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The conversion of biomass to 5-hydroxymethylfurfural (HMF) holds substantial promise as a renewable energy source. Notably, HMF can be transformed into 2,5-bis(hydroxymethyl)furan (BHMF), a crucial reactant in biofuel production, but requires harsh operating conditions, H2, and precious metal catalysts. A recently reported Cannizzaro reaction of HMF to BHMF, characterized by its efficiency, mild conditions, and eco-friendliness, instead employed ionic liquids (ILs) to achieve high yields. In this study, combined quantum mechanical and molecular mechanical (QM/MM) simulations in conjunction with Metropolis Monte Carlo statistical mechanics and free-energy perturbation theory utilized M06-2X/6-31+G(d), PDDG/PM3, and the OPLS-VSIL force field to uncover important solute–solvent interactions present in the HMF to BHMF reaction pathway. The Cannizzaro reaction was examined in water and in five ILs composed of the 1-butyl-3-methylimidazolium [BMIM] cation coupled to hexafluorophosphate, tetrafluoroborate, thiocyanate, chloride, and bromide. Energetic and structural analysis of the rate-determining hydride transfer between HMF and the hydride-donor anion HMFOH− attributed the enhanced reactivity to highly organized solvent interactions featuring (1) hydrogen bonding between the ring protons of [BMIM] and the negatively charged carbonyl oxygen atoms on the transition structure, (2) favorable electrostatic interactions between the IL anions and solute hydroxyl groups, and (3) beneficial π–π stacking interactions between [BMIM] and the two aromatic rings present in HMF and HMFOH−. [ABSTRACT FROM AUTHOR]

Zeolitic Imidazolate Frameworks-8 (ZIF-8) is commonly used as an ideal precursor for non-noble metal catalysts because of its high specific surface area, ultra-high porosity, and N-rich content. Upon pyrolyzing ZIF-8 at 900 °C in Ar, the resulting material, referred to as Z8, displayed good activity toward the oxygen reduction reaction (ORR). Then the ZIF-8 was mixed with various conductive carbon materials, such as multiwall carbon nanotubes (MWCNTs), Acetylene black (ACET), Vulcan XC-72R (XC-72R), and Ketjenblack EC-600JD (EC-600JD), to form Z8 composites. The Z8/MWCNTs composite exhibited enhanced ORR activity owing to its network structure, meso-/microporous hierarchical porous structure, improved electrical conductivity, and graphitization. Subsequently, iron and nitrogen co-doping is achieved through the pyrolysis of a mixture comprising Fe, N precursor, and ZIF-8/MWCNTs, which is denoted as FeN-Z8/MWCNTs. The intrinsically high electrical conductivity of MWCNTs facilitated efficient electron transfer during the ORR, while the meso-/microporous hierarchical porous structure and network structure of Fe, N co-doped ZIF-8/MWCNTs promoted oxygen transport. The presence of Fe-containing species in the catalyst acted as activity centers for ORR. This strategy of preparing Z8 composites and modifying them with Fe, N co-doping offers an insightful approach to designing cost-effective electrocatalysts. [ABSTRACT FROM AUTHOR]

Surface property modification of catalyst support is a straightforward approach to optimize the performance of supported noble metal catalysts. In particular, oxygen vacancies and hydroxyl groups play significant roles in promoting noble metal dispersion on catalysts as well as catalytic stability. In this study, we developed a nanoflower-like TiO2-supported Pd catalyst that has a higher concentration of oxygen vacancies and surface hydroxyl groups compared to that of commercial anatase and P25 support. Notably, due to the distinctive structure of the nanoflower-like TiO2, our catalyst exhibited improved dispersion and stabilization of Pd species and the formation of abundant reactive oxygen species, thereby facilitating the activation of CO and O2 molecules. As a result, the catalyst showed remarkable efficiency in catalyzing the low-temperature CO oxidation reaction with a complete CO conversion at 80 °C and stability for over 100 h. [ABSTRACT FROM AUTHOR]

Atomic isolated and dispersed single atom catalyst is ideal for high-performance industrial catalyst. However, the contribution from small amounts of nanoclusters coexisting with single atoms to the catalytic reaction activity is often neglected. In this work, a MXene-supported uniformly dispersed Pt single atoms and nanoclusters (Pt 1 +Pt n /MXene) were obtained by self-assembly through an impregnation method. The catalyst exhibits high electrochemical performance in the hydrogen evolution reaction with an overpotential of only 61.3 mV and a Tafel slope of 32.5 mV dec−1 at a current density of 10 mA cm−2 in an acidic environment. The XAFS analysis and further DFT calculation indicate that the synergistic effect between single atoms and nanoclusters can facilitate adsorption of H* and promote the HER reaction. This work provides an efficient method for integrating multiple active sites in noble metal catalysts. • Constructing Pt sites on MXene enables a strong synergism between nanoclusters and single atoms. • Pt 1 +Pt n /MXene possesses large numbers of highly active Ti–O–Pt interfacial sites. • Ti–O–Pt sites make Pt 1 +Pt n /MXene obtain an outstanding catalytic performance in HER. • Pt 1 +Pt n /MXene boosts the adsorption of H* and promotes the HER reaction process. [ABSTRACT FROM AUTHOR]

Excellent oxygen evolution reaction (OER) electrocatalysts hold paramount significance for related clean energy conversion technologies. High-entropy materials have garnered significant interests because of their novel structures and unprecedented potentials in application. Herein, we successfully prepared a high-entropy metal sulfide catalyst, specifically (FeCoNiMnMo)S x , through a facile method. The resulting catalyst exhibited a phase similar to CoS 2 and its electrocatalytic activity was rigorously evaluated as an OER catalyst in 1 M KOH. Endowed by the synergistic effect and the modulation of electronic structures among the various metals, the (FeCoNiMnMo)S x catalyst demonstrated exceptional water oxidation performances. Notably, it required only 290 mV of overpotential to reach 10 mA cm−2. This remarkable performance underscores the effectiveness of high-entropy sulfides as electrocatalysts. The present work supplied a new successful example for exploring the vast potential of high-entropy materials in electrocatalysis and other related fields. A high-entropy metal sulfide (FeCoNiMnMo)S x catalyst was facilely prepared. Thanks to the synergistic effect and modulation of electronic structure between multiple metals, the catalyst exhibits excellent OER performances with only 290 mV of overpotential in 1 M KOH to reach 10 mA cm−2 of current density. [Display omitted] • High-entropy metal sulfide (FeCoNiMnMo)S x was fabricated facilely. • Co is confirmed the first important active element for OER. • Synergistic effect and modulation of electronic structure were occurred. • The (FeCoNiMnMo)S x shows excellent activity for oxygen evolution reaction. • The (FeCoNiMnMo)S x also shows robust stability. [ABSTRACT FROM AUTHOR]

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The cleavage of C−O bonds is one of the most promising strategies for lignin‐to‐chemicals conversion, which has attracted considerable attention in recent years. However, current catalytic system capable of selectively breaking C−O bonds in lignin often requires a precious metal catalyst and/or harsh conditions such as high‐pressure H2 and elevated temperatures. Herein, we report a novel protocol of paired electrolysis to effectively cleave the Cβ−O−4 bond of lignin model compounds and real lignin at room temperature and ambient pressure. For the first time, "cathodic hydrogenolysis of Cβ−O−4 linkage" and "anodic C−H/N−H cross‐coupling reaction" are paired in an undivided cell, thus the cleavage of C−O bonds and the synthesis of valuable triarylamine derivatives could be simultaneously achieved in an energy‐effective manner. This protocol features mild reaction conditions, high atom economy, remarkable yield with excellent chemoselectivity, and feasibility for large‐scale synthesis. Mechanistic studies indicate that indirect H* (chemical absorbed hydrogen) reduction instead of direct electron transfer might be the pathway for the cathodic hydrogenolysis of Cβ−O−4 linkage. [ABSTRACT FROM AUTHOR]

The hydrogen evolution reaction (HER), as a pivotal half-reaction, significantly hinders the advancement of energy conversion efficiency. Metal electrodeposition on catalysts has been demonstrated to effectively enhance the HER reactivity. Here, Ni3S2–Fe–Ni with a multilayer structure was obtained by the electrodeposition of Ni3S2 with dopants Fe/Ni, in which a number of active sites were achieved and the intrinsic conductivity of the catalyst was well improved. Elemental analyses revealed the multilayer structure consisting of Ni3S2, NiS, and Fe. The Ni3S2–Fe–Ni catalyst exhibited impressive electrochemical performance due to optimization of its structure with the overpotentials of the HER and OER of only 83 and 190 mV. Notably, at a higher current density of 100 mA cm−2, the overpotentials for the HER and OER are only 339 and 365 mV. As a bifunctional electrocatalyst, its total splitting voltage was only 1.55 V. The catalysis performance remained nearly unchanged even after 48 h of stability testing. Finally, density functional theory (DFT) calculations revealed that the potential barriers in each reaction step of the OER are evenly distributed, and optimizing the Ni3S2 structure with iron and nickel atoms reduced the reaction energy barriers during the electrochemical process, improving the OER/HER performance. [ABSTRACT FROM AUTHOR]

Compared with heavy metal catalysts, metal-free catalysts that activate persulfate (PS) for controlling organic pollutants are more economical, environmentally friendly, and safer for human health. Utilizing ZIF-8 particles as templates and polyphosphazene as the precursor, hollow N, P, and O tri-doped carbon microspheres (NPOC) with a hierarchical pore structure were successfully synthesized from ZIF-8@polyphosphazene. Their morphology and structure were investigated by SEM, TEM, TGA, XPS, BET, and FT-IR. Otherwise, NPOC were used as catalysts to activate PS for the oxidative degradation of tetracycline. The dosage of catalyst and oxidant, tetracycline concentration, carbonization temperature, and pH can all have a substantial influence on the oxidative degradation of tetracycline. Free radical testing by EPR reveals that HO˙ and SO4˙− are generated and the radical pathway is dominant in the oxidative degradation process. NPOC exhibited superior catalytic oxidation performance and good reusability, indicating their potential for application for eliminating TC from aqueous solution. [ABSTRACT FROM AUTHOR]

A [4 + 1] annulation protocol is developed for the synthesis of various 2-alkenylindole derivatives starting from aminobenzyl phosphonium salts and cinnamaldehydes. In this process, the reaction proceeds efficiently without the usage of any metal catalysts or base, and features available starting materials, a broad substrate scope, excellent yields and simple reaction conditions. [ABSTRACT FROM AUTHOR]

To understand the nature of heterogeneous catalytic processes and improve their efficiency, it is necessary to conduct both experimental and theoretical studies. At the same time, there is no unified approach to obtaining the necessary data using quantum chemistry methods. In this work, problems of the existing calculational approaches are analyzed. The obtained information is used to develop the original three‐layer embedded cluster model approach, which is shown to be the most effective. The general algorithm for obtaining such models for various oxides is formulated. The sufficient accuracy of the proposed models in predicting geometric and energy characteristics, vibrational frequencies, activation barriers, and thermodynamic characteristics is verified. The specifics of calculating the thermodynamic characteristics of heterogeneous processes using the proposed cluster models is studied in detail. The developed approach is an effective tool for studying the mechanism of heterogeneous catalytic processes both by itself and in combination with experiment. [ABSTRACT FROM AUTHOR]

In this research, we endeavour to demonstrate the potential of Aqueous Extract of Dillenia indica (AEDI) pseudosepals in catalyzing tetrahydrobenzo[b]pyran and spirooxindole derivatives, thereby paving the way for greener and more sustainable chemical synthetic strategies. The reactions proceed smoothly with AEDI as the catalyst in water at room temperature to afford high to near quantitative yields in a short duration of 15–45 minutes, making it a green and environmentally friendly alternative to existing protocols. This synthetic pathway satisfies several green chemistry principles such as avoiding the use of any toxic or hazardous metal catalyst and other external additives/promoters, the use of a biodegradable catalyst obtained from natural resources, auxiliary solvent conditions, and reusability of the catalyst. The protocol reported here offers remarkable attributes like wide substrate scope, high to near quantitative yields of products and the scale up viability along with ecological safety, straightforward work‐up procedure and excellent values of green chemistry metrics as compared to other reported approaches. [ABSTRACT FROM AUTHOR]

Electrocatalytic water decomposition couple with renewable energy is considered as a green and sustainable method for hydrogen production. However, the development of non-precious metal bifunctional catalysts remains one of the major bottlenecks in electrochemical water decomposition, hindering the key challenges for its commercial application. In this paper, we report a simple and rapid synthesis of an iron metal-organic skeleton (Fe-MOF) precursor at room temperature via the flash nanoprecipitation (FNP) technique. The precursor reacts with SiCl 4 to derive a Si-Fe-MOF catalyst with mesoporous structure. The electrochemical performance tests reveal that compared to Fe-MOF, Si-Fe-MOF exhibits significantly better performance, with overpotentials of 181 mV and 269 mV for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) respectively (while Fe-MOF has overpotentials of 297 mV for HER and 337 mV for OER) at a current density of 10 mA cm−2, and it possesses superior stability, respectively, at 10 mA cm−2, and has superior stability. Meanwhile, Si-Fe-MOF is used as a bifunctional catalyst with a full hydrolysis voltage of 1.62 V. It is found by in situ Raman spectroscopic characterization that Si-Fe-MOF is converted from Fe metal sites to more active FeOOH during the OER process. DFT calculations show that the doping of Si atoms in Si-Fe-MOF optimize the electronic structure of the catalyst and optimize the reactive intermediates' adsorption. • Si-doped Fe-MOF with improved electrolytic water performance. • The mesoporous structure of Si-Fe-MOF provides more active sites. • Revealing the formation of intermediate hydroxylated iron substances. • Silicon doping to optimize the adsorption energy of intermediates. • SiCl 4 enables silicon doping and promotes waste utilisation. [ABSTRACT FROM AUTHOR]

The key to designing energy-efficient hydrogen production systems lies in the development of highly catalytic, low-cost non-precious metal catalysts, along with the substitution of high-energy-consuming oxygen evolution reactions with reactions involving easily oxidizable small molecules at the anode. In this paper, molybdates (NiMoO 4 and CoMoO 4) that grow on nickel foam are treated with vulcanization and nitriding methods, and Mo doped Ni 3 S 2 (Mo–Ni 3 S 2) and N doped CoMoO 4 (N–CoMoO 4) are prepared, respectively. Mo–Ni 3 S 2 exhibits excellent UOR activity requiring only 1.335 V to drive 100 mA cm−2. It is found that Mo–Ni 3 S 2 participated in both of the decomposition of urea (15.4 %) to form NH 3 and the oxidation reaction of urea (84.6 %) to form N 2 to keep the anodic reaction in the low potential range, avoiding the oxidation of nickel sites in the catalyst to form NiOOH. In addition, N–CoMoO 4 catalyst exhibits excellent hydrogen evolution reaction (HER) activity requiring only 67 mV to drive 100 mA cm−2. Finally, the catalysts prepared by molybdate are used to construct urea oxidation electrolytic system. The Mo–Ni 3 S 2 (+) || N–CoMoO 4 (−) urea oxidation-assisted water splitting system requires only 1.47 V to achieve 100 mA cm−2, which is a voltage reduction of 180 mV compared to conventional water electrolysis systems. The system realizes high energy efficiency hydrogen production and urea wastewater purification. This work provides insights into the design of low-energy-consuming hydrogen production systems. [Display omitted] • The catalysts prepared by molybdate exhibit efficient UOR and HER activity. • Mo–Ni 3 S 2 follows a new UOR mechanism of urea decomposition and urea oxidation. • The Mo–Ni 3 S 2 (+) || N–CoMoO 4 (−) system requires only 1.47 V to afford 100 mA cm−2. • We couple UOR and HER to construct an energy-saving hydrogen production system. [ABSTRACT FROM AUTHOR]

Polymer electrolyte membrane fuel cells (PEMFCs) are an important enabler of the nascent hydrogen economy. However, due to the reliance on precious metal catalysts like platinum, reducing the cost and broad penetration of PEMFCs beyond vehicle application remains a challenge. In this respect, alternative non‐precious metal catalysts and other carbon‐based catalysts remain the holy grail toward advanced low‐cost PEMFC. This review summarizes recent progress along the development of non‐precious catalysts and their performance under PEMFC operation. Critical factors such as the activity, stability, and durability of non‐precious metal catalysts and their associated mechanisms including the paths leading to degradation are discussed. Ultimately, the review concludes by highlighting the impressive activity and potential of NPM catalysts and the areas of focus to enable the translation of non‐precious catalysts to commercially viable PEMFC systems. [ABSTRACT FROM AUTHOR]

A new MOF (Co‐TIST) was synthesized from 2,4,6‐tris (imidazol‐1‐yl)‐1,3,5‐s‐triazine (TIST) and cobalt nitrate. TIST was prepared from the reaction of cyanuric chloride and imidazole and used as a ligand for the formation of MOF. After characterization of Co‐TIST by different methods, we have investigated the carbonyl‐Heck cross‐coupling reaction of aldehydes with aryl halides in the presence of Co‐TIST as a new heterogeneous catalyst. Various ketones were obtained in good to high yields by this method. The reactions did not require high temperature, additives, or large amounts of the catalyst. The catalyst was recycled in five consecutive runs with unimportant decrease in its catalytic activity. Notably, this is the first report of using a MOF for the carbonyl‐Heck cross‐coupling reaction of aryl halides and aldehydes. [ABSTRACT FROM AUTHOR]

The conversion of glycerol to aromatic hydrocarbons is of great significance from the perspective of reducing dependence on fossil resources and comprehensive utilization of industrial by-products. In this study, Holl-HZSM-5 catalysts with hollow structure was prepared and then modified by Zn, Sn and La by impregnation method for the aromatization of glycerol. The results showed that the hollow structure could broaden the internal space and specific surface area of the HZSM-5, thus prolonged the lifetime. Zn modified Holl-HZSM-5 (Zn-Holl-HZSM-5(IM)) present a preferable catalytic performance: under the conditions of 40 wt% glycerol/methanol solution, reaction temperature of 400 °C at 1 atm, mass space velocity of 0.82 h−1, the yield of BTX was 33.5%, and the catalytic lifetime was 8.5 h. In addition, the different preparation methods were investigated for Zn modified Holl-HZSM-5. It was found that Zn@Holl-HZSM-5 prepared by in-situ method had suitable acid strength, acid distribution and intergranular mesoporous, thus the conversion path of aromatization could be further coordinated, leading to a better catalytic efficiency and longer lifetime. [ABSTRACT FROM AUTHOR]

The selective hydrogenation of acetylene is of industrially indispensable in the production of polymer-grade ethylene. The design of non-precious metal catalysts with outstanding performance is of pivotal importance in order to replace the supported Pd–Ag catalysts. Our previous work showed that a copper carbide (CuxC)-containing catalyst exhibited high hydrogenation activity and selectivity under mild conditions. In the present work, Mg(OH)2 was used to modify the CuxC-containing catalyst in order to improve its catalytic performance. Mg(OH)2-modified CuxC-containing catalyst was prepared from a coprecipitate of Cu(OH)2 and Mg(OH)2, which was obtained by precipitation of Cu(NO3)2 and Mg(NO3)2 solution with dropwise addition of NaOH solution, by thermal treatment in C2H2/Ar (0.5%) at 120 ℃ followed by H2 reduction at 150 ℃. The introduction of Mg(OH)2 led to reduced CuxC crystalline size and to increased amount of CuxC crystallites. In addition, the basic nature of Mg(OH)2 is favorable to suppress the undesired oligomerization. The prepared catalyst showed excellent catalytic performance with complete acetylene conversion, low selectivity to unwanted ethane (24%), and high stability at 100 °C and atmospheric pressure in the presence of large excess ethylene in 100 h. [ABSTRACT FROM AUTHOR]

The coordination environment is crucial to the electrocatalytic activity of single‐atom catalysts (SACs). Although substituting N atoms in traditional transition metal‐nitrogen (TM‐N4) configuration with other non‐metal atoms has been reported, its specific role in sulfur electrochemical reactions has not been sufficiently investigated. Herein, a Co‐P2N2 SACs configuration is fabricated to investigate the mechanistic differences compared to Co‐N4 in sulfur reduction/oxidation. This configuration enhances the electron transfer with Li2S6, where the electrons tend to aggregate between P and Li atoms as two separate parts rather than a single merged zone as observed in symmetric Co‐N4 SACs. This process facilitates polysulfide decomposition and promotes Li2S nucleation/oxidation. Furthermore, the CoPNC interlayer effectively suppresses cell self‐discharge and Li anode corrosion due to polysulfide shuttling. Li‐Li symmetrical cell incorporated with the CoPNC interlayer achieves a prolonged lifespan exceeding 1000 h, and Li‐S full cell delivers a discharge capacity of more than 1500 mAh g−1. This research provides insights into how the geometric configuration of SACs influences the performance of conversion‐type batteries. [ABSTRACT FROM AUTHOR]

Self-reconstruction of catalysts during oxygen evolution reaction (OER) is crucial for the development of energy conversion technologies. However, the relationship between the specific atomic structure of pre-catalysts and their electrocatalytic behavior after reconstruction via dual-ion leaching has not been extensively researched. In this work, we design a highly effective non-noble metal OER catalyst with heterointerface through continuous self-reconstruction of Co2(OH)3Cl@NiMoO4 as pre-catalyst by a straightforward dual-ion (i.e. MoO42− and Cl−) leaching. In-situ Raman and in-situ Fourier transform infrared (FT-IR) spectroscopy have precisely identified the progressive phase transformation of the pre-catalyst during self-reconstruction, which results in a stable heterojunction of CoOOH and NiOOH (CoOOH@NiOOH). Further calculations based on density functional theory (DFT) of CoOOH@NiOOH evident that more electrons will be aggregated in the Fermi level of Co. Notably, Gibbs free energy (ΔG) for different OER steps of CoOOH@NiOOH exhibit lower energy costs of all intermediates, implying the well catalytic properties. Ultimately, the catalyst derived from dual-ion leaching displays outstanding OER performance, characterized by an overpotential of 275 mV at a current density of 10 mA·cm−2 and exceptional stability over 12 h reaction. This work successfully paves a way of finding high-performance OER catalysts based on non-noble metal through dual-ion leaching during self-reconstruction. [ABSTRACT FROM AUTHOR]

Oxide-supported metal single-atom catalysts (SACs) have exhibited excellent catalytic performance for water–gas shift (WGS) reaction. Here, we report the single-atom catalyst Pt1/FeOx exhibits excellent medium temperature catalytic performance for WGS reactions by the density functional theory (DFT) calculations and experimental results. The calculations indicate that H2O molecules are easily dissociated at oxygen vacancies, and the formed ⋆OH and ⋆O are adsorbed on Pt1 single atoms and the adjacent O atoms, respectively. After studying four possible reaction mechanisms, it is found that the optimal WGS reaction pathway is proceeded along the carboxyl mechanism (pathway III), in which the formation of ⋆COOH intermediates can promote the stability of Pt1/FeOx SAC and the easier occurrence of WGS reaction. The energy barrier of the rate-determining step during the entire reaction cycle is only 1.16 eV, showing the high activity for the medium temperature WGS reaction on Pt1/FeOx SAC, which was verified by experimental results. Moreover, the calculated turnover frequencies (TOFs) of CO2 and H2 formation on Pt1/FeOx at 610 K (337 °C) can reach up to 1.14 × 10−3 s−1·site−1 through carboxyl mechanism. In this work, we further expand the application potential of Pt1/FeOx SAC in WGS reaction. [ABSTRACT FROM AUTHOR]

With the aim of developing efficient non-noble metal catalysts for hydrogen evolution reaction (HER), this work synthesized a Ni–Se–Lu electrocatalyst by incorporating the rare earth element Lu to modify the Ni–Se electrode. The hydrogen evolution performance of the Ni–Se–Lu electrocatalyst under alkaline conditions was investigated on the basis of the micromorphology and structure of the electrode. In 1 M KOH solution, the Ni–Se–Lu electrode exhibited small overpotentials of 52 and 105 mV at current densities of 10 and 50 mA cm−2, respectively, along with a Tafel slope of 63.8 mV·dec−1. Electrochemical analysis results revealed increased active sites and electrochemically active surface area and improved surface roughness after the introduction of Lu element. Moreover, excellent stability in hydrogen evolution was demonstrated with a potential decay rate below 5% after 72 h of electrolysis. [Display omitted] • Ni–Se–Lu/NF electrocatalyst is developed via a facile and simple galvanostatic electrodeposition method. • Ni–Se–Lu/NF electrocatalyst showed excellent HER activity with low overpotential of 52 mV at 10 mA cm−2. • The excellent HER activity can be attributed to the increased intrinsic activity and accelerated electron transfer rate. [ABSTRACT FROM AUTHOR]

Efficient non-precious metal electrocatalysts are crucial for hydrogen production through water electrolysis. Combining a superhydrophilic electrocatalyst with oxygen vacancy and a conductive carbon matrix is significant for NiFe LDH-based oxygen evolution reaction (OER) applications. In this study, NiFe LDH nanoflowers and Co-doped NiFe LDH nanoneedles were synthesized on graphite felt through an in-situ self-assembly strategy. Further results have shown that doping Co into NiFe LDH nanoarrays significantly enhances the specific surface area and oxygen vacancy density, while the graphite felt serves as a conductive scaffold and prevents active sites detachment. Oxygen vacancies in Co 3 –Ni 7 Fe 3 LDH/TGF adjust the electronic configuration, and superhydrophilicity promotes effective electrolyte diffusion. This synergy endows Co 3 –Ni 7 Fe 3 LDH/TGF with excellent OER performance, lower overpotential of 252 mV (10 mA cm−2), a Tafel slope (63.13 mV), and stability at high current densities. This research provides a new perspective for utilizing non-precious metal catalysts on carbon substrates for hydrogen production. [Display omitted] • Co–NiFe LDH was in-situ grown on graphite felt by self-assembly strategy. • Incorporating Co increases the density of oxygen vacancies in NiFe LDH. • Nanoneedle structure boosts specific surface area and provides many active sites. • Co 3 –Ni 7 Fe 3 LDH/TGF shows a low overpotential of 252 mV at 10 mA cm−2 for OER. • Superhydrophilic Co 3 –Ni 7 Fe 3 LDH/TGF shows robust stability at high current density. [ABSTRACT FROM AUTHOR]

Nickel-catalyzed C–H bond functionalization reactions provide an impressive alternative to those with noble metal catalysts due to their unique reactivity and low cost. However, the regioselective C(sp2)–H borylation reaction of arenes accomplished by nickel catalyst remains limited. We herein disclose a silyl-directed ortho C(sp2)–H borylation of substituted arenes with a Ni(cod)2/PMe3/KHMDS catalyst system. Using readily available starting materials, this protocol provides easy access to ortho-borylated benzylic hydrosilanes bearing flexible substitution patterns. These products can serve as versatile building blocks for the synthesis of sila or sila/borine heterocycles under mild conditions. Control experiments and DFT calculations suggest that a catalytic amount of base prompts the formation of Ni(II)-Bpin-ate complex, likely related to the C(sp2)–H bond activation. This borylation reaction might follow an unusual Ni(II)/Ni(IV) catalytic cycle. Nickel-catalyzed C–H bond functionalization reactions provide an impressive alternative to those with noble metal catalysts but the regioselective C(sp2)−H borylation reaction of arenes accomplished by nickel catalyst remains challenging. Here the authors disclose a silyl-directed ortho C(sp2)−H borylation of substituted arenes with a Ni(cod)2/PMe3/KHMDS catalyst system. [ABSTRACT FROM AUTHOR]

The construction of chiral motifs containing nonadjacent stereocenters in an enantio‐ and diastereoselective manner has long been a challenging task in synthetic chemistry, especially with respect to their stereodivergent synthesis. Herein, we describe a protocol that enables the enantio‐ and diastereoselective construction of 1,5/1,7‐nonadjacent tetrasubstituted stereocenters through a Pd/Cu‐cocatalyzed Heck cascade reaction. Notably, a C=C bond relay strategy involving the shift of the π‐allyl palladium intermediate was successfully applied in the asymmetric construction of 1,7‐nonadjacent stereocenters. The current method allows for the efficient preparation of chiral molecules bearing two privileged scaffolds, oxindoles and non‐natural α‐amino acids, with good functional group tolerance. The full complement of the four stereoisomers of products bearing 1,5/1,7‐nonadjacent stereocenters could be readily accessed by a simple combination of two chiral metal catalysts with different enantiomers. [ABSTRACT FROM AUTHOR]

Metal atom catalysts have been among the most important research objects due to their specific physical and chemical properties. However, precise control of the anchoring of metal atoms is still challenging to achieve. Cobalt and iridium atomic arrays formed sequentially ordered stable arrays in graphdiyne (GDY) triangular cavities depending on their intrinsic chemical properties and interactions. The success of this method was attributed to multifunctional integration of GDY, enabling selective growth from one to several atoms and various atomic densities. The bimetallic atom arrays show several advantages resulting from reducibility of acetylene bonds, space limiting effect, incomplete charge transfer between GDY and metal atoms, and sp‐C hybridized triple bond skeleton. This well‐designed system exhibits unprecedented oxygen evolution reaction (OER) performance with a mass activity of 2.6 A mgcat.−1 at a low overpotential of 300 mV, which is 216.6 times higher than the state‐of‐the‐art IrO2 catalyst, and long‐term stability. [ABSTRACT FROM AUTHOR]

Development of efficient and stable non‐noble metal catalysts applied to the catalytic transfer hydrogenation of nitroarenes under mild conditions is still challenging. Herein, we report magnetically recyclable catalysts prepared via simple two‐stage pyrolysis of Co‐MOF‐74 and melamine composites. The optimized catalyst Co@C/CNTs‐10‐700 shows excellent conversion and selectivity towards transfer hydrogenation of nitroarenes with different hydrogen donors. Its excellent stability against formic acid corrosion makes it can be used in a wide range. The excellent catalytic performance can be ascribed to the synergistic effect between carbon nanotubes and Co nanoparticles. Furthermore, the catalyst was easily recycled owing to its magnetism and reused up to ten consecutive cycles without significant loss of activity, indicating that the excellent catalytic stability holds great promise in fields of industrial application. [ABSTRACT FROM AUTHOR]

Metal single‐atom catalysts (SACs) play an essential role in small molecule related energy conversion. Metal‐organic frameworks (MOFs), which contain the highly ordered arrays of organic linkers and metal nodes, as well as the clearly defined pore structures, are considered as an ideal platform to fabricate atomically dispersed metal sites. In this review, we summarize the approaches for fabricating MOF‐based SACs by utilizing their structure characteristics. A brief discussion is also given about the feasible techniques to characterize SACs. A series of representative examples of MOF‐based SACs and their energy‐related applications, mainly in photocatalysis and electrocatalysis, are discussed. The challenges and future development opportunities of MOF‐based SACs are highlighted. [ABSTRACT FROM AUTHOR]

Tuning the interfacial structure of metal oxide substrates is an essential strategy to induce electronic structure reconstruction of supported catalysts, which is of great importance in optimizing their catalytic activities. Herein, vanadium oxides‐supported Ir catalysts (Ir‐V2O3, Ir‐VO2, and Ir‐V2O5) with different interfacial bonding environments (Ir‐V, Ir‐Obri, and Ir‐O, respectively) were investigated for hydrogen evolution reaction (HER). The regulating mechanism of the influence of different interfacial bonding environments on HER activity was investigated by both experimental results and computational evidence. Benefiting from the unique advantages of interfacial Ir‐V direct metal bonds in Ir‐V2O3, including enhanced electron transfer and electron donation ability, an optimized HER performance can be obtained with lowest overpotentials of 16 and 26 mV at 10 mA cm−2, high mass activities of 11.24 and 6.66 A mg−1, and turnover frequency values of 11.20 and 6.63 s−1, in acidic and alkaline conditions respectively. Furthermore, the assembled Ir‐V2O3||RuO2 anion exchange membrane (AEM) electrolyzer requires only 1.92 V to achieve a high current density of 500 mA cm−2 and realizes long‐term stability. This study provides essential insights into the regulating mechanism of interfacial chemical bonding in electrocatalysts and offers a new pathway to design noble metal catalysts for different applications. [ABSTRACT FROM AUTHOR]

ABSTRACT Biomimetic heterogeneous catalysts were prepared by immobilization of meso‐tetrakis(4‐carboxyphenyl)porphyrinatomanganese(III) acetate (MnTCPP) and meso‐tetrakis(4‐carboxyphenyl)porphyrinatoiron(III) chloride (FeTCPP) on graphitic carbon nitride (g‐C3N4) nanosheets. The anchored catalysts were characterized by various techniques such as scanning electron microscopy, thermogravimetric analysis, powder X‐ray diffraction, ultraviolet visible, photoluminescence, flame atomic absorption, and Fourier transform infrared spectroscopy. The thermogravimetric analysis demonstrated that the prepared catalysts were thermally stable up to almost 350°C, exhibiting high thermal stability. In the following, the catalytic efficiency of the prepared nanocatalyst was also investigated for the oxidation of various olefins with hydrogen peroxide (as a green oxidant) and the effect of various parameters which may affect the catalytic efficiency was optimized. The maximum conversion (100% for α‐methylstyrene and 97% for cyclooctene) was obtained in the presence of MnTCPP@C3N4. The Mn porphyrin nanocatalyst shows higher catalytic efficiency compared to the Fe porphyrin. [ABSTRACT FROM AUTHOR]

The metal supported catalysts are emerging catalysts that are receiving a lot of attention in CO2 hydrogenation to C1 products. Numerous experiments have demonstrated that the support (usually an oxide) is crucial for the catalytic performance. The support metal oxides are used to aid in the homogeneous dispersion of metal particles, prevent agglomeration, and control morphology owing to the metal support interaction (MSI). MSI can efficiently optimize the structural and electronic properties of catalysts and tune the conversion of key reaction intermediates involved in CO2 hydrogenation, thereby enhancing the catalytic performance. There is an increasing attention is being paid to the promotion effects in the catalytic CO2 hydrogenation process. However, a systematically understanding about the effects of MSI on CO2 hydrogenation to C1 products catalytic performance has not been fully studied yet due to the diversities in catalysts and reaction conditions. Hence, the characteristics and modes of MSI in CO2 hydrogenation to C1 products are elaborated in detail in our work. [ABSTRACT FROM AUTHOR]

Metal ion (Mn+ ${{{\rm M}}^{{\rm n}+}}$ /oxidant) and UV light catalyzed (UV/oxidant) mineralization and biodetoxification of Ponceau Xylidine (PX) was undertaken in this study. Hydrogen peroxide (HP) and ammonium persulphate (APS) were employed as oxidants and Fe2+ ${{{\rm F}{\rm e}}^{2+}}$ and Ag+ ${{{\rm A}{\rm g}}^{+}}$ as metal ion catalysts. Although highest mineralization in Fe2+ ${{{\rm F}{\rm e}}^{2+}}$ /APS and UV/HP systems was exhibited at pH 1 (63.09 %) and 3 (64.83 %), respectively, lowest was shown by Ag+ ${{{\rm A}{\rm g}}^{+}}$ /oxidant systems at any pH. The Fenton process achieved mineralization of ≈48.50 % within the pH range of 3 to 6.15. The study established Fe2+ ${{{\rm F}{\rm e}}^{2+}}$ as a better catalyst than Ag+ ${{{\rm A}{\rm g}}^{+}}$ , and HP, a better oxidant (2.5 times more effective) than APS. Mineralization with UV/HP at 120 min is highest at pH 3 (92.0 %) and 6.15 (86.17 %). Various inorganic anions were found to inhibit mineralization. The maximum and minimum inhibition was shown by Cl- ${{{\rm \ }{\rm C}{\rm l}}^{-}}$ in UV/HP and UV/APS systems respectively. The inhibition effect of NO3- ${{{\rm N}{\rm O}}_{3}^{-}}$ decreases with concentration till 0.01 mM, beyond which an increasing trend was observed. This study also demonstrates that the biodetoxification efficiency of various systems is in the order: UV/HP>UV/APS>Fe2+ ${{{\rm F}{\rm e}}^{2+}}$ /HP. Thus, UV/HP is the most suitable system for the treatment of PX, displaying a biodetoxification efficiency of 83.0 % and mineralization of 92.0 %. [ABSTRACT FROM AUTHOR]

Interparticle hydrogen spillover is the phenomenon of H migration over different catalyst particles, which should be a physical mixture of at least two solid catalysts. In this review, we analyze examples of enhanced catalysis based on interparticle (reverse) hydrogen spillover. Simple physical mixtures of powdered catalysts containing metal catalysts of H2 dissociation/recombination and solid catalysts with active sites for substrate activation significantly enhance catalytic reactions. These reactions include aromatic hydrogenation, CO2 methanation, and the deoxydehydration of polyols, aromatization of lower paraffins, and direct coupling of benzene and alkanes. The acceleration effect and proposed reaction pathway of each example involving interparticle (reverse) hydrogen spillover are summarized. Simple reaction systems comprising physical mixtures of at least two powdery solid catalysts should enable unique catalysis in the future with the aid of interparticle (reverse) hydrogen spillover. [ABSTRACT FROM AUTHOR]

To address the shortage of fossil energy, the development of affordable and efficient non-precious metal catalysts for oxygen evolution reaction (OER) from electrocatalytic water splitting is still a crucial challenge. Herein, the bimetallic NiFe metal–organic frameworks (MOFs) are synthesized by hydrothermal and electro-deposition. Benefiting from the synergistic effect of Fe and Ni, the catalyst demonstrates extraordinary activity, which exhibits favorable OER catalytic activity in 1 M KOH solution with an overpotential of 206 mV at 10 mA cm−2. Meanwhile, the obtained NiFe-NDC presents promising stability in the 20 h test at 50 mA cm−2. [ABSTRACT FROM AUTHOR]

Glycine derivatives are prevalent structural motifs that can be easily found in many bioactive molecules and natural isolates. To date, chemical synthesis of hydrazino-containing glycine derivatives has mainly focused on the utilization of metal catalysts or light-irradiation methods. Herein, we report a three-component reaction of amines, azodicarboxylates, and diazoalkanes under green and sustainable reaction conditions, leading to a wide range of hydrazino-containing glycine derivatives in good to excellent yields. Compared to the reported methods, the as-developed method does not require catalysts or light irradiation. The success of the scale-up reaction, synthetic transformation of the formed glycine products, and the direct aqueous media synthesis further rendered the method attractive and valuable. Control experiments together with detailed mechanism studies revealed that the in situ formed diaziridines are the key reaction intermediates. [ABSTRACT FROM AUTHOR]

Due to the high oxidation potential of arenes and alkenes, previous methods of benzylic and allylic C–H oxidation necessitated the use of strong oxidizing agents, metal catalysts, or free radical initiators (such as photocatalysts or hydrogen atom transfer reagents) to be effective. Herein, we employ oxygen to generate a triple-spin charge transfer state with π-conjugated compounds effectively accessing the triplet excited states of arenes, followed by energy transfer to form singlet oxygen facilitating C–H bond oxidation. Distinct from previous oxidations, it is the first time that a series of natural products and drug molecules (27 examples) are selectively oxidized without any catalysts or additives. The transformation can be implemented under sunlight to produce valuable unsaturated (aromatic) ketones and only water as waste, which meets every one of the 12 principles of green chemistry. [ABSTRACT FROM AUTHOR]

N-Substituted 5-(hydroxymethyl)-2-furfuryl amines have been obtained through the reductive amination of 5-hydroxymethylfurfural (HMF) with a variety of primary amines using a non-noble metal catalyst based on monodisperse Co nanoparticles covered by a thin carbon layer. The Co@C catalyst was highly active, selective and stable, allowing us to perform the reductive amination of HMF under very mild reaction conditions (60 °C and 4 bar H2) using ethanol as a green solvent and achieve the corresponding amino-alcohol in yields ranging from 80 to 99%. Moreover, the reaction was extended to other furanic aldehydes with excellent success. Furthermore, in order to synthesize amino-ester derivatives, precursors of ammonium salt-based surfactants, the reductive amination of HMF with methylamine was coupled with the selective esterification of the hydroxymethyl group of the furan ring with fatty acids using lipase CALB (Novozym 435) as a biocatalyst in 2-methyltetrahydrofuran as a green and enzyme compatible solvent, achieving practically total conversion to the corresponding amino-esters. The process was implemented in flow reactors by combining two consecutive fixed bed reactors, achieving a global yield of the amino-ester derivative of 85%, which was maintained over 86 h of operation. [ABSTRACT FROM AUTHOR]

It is key to develop novel economical and effective non-noble metal bifunctional catalysts for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in water splitting cells. Herein, a series of novel two-dimensional (2D) ultrathin donor-acceptor Co-based metal organic framework nanoplates (U-DA-CoMOF-NPs) as bifunctional HER/OER catalysts have been designed and fabricated based on a donor-acceptor strategy. Density functional theory calculations demonstrate that the fabricated U-DA-CoMOF-NPs are fine donor-acceptor pairs having HOMO-LUMO localizations and a HOMO-LUMO gap of 2.60 eV and give the Gibbs free energy for a reasonable OER mechanism. Additionally, changes in anions can affect the physicochemical characterizations and HER/OER performance of the fabricated U-DA-CoMOF-NPs. As a result, the fabricated U-DA-CoMOF-NPs-1 using NO 3 − as an anion exhibits the optimal HER/OER performance in alkaline solution thanks to the thinnest nanoplate thickness, the largest surface area and hierarchical mesoporous structure. Moreover, a self-assembled overall water splitting cell with U-DA-CoMOF-NPs-1/NF as both cathode and anode achieves a low potential of 1.65 V and a high cycling stability at 10 mA cm−2 for at least 15 h. The present study offers an option to design and fabricate other cost-effective donor-acceptor MOF-based catalysts for water splitting cells. • A series of U-DA-CoMOF-NPs have been fabricated with a donor-acceptor strategy. • The HOMO positioning is on Tdc, LUMO localization is at Tpt and a gap is 2.6 eV. • Co–N has more positive catalytic ability for OER than pyridinic-N and thiophene-S. • The representative U-DA-CoMOF-NPs-1 exhibits the optimal HER/OER performance. • A U-DA-CoMOF-NPs-1/NF cell shows a low potential and high stability at 10 mA cm−2. [ABSTRACT FROM AUTHOR]

The electronic structure of molybdenum carbide closely resembles that of Pt, making it a promising candidate material for replacing noble metal catalysts. However, the primary challenge is the controlled and eco-friendly synthesis of molybdenum carbide. Herein, we developed a sustainable and controlled method for synthesizing a heterostructure catalyst for the electrocatalytic hydrogen evolution reaction (HER) using starch as the raw material. Through a hydrothermal redox reaction and subsequent temperature-programmed treatment under an inert atmosphere, the hexagonal Mo 2 C-cubic MoC heterostructure nanoparticles were dispersed on a carbon matrix. Our investigation into the synthesis process extensively covered the growth of MoO 2 nanocrystals and hydrochar during the hydrothermal redox reaction, as well as the phase evolution during the subsequent temperature-programmed treatment. Electrochemical assessments demonstrated the catalyst's remarkable efficiency for the hydrogen evolution reaction across both acidic and alkaline media, achieving a current density of 10 mA/cm2 with an overpotential of 139.4 mV in 1 M KOH solution and 160.7 mV in 0.5 M H 2 SO 4 solution. Combining a series of electrochemical characterizations and applying the distribution of relaxation times (DRT) analysis to operando electrochemical impedance spectroscopy (EIS) data, the superior kinetic performance of the Mo 2 C–MoC/C was demonstrated, outperforming that of single-phase molybdenum carbide. Furthermore, the catalyst has demonstrated remarkable stability even at high current densities in both acidic and alkaline electrolytes, underscoring its potential as a cathode catalyst in both alkaline water electrolyzers and proton exchange membrane (PEM) electrolyzers. Hexagonal Mo 2 C-cubic MoC heterostructure is fabricated as a high performance electrocatalyst for hydrogen evolution. This work underscores the significance of the precise synthesis of multi-phase catalysts. [Display omitted] • Starch-derived nanoscale molybdenum carbide heterostructure. • Systematic study of the synthesis process of the catalyst. • Excellent catalytic activity and stability under acidic and alkaline media. • DRT analysis visually reveals the catalyst's superior HER kinetics. [ABSTRACT FROM AUTHOR]

Developing stable, highly active, and economical non-precious metal catalysts for the oxygen evolution reaction (OER) has been highly demanded in the new energy field since it can meet the industrial demands of large-scale electrocatalytic water splitting. A novel FeP/Ni 2 P/Fe 0.64 Ni 0.36 /C (FeNiP–FeNi–C) nanofiber was prepared by electrospinning and high-temperature phosphating. Notably, the good dispersion of FeP, Ni 2 P, and FeNi alloy nanoparticles in the nanocarbon fiber greatly increased the number of electroactive sites, and the synergistic effect between the FeP/Ni 2 P heterogeneous interface and FeNi alloy significantly improved the inherent activity of each site. Moreover, the carbon nanofibers enhanced the long-term durability of the catalyst by preventing the corrosion of the FeP, Ni 2 P, and FeNi alloy particles. Therefore, the optimal FeNiP–FeNi–C catalyst revealed exceptionally high OER activity, with overpotentials of 364 mV and 236 mV at 50 mA cm−2 and 10 mA cm−2 respectively, and the slope of Tafel of 61.00 mV·dec−1. This catalyst performs significantly better than commercial RuO 2 catalysts in alkaline electrolytes. The results of this study offer a novel perspective for the mass production of non-precious metal OER high-efficiency electrocatalysts. [Display omitted] • Novel FeNiP–FeNi–C nanofiber. • Facile and highly efficient synthesis method based on electrospinning. • High efficient electrocatalyst for oxygen evolution in water splitting. • Mechanism for improved electrocatalytic activity. [ABSTRACT FROM AUTHOR]

Enhancing the hydrolysis reaction of NaBH 4 for efficient hydrogen production requires the development of effective catalysts. In this study, the solution particles used for nanoparticles synthesized using the ultrasonic spray (US) method were produced for the first time in N 2 at room temperature in the gas and liquid intermediate phases. It also brings a new approach to synthesizing low-cost and efficient catalysts using ultrasonic spray technology. The proposed method involves US the CoCl 2 solution into the NaBH 4 solution to reduce cobalt, producing catalysts for hydrogenation. This innovative approach pioneers a gas-liquid interface reaction for metal reduction. The resulting catalysts were characterized using SEM, XRD, XPS, TEM, BET and FT-IR analysis. The influence of NaOH/NaBH 4 concentration, solution temperature, and catalyst amount on hydrogen production rate was investigated, and kinetic parameters were analyzed to understand the reaction kinetics better. The hydrogen production rates of US-Co and reduction method (RM) Co catalysts under the same conditions were calculated as 3995 ml H2 /min.g cat and 1245 ml H2 /min.g cat , respectively. The activation energy values calculated for the NaBH 4 hydrolysis of the US-Co catalyst using the nth-order and Langmuir-Hinshelwood kinetic models are 46.75 kJ/mol and 46.87 kJ/mol, respectively. Therefore, it can be concluded that the Langmuir-Hinshelwood kinetic model is consistent with the nth-order kinetic model. Experimental results showed that the ultrasonic spray method is very effective in producing active metal catalysts, offering promising opportunities for catalytic advances. [Display omitted] • A novel method of ultrasonic spray was improved for Co NPs pioneering a gas and liquid interface reaction. • The US-Co is highly active for NaBH 4 with an H 2 production rate of 3995 ml H2 /min.g cat at 30 °C. • The activation energy was calculated to be 46.75 kJ/mol with US-Co NPs. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: An efficient electrochemical approach has been developed for the construction of 3‐sulfanylquinoline derivatives by treating phenylethynylbenzoxazinanones with disulfides in an undivided cell. The protocol provided a convenient route to functionalized quinolines with good functional group tolerance. Moreover, it does not require any metal catalysts or additives, furnishing a series of biological quinolines in moderate to good yields. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: An alkyl radical initiated cyclization/tandem reaction of alkyl bromides and alkyl electrophiles by using potassium metabisulphite (K2S2O5) as a connector is developed for the synthesis of various lactam‐substituted alkyl sulfones. Notably, this process does not require a metal catalyst or metal powder reductant, highlighting its environmentally friendly features. The reaction demonstrates outstanding substrate adaptability and a high tolerance towards diverse functional groups. Furthermore, the biologically active molecules and commercially available drugs with a late‐stage modification are also highly compatible with this transformation. Mechanistic studies revealed that the reaction proceeds through a single‐step process involving intramolecular radical cyclization, "SO2" insertion, and external alkyl incorporation. [ABSTRACT FROM AUTHOR]

Fe-modified Cu catalysts with CeO2 support, prepared by the impregnation method, were subjected to physicochemical analysis and catalytic tests in the steam reforming of methanol (SRM). Physicochemical studies of the catalysts were carried out using the XRF, TEM, STEM-EDS, XRD, TPR and nitrogen adsorption/desorption methods. XRD, TEM studies and catalytic tests of the catalysts were carried out at two reduction temperatures, 260 °C and 400 °C, to determine the relationship between the form and oxidation state of the active phase of the catalysts and the catalytic properties of these systems in the SRM. Additionally, the catalysts after the reaction were analysed for the changes in the structure and morphology using TEM methods. The presented results show that the composition of the catalysts, morphology, structure, form and oxidation state of the Cu and Fe active metals in the catalysts and the reaction temperature significantly impact their activity, selectivity and stability in the SRM process. The gradual deactivation of the studied catalysts under SRM conditions could result from the forming of carbon deposits and/or the gradual oxidation of the copper and iron phases under the reaction conditions. [ABSTRACT FROM AUTHOR]

4-(2-furyl)-3-buten-2-one (FAc) is obtained by aldol condensation of furfural and acetone and has been used in hydrodeoxygenation reactions to obtain fuel products using noble metal catalysts. The hydrogenation of FAc in the aqueous phase using metallic- and Re oxide-supported catalysts on graphite was studied, within a temperature range of 200–240 °C, in a batch reactor over a 6 h reaction period. The catalysts were characterized using N2 adsorption–desorption, TPR-H2, TPD-NH3, XRD, and XPS analyses. Catalytic reactions revealed that metallic rhenium and rhenium oxide-supported catalysts are active for the hydrogenation and Piancatelli rearrangement of FAc. Notably, metallic rhenium exhibited a fourfold higher initial rate than rhenium oxide, which was attributed to the higher dispersion of Re in the Re/G catalyst over graphite. Re/G and ReOx/G catalysts tended to rearrange and hydrogenate FAc to 2-(2-oxopropyl)cyclopenta-1-one in water. [ABSTRACT FROM AUTHOR]

Efficient hydrogen storage and transportation are crucial for the sustainable development of human society. Ammonia, with a hydrogen storage density of up to 17.6 wt%, is considered an ideal energy carrier for large-scale hydrogen storage and has great potential for development and application in the "hydrogen economy". However, achieving ammonia decomposition to hydrogen under mild conditions is challenging, and therefore, the development of suitable catalysts is essential. Metal oxide-based catalysts are commonly used in the industry. This paper presents a comprehensive review of single and composite metal oxide catalysts for ammonia decomposition catalysis. The focus is on analyzing the conformational relationships and interactions between metal oxide carriers and active metal sites. The aim is to develop new and efficient metal oxide-based catalysts for large-scale green ammonia decomposition. [ABSTRACT FROM AUTHOR]

Introducing interstitial light atoms shows great potential in improving the intrinsic activity and stability of metal catalysts owing to strongly affecting the electronic structure and adsorption properties. However, filling atomically dispersed light atoms into metal lattices and further unveiling their interstitial effects are still limited by tightly arranged metal lattices. Herein, the study reports a calcination reduction assisted trace light atoms filling strategy to form a series of interstitial light single atoms filled Co‐based catalysts (Co‐X@NF, X = P, N and NF = nickel foam), therefore constructing monometallic atomic interfaces between P‐coordinated Coδ+ and Co0 to promote alkaline hydrogen evolution reaction (HER). Noteworthy, the optimal Co‐P0.43@NF with rich monometallic atomic interfacial structure shows very high turnover frequency values (5.64 s−1), which is close to noble metal level and far exceeds non‐noble metal catalysts. Meanwhile, it maintains excellent stability of 150 h at 100 mA cm−2. Theoretical studies prove that P‐coordinated Coδ+ promotes H2O dissociation and Co0 optimizes H* adsorption energy, thus forming highly active monometallic atomic interfaces, which greatly accelerates the alkaline HER kinetics. [ABSTRACT FROM AUTHOR]

Green and sustainable energy alternatives to replace fossil fuels are a topic of research in scientific community, thus yielding pursuit of advancing renewable energy systems with hydrogen emerging as a suitable and viable alternative. Efficient and non‐precious metal catalysts are crucial for large‐scale electrochemical water splitting yielding clean H2. Here, a novel two‐step hydrothermal synthesis approach to fabricate manganese–cobalt selenide nano‐cubes grown directly on nickel foam (NF) (MnCo2Se4/NF) is adopted. Leveraging its hierarchically structured architecture, augmented active sites, and electrochemically active surface area, MnCo2Se4/NF material demonstrates exceptional electrocatalytic performance for both water oxidation and reduction. With an overpotential of 233 mV for oxygen evolution reaction (OER) and 187 mV for hydrogen evolution reaction at a current density of 10 mA/cm2, MnCo2Se4/NF also exhibits a Tafel slope of 44 mV/dec for sluggish OER process. Notably, this nanocrystalline catalyst displays enhanced catalytic activity under alkaline conditions, accelerates water dissociation, and maintains good stability over 50 h. Outperforming state‐of‐the‐art RuO2, particularly in two‐electrode assemblies with an overpotential of 218 mV at 10 mA/cm2, this work offers a promising pathway for designing and manufacturing of innovative bifunctional electrocatalysts for efficient water splitting processes, thereby contributing to broader goal of sustainable energy production. [ABSTRACT FROM AUTHOR]

The nanoconfinement approach for constructing ultra‐small nanoparticles has been effectively utilized in the development of non‐precious metal catalysts. Herein, the catalyst precursor was prepared by host‐guest assembly method, using PCN‐222 as the host and 1,1′‐bis(diphenylphosphino) ferrocene (DPPF) as the guest. After calcination, the sub‐2 nm iron oxide nanoparticles within a phosphorus‐nitrogen co‐doped carbon matrix (Fe3O4@P/N‐CDCM) was obtained. Benefiting from the nanoconfinement effect, the sub‐2 nm Fe3O4 nanoparticles were uniformly dispersed on the P/N‐CDCM matrix. As a representative application, Fe3O4@P/N‐CDCM‐600 showed remarkable catalytic activity in the reduction of various nitroaromatic compounds. Under ambient conditions, the efficient reduction of nitro compounds in aqueous solution led to excellent conversion rates (96–99 %) and selectivity (99 %) within 45 minutes. Additionally, the catalyst maintained high efficiency over 5 cycles without experiencing a noticeable decrease in activity. This work provides an innovative and cost‐effective strategy for fabricating highly dispersed non‐precious metal nanoparticles. [ABSTRACT FROM AUTHOR]

Plastic pollution is an emerging global threat due to lack of effective methods for transforming waste plastics into useful resources. Here, we demonstrate a direct oxidative upcycling of polyethylene into high‐value and high‐volume saturated dicarboxylic acids in high carbon yield of 85.9 % in which the carbon yield of long chain dicarboxylic (C10‐C20) acids can reach 58.9% over cobalt‐doped MCM‐41 molecular sieves, in the absence of any solvent or precious metal catalyst. The distribution of the dicarboxylic acids can be controllably adjusted from short‐chain (C4‐C10) to long‐chain ones (C10‐C20) through changing cobalt loading of MCM‐41 under nanoconfinement. Highly and sparsely dispersed cobalt along with confined space of mesoporous structure enables complete degradation of polyethylene and high selectivity of dicarboxylic acid in mild condition. So far, this is the first report on highly selective one‐step preparation of long chain dicarboxylic acids. The approach provides an attractive solution to tackle plastic pollution and a promising alternative route to long chain diacids. [ABSTRACT FROM AUTHOR]