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An effective nonmetal F‐doped Co3O4 (F‐Co3O4) catalyst was prepared using co‐precipitation method, and its catalytic performance was investigated for N2O decomposition comparing with pure Co3O4 catalyst. The catalytic activity test indicates that F‐Co3O4 catalyst exhibits better activity with 100% N2O conversion at a reaction temperature of 380 °C, which is 80 °C lower than that of pure Co3O4. The characterization results show that F is successfully doped into the lattice of Co3O4 and replaces part of O sites, which enlarges the surface area, enhances the surface basicity, and leads to higher basic sites density on the surface of Co3O4. Moreover, F doping promotes the electron donation capacity of Co2+, weakening of Co─O bond and generation of more oxygen vacancies. The synergy of the above factors results in reduction of activation energy over F‐Co3O4 catalyst, thus F‐Co3O4 catalyst exhibits better catalytic performance than pure Co3O4 for N2O decomposition, even in the existence of O2 or H2O as impurity gas. Meanwhile, F‐Co3O4 catalyst also exhibits better stability than pure Co3O4. This work will provide practical reference for constructing efficient nonmetal‐doped Co3O4 catalysts for N2O decomposition. [ABSTRACT FROM AUTHOR]

Pd‐based catalysts supported on cerium–zirconium (CZ) oxygen storage materials (OSM) have emerged as promising candidates for the catalytic oxidation of CH4 and CO. However, achieving efficient and stable treatment of CH4 and CO in exhaust gases with Pd‐based catalysts remains a long‐term challenge. To address this, we propose a straightforward strategy of doping the supports with Cu to enhance the catalytic performance of Pd/Ce0.4Zr0.5La0.1O1.95 catalysts. Performance tests revealed that the catalytic activity of the Cu‐doped catalysts significantly improved, with T90 (CH4) decreasing from 418–301 °C and T90 (CO) decreasing from 141–113 °C. Notably, the copper‐doped catalysts exhibited enhanced water and sulfur resistance while maintaining excellent thermal stability. The CO conversion decreased by less than 2 % after a thermal deactivation experiment lasting over 100 hours. The reduction in particle size and the increase in specific surface area due to copper doping are key factors contributing to the improved total oxygen storage capacity (OSC). The main reasons for the increase in total OSC are likely the reduced particle size and increased specific surface area. [ABSTRACT FROM AUTHOR]

γ‐Butyrolactone (GBL) is a crucial product derived from the hydrogenation of maleic anhydride (MA). This study synthesized a Cu@Silicalite‐1 (Cu@S1) catalyst with 20 % Cu loading through a combination of impregnation and solid‐phase synthesis methods. The impact of Cu and Silicalite‐1 zeolite binding techniques on the MA hydrogenation was systematically investigated. The results show MA conversion of 96.2 % and GBL selectivity of 27.6 % at 240 °C, with sustained catalytic activity even after 150 hours of propionic acid corrosion on the Cu@S1 catalyst. The Silicalite‐1 zeolite plays a pivotal role in enhancing MA selective hydrogenation over Cu‐based catalysts, improving GBL selectivity, and minimizing the formation of propionic acid by‐products. The encapsulation of Cu particles by Silicalite‐1 zeolite facilitates improved dispersion of the metal and enhanced adsorption of reactants, thereby serving as a valuable catalyst for enhancing the acid and water resistance in GBL production. [ABSTRACT FROM AUTHOR]

MXene have found extensive applications in various fields, including catalysis. Two predominant roles of MXene in catalysis are as catalyst carriers or as catalysts themselves. The former has received significant attention and is addressed in other publications. This review assesses MXene and its derivatives as direct catalysts, which is particularly intriguing due to its potential to reduce the design cost of catalysts. Moreover, an in‐depth discussion of this aspect aids in understanding the true role of MXene in catalysis, beyond its role as a catalyst carrier. For instance, MXene and its derivatives have been extensively employed as photocatalysts, with their catalytic activity significantly influenced by their structural characteristics. Furthermore, due to MXene's remarkable light absorption capacity, it is crucial to explore the contributions of photothermal generation or photocatalytic‐thermocatalytic synergistic effects. Additionally, MXene has demonstrated remarkable electrocatalytic performance in hydrogen production. Moreover, MXene exhibits promising applications in thermal catalysis, such as dehydrogenation and oxidation. A deeper understanding of these aspects can help researchers further design MXene‐based nanomaterials, or alleviate their oxidation. Finally, we offer insights into the future research directions of MXene from our perspective. This review could provide guidance for the design of novel MXene catalysts for industrial applications. [ABSTRACT FROM AUTHOR]

Thermocatalytic conversions of carbon dioxide (CO2) to value‐added products offer promising approaches to achieving net negative emissions. The catalysts for CO2 conversions, particularly for CO2 hydrogenation reactions, usually involve more than one catalytic sites working together. In this review, we first introduce the advanced characterization techniques used to identify the catalytic sites in CO2 hydrogenation catalysts, sites for hydrogen (H2) activation and CO2 adsorption/activation. We then discuss how the dual or multiple‐site configurations influence the catalytic activity and selectivity in reactions such as reverse water‐gas shift (RWGS), CO2 methanation, and CO2 hydrogenation for methanol (MeOH). We finally explain the Catalytic Sites Contiguity (CSC) concept that our research group developed from the work in CO2 reforming of methane and use it to understand the relationship between the spatial arrangement of catalytic sites and the efficiency of reactant activation and conversion in recent publications on MeOH synthesis from CO2 hydrogenation. We hope our insights into the impact of CSC on catalytic performance lead to a potential top‐down design method in optimizing the CO2 hydrogenation catalysts. [ABSTRACT FROM AUTHOR]

A facile synthetic strategy is reported to afford bioactive quinazolinones and aromatic amines by employing amorphous cobalt hollow nanospheres (Co HNS) derived from a Bio‐MOF, cobalt adeninate, as a catalyst. Modulated electron states of the amorphous cobalt with a high concentration of surficial active sites and Co–N sites enhance the intrinsic catalytic activity while the support, activated carbon, facilitates the formation of hollow structure. [ABSTRACT FROM AUTHOR]

Optimizing the structural configurations of atom‐efficient single‐atom catalysts (SACs) is crucial for enhancing the catalytic performance. In this study, we used density functional theory (DFT) to investigate single Pt atoms positioned at step‐edges and within a solid solution on the CeO2(111) surface, comparing their thermodynamic stability, electronic properties, and potential energy surfaces for CO oxidation. Stability studies indicate that the solid solution catalyst is more stable than the step‐edge‐supported catalyst. Additionally, the Pt atom in the solid solution effectively activates lattice oxygen, facilitating oxygen vacancy formation. CO oxidation, analysed through the Mars‐van Krevelen mechanism, reveals that the solid solution catalyst possesses moderate CO adsorption energy and lower oxygen vacancy formation energy, resulting in reduced energy barriers throughout the CO oxidation cycle. These findings underscore the critical impact of Pt atom configuration within the CeO2 matrix on catalytic activity, with the solid solution model demonstrating superior efficiency over step‐edge‐supported Pt catalysts. [ABSTRACT FROM AUTHOR]

This review systematically evaluates the research and applications of metal mesh‐based catalysts for CO oxidation. CO is a hazardous gas that affects human health and the environment. Traditional cordierite‐based catalysts have drawbacks such as complex preparation, high costs, poor stability, and limited catalytic activity, necessitating exploration of alternative solutions. Monolithic metal mesh‐based catalysts, using metal substrates like Ti, Cu, Fe, FeCrAl, stainless steel, Al and Ni, could address these problems effectively. Generally, each metal mesh requires specific pretreatments to roughen surface and facilitate the loading of active species. Plasma electrolytic oxidation is particularly effective for Ti and Al mesh. This results in a monolithic metal mesh‐based catalyst with uniform surface distribution and fully exposed active species. The review also summarizes in‐situ preparation strategies for metal mesh‐based catalysts and their progress in CO oxidation. Finally, the development potential of metal mesh‐based catalysts is discussed, emphasizing the significant challenges and future prospects for industrial applications. [ABSTRACT FROM AUTHOR]

Metal single‐atom catalysts (SACs) have emerged as a promising class of catalysts in various fields, owing to their well‐defined active centers, tunable coordination environments, and high reaction selectivity. Among the diverse supports, graphene‐based SACs have garnered significant attention due to their exceptional properties in hydrogenation reactions. This review elucidates recent advancements in theoretical investigations of the electronic and geometric structures of metal SACs, with a focus on modulation strategies such as coordination number adjustment, heteroatom doping, defect site engineering, and frustrated Lewis pair construction. This review emphasizes atomic‐level insights into the hydrogenation reaction mechanism in thermocatalysis, including the activation of the H‐source molecules, hydrogen diffusion, and elementary reaction steps. Strategies for modulating the catalytic activity of SACs are summarized. Lastly, this review offers perspectives on the design of effective graphene‐based SACs from theoretical standpoint, paving the way for future research in this exciting field. [ABSTRACT FROM AUTHOR]

High‐entropy oxides (HEOs), known for their excellent thermodynamic stability due to their high‐entropy effect. In this study, high‐entropy (NixAlCoCrMn)3O4 oxides of spinel structure were synthesized by sol‐gel method. This HEO has a self‐reconfiguration properties in the reaction, and its internal Ni and Co ions exsolve to form a uniformly dispersed NiCo alloy on the surface. The increase of Ni content promotes the exsolution of Ni and Co ions from the interior of the spinel. The high‐entropy with a large number of oxygen vacancies not only possesses a stable structure to limit the migration of NiCo alloys, but also enhances the hydrogen overflow. In the CO methanation reaction, it has 99 % CO conversion with 87 % methane selectivity within 400 °C, and it is stable in the long‐term test. This work provides a new idea for exploring the use of high‐entropy materials to improve thermal catalytic activity and stability. [ABSTRACT FROM AUTHOR]

A heterogeneous zirconium catalyst was grafted on a ceria‐coated silica support, denoted as Zr(OEt)x/CeO2/SiO2. It exhibited higher catalytic activity compared to its homogeneous counterpart, Zr(OEt)4, in the conversion of carbon dioxide to diethyl carbonate using tetraethyl orthosilicate as a regenerable agent in the absence of any dehydrating agents under non‐protic conditions. We found that the ceria‐coated silica (CeO2/SiO2) support not only improved the catalytic activity of Zr(OEt)4 but also inhibited catalyst deactivation during catalyst recycling tests. Furthermore, we analyzed the surface of the Zr(OEt)x/CeO2/SiO2 catalysts by FE‐SEM and EDX. [ABSTRACT FROM AUTHOR]

Herein, we have developed LaMnO3 (LMO) perovskite‐based electrocatalysts of oxygen reduction and oxygen evolution reactions (ORR and OER) in a basic aqueous solution. Mechanochemical grinding and thermal annealing leads to highly‐pure perovskites as shown by X‐ray diffraction. This methodology also allows doping the LMO perovskite with RuO2, thus improving its catalytic activity, especially the oxygen evolution reaction. ORR have been analyzed by rotating ring‐disk electrode (RRDE). Eventually, these catalysts are employed in Zn/air batteries resulting in specific capacity values of 12.76 Ahg−1 at 1 Ag−1, when LMO‐RuO2 (LMO−Ru) was used as catalyst in the positive electrodes. Besides, high operational stability of Zn/air batteries for over 100 cycles was obtained, saving 1.46 mWh per cycle when LMO−Ru was used with respect to pure LMO. [ABSTRACT FROM AUTHOR]

Thiolate‐protected Au nanoclusters (NCs) have developed as a promising class of model catalysts to achieve fundamental understanding of metal nanocatalysis. Whereas, the packing mode of peripheral ligand on metal core is changeful in the reaction medium and show elusive impact on catalytic activity. In this work, using glutathione (GSH) protected Au NCs (Au@GSH NCs) with aggregation‐induced‐emission (AIE) characteristics as model catalyst for the hydrogenation of 4‐nitrophenol (4‐NP), photoluminescence (PL) intensity correlated catalytic activity of Au@GSH NCs was successfully mediated by the addition of Ag+ in the preparation or poor solvent in the reaction medium, showing a relationship of “as one falls, another rises.” Au NCs with intense PL implied a dense packing of peripheral ligand, which hampered the accessibility of active site and thus exhibited slowest catalytic reaction kinetics of the reduction of 4‐NP and vice versa. Based on this methodology, a case study of the effect of salt additives on the catalytic activity is carried out, different mechanisms are distinguished by the change in the PL intensity, and with the combination of diagnostic deuterium isotope experiments, it has been demonstrated that the proton from water solvent is involved in the reaction and that the proton transfer process is the rate‐determining step, the contribution of ionic additives to the hydrogen bonding network determines their effect on the reaction kinetics. The correlation between PL intensity and catalytic activity of Au NCs could provide an efficient way to design highly active Au NC catalysts and give a new insight to understand the unique optoelectronic properties of Au NCs and reaction mechanism. [ABSTRACT FROM AUTHOR]

Dry reforming of methane (DRM) is a promising catalytic process for converting greenhouse gases (CH4 and CO2) into syngas (CO and H2). This study investigates DRM under moderate conditions (550 °C) using supported low‐loading (0.05 wt%) metal (M) catalysts (M = Rh, Ru, Pt, Pd, Ir, Au, and Ni). The reaction was carried out for 6 h with a flow rate of 30 mL/min for both CH4 and CO2, using 0.10 g of catalyst. Among these catalysts, 0.05 wt% Rh/Al2O3 exhibited the highest DRM activity. The effect of catalyst supports revealed that Al2O3 is the most effective support for 0.05 wt% Rh. The DRM activity of Rh species supported on Al2O3 and SiO2 was compared, and the Rh species on Al2O3 outperformed those on SiO2, indicating Al2O3 enhances the DRM activity of Rh. When comparing the DRM activity of Rh nanoparticles and Rh single atoms, it was suggested that Rh nanoparticles might exhibit superior performance for DRM. Coke deposited on 0.05 wt% Rh/Al2O3 is removed by CO2, maintaining stable catalytic activity. These findings provide valuable insights into the design of catalysts that minimize the use of noble metals in DRM reactions. [ABSTRACT FROM AUTHOR]

The use of catalase (CAT) from bovine liver as an electrocatalyst in the air electrode of a primary zinc–air battery (ZAB) with neutral electrolyte (pH 7.4) is reported. First, the use of Nafion for immobilizing CAT onto electrode surface allowed to obtain long‐term stability of the catalytic activity of CAT. Besides, analysis of the CAT and CAT‐Nafion as catalysts for oxygen reduction reaction (ORR) was carried out by linear sweep voltammetry (LSV) using a rotating ring‐disk electrode (RRDE), demonstrating a four‐electron ORR mechanism. Finally, CAT and CAT‐Nafion were tested as air electrodes in flooded ZAB and compared against human hemoglobin‐based ZAB. Our results demonstrated the significant influence of the protein coating of the heme groups on the ZAB performance, affecting greatly the discharge capacity and the power density. [ABSTRACT FROM AUTHOR]

The shape‐defined ZnFe2O4 spinel with cubic and octahedral morphology was hydrothermally synthesized, respectively, and used as catalyst precursor for Fischer–Tropsch synthesis (FTS). The structure of ZnFe2O4 spinel was changed to ZnO and Fe5C2 (Fe5C2/ZnO) after reduction and carbonization. Interestingly, ZnFe2O4 with cubic morphology exhibited much higher catalytic activity and selectivity toward low‐carbon olefins (C2–C4) than the octahedral one under identical conditions, and the latter tended to produce the saturated alkanes. The primary properties of ZnFe2O4 materials before and after reduction were systematically studied through a series of characteristic technologies to reveal the difference in catalytic performance between the two ZnFe2O4 spinels with different morphologies. [ABSTRACT FROM AUTHOR]

Cyclic organic carbonates are defined as key compounds for a sustainable chemical economy. Their synthesis from CO2 under mild conditions is a useful way to valorise this greenhouse gas as carbon source. Even if a wide range of catalysts were described to promote the carbon dioxide cycloaddition into epoxides, only few ones concern enzymatic systems. The zinc–l‐histidine active site of carbonic anhydrase inspired the present work, pointing out that the imidazole moiety of the amino acid ligand has a crucial role. An extensive study was undertaken to establish the structure–activity relationship of imidazole derivatives, zinc salts, and their respective catalytic activity in the CO2 cycloaddition reaction. The effect of aromatic, alkyl, or iodine substituents and their position in N‐heterocycles were highlighted. A synergic effect was noted when combining imidazole compounds with zinc salts. The optimization of reaction conditions emphasised the in situ ZnI2–1‐methylimidazole catalytic system, which is selective toward cyclic styrene carbonates and efficient under solvent‐free mild conditions (50 °C, atmospheric CO2 pressure). Once reusing tests confirmed the catalytic system robustness, the reaction scope was enlarged to several epoxides resulting in 84%–99% yields of their corresponding cyclic carbonates. [ABSTRACT FROM AUTHOR]

The influence of the support on the performance of Mo nitrides has been investigated in ammonia synthesis and decomposition. A series of Mo–N catalysts supported on different materials, namely SiO2 (commercial, SBA‐15), Al2O3, and CeO2, were prepared. The results indicated that, despite the high dispersion of Mo species in all catalysts, large disparities in the activity for ammonia synthesis exist. Initial rates of ∼1208, ∼481, and ∼372 µmol gactive phase−1 h−1 are obtained over 10‐Mo–N/SBA‐15, 10‐Mo–N/SiO2, and 10‐Mo–N/Al2O3 respectively. However, no catalytic activity was registered when Mo species were supported on CeO2. Furthermore, 10‐Mo–N/Al2O3 deactivated after few hours of reaction. The surface composition was studied by means of XPS to probe the origin of the catalytic activity differences, and the results indicated that a range of various oxidation states of Mo was detected depending on the support. The difference in catalytic behavior could not be solely explained by the differences in Mo–N species concentrations. In situ EPR analysis exhibited that the mechanism of MoO3 nitridation could differ depending on the support, leading to the formation of different Mo–N species. The effect of support was, however, not as severe in ammonia decomposition as it was the case of ammonia synthesis. [ABSTRACT FROM AUTHOR]

Alloying and solid‐solution formation is a powerful technique that enhances and adds properties through elemental mixing, but unfortunately, some elements simply cannot mix as their chemical nature prevents a thermodynamically stable structure. For example, the inherent nobility of platinum group metals does not favor bond formation and precludes their incorporation into higher (boron‐rich) metal borides. However, we demonstrate that when using five or more constituents, the higher mixing entropy will overcome these chemical limitations and form a stable high‐entropy alloy, demonstrating the formation of new compounds with substituents that are seemingly impossible with a traditional metal alloying approach. The high‐entropy boride (HEB) Al0.2Nb0.2Pt0.2Ta0.2Ti0.2B2 was synthesized, where platinum was forced to occupy a 12‐coordinate site, sandwiched between honeycomb borophene sheets. In addition to the unusual coordination, the boron serves as a poison panacea. Pure platinum is strongly susceptible to sulfur poisoning by adsorption, rendering a platinum catalyst ineffective. Boron is known to be resistant to sulfur poisoning. The boron sheets present in the HEB shield the platinum from sulfur while maintaining high catalytic activity. This is confirmed with the facile hydrogenation of thiol‐containing nitro compounds, where the HEB resists sulfur poisoning while retaining its high catalytic activity. [ABSTRACT FROM AUTHOR]

In this work, we described a general monometallic cobalt heterogeneous catalyst for the hydroformylation of olefins, achieving good yields and recyclability up to five times with no loss in catalytic activity. These catalysts were prepared through the pyrolysis of the well‐defined metal–organic framework ZIF‐67. The addition of steam during the pyrolysis did not affect the final phase composition of the cobalt particles; nonetheless, it resulted in an increase of the cobalt particle size and the partial removal of the carbonaceous matrix. The materials were extensively characterized by several techniques, and it was observed that the N‐doped carbon matrix played a crucial role in terms of activity and stability. Different liquid olefins, including internal, terminal, and cyclic were successfully tested in our hydroformylation protocol. Aldehydes yields of 48%–77% for different liquid olefins were achieved with the optimal catalyst. No leaching of the active sites was observed over five catalytic cycles. The high stability of the catalyst is attributed to the presence of stabilizing nitrogen atoms bearing the cobalt sites. [ABSTRACT FROM AUTHOR]

Homogeneous electrocatalysts typified by transition‐metal complex show transcendent potency in efficient energy catalysis through molecular design. For example, metal complexes with elaborate design performed wonderful activity and selectivity for electrocatalytic CO2 reduction. Primary coordination sphere of metal complexes plays a key role in regulating its intrinsic redox properties and catalytic activity. However, the overall reduction efficiency of CO2 is also bound up with the substrate activation process. Transition‐metal complexes are hoped to exhibit reasonable redox potential, reactive activity, and stability, while binding and activating CO2 molecules to achieve efficient CO2 reduction. Construction of second coordination sphere, especially hydrogen‐bonding network of transition‐metal complexes, is reported to be the “kill two birds with one stone” strategy to realize efficient CO2 reduction catalysis via systematic catalyst properties modulation and substrate activation. Herein, we present recent progress on the construction of hydrogen‐bonding network in the second coordination sphere of metal complexes by ligand modification or the introduction of exogenous organic ligand, and the resulted productive enhancement of the catalytic performance of metal complexes by the improvement of adsorption capacity and activation of CO2, proton transfer rate, and stability of reaction intermediates, and so forth. [ABSTRACT FROM AUTHOR]

The present study reports the synthesis, characterization, and application of NiCo bimetallic catalysts to produce 2,5‐furandicarboxylic acid (FDCA) via the oxidation of bio‐renewable 5‐hydroxymethylfurfural (HMF). FDCA is a biopolymer precursor and a potential replacement for terephthalic acid (TPA). The catalysts were synthesized via the co‐precipitation method in different molar ratios of NiCo, followed by calcination in a muffle furnace. As a result, the complete conversion of HMF and a maximum 84.89 % FDCA yield was measured at 50 °C in 50 minutes in the presence of NiCo(3 : 1) catalyst. In addition, effect reaction parameters, including catalyst amount, temperature, time, base, and oxidant amount on the FDCA yield, were studied, and the process was optimized. The NiCo(3 : 1) catalyst showed a negligible loss in activity for at least five cycles. The higher catalytic activity and stability are attributed to the synergistic effect of bimetallic catalysts, such as higher lattice oxygen. Accordingly, the catalyst was characterized using BET, XRD, H2‐TPR, CO2‐TPD, HR‐TEM, and XPS to correlate their properties and activity. The reaction products were analyzed quantitatively using HPLC and qualitatively using HR‐MS. [ABSTRACT FROM AUTHOR]

This study provides a comprehensive review of recent advancements in photocatalytic and electrocatalytic carbon dioxide reduction using titanium dioxide catalysts. The basic concepts of light absorption, electron transport, and reduction processes are introduced in this paper, which also delves into the specifics of photocatalytic and electrocatalytic reduction of carbon dioxide. The paper highlights the key applications and benefits of titanium dioxide, including its strong stability, outstanding light absorption capacity, and good electron transport performance, in the photocatalytic and electrocatalytic reduction of carbon dioxide. Furthermore, it examines the impact of various surface modification techniques on catalytic performance, as well as the effects of various titanium dioxide catalyst forms on catalytic activity and selectivity in carbon dioxide reduction. The in‐depth analysis exhibit promising catalytic properties and hold significant potential for future advancements. However, some obstacles still need to be overcome, such as increasing catalytic activity and selectivity while minimizing energy dissipation. In order to improve catalytic performance and efficiency, future research should prioritize the optimization of structural design and surface modification techniques for catalysts. Additionally, the paper provides a scientific foundation for accomplishing sustainable carbon conversion, it also calls for additional experimental and theoretical research into the mechanism of action for titanium dioxide catalyst. [ABSTRACT FROM AUTHOR]

A set of Cu/ZnO/ZrO2 catalysts doped with Group‐IIIA elements (M=B, Al, Ga & In) were synthesized via a facile single‐step evaporation‐induced self‐assembly (EISA) method to tune up the catalyst basicity and modulate the structure to improve the methanol yield in CO2 hydrogenation reaction. To understand the catalyst's textural properties and catalytic activity, prepared catalysts were exposed to several in‐situ/ex‐situ characterization techniques like Physisorption & Chemisorption studies, XRD, XPS, TEM, and in‐situ DRIFT. The addition of group IIIA elements has a significant impact on the CO2 conversion and Methanol selectivity via tailoring the important textural properties such as metallic surface area of Cu, reducibility of catalysts, particle size, controlled oxygen vacancy, and basicity of catalyst surface. CZZ doped with Al appeared to be the best catalyst, in this study. The modified Cu‐ZnO interface via density functional theory (DFT) calculations also indicated that the CO2 adsorption energy is found to be highest for CZZAl, which is concomitant with CO2‐TPD analysis results. The lowest to highest CO2 adsorption energy order over the catalyst set follows CZZIn

Organocatalysts are used in a wide range of polymerisation reactions with the advantage of being often more benign or sustainable, while maintaining high catalytic activity. However, the low thermal stability of most of these compounds remain an obstacle for high temperature reactions. It was recently reported that complexes formed from a base such as 1,4,7‐triazabicyclodecene (TBD) and an acid such as methane sulfonic acid (MSA) demonstrate high thermal stability while efficiently catalysing polycondensation reactions. However, TBD is not cost‐efficient neither available at industrial scale, which makes it unfit for scaling up. Herein, eight different bases have been investigated to replace TBD. First, we confirmed the complex formation between the MSA and the base by nuclear magnetic resonance spectroscopy while confirming the thermal stability of the mixtures by thermogravimetric analysis before evaluating their catalytic activity in the self‐condensation of 1,6‐hexanediol. Among the different investigated bases, 1,1,3,3‐tetramethyl guanidine (TMG) appeared to be the most appropriate option since it gathers both high thermal stability and good catalytic activity. These characteristics make TMG suitable for replacing TBD in the self‐condensation of diols while opening the way for being used in a wide range of high temperature (de)polymerisation reactions. [ABSTRACT FROM AUTHOR]

5‐Hydroxymethylfurfural (5‐HMF) derived from lignocellulose represents an important platform molecule that could be employed in the selective hydrogenation of the furan ring to prepare 5‑hydroxymethyltetrahydrofurfural (HMTHF). However, the reported catalytic systems for the synthesis of HMTHF using 5‐HMF still require additional hydrogen pressure. In this study, the Pd/ZrO2 catalyst with uniformly dispersed Pd nanoparticles was prepared via a simple impregnation reduction process. This catalyst exhibited excellent catalytic activity and selectivity for the hydrogenation of 5‐HMF to HMTHF. High HMTHF yields up to 92.3% were produced under mild reaction conditions of ambient hydrogen pressure and room temperature in methanol solvent. This result was superior to the most catalytic systems that had been reported so far. The mechanism study revealed that the active hydrogen species on the surface of the Pd nanoparticles and the reaction solvent in this study were the pivotal factors influencing the hydrogenation of furan rings in 5‐HMF. [ABSTRACT FROM AUTHOR]

The present study delves into electrochemical nitrogen reduction reaction (NRR) for ammonia synthesis using borophane‐supported single‐atom catalysts (SACs) through density functional theory (DFT) calculations. In comparison to previously reported borophene, which serves as a potential substrate for SACs in NRR, hydrogenated borophane, especially borophane‐2H(B5H2), not only prevents metal aggregation, resulting in stable atomically dispersed metal centers, but also enhances catalytic activity by modulating the metal's charge state. Among all candidates, atomic tungsten anchored on W1/borophane‐2H(B5H2) displays the most favorable NRR activity and product selectivity. [ABSTRACT FROM AUTHOR]

In order to alleviate the influence of greenhouse effect on global climate change, the effective utilization of CO2 to prepare fine chemicals should be paid more attention to, however, which is greatly blocked by the catalyst with low efficiency. Here, alkali metal (Li, Na, or K) are employed as a modification aid to prepare CuO/ZrO2 catalyst for CO2 hydrogenation to methanol. The effects of alkali metal on physicochemical properties and catalytic activities of CuO/ZrO2 catalyst were studied in detail by the XRD, N2‐physisorption, ICP‐OES, SEM/EDS, H2/N2O/CO2/NH3‐chemisorption, and evaluation test. The results verified that the use of complex combustion method enabled the uniform combination of all components in precursor. High‐temperature calcination (700 °C) further enhanced the strong interaction and synergistic effect between Cu and ZrO2. Most importantly, the introduction of alkali metal effectively altered the structure and catalytic activity of CuO/ZrO2 catalysts. However, the selectivity to methanol increased while the CO2 conversion decreased regardless of different kinds of alkali metal being introduced to the CuO/ZrO2 catalysts. For example, CuO/ZrO2 catalyst modified by K exhibited excellent performance for methanol production that 98.9% selectivity of methanol based on 8.8% conversion of CO2 after 48 h online reaction. [ABSTRACT FROM AUTHOR]

The functionalization of silica supports with isonicotinamide (NIC) facilitated the stabilization of small (3.5 nm), spherical cobalt nanoparticles (CoNPs) used in catalytic hydrogenation. Various silica matrices, including amorphous, mesoporous, and non‐porous ones, were synthesized and post‐grafted with NIC to serve as ligands for stabilizing CoNPs. Comprehensive characterization techniques were employed to fully analyze the prepared materials, which were then utilized in the catalytic hydrogenation of acetophenone, serving as a benchmark reaction to assess the impact of different silica supports on catalysis. The porosity and surface nature of the silica matrices played crucial roles in anchoring the amide ligand, and the presence of the ligand was essential for stabilizing the nanoparticles. Among the catalysts tested, CoNPs@SBA‐15/NIC exhibited the highest catalytic activity and demonstrated excellent performance in the hydrogenation of alkenes, nitriles, ketones, and quinoline under relatively mild conditions. No significant alteration in catalyst morphology or leaching of metal was observed after the reaction. Notably, this catalytic system achieved turnover numbers comparable to those of homogeneous cobalt catalysts. Additionally, one‐pot tandem reductive amination reactions starting from aldehydes and involving both amines and nitrobenzene yielded secondary and tertiary amines in good yields, highlighting the robustness and versatility of the catalyst. [ABSTRACT FROM AUTHOR]

NiMn oxides with different ratios (NixMnyOz) as well as spinel‐type NiMn2O4 oxides were synthesized and utilized in the catalytic oxidation of toluene. The results indicate that NiMn2Ox synthesized by the oxygen‐only roasting method exhibits superior catalytic activity due to the appropriate metal valence distribution. The catalytic activity is strongly related with the crystalline phase structures, NiMn2O4 spinel oxides catalyst shows the best low‐temperature performance with 90 % conversion (T90) at 230 °C. Characterization results reveal that the superb catalytic performance of NiMn2O4 spinel oxide is mainly profit by the larger surface area, more abundant surface fugacious oxygen, stronger toluene adsorption capacity than that of the other NixMnyOz catalysts, which in favor of the speedy conversion of benzoic acid, improving the toluene catalytic performance. This finding provides a novel design strategy of NiMn composite oxides for synthesis of high‐efficiency performance toluene catalysts. [ABSTRACT FROM AUTHOR]

Sulfonium, selenonium, telluronium triflates, as well as chloronium, bromonium, and iodonium triflates have been examined in the model Schiff condensation as chalcogen‐ and halogen bond donating organocatalysts, respectively. The kinetic data indicated that the catalytic effect of the telluronium salt is provided via the decrease of enthalpy of activation of the reaction, whereas the catalytic effect of the iodonium salt – unexpectedly – is caused by the decrease of the value of the entropy of activation. In addition, it was experimentally shown that the catalytic activity of sulfonium and selenonium salts is significantly lower than that of chloronium and bromonium salts, but the latter pair of species is significantly less stable under the reaction conditions than the former pair. [ABSTRACT FROM AUTHOR]

Phosphonic acid (PA) self‐assembled monolayers (SAMs) were deposited onto Pt/Al2O3 catalysts to modify the support to enable control over CO2 adsorption and CO2 hydrogenation activity. Significant differences in catalytic activity toward CO2 hydrogenation (reverse water‐gas shift, RWGS) were observed after coating Al2O3 with PAs, suggesting that the reaction was mediated by CO2 adsorption on the support. Amine‐functionalized PAs were found to outperform their alkyl counterparts in terms of activity, however there was little effect of amine location in the SAM (i. e., spacing between the amine functional group and phosphonate attachment group). One amine‐PA and one alkyl‐PA, aminopropyl phosphonic acid (C3NH2PA) and methyl phosphonic acid (C1PA), respectively, were investigated in more detail. The C3NH2PA‐modified catalyst was found to bind CO2 as a combination of carbamate and bicarbonate. Additionally, at 30 °C, both PAs were found to reduce CO2 adsorption uptake by approximately 50 % compared to unmodified 5 %Pt/Al2O3. CO2 adsorption enthalpy was measured for the catalysts and found to be strongly correlated with hydrogenation activity, with the trend in binding enthalpy and CO2 hydrogen rate trending as uncoated >C3NH2PA>C1PA. PA SAMs were found to have weaker effects on CO binding and CO selectivity, consistent with selective modification of the Al2O3 support by the PAs. [ABSTRACT FROM AUTHOR]

We carried out a mechanistic investigation of the dehydration of fructose catalyzed by a series of proton‐exchanged faujasite zeolites. Using a combination of analytical tools (HPLC, GC, NMR), we could solve and quantify most of the variety of products formed, including (i) cyclic intermediates (ii) transient species (monomeric and dimeric) (iii) byproducts (oligomeric species and humins). The results prove that the reaction goes through a cyclic mechanism, and we could propose a kinetic model matching most of our experimental results and describing the interplay between the different categories of products. By comparing the performances of different catalysts with varying properties, we surprisingly find that increasing the concentration of Brønsted acid sites induces lower catalytic activity. Contrary to general expectations, the mesoporous volume seems to be the most determining parameter for the activity of the catalysts over the set of catalysts evaluated here, which may be explained by the importance of allowing the reactant a significant accessibility to the active sites. [ABSTRACT FROM AUTHOR]

The catalytic relevance of different surface functionalities present on hydrotalcite‐derived Mg−Al mixed metal oxides (MgAlO) are investigated in the context of ethanol upgrade to n‐butanol. The catalyst structure and active sites were altered through changes in the Mg/Al ratio and introduction of additional redox metal oxide functionalities. After performing a series of catalytic activity tests, operando FTIR characterization, TGA measurements and in situ active center titration; qualitative and quantitative relationships between catalyst structure and catalytic performance are obtained. We found the Mg−Al mixed metal oxides system can catalyze the ethanol to n‐butanol process through a Guerbet reaction pathway, though the process is kinetically limited. By introducing redox active metal oxides to the catalyst formulation, such as MoO3 or V2O5, this problem can be partially solved, but at a cost of losing a significant fraction of high‐strength basic centers which are the most catalytically relevant function in the system, as they control enolate formation rates leading to the C−C coupling step required for n‐butanol formation. [ABSTRACT FROM AUTHOR]

Using the bromide anion exchange (BAE) green method to obtain carbon‐supported nanoparticles, Pt(LaOx)/C was successfully prepared under mild conditions. This material, containing LaOx species generated in situ during the synthesis, was efficiently used as an anode to perform glycerol oxidation in alkaline medium in batch mode and at room temperature. In a direct alcohol fuel cell (DAFC), this catalyst was able to boost the glycerol‐to‐glycerate conversion with a 49% selectivity and a 28% power density higher than the same system using a BAE‐synthesized Pt/C anode. The increase in catalytic activity may be due to the interaction of LaOx with the Pt active sites, acting as a bifunctional electrode. Furthermore, when used as an anode in an electrolysis setup, the selectivity of glycerol toward glycerate increased up to 67%. In situ FTIR and HPLC analyses confirmed the formation of the value‐added glycerol oxidation products. [ABSTRACT FROM AUTHOR]

Phosphonic acid (PA) self‐assembled monolayers (SAMs) were deposited onto Pt/Al2O3 catalysts to modify the support to enable control over CO2 adsorption and CO2 hydrogenation activity. Significant differences in catalytic activity toward CO2 hydrogenation (reverse water‐gas shift, RWGS) were observed after coating Al2O3 with PAs, suggesting that the reaction was mediated by CO2 adsorption on the support. Amine‐functionalized PAs were found to outperform their alkyl counterparts in terms of activity, however there was little effect of amine location in the SAM (i. e., spacing between the amine functional group and phosphonate attachment group). One amine‐PA and one alkyl‐PA, aminopropyl phosphonic acid (C3NH2PA) and methyl phosphonic acid (C1PA), respectively, were investigated in more detail. The C3NH2PA‐modified catalyst was found to bind CO2 as a combination of carbamate and bicarbonate. Additionally, at 30 °C, both PAs were found to reduce CO2 adsorption uptake by approximately 50 % compared to unmodified 5 %Pt/Al2O3. CO2 adsorption enthalpy was measured for the catalysts and found to be strongly correlated with hydrogenation activity, with the trend in binding enthalpy and CO2 hydrogen rate trending as uncoated >C3NH2PA>C1PA. PA SAMs were found to have weaker effects on CO binding and CO selectivity, consistent with selective modification of the Al2O3 support by the PAs. [ABSTRACT FROM AUTHOR]

The new diiron(I) complexes [Fe2Cp2(μ‐CO){μ‐k3C,kN‐C(R1)C(R2)C(CN)NMe(R)}], 3 a–o (R=alkyl or 4‐C6H4OMe; R1=alkyl, aryl, ferrocenyl (Fc), thiophenyl, CO2Me or SiMe3; R2=H, Me or CO2Me) were synthesized in moderate to high yields from the thermal decarbonylation of the bis‐carbonyl precursors 2 a–o, and were structurally characterized by IR and NMR spectroscopy, and single crystal X‐ray diffraction in four cases. Electrochemical behavior of one complex was also investigated. Complexes 3 a–o comprise a highly functionalized, multisite amino‐(cyano)allylidene ligand, including metal coordination of a tertiary amine group. Selected complexes displayed negligible to moderate catalytic activity in CO2/propylene oxide coupling, working under ambient conditions. Additionally, they were investigated as catalysts for the conversion of benzaldehyde to the corresponding borate ester 6 a, using pinacolborane (HBpin) as the borylating agent. Most complexes achieved good conversions at room temperature with 1 % catalyst loading, and data highlight the significant influence of the multisite ligand substituents on the catalytic performance. Notably, complex 3 m (featuring R=4‐methoxyphenyl, R1=Fc, R2=H) displayed the highest activity and effectively catalyzed the hydroboration of various aldehydes and ketones. A plausible mechanistic cycle involves metal coordination of the carbonyl substrate, its activation being possibly facilitated by intramolecular interactions. [ABSTRACT FROM AUTHOR]

This work introduces a robust acid‐base catalytic system based on the zirconium‐based metal‐organic framework (Zr‐MOF) MOF‐808, selected for its open structure, high stability, and low presence of structural defects compared to other Zr‐MOFs. Four bifunctional benzoate ligands bearing free carboxylic acid (‐COOH) and nitrogen‐containing groups were introduced into the MOF‐808 using solvent‐assisted ligand exchange methods. Unlike other materials, the acid and base sites in the bifunctional MOF‐808 materials are situated in the same capping ligand, leading to a bifunctional behavior between the two neighboring sites. The system was tested for Knoevenagel condensation and deacetylation‐Knoevenagel tandem reactions, demonstrating high catalytic activity and excellent yields. Additionally, computational modeling provided insights into the catalytic mechanism and the role of the acid‐base sites. The study provides a better understanding of the unique behavior of the bifunctional MOF‐808 catalyst and offers prospects for designing new and efficient catalytic systems for organocatalysis. [ABSTRACT FROM AUTHOR]

Diels‐Alder (DA) cycloaddition of chalcones to anthracene and its 9‐substituted derivatives is an example of a demanding reaction that is not effective even under increased pressure. In this article we show that an easily accessible complex cation [Co(CH3NO2)6]2+ stabilized by weakly coordinating anion [Al(OC(CF3)3)4]− exhibits good catalytic activity in the reaction. Our screening covering chalcone and anthracene derivatives with either activating or deactivating effects on reactivity in DA cycloadditions show that the catalyst allows to obtain [4+2] cycloadducts with yields up to 99 % under mild conditions, even for 9‐bromoanthracene – a very poor diene in DA reactions. The reaction proceeds best in liquid SO2, which is an unusual solvent for this type of reaction. 9‐methylanthracene ‐ the most reactive diene among those tested in the study ‐ gives two regioisomeric cycloadducts and their ratio depends on the solvent used. Modeling of the reaction with DFT methods shows that Co(II) significantly lowers the activation energy of the cycloaddition. In the case of 9‐bromoanthracene the effect is much more pronounced than with e. g. recently reported redox‐activation of the diene, which is in agreement with much better yields obtained with the use of the cobalt catalyst. [ABSTRACT FROM AUTHOR]

Methane dehydroaromatization (MDA) is one of the most promising technologies for directly transforming methane into aromatics. Unlike the extensively investigated Mo/ZSM‐5 catalysts, the structure and, consequently, the catalytic activity of Fe/ZSM‐5 are markedly influenced by the method of preparation, as shown here. In this study, we prepared 2 % and 4 % Fe/ZSM‐5 catalysts via wet impregnation (WI) and incipient wetness impregnation (IWI). Characterizations (XRD, STEM, UV‐Vis, NH3‐TPD and H2‐TPR) reveal that 2 %Fe‐WI mainly possesses isolated or low‐polymerized Fe species within zeolite channels, leading to a rapid activation and a higher benzene yield due to the faster reduction to iron suboxides under MDA conditions. In contrast, 2 %Fe‐IWI contains bulk iron oxide aggregates, resulting in a slower activation as these aggregates transform into iron carbide through successive reduction and carbonization. A deactivation kinetic study applied to the 2 % catalysts further demonstrates the quantitative relation between Fe site isolation and catalytic activity. Although both 4 % catalysts inevitably form sizable iron oxide clusters and particles due to the high Fe/Al ratio, similar trends are noted, with the WI catalysts exhibiting a shorter induction/activation period and a higher yield of benzene, paralleling observations made with 2 % catalysts. [ABSTRACT FROM AUTHOR]

We present a highly efficient single‐atom catalyst (SACs) tailored for nitroarene reduction using NaBH4 under ambient conditions. Employing an unique approach, we harnessed NaCl under high temperature to create host materials enriched with negatively charged nitrogenous and oxygenated functional groups, capable of anchoring and stabilizing Ni ions within the aromatic structure. The nickel single sites were prepared by a straightforward cation exchange method. STEM‐HAADF imaging confirmed the presence of nickel single‐atoms, while XPS, FTIR, and Raman spectra validated nickel coordination within the catalyst. Remarkably, the CN−Ni catalyst exhibited exceptional catalytic performance under ambient conditions, achieving a high catalytic activity with NaBH4 (TOF 2246± ${\pm }$ 452 h−1 and 107± ${\pm }$ 47 mmol g−1 min−1). It also demonstrated remarkable conversion exceeding 90 % and outstanding selectivity. Equally impressive was its ability to maintain full catalytic activity over multiple reaction cycles, highlighting its robustness. This work is a significant leap in SACs design, offering a versatile and highly effective preparation method for SACs based on N‐doped carbon with far‐reaching implications in industrial reduction reactions. [ABSTRACT FROM AUTHOR]

Mononuclear and multinuclear O^N^O‐donor Zn(II) complexes are herein reported as catalysts in the ring‐opening polymerization (ROP) of rac‐lactide (rac‐LA) and depolymerization of poly(lactide) (PLA). Reactions of imino‐phenol proligand 2[((2‐hydroxyethyl)imino)methyl]phenol (L1H2) with ZnCl2 and ZnEt2 afforded the dinuclear and tetranuclear complexes [Zn2(L1H)2Cl2] (Zn1) and [Zn4(L1)4] (Zn2), respectively. Separately, treatments of proligands 2‐[1‐((2‐hydroxyethyl)imino)ethyl]phenol (L2H2) and [((2‐methoxyethyl)imino)methyl]phenol (L3H) with ZnCl2 gave the respective mononuclear complexes [Zn(L2H2)2Cl2] (Zn3) and [Zn(L3H)2Cl2] (Zn4), while the reactions of L3H with ZnEt2 afforded the bis(chelated) mononuclear complex [Zn(L3)2] (Zn5). The complexes were characterized using NMR and IR spectroscopy, elemental analyses and single crystal X‐ray crystallography. All the Zn(II) complexes showed high catalytic activities in the ROP of rac‐LA (kapp of up to 4.18 × 10−4 s−1) to give moderate molecular weight PLA (39,960 g mol−1) with relatively narrow dispersities (Đ = 1.4–2.1). The complexes produced mainly atactic PLAs with Pr values of 0.51–0.58. More significantly, complexes Zn1, Zn2, and Zn5 were also active in the depolymerization of commercial PLA in methanol (kapp of up to 2.67 × 10−4 s−1) to produce alkyl lactates. The ROP and depolymerization behavior were largely controlled by the structure and nuclearity of the complexes. [ABSTRACT FROM AUTHOR]

Biomolecular condensates are membraneless organelles that orchestrate various metabolic pathways in living cells. Understanding how these crowded structures regulate enzyme reactions remains yet challenging due to their dynamic and intricate nature. Coacervate microdroplets formed by associative liquid‐liquid phase separation of oppositely charged polyions have emerged as relevant condensate models to study enzyme catalysis. Enzyme reactions within these droplets show altered kinetics, influenced by factors such as enzyme and substrate partitioning, crowding, and interactions with coacervate components; it is often challenging to disentangle the contributions of each. Here, we investigate the peroxidase activity of a de novo enzyme within polysaccharide‐based coacervates. By comparing the reaction kinetics in buffer, in a suspension of coacervates and in the bulk coacervate phase collected after centrifugation of the droplets, we show that the coacervate phase significantly increases the enzyme catalytic efficiency. We demonstrate that the main origin of this enhanced activity lies in macromolecular crowding coupled to changes in the conformational dynamics of the enzyme within the coacervate environment. Altogether, these findings underline the crucial role of the coacervate matrix in enzyme catalysis, beyond simple partitioning effects. The observed boost in enzyme activity within the coacervate phase provides insights for designing biocatalytically active synthetic organelles. [ABSTRACT FROM AUTHOR]

A series of bimetallic‐ionic liquid (IL) pincer catalysts Pd−M@IL were synthesized using low Pd‐loading amount (0.3 %) and adopting six kinds of ion liquids with the cation containing the imidazole ring, and then evaluated the catalytic activities toward 2‐ethylanthraquinone hydrogenation reaction with the purpose to produce H2O2. Under the reaction conditions of 60 °C, 0.30 MPa and 15 min reaction time, over the catalysts Pd−La@[BMIm]Ac/alu and Pd−La@[VBIM]Br/alu achieved high hydrogenation efficiency(9.4 g/L and 8.5 g/L) but also high selectivity toward the active anthraquinone (98.9 % and 99.6 %). Through characterizations of STEM, TPD, in‐situ XPS, etc., it illustrates that the pincer catalysts Pd−La@[BMIm]Ac/alu and Pd−La@[VBIM]Br/alu have much better dispersity than the bimetallic Pd−La/alu, these two ionic liquids of [BMIm]Ac and [VBIM]Br provide different local environment around Pd−La sites, which in turn modulate the catalytic activity of the pincer‐catalysts toward anthraquinone hydrogenation. DFT calculations disclose the unique electron transfer between ILs ([BMIm]Ac and [VBIM]Br) and Pd−La clusters and subsequent changes of energy barriers for anthraquinone hydrogenation. The work illuminates a facile strategy to design novel hydrogenation catalysts through combining the pincer microenvironment partially encapsulated by the cation and the anion of ionic liquids with the internal bimetallic sites. [ABSTRACT FROM AUTHOR]

In this study, we assess the suitability of Pd alloys in direct mechanocatalytic coupling reactions. Copper (Cu) and nickel (Ni) were alloyed with palladium (Pd), alongside testing a high entropy alloy and palladium gold alloy. Compared to pure Pd balls the alloys are promising in terms of mechanical properties and costs. Combining Pd with Cu and Ni improved mechanical resilience by up to 330 % while retaining catalytic activity, for the tested Suzuki‐Miyaura and Sonogashira‐Hagihara couplings. Both of which led to good to excellent yields within one hour. Notably, alloys containing 20 % Pd showed increased yields of over 80 % in the Sonogashira coupling, comparable to pure Pd. XPS and in‐situ PXRD analysis showcased the influence of alloyed metals on catalytic processes, emphasizing the significance of the surface composition of milling balls. [ABSTRACT FROM AUTHOR]

A mechanochemical‐enabled Ru‐catalyzed regioselective synthesis of 3,4‐isoxazoles and 3,4,5‐isoxazoles from terminal and internal alkynes and hydroxyimidoyl chlorides is reported. This solid‐state and solvent‐free approach carefully examines the impact of the milling conditions on regiocontrol in 1,3‐dipolar cycloadditions using mechanochemical means. The study reveals that milling frequency, jar material, and the choice of liquid additive for liquid‐assisted grinding (LAG) significantly influence the catalytic activity of the Ru catalyst. Transmission electron microscope (TEM) analysis confirms the crucial role of coordinating liquid additives such as acetone and cyclopentyl methyl ether (CPME) in stabilizing and reducing the size of the in‐situ formed Ru nanoparticles, which is essential for catalytic activity. The applicability of this protocol is further demonstrated through the synthesis of a library of 3,4‐ and 3,4,5‐isoxazoles from a wide range of terminal and internal alkynes with varying physical states and electronic properties that highlights the potential of this method for the synthesis of more complex target molecules. [ABSTRACT FROM AUTHOR]

Mixed‐potential‐driven catalysis, in which anodic and cathodic reactions are electrochemically short‐circuited, converts the Gibbs free energy difference into overpotentials that drive both half‐reactions without an external energy input. We developed a theoretical framework that suggests that the catalytic activities of individual catalyst components determine the distribution of the aforementioned driving forces. By short‐circuiting spatially separated electrodes made of Au/C with reduced‐graphene oxide, nitrogen‐doped reduced‐graphene oxide, caged nitrogen‐doped reduced‐graphene oxide, Pt/C, or Pd/C, we demonstrated this framework using glucose oxidation as a model, given its significance in generating high‐value products and its potential in fuel cell technology. A short‐circuit current was detected in the absence of external potentials, demonstrating electron transfer during glucose oxidation. Additionally, by correlating the mixed potential predicted from the polarization curves of each half‐reaction with the mixed potential measured in short‐circuit experiments under the same conditions, we confirmed that the kinetic activity of each catalyst component determines the mixed potential. This, in turn, affects the division of the driving force. Driving force partitioning is a potent tool for enhancing the overall rate of a reaction. Our findings may facilitate the design of not only glucose oxidation catalysts but also other heterogeneous catalysts based on mixed‐potential‐driven reaction mechanisms. [ABSTRACT FROM AUTHOR]

It was crucial to develop a catalyst with high catalytic activity at low temperatures, as the zinc‐based catalysts were prone to deactivation in the high‐temperature reaction of acetylene acetoxylation, and Ionic liquid (IL)‐silver (Ag) catalysts were synthesized and applied in acetylene acetoxylation. The X‐ray diffraction, transmission electron microscopy, and X‐ray photoelectron spectroscopy characterizations displayed that Ag species were stabilized in the state of Ag+, and the dispersion of the Ag active species was effectively improved in supported‐ionic‐liquid‐phase (SILP) system. Furthermore, we prepared Ag‐IL liquid phase catalysts for catalyzing acetylene acetoxylation in liquid phase systems. It was demonstrated that the presence of ILs could effectively stabilize the Ag+ active site. The catalytic performance of the Ag‐IL/AC catalyst prepared in this article at a low temperature of 180 °C was 2.5 times that of the traditional Zn/AC catalyst. The development of low‐temperature catalysts would play a driving role in the development of acetylene acetoxylation. [ABSTRACT FROM AUTHOR]

Designing low‐cost and stable electrocatalysts with enhanced activity and selectivity for CO2 valorization to useful chemicals and fuels faces enormous challenges to address the pressing climate change concerns. Synergistic interactions between the atoms in double atom catalysts has emerged as a promising tool to tune and boost CO2 activation and reduction. In this work, we systematically designed highly stable transition‐metal‐free homo‐ and hetero‐biatomic catalysts based on Al, Be, B and Si supported on TCNQ monolayer for CO2 reduction to C1 products using dispersion corrected periodic density functional theory calculations. Our findings reveal that transition‐metal‐free homo‐and hetero‐biatomic TCNQ catalysts can effectively capture and activate the CO2 molecule with binding energies ranging from 0.09 to 2.35 eV. Extensive free energy calculations to screen the favourable reaction pathways to different C1 products (CO, HCOOH, CH3OH and CH4) demonstrate that Al2‐TCNQ, AlBe‐TCNQ and BeSi‐TCNQ stand out as potential candidates for catalyzing CO2RR to methanol in a selective manner, suppressing the competitive HER simultaneously. Remarkably, BeSi‐TCNQ shows the best catalytic activity towards CO2 reduction to methanol at record low limiting potential of −0.29 V with spontaneous desorption of the final product. From the in‐depth examination of the electronic structure details, integrated projected density of states and crystal orbital Hamilton populations are used to understand and rationalize the binding interactions between the adsorbed CO2 molecule and the homo‐ or hetero‐biatomic TCNQ catalysts. Moreover, the ΔG*COOH‐ΔG*CO2 and ΔG*HCOOH‐ΔG* OCHO/*COOH values are found to provide reasonable guidance to evaluate the overall CO2RR performance of homo‐ and hetero‐biatomic TCNQ catalysts, respectively. Therefore, our findings provide significant insights for designing transition metal‐free homo‐ and hetero‐biatomic catalysts with intriguing properties for improving CO2 utilization and conversion. [ABSTRACT FROM AUTHOR]

The development of high active and stable Pt−M (M=transition metals) electrocatalysts for oxygen reduction reaction (ORR) is crucial for the commercialization of proton exchange membrane fuel cells (PEMFCs). The main challenge of Pt−M electrocatalysts is their instability, mainly due to the leaching of M. In this study, we report the design of P and O co‐doped octahedral PtCo alloy on Ketjen carbon black (Px‐Oct PtCo/C) through a seed‐mediated synthesis. In‐situ FTIR spectroscopy revealed that P0.61‐Oct PtCo/C has the lowest d‐band center, thereby enhancing the catalytic activity. The strong interaction formed by chemical bond between O and Co in Px‐Oct PtCo/C, observed by EXAFS spectra effectively inhibited the dissolution of Co and improved the ORR stability. The mass activity and specific activity of P0.61‐Oct PtCo/C can reach 0.61 A mgPt−1 and 2.4 mA cm−2, respectively, which is 4.1 times and 10.9 times higher than that of commercial Pt/C. After 50,000 potential cycles, the loss of mass activity is only 25 %, surpassing the DOE 2025 target of less than 40 % loss after 30,000 cycles. This study offers an alternative approach to enhancing the activity and durability of Pt−M electrocatalysts for the ORR. [ABSTRACT FROM AUTHOR]