Against the backdrop of escalating global climate change and energy crises,the resource utilization of carbon dioxide(CO_(2)),a major greenhouse gas,has become a crucial pathway for achieving carbon peaking and carbon...Against the backdrop of escalating global climate change and energy crises,the resource utilization of carbon dioxide(CO_(2)),a major greenhouse gas,has become a crucial pathway for achieving carbon peaking and carbon neutrality goals.The hydrogenation of CO_(2)to methanol not only enables carbon sequestration and recycling,but also provides a route to produce high value-added fuels and basic chemical feedstocks,holding significant environmental and economic potential.However,this conversion process is thermodynamically and kinetically limited,and traditional catalyst systems(e.g.,Cu/ZnO/Al_(2)O_(3))exhibit inadequate activity,selectivity,and stability under mild conditions.Therefore,the development of novel high-performance catalysts with precisely tunable structures and functionalities is imperative.Metal-organic frameworks(MOFs),as crystalline porous materials with high surface area,tunable pore structures,and diverse metal-ligand compositions,have the great potential in CO_(2)hydrogenation catalysis.Their structural design flexibility allows for the construction of well-dispersed active sites,tailored electronic environments,and enhanced metal-support interactions.This review systematically summarizes the recent advances in MOF-based and MOF-derived catalysts for CO_(2)hydrogenation to methanol,focusing on four design strategies:(1)spatial confinement and in situ construction,(2)defect engineering and ion-exchange,(3)bimetallic synergy and hybrid structure design,and(4)MOF-derived nanomaterial synthesis.These approaches significantly improve CO_(2)conversion and methanol selectivity by optimizing metal dispersion,interfacial structures,and reaction pathways.The reaction mechanism is further explored by focusing on the three main reaction pathways:the formate pathway(HCOO*),the RWGS(Reverse Water Gas Shift reaction)+CO*hydrogenation pathway,and the trans-COOH pathway.In situ spectroscopic studies and density functional theory(DFT)calculations elucidate the formation and transformation of key intermediates,as well as the roles of active sites,metal-support interfaces,oxygen vacancies,and promoters.Additionally,representative catalytic performance data for MOFbased systems are compiled and compared,demonstrating their advantages over traditional catalysts in terms of CO_(2)conversion,methanol selectivity,and space-time yield.Future perspectives for MOF-based CO_(2)hydrogenation catalysts will prioritize two main directions:structural design and mechanistic understanding.The precise construction of active sites through multi-metallic synergy,defect engineering,and interfacial electronic modulation should be made to enhance catalyst selectivity and stability.In addition,advanced in situ characterization techniques combined with theoretical modeling are essential to unravel the detailed reaction mechanisms and intermediate behaviors,thereby guiding rational catalyst design.Moreover,to enable industrial application,challenges related to thermal/hydrothermal stability,catalyst recyclability,and cost-effective large-scale synthesis must be addressed.The development of green,scalable preparation methods and the integration of MOF catalysts into practical reaction systems(e.g.,flow reactors)will be crucial for bridging the gap between laboratory research and commercial deployment.Ultimately,multi-scale structure-performance optimization and catalytic system integration will be vital for accelerating the industrialization of MOF-based CO_(2)-to-methanol technologies.展开更多
To elucidate the effect of calcite-regulated activated carbon(AC)structure on low-temperature denitrification performance of SCR catalysts,this work prepared a series of Mn-Ce/De-AC-xCaCO_(3)(x is the calcite content ...To elucidate the effect of calcite-regulated activated carbon(AC)structure on low-temperature denitrification performance of SCR catalysts,this work prepared a series of Mn-Ce/De-AC-xCaCO_(3)(x is the calcite content in coal)catalysts were prepared by the incipient wetness impregnation method,followed by acid washing to remove calcium-containing minerals.Comprehensive characterization and low-temperature denitrification tests revealed that calcite-induced structural modulation of coal-derived AC significantly enhances catalytic activity.Specifically,NO conversion increased from 88.3%of Mn-Ce/De-AC to 91.7%of Mn-Ce/De-AC-1CaCO_(3)(210℃).The improved SCR denitrification activity results from the enhancement of physicochemical properties including higher Mn^(4+)content and Ce^(4+)/Ce^(3+)ratio,an abundance of chemisorbed oxygen and acidic sites,which could strengthen the SCR reaction pathways(richer NH_(3)activated species and bidentate nitrate active species).Therefore,NO removal is enhanced.展开更多
Using photoelectrocatalytic CO_(2) reduction reaction(CO_(2)RR)to produce valuable fuels is a fascinating way to alleviate environmental issues and energy crises.Bismuth-based(Bi-based)catalysts have attracted widespr...Using photoelectrocatalytic CO_(2) reduction reaction(CO_(2)RR)to produce valuable fuels is a fascinating way to alleviate environmental issues and energy crises.Bismuth-based(Bi-based)catalysts have attracted widespread attention for CO_(2)RR due to their high catalytic activity,selectivity,excellent stability,and low cost.However,they still need to be further improved to meet the needs of industrial applications.This review article comprehensively summarizes the recent advances in regulation strategies of Bi-based catalysts and can be divided into six categories:(1)defect engineering,(2)atomic doping engineering,(3)organic framework engineering,(4)inorganic heterojunction engineering,(5)crystal face engineering,and(6)alloying and polarization engineering.Meanwhile,the corresponding catalytic mechanisms of each regulation strategy will also be discussed in detail,aiming to enable researchers to understand the structure-property relationship of the improved Bibased catalysts fundamentally.Finally,the challenges and future opportunities of the Bi-based catalysts in the photoelectrocatalytic CO_(2)RR application field will also be featured from the perspectives of the(1)combination or synergy of multiple regulatory strategies,(2)revealing formation mechanism and realizing controllable synthesis,and(3)in situ multiscale investigation of activation pathways and uncovering the catalytic mechanisms.On the one hand,through the comparative analysis and mechanism explanation of the six major regulatory strategies,a multidimensional knowledge framework of the structure-activity relationship of Bi-based catalysts can be constructed for researchers,which not only deepens the atomic-level understanding of catalytic active sites,charge transport paths,and the adsorption behavior of intermediate products,but also provides theoretical guiding principles for the controllable design of new catalysts;on the other hand,the promising collaborative regulation strategies,controllable synthetic paths,and the in situ multiscale characterization techniques presented in this work provides a paradigm reference for shortening the research and development cycle of high-performance catalysts,conducive to facilitating the transition of photoelectrocatalytic CO_(2)RR technology from the laboratory routes to industrial application.展开更多
Supported metal catalysts are the backbone of heterogeneous catalysis,playing a crucial role in the modern chemical industry.Metal-support interactions(MSIs)are known important in determining the catalytic performance...Supported metal catalysts are the backbone of heterogeneous catalysis,playing a crucial role in the modern chemical industry.Metal-support interactions(MSIs)are known important in determining the catalytic performance of supported metal catalysts.This is particularly true for single-atom catalysts(SACs)and pseudo-single-atom catalysts(pseudo-SACs),where all metal atoms are dispersed on,and interact directly with the support.Consequently,the MSI of SACs and pseudo-SACs are theoretically more sensitive to modulation compared to that of traditional nanoparticle catalysts.In this work,we experimentally demonstrated this hypothesis by an observed size-dependent MSI modulation.We fabricated CoFe_(2)O_(4) supported Pt pseudo-SACs and nanoparticle catalysts,followed by a straightforward water treatment process.It was found that the covalent strong metal-support interaction(CMSI)in pseudo-SACs can be weakened,leading to a significant activity improvement in methane combustion reaction.This finding aligns with our recent observation of CoFe_(2)O_(4) supported Pt SACs.By contrast,the MSI in Pt nanoparticle catalyst was barely affected by the water treatment,giving rise to almost unchanged catalytic performance.This work highlights the critical role of metal size in determining the MSI modulation,offering a novel strategy for tuning the catalytic performance of SACs and pseudo-SACs by fine-tuning their MSIs.展开更多
The possibility and feasibility of using supercritical fluid СО<sub>2</sub> extraction process have been investigated and described in the book as part of the task of spent catalysts regeneration. The an...The possibility and feasibility of using supercritical fluid СО<sub>2</sub> extraction process have been investigated and described in the book as part of the task of spent catalysts regeneration. The analysis of deactivating compounds has been carried out for industrial catalysts such as: 1) palladium catalyst G-58E of ethane-ethylene fraction hydrogenation;2) nickel/kieselguhr catalyst of process of separating acetylenic compounds from isoprene;3) active aluminum oxide catalyst of methyl phenyl carbinol dehydration process;4) palladium catalyst LD-265 of hydrocarbons hydrogenation process;5) nickel-molybdenum catalysts DN-3531 and Criterion 514 of kerosene hydrotreating process. The results of the study of catalyst deactivating compounds solubility in pure supercritical carbon dioxide and supercritical carbon dioxide are modified with polar additive. The results of the solubility study are described using the Peng-Robinson equation of state. The results of the implementation of the supercritical fluid СО<sub>2</sub> extraction process with respect to deactivated industrial catalyst samples have been provided. A comparison of the characteristics of samples of catalysts regenerated using the traditional approach and the SC-CO<sub>2</sub> extraction process has been conducted. The possibility of using supercritical fluid CO<sub>2</sub> impregnation process in the synthesis of a palladium catalyst has been investigated. The synthesis of palladium chloride-based organometallic complexes has been carried out. The results of the study of solubility thereof in supercritical carbon dioxide have been provided. A dynamic supercritical fluid CO<sub>2</sub> impregnation process condition has been implemented. A comparison of the characteristics of palladium catalyst samples synthesized using the conventional approach and SC-CO<sub>2</sub> impregnation process has been conducted and presented in the book.展开更多
Exploiting non-precious metal catalysts with excellent oxygen reduction reaction(ORR)performance for energy devices is paramount essential for the green and sustainable society development.Herein,low-cost,high-perform...Exploiting non-precious metal catalysts with excellent oxygen reduction reaction(ORR)performance for energy devices is paramount essential for the green and sustainable society development.Herein,low-cost,high-performance biomass-derived ORR catalysts with an asymmetric Fe-N_(3)P configuration was prepared by a simple pyrolysis-etching technique,where carboxymethyl cellulose(CMC)was used as the carbon source,urea and 1,10-phenanthroline iron complex(FePhen)as additives,and Na_(3)PO_(4)as the phosphorus dopant and a pore-forming agent.The CMC-derived FeNPC catalyst displayed a large specific area(BET:1235 m^(2)g^(-1))with atomically dispersed Fe-N_(3)P active sites,which exhibited superior ORR activity and stability in alkaline solution(E_(1/2)=0.90 V vs.RHE)and Zn-air batteries(P_(max)=149 mW cm^(-2))to commercial Pt/C catalyst(E_(1/2)=0.87 V,P_(max)=118 mW cm^(-2))under similar experimental conditions.This work provides a feasible and costeffective route toward highly efficient ORR catalysts and their application to Zn-air batteries for energy conversion.展开更多
The pursuit of alternative fuel generation technologies has gained momentum due to the diminishing reserves of fossil fuels and global warming from increased CO_(2)emission.Among the proposed methods,the hydrogenation...The pursuit of alternative fuel generation technologies has gained momentum due to the diminishing reserves of fossil fuels and global warming from increased CO_(2)emission.Among the proposed methods,the hydrogenation of CO_(2)to produce marketable carbon-based products like methanol and ethanol is a practical approach that offers great potential to reduce CO_(2)emissions.Although significant volumes of methanol are currently produced from CO_(2),developing highly efficient and stable catalysts is crucial for further enhancing conversion and selectivity,thereby reducing process costs.An in-depth examination of the differences and similarities in the reaction pathways for methanol and ethanol production highlights the key factors that drive C-C coupling.Identifying these factors guides us toward developing more effective catalysts for ethanol synthesis.In this paper,we explore how different catalysts,through the production of various intermediates,can initiate the synthesis of methanol or ethanol.The catalytic mechanisms proposed by spectroscopic techniques and theoretical calculations,including operando X-ray methods,FTIR analysis,and DFT calculations,are summarized and presented.The following discussion explores the structural properties and composition of catalysts that influence C-C coupling and optimize the conversion rate of CO_(2)into ethanol.Lastly,the review examines recent catalysts employed for selective methanol and ethanol production,focusing on single-atom catalysts.展开更多
The metal oxide promoter decisively influences the overall performance of Fe catalysts in the direct hydrogenation of CO_(2)to C_(5+)hydrocarbons.However,the roles of metal oxide promoter for Fe catalysts,particularly...The metal oxide promoter decisively influences the overall performance of Fe catalysts in the direct hydrogenation of CO_(2)to C_(5+)hydrocarbons.However,the roles of metal oxide promoter for Fe catalysts,particularly ZrO_(2),have rarely been investigated.To plug this knowledge gap,a new Fe catalyst promoted with Na and partially reduced ZrO_(x)(Na-FeZrO_(x-9))was developed in this study;the catalyst helped produce C_(5+)hydrocarbons in remarkably high yield(26.3%at 360℃).In contrast to ZrO_(x)-free Fe-oxide,NaFeZrO_(x)-9 exhibited long-term stability for CO_(2)hydrogenation(750 h on-stream).The findings revealed multiple roles of ZrO_(x).Notably,ZrO_(x)decorated the Fe-oxide particles after calcination,thereby suppressing excess particle aggregation during the reaction,and acted as a"coke remover"to eliminate the carbon deposited on the catalyst surface.Additionally,oxygen vacancy(O_(v))sites in ZrO_(x)and electron transfer from ZrO_(x)to Fe sites facilitated the adsorption of CO_(2)at the Zr-Fe interface.展开更多
Catalyst–support interaction plays a crucial role in improving the catalytic activity of oxygen evolution reaction(OER).Here we modulate the catalyst–support interaction in polyaniline-supported Ni_(3)Fe oxide(Ni_(3...Catalyst–support interaction plays a crucial role in improving the catalytic activity of oxygen evolution reaction(OER).Here we modulate the catalyst–support interaction in polyaniline-supported Ni_(3)Fe oxide(Ni_(3)Fe oxide/PANI)with a robust hetero-interface,which significantly improves oxygen evolution activities with an overpotential of 270 mV at 10 mA cm^(-2)and specific activity of 2.08 mA cm_(ECSA)^(-2)at overpotential of 300 mV,3.84-fold that of Ni_(3)Fe oxide.It is revealed that the catalyst–support interaction between Ni_(3)Fe oxide and PANI support enhances the Ni–O covalency via the interfacial Ni–N bond,thus promoting the charge and mass transfer on Ni_(3)Fe oxide.Considering the excellent activity and stability,rechargeable Zn-air batteries with optimum Ni_(3)Fe oxide/PANI are assembled,delivering a low charge voltage of 1.95 V to cycle for 400 h at 10 mA cm^(-2).The regulation of the effect of catalyst–support interaction on catalytic activity provides new possibilities for the future design of highly efficient OER catalysts.展开更多
Xylitol,one of the top twelve chemical building blocks,is commercially synthesized through the xylose hy-drogenation reaction using a metal catalyst.Biochar has emerged as an eco-efficient catalyst support material.In...Xylitol,one of the top twelve chemical building blocks,is commercially synthesized through the xylose hy-drogenation reaction using a metal catalyst.Biochar has emerged as an eco-efficient catalyst support material.In this study,biochar derived from corn stover(BCS)was first used as a metal catalyst support material for xylose hydrogenation into xylitol.The catalyst was prepared by carbonizing corn stover(CS),impregnating the resulting biochar with metal,and reducing the metal-impregnated BCS.The catalyst characteristics were comprehensively explored.The Ru/BCS catalyst was employed in xylose conversion to xylitol at different process temperatures(100-160℃),retention times(3-12 h),H_(2)pressures(2-5 MPa),and Ru contents(1-5%).The highest xylitol yield(87.0 wt.%)and selectivity(91.6%)were derived at 120℃ for 6 h under 4 MPa H_(2)using 5%Ru.Interestingly,the Ru/BCS catalyst showed high stability under the promising process condition.Additionally,xylitol production from hydrolysates enriched with CS xylose was subsequently explored.On the other hand,the catalyst characterization results revealed that the superior catalytic efficiency of 5Ru/BCS was mainly due to the metal nanoparticles embedded in the biochar.Additionally,BCS proved to be an outstanding support material for a bimetallic hydrogenation catalyst(Ru-Ni/BCS).Therefore,these results indicate that BCS can be a competitive support material for metal hydrogenation catalysts,enhancing environmental friendliness and potentially being employed in industrial-scale xylitol production.展开更多
Electrochemical CO_(2) reduction is a sustainable method for producing fuels and chemicals using renewable energy sources.Sn is a widely employed catalyst for formate production,with its performance closely influenced...Electrochemical CO_(2) reduction is a sustainable method for producing fuels and chemicals using renewable energy sources.Sn is a widely employed catalyst for formate production,with its performance closely influenced by the catalyst ink formulations and reac-tion conditions.The present study explores the influence of catalyst loading,current density,and binder choice on Sn-based CO_(2) reduc-tion systems.Decreasing catalyst loading from 10 to 1.685 mg·cm^(-2) and increasing current density in highly concentrated bicarbonate solutions significantly enhances formate selectivity,achieving 88%faradaic efficiency(FE)at a current density of−30 mA·cm^(-2) with a cathodic potential of−1.22 V vs.reversible hydrogen electrode(RHE)and a catalyst loading of 1.685 mg·cm^(-2).This low-loading strategy not only reduces catalyst costs but also enhances surface utilization and suppresses the hydrogen evolution reaction.Nafion enhances formate production when applied as a surface coating rather than pre-mixed in the ink,as evidenced by improved faradaic efficiency and lower cathodic potentials.However,this performance still does not match that of binder-free systems because Sn-based catalysts intrinsic-ally exhibit high catalytic activity,making the binder contribution less significant.Although modifying the electrode surface with binders leads to blocked active sites and increased resistance,polyvinylidene fluoride(PVDF)remains promising because of its stability,strength,and conductivity,achieving up to 72%FE to formate at−30 mA·cm^(-2) and−1.66 V vs.RHE.The findings of this research reveal method-ologies for optimizing the catalyst ink formulations and binder utilization to enhance the conversion of CO_(2) to formate,thereby offering crucial insights for the development of a cost-efficient catalyst for high-current-density operations.展开更多
Carbon-supported mercury catalysts are extensivelyemployed in calcium carbide-based polyvinyl chloride(PVC)industries,but the usage of mercury-based catalysts can pose an environmental threat due to the release of mer...Carbon-supported mercury catalysts are extensivelyemployed in calcium carbide-based polyvinyl chloride(PVC)industries,but the usage of mercury-based catalysts can pose an environmental threat due to the release of mercury into the surrounding area during the operation period.In this study,a highly active and stable mercury-based catalyst was developed,utilizing the nitrogen atom of the support as the anchor site to enhance the interaction between active sites(HgCl_(2))and the carbon support(N-AC).Thermal loss rate testing and thermogravimetric analysis results demonstrate that,compared to commercial activated carbon,N-doped carbon can effectively increase the heat stability of HgCl_(2).The obtained mercury-based catalysts(HgCl_(2)/N-AC)exhibit significant catalytic performance,achieving 2.5 times the C2H2 conversion of conventional HgCl_(2)/AC catalysts.Experimental analysis combined with theoretical calculations reveals that,contrary to the Eley-Rideal(ER)mechanism of HgCl_(2)/AC,the HgCl_(2)/N-AC catalyst follows the Langmuir-Hinshelwood(LH)adsorption mechanism.The nitrogen sites and HgCl_(2) on the catalyst enhance the adsorption capabilities of the HCl and C2H2,thereby improving the catalytic performance.Based on the modification of the active center by these solid ligands,the loading amount of HgCl_(2) on the catalyst can be further reduced from the current 6.5%to 3%.Considering the absence of successful industrial applications for mercury-free catalysts,and based on the current annual consumption of commercial mercury chloride catalysts in the PVC industry,the widespread adoption of this technology could annually reduce the usage of chlorine mercury by 500 tons,making a notable contribution to mercury compliance,reduction,and emissions control in China.It also serves as a bridge between mercury-free and low-mercury catalysts.Moreover,this solid ligand technology can assist in the application research of mercury-free catalysts.展开更多
Electrocatalytic C–N coupling technology offers a promising route for green and sustainable urea synthesis.However,this route faces challenges of low urea yield and Faradaic efficiency due to the high dissociation en...Electrocatalytic C–N coupling technology offers a promising route for green and sustainable urea synthesis.However,this route faces challenges of low urea yield and Faradaic efficiency due to the high dissociation energy of atomic bonds in reactants,complex reaction intermediates,high reaction energy barriers,and competing side reactions.As C–N coupling involves the synergistic action of two or more active sites,it is crucial to develop efficient multi-active-site catalysts to address these challenges.This review analyzes the reaction mechanisms of electrocatalytic C–N coupling for urea synthesis and summarizes effective strategies to achieve multi-active-site catalysts,including heteroatom doping,defect engineering,heterojunctions,and diatomic catalysts.Furthermore,based on this analysis,we propose the universal design principles for high-efficiency multi-activesite catalysts.展开更多
Single-atom catalysts(SACs),in which isolated metal atoms such as palladium(Pd)are anchored on solid supports,promise breakthroughs in energy conversion and catalysis.However,balancing their activity(reaction speed)an...Single-atom catalysts(SACs),in which isolated metal atoms such as palladium(Pd)are anchored on solid supports,promise breakthroughs in energy conversion and catalysis.However,balancing their activity(reaction speed)and stability(longevity)remains challenging,as the interplay between metal atoms,supports,and reactants is poorly understood.展开更多
The development of formic acid dehydrogenation materials with high activity and low cost is key to realizing hydrogen energy utilization.Herein,we describe a specific low-loading strategy to construct a high-activity ...The development of formic acid dehydrogenation materials with high activity and low cost is key to realizing hydrogen energy utilization.Herein,we describe a specific low-loading strategy to construct a high-activity Co atom site catalyst for this reaction.Under optimal conditions,the formic acid dehydrogenation performance of Co─Fe dual-atom catalyst(turnover frequency of 2,446.8 h^(−1),hydrogen production rate of 1,015,306.1 mL gCo^(−1)h^(−1))was 300 times greater than that of commercial 5%Pd/C.High-angle annular dark-field scanning transmission electron microscopy and X-ray absorption fine structure spectra,combined with theoretical calculations,confirm that the presence of different active sites(Co single-atom,Co-Co dual-atom,Co─Fe dual-atom)in catalysts is the key factor affecting their catalytic activity.These findings provide a strong scientific basis for the development of single-atom and dual-atom catalysts.展开更多
Carbon dioxide(CO_(2))can be efficiently converted and utilized through the CO_(2) methanation reaction,which has significant potential benefits for the environment and the economy.The contradiction between the thermo...Carbon dioxide(CO_(2))can be efficiently converted and utilized through the CO_(2) methanation reaction,which has significant potential benefits for the environment and the economy.The contradiction between the thermodynamics and kinetics of the CO_(2) methanation reaction process leads to low CO_(2) conversion at 200-350℃and low methane selectivity at 350-500℃.The utilization of catalysts can solve the contradiction between kinetics and thermodynamics,achieving high CO_(2) methanation efficiency at low temperatures.However,the poor thermal conductivity of powder catalysts leads to the rapid accumulation of heat,resulting in the formation of hot spots,which can cause the sintering or even deactivation of active species.To solve this problem,researchers have focused on monolithic catalysts with integrated reaction systems.This review categorizes the monolithic catalysts into two main groups based on their unique characteristics,namely structured catalysts and catalytic membrane reactors.The characteristics of these monolithic catalysts,commonly used support materials,preparation techniques,and their applications in the CO_(2) methanation reaction are discussed in depth.These studies provide theoretical basis and practical guidance for the design and optimization of structured catalysts and catalytic membrane reactors.Finally,challenges and prospects in the application of monolithic catalysts for the CO_(2) methanation reaction are proposed for the future development.展开更多
Electrochemical nitrogen reduction reaction(ENRR)is emerging as a favorable option to the power-intensive Haber-Bosch process for ammonia synthesis.However,obstacles such as poor selectivity,low production rates,and c...Electrochemical nitrogen reduction reaction(ENRR)is emerging as a favorable option to the power-intensive Haber-Bosch process for ammonia synthesis.However,obstacles such as poor selectivity,low production rates,and competition against the hydrogen evolution reaction hinder its practical implementation.To address these,the design of highly active catalysts is critical.Single-atom catalysts(SACs)have shown great potential because of their maximized atom utilization,but their limited stability and low metal loading restrict their performances.On the other hand,dual-atom catalysts(DACs)are atomic catalysts with two metal atoms nearby and offer enhanced electrocatalytic performances by aligning with the N≡N bond to enhance N2 reduction efficiency,potentially overcoming the limitations of SAC.This review discusses recent advances in SACs and more importantly DACs for ENRR,highlighting their advantages,limitations,and the need for advanced characterization techniques to better understand catalyst behavior.The review concludes by underscoring the importance of research to optimize these catalysts for efficient and sustainable nitrogen fixation.展开更多
Carbon monoxide(CO)oxidation is crucial for pollutant removal and hydrogen purification.In recent years,copper–cerium(Cu–Ce)-mixed oxide catalysts have attracted significant attention due to their excellent activity a...Carbon monoxide(CO)oxidation is crucial for pollutant removal and hydrogen purification.In recent years,copper–cerium(Cu–Ce)-mixed oxide catalysts have attracted significant attention due to their excellent activity and stability in CO oxida-tion.This study presents an innovative,environmentally friendly electrosynthesis method for producing stable,structured Cu–Ce catalysts in mesh form.This approach addresses the limitations of traditional pellet catalysts,such as fragility and poor thermal conductivity.The results demonstrated that incorporating cerium(Ce)enhanced the catalytic activity for CO oxidation threefold.A series of in situ characterizations revealed that the introduction of Ce led to the formation of a Cu–Ce mixed oxide solid solution,which significantly improved catalytic performance.Furthermore,higher pretreatment tem-peratures facilitated the decomposition of Ce compounds(nitrate and hydroxide),which promotes the formation of Cu–Ce solid solutions and increases the concentration of active intermediate species(Cu^(+)-CO)during the reaction.This process ultimately enhanced the catalyst’s activity.展开更多
Catalyzed gasoline particulate filters(cGPFs)are being developed to enable compliance with the particulate number limits for passenger cars equipped with gasoline direct injection(GDI)engines in China and Europe,It is...Catalyzed gasoline particulate filters(cGPFs)are being developed to enable compliance with the particulate number limits for passenger cars equipped with gasoline direct injection(GDI)engines in China and Europe,It is appealing to build catalysts with ceria—an irreplaceable"reducible"component in three-way converters—to help eliminate the soot particles trapped in cGPFs via O_(2)-assisted combustion.While research aiming at understanding how these recipes function has continued for more than two decades,a universal model elucidating the roles of different"active oxygen"species is yet to be realized.In this perspective,by critically assessing the reported data about gasoline soot catalytic combustion over ceria catalysts,it is suggested that ceria ignites soot through contributing its lattice oxygen,giving rise to a"hot ring"region at the periphery of soot-catalyst interface.During the"re-oxidation"semi-cycles,electrophilic superoxides and/or peroxides(O_(x)^(n-))are produced at the Ce^(3+)and oxygen vacancy sites enriched in this collar-like region,and then work as key reactive phases for soot deep oxidation.Based on this"O_(x)^(n-)assisted"Mars-van Krevelen mechanism,several guidelines for ceria catalyst designing are proposed,ending with a summary about where future opportunities and challenges may lie in developing efficient and practical cGPF catalysts.展开更多
The selective addition reaction of unsaturated C-C bonds has always been a classic and constant research topic.Different from well-developed hydroboration,hydrosilylation,and hydrostannylation reaction,hydrogermylatio...The selective addition reaction of unsaturated C-C bonds has always been a classic and constant research topic.Different from well-developed hydroboration,hydrosilylation,and hydrostannylation reaction,hydrogermylation reaction remains challenging which hasn't been much reported.Herein,we developed a new metal-porous ligand polymers Pd1@POL-PPh_(n)Cy_(m)(n+m=3)with monoatomic dispersion characteristics for highly selective and efficient hydrogermylation of unsaturated C-C bonds,including alkynes,alkenes,and allenes.X-ray photoelectron spectroscopy and theoretical calculations further proved the introduction of cyclohexyl could gently adjust the charge on monoatomic Pd center which effectively facilitate the recognition and transformation of various substrates.With the electrically fine-tuned single atom palladium catalysts,we realized theα-germanium addition for the first time,obtaining corresponding allyl germanium and alkyl germanium compounds.展开更多
基金Supported by the National Key Research and Development Program of China(2023YFB4104500,2023YFB4104502)the National Natural Science Foundation of China(22138013)the Taishan Scholar Project(ts201712020).
文摘Against the backdrop of escalating global climate change and energy crises,the resource utilization of carbon dioxide(CO_(2)),a major greenhouse gas,has become a crucial pathway for achieving carbon peaking and carbon neutrality goals.The hydrogenation of CO_(2)to methanol not only enables carbon sequestration and recycling,but also provides a route to produce high value-added fuels and basic chemical feedstocks,holding significant environmental and economic potential.However,this conversion process is thermodynamically and kinetically limited,and traditional catalyst systems(e.g.,Cu/ZnO/Al_(2)O_(3))exhibit inadequate activity,selectivity,and stability under mild conditions.Therefore,the development of novel high-performance catalysts with precisely tunable structures and functionalities is imperative.Metal-organic frameworks(MOFs),as crystalline porous materials with high surface area,tunable pore structures,and diverse metal-ligand compositions,have the great potential in CO_(2)hydrogenation catalysis.Their structural design flexibility allows for the construction of well-dispersed active sites,tailored electronic environments,and enhanced metal-support interactions.This review systematically summarizes the recent advances in MOF-based and MOF-derived catalysts for CO_(2)hydrogenation to methanol,focusing on four design strategies:(1)spatial confinement and in situ construction,(2)defect engineering and ion-exchange,(3)bimetallic synergy and hybrid structure design,and(4)MOF-derived nanomaterial synthesis.These approaches significantly improve CO_(2)conversion and methanol selectivity by optimizing metal dispersion,interfacial structures,and reaction pathways.The reaction mechanism is further explored by focusing on the three main reaction pathways:the formate pathway(HCOO*),the RWGS(Reverse Water Gas Shift reaction)+CO*hydrogenation pathway,and the trans-COOH pathway.In situ spectroscopic studies and density functional theory(DFT)calculations elucidate the formation and transformation of key intermediates,as well as the roles of active sites,metal-support interfaces,oxygen vacancies,and promoters.Additionally,representative catalytic performance data for MOFbased systems are compiled and compared,demonstrating their advantages over traditional catalysts in terms of CO_(2)conversion,methanol selectivity,and space-time yield.Future perspectives for MOF-based CO_(2)hydrogenation catalysts will prioritize two main directions:structural design and mechanistic understanding.The precise construction of active sites through multi-metallic synergy,defect engineering,and interfacial electronic modulation should be made to enhance catalyst selectivity and stability.In addition,advanced in situ characterization techniques combined with theoretical modeling are essential to unravel the detailed reaction mechanisms and intermediate behaviors,thereby guiding rational catalyst design.Moreover,to enable industrial application,challenges related to thermal/hydrothermal stability,catalyst recyclability,and cost-effective large-scale synthesis must be addressed.The development of green,scalable preparation methods and the integration of MOF catalysts into practical reaction systems(e.g.,flow reactors)will be crucial for bridging the gap between laboratory research and commercial deployment.Ultimately,multi-scale structure-performance optimization and catalytic system integration will be vital for accelerating the industrialization of MOF-based CO_(2)-to-methanol technologies.
基金Supported by the Science and Technology Cooperation and Exchange special project of Cooperation of Shanxi Province(202404041101014)the Fundamental Research Program of Shanxi Province(202403021212333)+3 种基金the Joint Funds of the National Natural Science Foundation of China(U24A20555)the Lvliang Key R&D of University-Local Cooperation(2023XDHZ10)the Initiation Fund for Doctoral Research of Taiyuan University of Science and Technology(20242026)the Outstanding Doctor Funding Award of Shanxi Province(20242080).
文摘To elucidate the effect of calcite-regulated activated carbon(AC)structure on low-temperature denitrification performance of SCR catalysts,this work prepared a series of Mn-Ce/De-AC-xCaCO_(3)(x is the calcite content in coal)catalysts were prepared by the incipient wetness impregnation method,followed by acid washing to remove calcium-containing minerals.Comprehensive characterization and low-temperature denitrification tests revealed that calcite-induced structural modulation of coal-derived AC significantly enhances catalytic activity.Specifically,NO conversion increased from 88.3%of Mn-Ce/De-AC to 91.7%of Mn-Ce/De-AC-1CaCO_(3)(210℃).The improved SCR denitrification activity results from the enhancement of physicochemical properties including higher Mn^(4+)content and Ce^(4+)/Ce^(3+)ratio,an abundance of chemisorbed oxygen and acidic sites,which could strengthen the SCR reaction pathways(richer NH_(3)activated species and bidentate nitrate active species).Therefore,NO removal is enhanced.
基金supports from the National Natural Science Foundation of China(Grant Nos.12305372 and 22376217)the National Key Research&Development Program of China(Grant Nos.2022YFA1603802 and 2022YFB3504100)+1 种基金the projects of the key laboratory of advanced energy materials chemistry,ministry of education(Nankai University)key laboratory of Jiangxi Province for persistent pollutants prevention control and resource reuse(2023SSY02061)are gratefully acknowledged.
文摘Using photoelectrocatalytic CO_(2) reduction reaction(CO_(2)RR)to produce valuable fuels is a fascinating way to alleviate environmental issues and energy crises.Bismuth-based(Bi-based)catalysts have attracted widespread attention for CO_(2)RR due to their high catalytic activity,selectivity,excellent stability,and low cost.However,they still need to be further improved to meet the needs of industrial applications.This review article comprehensively summarizes the recent advances in regulation strategies of Bi-based catalysts and can be divided into six categories:(1)defect engineering,(2)atomic doping engineering,(3)organic framework engineering,(4)inorganic heterojunction engineering,(5)crystal face engineering,and(6)alloying and polarization engineering.Meanwhile,the corresponding catalytic mechanisms of each regulation strategy will also be discussed in detail,aiming to enable researchers to understand the structure-property relationship of the improved Bibased catalysts fundamentally.Finally,the challenges and future opportunities of the Bi-based catalysts in the photoelectrocatalytic CO_(2)RR application field will also be featured from the perspectives of the(1)combination or synergy of multiple regulatory strategies,(2)revealing formation mechanism and realizing controllable synthesis,and(3)in situ multiscale investigation of activation pathways and uncovering the catalytic mechanisms.On the one hand,through the comparative analysis and mechanism explanation of the six major regulatory strategies,a multidimensional knowledge framework of the structure-activity relationship of Bi-based catalysts can be constructed for researchers,which not only deepens the atomic-level understanding of catalytic active sites,charge transport paths,and the adsorption behavior of intermediate products,but also provides theoretical guiding principles for the controllable design of new catalysts;on the other hand,the promising collaborative regulation strategies,controllable synthetic paths,and the in situ multiscale characterization techniques presented in this work provides a paradigm reference for shortening the research and development cycle of high-performance catalysts,conducive to facilitating the transition of photoelectrocatalytic CO_(2)RR technology from the laboratory routes to industrial application.
文摘Supported metal catalysts are the backbone of heterogeneous catalysis,playing a crucial role in the modern chemical industry.Metal-support interactions(MSIs)are known important in determining the catalytic performance of supported metal catalysts.This is particularly true for single-atom catalysts(SACs)and pseudo-single-atom catalysts(pseudo-SACs),where all metal atoms are dispersed on,and interact directly with the support.Consequently,the MSI of SACs and pseudo-SACs are theoretically more sensitive to modulation compared to that of traditional nanoparticle catalysts.In this work,we experimentally demonstrated this hypothesis by an observed size-dependent MSI modulation.We fabricated CoFe_(2)O_(4) supported Pt pseudo-SACs and nanoparticle catalysts,followed by a straightforward water treatment process.It was found that the covalent strong metal-support interaction(CMSI)in pseudo-SACs can be weakened,leading to a significant activity improvement in methane combustion reaction.This finding aligns with our recent observation of CoFe_(2)O_(4) supported Pt SACs.By contrast,the MSI in Pt nanoparticle catalyst was barely affected by the water treatment,giving rise to almost unchanged catalytic performance.This work highlights the critical role of metal size in determining the MSI modulation,offering a novel strategy for tuning the catalytic performance of SACs and pseudo-SACs by fine-tuning their MSIs.
文摘The possibility and feasibility of using supercritical fluid СО<sub>2</sub> extraction process have been investigated and described in the book as part of the task of spent catalysts regeneration. The analysis of deactivating compounds has been carried out for industrial catalysts such as: 1) palladium catalyst G-58E of ethane-ethylene fraction hydrogenation;2) nickel/kieselguhr catalyst of process of separating acetylenic compounds from isoprene;3) active aluminum oxide catalyst of methyl phenyl carbinol dehydration process;4) palladium catalyst LD-265 of hydrocarbons hydrogenation process;5) nickel-molybdenum catalysts DN-3531 and Criterion 514 of kerosene hydrotreating process. The results of the study of catalyst deactivating compounds solubility in pure supercritical carbon dioxide and supercritical carbon dioxide are modified with polar additive. The results of the solubility study are described using the Peng-Robinson equation of state. The results of the implementation of the supercritical fluid СО<sub>2</sub> extraction process with respect to deactivated industrial catalyst samples have been provided. A comparison of the characteristics of samples of catalysts regenerated using the traditional approach and the SC-CO<sub>2</sub> extraction process has been conducted. The possibility of using supercritical fluid CO<sub>2</sub> impregnation process in the synthesis of a palladium catalyst has been investigated. The synthesis of palladium chloride-based organometallic complexes has been carried out. The results of the study of solubility thereof in supercritical carbon dioxide have been provided. A dynamic supercritical fluid CO<sub>2</sub> impregnation process condition has been implemented. A comparison of the characteristics of palladium catalyst samples synthesized using the conventional approach and SC-CO<sub>2</sub> impregnation process has been conducted and presented in the book.
基金supported by the National Natural Science Foundation of China(No.21571062)the Program for Professor of Special Appointment(Eastern Scholar)at the Shanghai Institutions of Higher Learning to JGL,and the Fundamental Research Funds for the Central Universities(No.222201717003)。
文摘Exploiting non-precious metal catalysts with excellent oxygen reduction reaction(ORR)performance for energy devices is paramount essential for the green and sustainable society development.Herein,low-cost,high-performance biomass-derived ORR catalysts with an asymmetric Fe-N_(3)P configuration was prepared by a simple pyrolysis-etching technique,where carboxymethyl cellulose(CMC)was used as the carbon source,urea and 1,10-phenanthroline iron complex(FePhen)as additives,and Na_(3)PO_(4)as the phosphorus dopant and a pore-forming agent.The CMC-derived FeNPC catalyst displayed a large specific area(BET:1235 m^(2)g^(-1))with atomically dispersed Fe-N_(3)P active sites,which exhibited superior ORR activity and stability in alkaline solution(E_(1/2)=0.90 V vs.RHE)and Zn-air batteries(P_(max)=149 mW cm^(-2))to commercial Pt/C catalyst(E_(1/2)=0.87 V,P_(max)=118 mW cm^(-2))under similar experimental conditions.This work provides a feasible and costeffective route toward highly efficient ORR catalysts and their application to Zn-air batteries for energy conversion.
基金the Canadian NRCan OERD Energy Innovation Programthe Natural Sciences and Engineering Research Council of Canada,and the Carbon Solution Program for their financial support.
文摘The pursuit of alternative fuel generation technologies has gained momentum due to the diminishing reserves of fossil fuels and global warming from increased CO_(2)emission.Among the proposed methods,the hydrogenation of CO_(2)to produce marketable carbon-based products like methanol and ethanol is a practical approach that offers great potential to reduce CO_(2)emissions.Although significant volumes of methanol are currently produced from CO_(2),developing highly efficient and stable catalysts is crucial for further enhancing conversion and selectivity,thereby reducing process costs.An in-depth examination of the differences and similarities in the reaction pathways for methanol and ethanol production highlights the key factors that drive C-C coupling.Identifying these factors guides us toward developing more effective catalysts for ethanol synthesis.In this paper,we explore how different catalysts,through the production of various intermediates,can initiate the synthesis of methanol or ethanol.The catalytic mechanisms proposed by spectroscopic techniques and theoretical calculations,including operando X-ray methods,FTIR analysis,and DFT calculations,are summarized and presented.The following discussion explores the structural properties and composition of catalysts that influence C-C coupling and optimize the conversion rate of CO_(2)into ethanol.Lastly,the review examines recent catalysts employed for selective methanol and ethanol production,focusing on single-atom catalysts.
基金financial support from the National Research Council of Science&Technology(NST)grant funded by the Ministry of Science and ICT,Republic of Korea(CAP21012-100)the Korea Institute of Energy Technology Evaluation and Planning(KETEP),under the Ministry of Trade,Industry&Energy(MOTIE),Republic of Korea(20224C10300010)the KETEP grant funded by the MOTIE(20224000000440,Sector coupling energy industry advancement manpower training program)。
文摘The metal oxide promoter decisively influences the overall performance of Fe catalysts in the direct hydrogenation of CO_(2)to C_(5+)hydrocarbons.However,the roles of metal oxide promoter for Fe catalysts,particularly ZrO_(2),have rarely been investigated.To plug this knowledge gap,a new Fe catalyst promoted with Na and partially reduced ZrO_(x)(Na-FeZrO_(x-9))was developed in this study;the catalyst helped produce C_(5+)hydrocarbons in remarkably high yield(26.3%at 360℃).In contrast to ZrO_(x)-free Fe-oxide,NaFeZrO_(x)-9 exhibited long-term stability for CO_(2)hydrogenation(750 h on-stream).The findings revealed multiple roles of ZrO_(x).Notably,ZrO_(x)decorated the Fe-oxide particles after calcination,thereby suppressing excess particle aggregation during the reaction,and acted as a"coke remover"to eliminate the carbon deposited on the catalyst surface.Additionally,oxygen vacancy(O_(v))sites in ZrO_(x)and electron transfer from ZrO_(x)to Fe sites facilitated the adsorption of CO_(2)at the Zr-Fe interface.
基金Research Institute for Smart Energy(CDB2)the grant from the Research Institute for Advanced Manufacturing(CD8Z)+4 种基金the grant from the Carbon Neutrality Funding Scheme(WZ2R)at The Hong Kong Polytechnic Universitysupport from the Hong Kong Polytechnic University(CD9B,CDBZ and WZ4Q)the National Natural Science Foundation of China(22205187)Shenzhen Municipal Science and Technology Innovation Commission(JCYJ20230807140402006)Start-up Foundation for Introducing Talent of NUIST and Natural Science Foundation of Jiangsu Province of China(BK20230426).
文摘Catalyst–support interaction plays a crucial role in improving the catalytic activity of oxygen evolution reaction(OER).Here we modulate the catalyst–support interaction in polyaniline-supported Ni_(3)Fe oxide(Ni_(3)Fe oxide/PANI)with a robust hetero-interface,which significantly improves oxygen evolution activities with an overpotential of 270 mV at 10 mA cm^(-2)and specific activity of 2.08 mA cm_(ECSA)^(-2)at overpotential of 300 mV,3.84-fold that of Ni_(3)Fe oxide.It is revealed that the catalyst–support interaction between Ni_(3)Fe oxide and PANI support enhances the Ni–O covalency via the interfacial Ni–N bond,thus promoting the charge and mass transfer on Ni_(3)Fe oxide.Considering the excellent activity and stability,rechargeable Zn-air batteries with optimum Ni_(3)Fe oxide/PANI are assembled,delivering a low charge voltage of 1.95 V to cycle for 400 h at 10 mA cm^(-2).The regulation of the effect of catalyst–support interaction on catalytic activity provides new possibilities for the future design of highly efficient OER catalysts.
基金supported by Specific League Funds from Mahidol University,and partially supported by Office of the Permanent Secretary,Ministry of Higher Education,Science,Research and Inno-vation(OPS MHESI),Thailand Science Research and Innovation(TSRI)(Grant No.RGNS 63-167).
文摘Xylitol,one of the top twelve chemical building blocks,is commercially synthesized through the xylose hy-drogenation reaction using a metal catalyst.Biochar has emerged as an eco-efficient catalyst support material.In this study,biochar derived from corn stover(BCS)was first used as a metal catalyst support material for xylose hydrogenation into xylitol.The catalyst was prepared by carbonizing corn stover(CS),impregnating the resulting biochar with metal,and reducing the metal-impregnated BCS.The catalyst characteristics were comprehensively explored.The Ru/BCS catalyst was employed in xylose conversion to xylitol at different process temperatures(100-160℃),retention times(3-12 h),H_(2)pressures(2-5 MPa),and Ru contents(1-5%).The highest xylitol yield(87.0 wt.%)and selectivity(91.6%)were derived at 120℃ for 6 h under 4 MPa H_(2)using 5%Ru.Interestingly,the Ru/BCS catalyst showed high stability under the promising process condition.Additionally,xylitol production from hydrolysates enriched with CS xylose was subsequently explored.On the other hand,the catalyst characterization results revealed that the superior catalytic efficiency of 5Ru/BCS was mainly due to the metal nanoparticles embedded in the biochar.Additionally,BCS proved to be an outstanding support material for a bimetallic hydrogenation catalyst(Ru-Ni/BCS).Therefore,these results indicate that BCS can be a competitive support material for metal hydrogenation catalysts,enhancing environmental friendliness and potentially being employed in industrial-scale xylitol production.
基金financially supported by a PhD Grant from VITO’s Strategic Research Funds(No.2310345).
文摘Electrochemical CO_(2) reduction is a sustainable method for producing fuels and chemicals using renewable energy sources.Sn is a widely employed catalyst for formate production,with its performance closely influenced by the catalyst ink formulations and reac-tion conditions.The present study explores the influence of catalyst loading,current density,and binder choice on Sn-based CO_(2) reduc-tion systems.Decreasing catalyst loading from 10 to 1.685 mg·cm^(-2) and increasing current density in highly concentrated bicarbonate solutions significantly enhances formate selectivity,achieving 88%faradaic efficiency(FE)at a current density of−30 mA·cm^(-2) with a cathodic potential of−1.22 V vs.reversible hydrogen electrode(RHE)and a catalyst loading of 1.685 mg·cm^(-2).This low-loading strategy not only reduces catalyst costs but also enhances surface utilization and suppresses the hydrogen evolution reaction.Nafion enhances formate production when applied as a surface coating rather than pre-mixed in the ink,as evidenced by improved faradaic efficiency and lower cathodic potentials.However,this performance still does not match that of binder-free systems because Sn-based catalysts intrinsic-ally exhibit high catalytic activity,making the binder contribution less significant.Although modifying the electrode surface with binders leads to blocked active sites and increased resistance,polyvinylidene fluoride(PVDF)remains promising because of its stability,strength,and conductivity,achieving up to 72%FE to formate at−30 mA·cm^(-2) and−1.66 V vs.RHE.The findings of this research reveal method-ologies for optimizing the catalyst ink formulations and binder utilization to enhance the conversion of CO_(2) to formate,thereby offering crucial insights for the development of a cost-efficient catalyst for high-current-density operations.
基金supported by the National Key Research and Development Program of China(2024YFC3907904).
文摘Carbon-supported mercury catalysts are extensivelyemployed in calcium carbide-based polyvinyl chloride(PVC)industries,but the usage of mercury-based catalysts can pose an environmental threat due to the release of mercury into the surrounding area during the operation period.In this study,a highly active and stable mercury-based catalyst was developed,utilizing the nitrogen atom of the support as the anchor site to enhance the interaction between active sites(HgCl_(2))and the carbon support(N-AC).Thermal loss rate testing and thermogravimetric analysis results demonstrate that,compared to commercial activated carbon,N-doped carbon can effectively increase the heat stability of HgCl_(2).The obtained mercury-based catalysts(HgCl_(2)/N-AC)exhibit significant catalytic performance,achieving 2.5 times the C2H2 conversion of conventional HgCl_(2)/AC catalysts.Experimental analysis combined with theoretical calculations reveals that,contrary to the Eley-Rideal(ER)mechanism of HgCl_(2)/AC,the HgCl_(2)/N-AC catalyst follows the Langmuir-Hinshelwood(LH)adsorption mechanism.The nitrogen sites and HgCl_(2) on the catalyst enhance the adsorption capabilities of the HCl and C2H2,thereby improving the catalytic performance.Based on the modification of the active center by these solid ligands,the loading amount of HgCl_(2) on the catalyst can be further reduced from the current 6.5%to 3%.Considering the absence of successful industrial applications for mercury-free catalysts,and based on the current annual consumption of commercial mercury chloride catalysts in the PVC industry,the widespread adoption of this technology could annually reduce the usage of chlorine mercury by 500 tons,making a notable contribution to mercury compliance,reduction,and emissions control in China.It also serves as a bridge between mercury-free and low-mercury catalysts.Moreover,this solid ligand technology can assist in the application research of mercury-free catalysts.
基金supported by Foshan Xianhu Laboratory Project(No.XHD2024–31000000–06)Guangdong Basic and Applied Basic Research Foundation(Nos.2024A1515140005,2024B1515120017)National Natural Science Foundation of China(No.22308070).
文摘Electrocatalytic C–N coupling technology offers a promising route for green and sustainable urea synthesis.However,this route faces challenges of low urea yield and Faradaic efficiency due to the high dissociation energy of atomic bonds in reactants,complex reaction intermediates,high reaction energy barriers,and competing side reactions.As C–N coupling involves the synergistic action of two or more active sites,it is crucial to develop efficient multi-active-site catalysts to address these challenges.This review analyzes the reaction mechanisms of electrocatalytic C–N coupling for urea synthesis and summarizes effective strategies to achieve multi-active-site catalysts,including heteroatom doping,defect engineering,heterojunctions,and diatomic catalysts.Furthermore,based on this analysis,we propose the universal design principles for high-efficiency multi-activesite catalysts.
文摘Single-atom catalysts(SACs),in which isolated metal atoms such as palladium(Pd)are anchored on solid supports,promise breakthroughs in energy conversion and catalysis.However,balancing their activity(reaction speed)and stability(longevity)remains challenging,as the interplay between metal atoms,supports,and reactants is poorly understood.
基金supported by the National Natural Science Foundation of China(21603054,31671930)the Natural Science Foundation of Hebei Province(B2016204136,B2016204131)+3 种基金the Young Top-notch Talents Foundation of Hebei Provincial Universities(BJ2016027)the Innovation and entrepreneurship training program for college students of Hebei Agricultural University(s202010086046,2019085)the Scientific Research Development Fund project of Hebei Agricultural University(JY2020028)the Innovation and entrepreneurship training program for college students of Hebei Agricultural University(2025019,2025198).
文摘The development of formic acid dehydrogenation materials with high activity and low cost is key to realizing hydrogen energy utilization.Herein,we describe a specific low-loading strategy to construct a high-activity Co atom site catalyst for this reaction.Under optimal conditions,the formic acid dehydrogenation performance of Co─Fe dual-atom catalyst(turnover frequency of 2,446.8 h^(−1),hydrogen production rate of 1,015,306.1 mL gCo^(−1)h^(−1))was 300 times greater than that of commercial 5%Pd/C.High-angle annular dark-field scanning transmission electron microscopy and X-ray absorption fine structure spectra,combined with theoretical calculations,confirm that the presence of different active sites(Co single-atom,Co-Co dual-atom,Co─Fe dual-atom)in catalysts is the key factor affecting their catalytic activity.These findings provide a strong scientific basis for the development of single-atom and dual-atom catalysts.
基金the National Natural Science Foundation of China(22325804 and 22308148)the Natural Science Foundation of Jiangsu Province(BK20230344)+1 种基金the Natural Science Research Project of Jiangsu University(22KJB610001)the Jiangsu Funding Program for Excellent Postdoctoral Talent(2023ZB505)。
文摘Carbon dioxide(CO_(2))can be efficiently converted and utilized through the CO_(2) methanation reaction,which has significant potential benefits for the environment and the economy.The contradiction between the thermodynamics and kinetics of the CO_(2) methanation reaction process leads to low CO_(2) conversion at 200-350℃and low methane selectivity at 350-500℃.The utilization of catalysts can solve the contradiction between kinetics and thermodynamics,achieving high CO_(2) methanation efficiency at low temperatures.However,the poor thermal conductivity of powder catalysts leads to the rapid accumulation of heat,resulting in the formation of hot spots,which can cause the sintering or even deactivation of active species.To solve this problem,researchers have focused on monolithic catalysts with integrated reaction systems.This review categorizes the monolithic catalysts into two main groups based on their unique characteristics,namely structured catalysts and catalytic membrane reactors.The characteristics of these monolithic catalysts,commonly used support materials,preparation techniques,and their applications in the CO_(2) methanation reaction are discussed in depth.These studies provide theoretical basis and practical guidance for the design and optimization of structured catalysts and catalytic membrane reactors.Finally,challenges and prospects in the application of monolithic catalysts for the CO_(2) methanation reaction are proposed for the future development.
基金supported by the National Research Foundation of Korea(2022R1C1C2005786,RS-2023-00256106,RS-2023-00207831,RS-2024-00346153).
文摘Electrochemical nitrogen reduction reaction(ENRR)is emerging as a favorable option to the power-intensive Haber-Bosch process for ammonia synthesis.However,obstacles such as poor selectivity,low production rates,and competition against the hydrogen evolution reaction hinder its practical implementation.To address these,the design of highly active catalysts is critical.Single-atom catalysts(SACs)have shown great potential because of their maximized atom utilization,but their limited stability and low metal loading restrict their performances.On the other hand,dual-atom catalysts(DACs)are atomic catalysts with two metal atoms nearby and offer enhanced electrocatalytic performances by aligning with the N≡N bond to enhance N2 reduction efficiency,potentially overcoming the limitations of SAC.This review discusses recent advances in SACs and more importantly DACs for ENRR,highlighting their advantages,limitations,and the need for advanced characterization techniques to better understand catalyst behavior.The review concludes by underscoring the importance of research to optimize these catalysts for efficient and sustainable nitrogen fixation.
基金supported by the National Key R&D Program of China(No.2022YFB3805504)the National Natu-ral Science Foundation of China(No.22078089)+2 种基金the Shanghai Pilot Program for Basic Research(No.22TQ1400100-7)the Basic Research Program of Science and Technology Commission of Shanghai Munici-pality(No.22JC1400600)the Fundamental Research Funds for the Central Universities.
文摘Carbon monoxide(CO)oxidation is crucial for pollutant removal and hydrogen purification.In recent years,copper–cerium(Cu–Ce)-mixed oxide catalysts have attracted significant attention due to their excellent activity and stability in CO oxida-tion.This study presents an innovative,environmentally friendly electrosynthesis method for producing stable,structured Cu–Ce catalysts in mesh form.This approach addresses the limitations of traditional pellet catalysts,such as fragility and poor thermal conductivity.The results demonstrated that incorporating cerium(Ce)enhanced the catalytic activity for CO oxidation threefold.A series of in situ characterizations revealed that the introduction of Ce led to the formation of a Cu–Ce mixed oxide solid solution,which significantly improved catalytic performance.Furthermore,higher pretreatment tem-peratures facilitated the decomposition of Ce compounds(nitrate and hydroxide),which promotes the formation of Cu–Ce solid solutions and increases the concentration of active intermediate species(Cu^(+)-CO)during the reaction.This process ultimately enhanced the catalyst’s activity.
基金supported by the National Natural Science Foundation of China(22076176,22276106)the Natural Science Foundation of Shandong Province(ZR2021YQ14)+3 种基金the Innovation Ability Improvement Project for Technology-based Small-and Medium-sized Enterprises of Shandong Province(2022TSGC1345)Jiangsu Province Science and Technology Plan Special Fund(BZ2022053)Key Research and Development Program of Anhui Province(202104g01020006)the Fundamental Research Funds for the Central Universities(202141008)。
文摘Catalyzed gasoline particulate filters(cGPFs)are being developed to enable compliance with the particulate number limits for passenger cars equipped with gasoline direct injection(GDI)engines in China and Europe,It is appealing to build catalysts with ceria—an irreplaceable"reducible"component in three-way converters—to help eliminate the soot particles trapped in cGPFs via O_(2)-assisted combustion.While research aiming at understanding how these recipes function has continued for more than two decades,a universal model elucidating the roles of different"active oxygen"species is yet to be realized.In this perspective,by critically assessing the reported data about gasoline soot catalytic combustion over ceria catalysts,it is suggested that ceria ignites soot through contributing its lattice oxygen,giving rise to a"hot ring"region at the periphery of soot-catalyst interface.During the"re-oxidation"semi-cycles,electrophilic superoxides and/or peroxides(O_(x)^(n-))are produced at the Ce^(3+)and oxygen vacancy sites enriched in this collar-like region,and then work as key reactive phases for soot deep oxidation.Based on this"O_(x)^(n-)assisted"Mars-van Krevelen mechanism,several guidelines for ceria catalyst designing are proposed,ending with a summary about where future opportunities and challenges may lie in developing efficient and practical cGPF catalysts.
基金supported by the National Natural Science Foundation of China(Nos.22201049,22471046)the Ba-Gui Youth Top-notch Talents Project of Guangxithe National HighLevel Personnel of Special Support Program for Young Top-notch Talents(9th batch)。
文摘The selective addition reaction of unsaturated C-C bonds has always been a classic and constant research topic.Different from well-developed hydroboration,hydrosilylation,and hydrostannylation reaction,hydrogermylation reaction remains challenging which hasn't been much reported.Herein,we developed a new metal-porous ligand polymers Pd1@POL-PPh_(n)Cy_(m)(n+m=3)with monoatomic dispersion characteristics for highly selective and efficient hydrogermylation of unsaturated C-C bonds,including alkynes,alkenes,and allenes.X-ray photoelectron spectroscopy and theoretical calculations further proved the introduction of cyclohexyl could gently adjust the charge on monoatomic Pd center which effectively facilitate the recognition and transformation of various substrates.With the electrically fine-tuned single atom palladium catalysts,we realized theα-germanium addition for the first time,obtaining corresponding allyl germanium and alkyl germanium compounds.
