociation for alkaline HER is proposed. The optimized Eu2O3‐NiCo exhibits excellent HER activity with a low overpotential of only 60 mV at 10 mA cm−2 and good electrochemical stability, which is superior to that of Eu2O3‐free NiCo and comparable to benchmark Pt/C. The key roles of Eu2O3 on the enhanced HER performance of Eu2O3‐NiCo are identified by in situ Raman spectroscopy and theoretical calculations. It is discovered that the Eu2O3 with strong oxophilicity facilitates the adsorption of H2O and the breakage of H─OH bonding while evoking the electron redistribution at Eu2O3/NiCo interface and accelerating the Volmer step in alkaline HER. Furthermore, the obtained Eu2O3‐NiCo as both anode and cathode displays excellent overall water‐splitting activity and stability in 1.0 M KOH solution. It is believed that this study provides an important inspiration to design high‐performance electrocatalysts toward HER based on rare‐earth materials. [ABSTRACT FROM AUTHOR]

Polyester-ether glycol was synthesized with poly(polyol adipate) as starting agent, epoxy alkane as the polymerization monomer, and alkali metal as catalyst. The effects of catalyst dosage on the polymerization was discussed, and its structure was characterized by FTIR and GPC. The self-made polyester-ether glycol was used to prepare polyurethane high-resilience foam and polyurethane elastomer, and the effects of polyester-ether glycol on their mechanical properties were studied. The results showed that the optimum catalyst concentration was 0.6%. When polyester-ether glycol was applied to polyurethane high resilience foam with the addition amount of 15%, it had a significant effect on improving the mechanical properties of the products. Compared with traditional propylene glycol polyether, polyurethane synthesized with polyester-ether glycol had significant advantages in mechanical properties. [ABSTRACT FROM AUTHOR]

The reduction degree of TiO2 support is critical to the performances of metal catalysts. In many previous theoretical calculations, only the bridge oxygen vacancy (Ov) was considered as the electron-donating defect on reduced rutile TiO2 (r-TiO2−x) supports. However, titanium adatoms (Tiad.), oxidized titanium islands (Tiad.On), and acid hydroxyls (ObrH) also exist at the metal/support interface. By conducting density functional theory (DFT) calculations and ab initio molecular dynamics (AIMD) simulations, we compared r-TiO2−x surfaces with Ov, Tiad., Tiad.On, and ObrH sites loaded with Au nanoparticles (NPs). The results showed the Au NPs were oxygen-phobic but titanium-philic, resulting in wetting of Ov and Tiad. but short contact with Tiad.On and ObrH. The Bader charges of Au NPs (QM) showed a good linear relationship with the ideal number of donating electrons (Ne) from the defective sites (QM = −KeNe + QM,S), demonstrating the intrinsic electron allocation at the interface. The Ov, Tiad., and Tiad.On exhibited similar slopes (Ke), relatively steeper than that of ObrH. That means in the scope of Au NP charge state, the Tiad. and Tiad.On have a close electron-donating ability with Ov, but the ObrH donates relatively fewer electrons. This linear relationship can be extended approximately to other metals. The higher the metal work function, the steeper the Ke for easier electron donation from defective sites. The stronger the metal oxygen affinity, the more positive the intercept (QM,S). That explains the easy generation of metallic or negative Pt and Au NPs on r-TiO2−x, but hard for Cu and Zn in experiment. That provides theoretical guidance for regulating the charge of metal NPs over TiO2−x supports. [ABSTRACT FROM AUTHOR]

Electrochemical CO2 reduction (ECO2RR) is capable of converting CO2 into a wide range of value‐added products under relatively mild conditions. Electrocatalyst with high selectivity and activity is crucial for high efficient ECO2RR. Herein, Bi‐In2O3 nanoflower catalysts with different metal ratios synthesized by wet chemical method are used for ECO2RR to produce formate. The results indicate that the hydrogen evolution activity of the Bi‐In2O3 catalysts during ECO2RR is suppressed at a low level and the activity and selectivity of formate production is related to the ratio of Bi to In content in the catalysts. The optimized Bi‐In2O3 catalyst with the ratio of Bi6In94 can achieve a high formate Faradaic efficiency (FEformate) over 80 % under a wide potential range from −0.7 V to −1.2 V vs. RHE, with the maximum value of 88.1 % at −0.7 V vs. RHE. Meanwhile, the highest formate partial current density reaches 47.7 mA cm−2 at −1.2 V vs. RHE and the current density and Faradaic efficiency remain stable during the 10 h stability test. The enhanced formate formation on Bi‐In2O3 NF can be attributed to the synergistic effect between Bi and In according to the characterizations of the Bi‐In2O3 NF. [ABSTRACT FROM AUTHOR]

Denitrogenative organic transformations and related reactions are a class of significant approaches for carrying out unusual C−C/C‐heteroatom (C−O, C−N, C−S) bond‐forming reactions that are usually promoted by Ru, Ir, Pd, Ni, and Cu metal catalysts. In this trait, numerous methods were adopted to synthesize several pharmaceutically valuable N‐ and O‐containing heteroaromatics using 1,2,3‐benzotriazin‐4(3H)‐one as an electrophilic coupling partner. This review involves the recent achievements related to the metal/organo‐catalyzed thermal and visible‐light mediated denitrogenative approaches with 1,2,3‐benzotriazin‐4(3H)‐ones towards the synthesis of imperative N‐heteroaromatic compounds. In addition, metal and oxidant‐free ortho‐functionalization of benzotriazinones by using suitable nucleophilic partners have been discussed. In particular, the most novel methods employing Ni and Pd metal catalysts that have emerged are exhibited. Specific attention has been paid to offering the detailed mechanistic pathway to explain the role of metal catalysts and the mechanism in the absence of metal catalysts in the denitrogenative reactions under a thermal/visible light medium. [ABSTRACT FROM AUTHOR]

We systematically explored NO activation at metal/oxide interfaces by the combination of Sr3Ti2O7, Sr3Fe2O7, CeO2, anatase-TiO2, ZrO2, and γ-Al2O3 supports and the platinum-group metal cluster (Pd4, Pt4, and Rh4) using slab-model density functional theory calculations. These metal clusters can be strongly adsorbed at these metal oxide surfaces. The Pt4 and Rh4 clusters show larger adsorption energies than the Pd4 cluster, yet the γ-Al2O3(100) surface shows smaller adsorption energies than other metal oxide surfaces. One oxygen vacancy close to the metal cluster was constructed to evaluate the NO activation at those metal/oxide interfaces. The O atom of NO refills the oxygen vacancy after NO dissociation, while the N adatom is left on the metal cluster. The exothermic process was identified for the NO activation except for the Sr3Fe2O7 case, indicating the significant role of the interplay between the metal cluster and oxygen vacancy. [ABSTRACT FROM AUTHOR]

[Display omitted] • CuSe-Co 3 Se 4 @VSe 2 nanotube clusters were synthesized by a facile template method. • CuSe-Co 3 Se 4 @VSe 2 was used as a bifunctional catalyst for HER and DSSCs. • CuSe-Co 3 Se 4 @VSe 2 had lower overpotential for basic HER (76 mV@10 mA cm−2). • The PCE (9.64%) of CuSe-Co 3 Se 4 @VSe 2 was much higher than that of Pt (8.39%). Among the various non-precious metal catalysts that drive hydrogen evolution reactions (HERs) and dye-sensitized solar cells (DSSCs), transition metal selenides (TMSs) stand out due to their unique electronic properties and tunable morphology. Herein, the multicomponent selenide CuSe-Co 3 Se 4 @VSe 2 was successfully synthesized by doping with metal element vanadium and selenization on the copper-cobalt carbonate hydroxide (CuCo-CH) template. CuSe-Co 3 Se 4 @VSe 2 exhibited the dandelion-like cluster structure composed of hollow nanotubes doped with VSe 2 nanoparticles. Due to the unique structure and the synergistic effect of various elements, CuSe-Co 3 Se 4 @VSe 2 showed excellent alkaline HER and DSSC performances. The DSSC based on CuSe-Co 3 Se 4 @VSe 2 exhibited an impressive power conversion efficiency (PCE) of 9.64 %, which was much higher than that of Pt (8.39 %). Besides, it possessed a low HER overpotential of 76 mV@10 mA cm−2 and a small Tafel slope of 88.9 mV dec−1 in 1.0 M KOH. [ABSTRACT FROM AUTHOR]

[Display omitted] The electrocatalytic oxygen reduction reaction (ORR) is crucial for energy conversion systems such as fuel cells and metal-air batteries. Boron carbon nitrogen (BCN) is a novel functional material with a high specific surface area, excellent corrosion resistance, and outstanding electrochemical stability. These properties make BCN an effective ORR catalyst and a promising support for metal catalysts. This study leveraged the strong interaction between BCN and metals to anchor platinum nanoparticles (Pt NPs) onto the BCN surface (Pt/BCN), significantly enhancing the durability of traditional Pt/C catalysts in ORR. The half-wave potential of Pt/BCN is 0.927 V, higher than Pt/XC-72R (0.857 V) and commercial Pt/C (0.879 V). Notably, after 10,000 durability test cycles, the mass activity (MA) of Pt/XC-72R and commercial Pt/C decreased by 67 % and 75 %, respectively. Even after 50,000 cycles, Pt/BCN exhibited only a 54 % decrease in MA. Experimental data and density functional theory calculations confirmed increased electron transfer from Pt to the BCN support, indicating a strong electronic metal-support interaction (EMSI) between Pt and BCN. This strong EMSI effectively anchored the Pt NPs, preventing migration and aggregation during the ORR process. Consequently, our research introduces a novel electrocatalyst support material with significant potential for ORR and broader applications. [ABSTRACT FROM AUTHOR]

We reported nucleation mechanisms of InP directly on Si (8% lattice mismatch) under confined structures, called micro-crucibles, at ultra-high vacuum (UHV) by chemical beam epitaxy. These micro-crucibles are used to induce lateral growth in the presence of a micro-scale Au catalyst. It is found that at this UHV condition, the kinetics is dictated predominantly by adatom surface diffusion. Using a two-step growth process ((1) In-only exposure, then, (2) simultaneous In and P exposures), InP islands have been successfully nucleated on Si substrates under micro-crucible structures. The nucleation of these InP islands strongly depends on the metal catalyst location relative to the micro-crucible opening with metal catalysts residing closer to the opening having a higher chance to get incorporated with In and P atoms. Importantly, we found that using smaller micro-crucibles with double openings can increase the possibility of having metal catalysts reside near either opening and nucleate InP under micro-crucibles. [ABSTRACT FROM AUTHOR]

[Display omitted] Improving ligand-to-active metal charge transfer (LAMCT) by finely tuning the organic ligand is a decisive strategy to enhance charge transfer in metal organic frameworks (MOFs)-based catalysts. However, in most MOFs loaded with active metal catalysts, electron transmission encounters massive obstacle at the interface between the two constituents owing to poor LAMCT. Herein, amines (–NH 2) functionalized MOFs (NH 2 -MIL-101(Cr)) encapsulated active metal Pt nanoclusters (NCs) catalysts are synthesized by the polyol reduction method and utilized for the photoreduction of CO 2. Surprisingly, the introduction of –NH 2 (electron donating) groups within the matrix of MIL-101(Cr) improved the electron migration through the LAMCT process, fostering a synergistic interaction with Pt. The combined experimental analysis exposed the high number of metallic Pt (Pt0) in Pt@NH 2 -MIL-101(Cr) catalyst through seamless electron shuttling from N of –NH 2 group to excited Pt generating versatile hybrid Pt-N catalytic centres. Consequently, these versatile hybrid catalytic centres act as electro-nucleophilic centres, which enable the efficient and selective conversion of C O bond in CO 2 to harvest CH 4 (131.0 µmol.g−1) and maintain excellent stability and selectivity for consecutive five rounds, superior to Pt@MIL-101(Cr) and most reported catalysts. Our study verified that the precise tuning of organic ligands in MOFs immensely improves the surface-active centres, electron migration, and catalytic selectivity of the excited Pt NCs catalysts encaged inside MOFs through an improved LAMCT pathway. [ABSTRACT FROM AUTHOR]

As the hydrogen source of carbon-free fuel cells, the key to realize the green and low-energy decomposition hydrogen production process is to select materials with excellent catalytic performance for ammonia dehydrogenation. In this study, the rare earth element lanthanum (La) was doped onto the surface of Al 2 O 3 by the impregnation method. The aforementioned material was subsequently used as a new material for the synthesis of single metal Co catalysts that catalyzed ammonia decomposition. Various characterization techniques (XRD, HRTEM, N 2 physical adsorption-desorption, ICP, XPS, SEM, H 2 -TPR) were employed to investigate the relationship between the structure and performance of Co/La–Al 2 O 3 catalysts. The findings indicated that the 10Co/La(5)-Al 2 O 3 catalyst was the most active. Under the conditions of 550 °C and 9000 mL h−1·g cat −1, the conversion of ammonia reached 90 %, and the yield of hydrogen reached 8.9 mmol·g cat −1·min−1. A perovskite-type metal oxide layer of LaAlO 3 was generated on the surface of Al 2 O 3 support after doping the appropriate amount of lanthanum (5 %), which directly affects the catalytic performance of the catalyst. The small amount of LaAlO 3 optimized the strong interaction between the metal Co and the supports, thereby enhancing catalytic performance. While stabilizing the active component Co, XPS and H 2 -TPR also implied that the presence of La could enhance the electron transfer between the support and Co, as well as facilitate the desorption of nitrogen and hydrogen products, therefore, the low temperature activity of Co/La–Al 2 O 3 catalyst can be improved. The ammonia decomposition efficiency of the catalyst doped with 5 % wt La was much higher than that of the catalyst without La incorporation. The simple modified support developed by us, which loads a monoatomic Co catalyst, provides a new approach for the development of high-activity transition metal catalysts. [ABSTRACT FROM AUTHOR]