H_2O_(2) is one of the most important chemicals in the world.Recently,the electrochemical synthesis of H_2O_(2)by two-electron oxygen reduction reaction(2e^(-)ORR)has attracted great interest.Carbon-based catalysts sh...H_2O_(2) is one of the most important chemicals in the world.Recently,the electrochemical synthesis of H_2O_(2)by two-electron oxygen reduction reaction(2e^(-)ORR)has attracted great interest.Carbon-based catalysts show great promise for electrocatalytic production of H_2O_(2),due to the ease of regulation of the carbon materials with regard to the pore structure,surface properties,and heteroatom doping.Biomass as the carbon precursor has the advantages of low cost,sustainable supply,and extensive availability.Conversion of biomass to functional carbon-based materials shows the attractive merits,such as low carbon emission in the life cycle and diversity of the obtained carbon materials due to the wide source of biomass feedstocks.In this article,a comprehensive review on the mechanisms and processes of electrochemical synthesis of H_2O_(2) by 2e^(-)ORR over carbon-based catalysts is provided.The potential biomass feedstock used for obtaining the carbon-based catalysts,and the strategies to prepare the catalysts by carbonization and heteroatom doping,as well as optimization of electrodes and design of electrolyzer,are discussed.It is recommended that future work focus on developing efficient methods to prepare the catalysts from low-cost biomass feedstock,understanding the mechanisms of 2e^(-)ORR over the catalysts,optimization of electrode materials loaded with biomass-derived catalysts,as well as development of electrolyzers for larger-scale applications.展开更多
Using Cu-BTC prepared by hydrothermal method as precursor, carbon-based catalysts were obtained as model materials for low-temperature DeNO_x. These catalysts were characterized by X-ray diffractometry(XRD), Raman s...Using Cu-BTC prepared by hydrothermal method as precursor, carbon-based catalysts were obtained as model materials for low-temperature DeNO_x. These catalysts were characterized by X-ray diffractometry(XRD), Raman spectroscopy, scanning electron microscopy(SEM) and energy dispersive X-ray spectrometry(EDS). The results showed that all carbon-based catalysts held the octahedron shape of Cu-BTC in most parts, and they mainly consisted of face-centered cubic copper. CuO_x/C exhibited excellent catalytic activity, and such catalytic activity was further improved with the introduction of Ag. The catalyst with a Cu to Ag mole ratio of 6:1 and an activated temperature of 600 °C showed the best catalytic performance, and its catalytic denitration rate reached 100% at a temperature as low as 235 °C. During the catalytic reaction process, Cu~+ mainly played a catalytic role.展开更多
The continuous depletion of fossil fuels and the effects of climate change have encouraged prompt action to attain carbon neutrality.Technologies that transform and store renewable energy are crucial for creating a su...The continuous depletion of fossil fuels and the effects of climate change have encouraged prompt action to attain carbon neutrality.Technologies that transform and store renewable energy are crucial for creating a sustainable society,which is independent of fossil fuels.In this regard,electrochemical water splitting based on the oxygen evolution reaction(OER)and hydrogen evolution reaction(HER)is an attractive technique for producing carbon-free hydrogen fuels.Additionally,rechargeable metal–air batteries(MABs)are another intriguing way for renewable energy storage through reversible oxygen reactions(OER and the oxygen reduction reaction,ORR).Herein,we comprehensively review bifunctional electrocatalysts for water splitting(HER and OER)and MABs(OER and ORR),particularly 2D carbon material-derived heterostructures.The synthesis and properties of 2D carbon materials and their energy conversion and storage mechanisms are discussed to highlight the bifunc-tionality of the heterostructures.Recent studies on bifunctional electrocatalysts based on 2D carbon-derived heterostructures are also reviewed.Finally,perspectives for future studies and multifunctional catalysts are presented.展开更多
Hydrogen peroxide(H_(2)O_(2))is an essential environmentally friendly oxidant with a wide range of applications.Compared with traditional anthraquinone processes,the electrochemical synthesis of H_(2)O_(2)via the two-...Hydrogen peroxide(H_(2)O_(2))is an essential environmentally friendly oxidant with a wide range of applications.Compared with traditional anthraquinone processes,the electrochemical synthesis of H_(2)O_(2)via the two-electron oxygen reduction reaction and two-electron water oxidation reaction offers a more promising and sustainable alternative.Carbon-based electrocatalysts playing a crucial role in these processes owing to their abundance and facile functionalization.This review focuses on the strategic design of carbon-based electrocatalysts to enhance H_(2)O_(2)production.We begin by highlighting the significance of H_(2)O_(2)and the fundamental mechanisms of electrochemical process.Subsequently,we present a detailed analysis of key factors affecting catalytic performance,concentrating electronic structure and geometric structure regulation as primary catalyst design approaches to improve H_(2)O_(2)production.Interface engineering and pH effects are also emphasized for their crucial roles.Finally,the major challenges and prospects for advancing H_(2)O_(2)production towards practical applications are discussed.展开更多
In this paper,the Ni/Al_(2)O_(3) monolithic catalyst with 15%Ni content was prepared using cordierite as a matrix,and the catalyst was modified with 10%NaOH to study the methanation performance of biomass gasification...In this paper,the Ni/Al_(2)O_(3) monolithic catalyst with 15%Ni content was prepared using cordierite as a matrix,and the catalyst was modified with 10%NaOH to study the methanation performance of biomass gasification simulated gas based on alkali-modified Ni/Al_(2)O_(3) monolithic catalyst.BET,TEM,H_(2)-TPR,XRD,CO_(2)-TPD and TG were used to characterize the physicochemical properties of the catalyst before and after modification.The results indicated that the CO conversion rate trends of unmodified and modified Ni/Al_(2)O_(3) monolithic catalysts over 2 h were fundamentally consistent.However,the Ni/Al_(2)O_(3) catalysts modified for 2 h demonstrated significantly enhanced performance compared to those modified for 1 h.Regarding CH4 selectivity,the modified Ni/Al_(2)O_(3) catalyst exhibited markedly better performance than the unmodified Ni/Al_(2)O_(3) catalyst,confirming the enhanced methane performance of the alkali-modified Ni/Al_(2)O_(3) monolithic catalyst.Under optimized conditions(H_(2)/CO volume ratio of 3∶1,space velocity of 10000 mL/(g·h),and temperature of 400℃),the methanation performance of the Ni/Al_(2)O_(3) monolithic catalyst modified for 2 h reached its peak,achieving a CO conversion rate of 97%with 100%CH4 selectivity.展开更多
Electrochemical water splitting represents a sustainable technology for hydrogen(H_(2))production.However,its large-scale implementation is hindered by the high overpotentials required for both the cathodic hydrogen e...Electrochemical water splitting represents a sustainable technology for hydrogen(H_(2))production.However,its large-scale implementation is hindered by the high overpotentials required for both the cathodic hydrogen evolution reaction(HER)and the anodic oxygen evolution reaction(OER).Transition metal-based catalysts have garnered significant research interest as promising alternatives to noble-metal catalysts,owing to their low cost,tunable composition,and noble-metal-like catalytic activity.Nevertheless,systematic reviews on their application as bifunctional catalysts for overall water splitting(OWS)are still limited.This review comprehensively outlines the principal categories of bifunctional transition metal electrocatalysts derived from electrospun nanofibers(NFs),including metals,oxides,phosphides,sulfides,and carbides.Key strategies for enhancing their catalytic performance are systematically summarized,such as heterointerface engineering,heteroatom doping,metal-nonmetal-metal bridging architectures,and single-atom site design.Finally,current challenges and future research directions are discussed,aiming to provide insightful perspectives for the rational design of high-performance electrocatalysts for OWS.展开更多
Catalysts are key for olefin polymerization reactions and are also ubiquitous in catalysis science.Multinuclear metal catalysts have witnessed enhanced performances in catalytic reactions relative to mononuclear catal...Catalysts are key for olefin polymerization reactions and are also ubiquitous in catalysis science.Multinuclear metal catalysts have witnessed enhanced performances in catalytic reactions relative to mononuclear catalysts,but which substantially involve multi-step,tedious,and difficult synthesis.Herein,this study reports an intriguing approach to construct multi-nuclear catalysts for the milestoneα-diimine nickel catalysts using an oligomeric strategy.A polymerizable norbornene unit is incorporated into theα-diimine ligand backbone,leading to the formation of the monomeric nickel catalyst Ni_(1)and its corresponding oligomeric nickel catalysts(Ni_(3)and Ni_(5))with varying degrees of polymerization(DP=3 and 5).Notably,the oligomeric catalyst Ni_(5)was facilely scaled up(50 g-level),showed enhanced thermal stability,exhibited 4.6 times higher activity,and yielded polyethylene elastomer with a 379%increased molecular weight in ethylene polymerization,compared to the monomeric catalyst Ni_(1).Catalytic performance enhancements of oligomeric catalysts were found to be DP-dependent.The kilogram-scale polyethylene,produced using Ni_(5)in a 20 L reactor,presented a highly branched all-hydrocarbon structure,which demonstrated typical elastic properties(tensile strength:4 MPa,elastic recovery:SR=72%)along with great processability(MFI=3.0 g/10 min),insulating characteristics(volume resistivity=2×10^(16)Ω/m),and hydrophobicity(water vapor permeability:0.03 g/m^(2)/day),suggesting potentially practical applications.展开更多
Seawater zinc-air batteries are promising energy storage devices due to their high energy density and utilization of seawater electrolytes.However,their efficiency is hindered by the sluggish oxygen reduction reaction...Seawater zinc-air batteries are promising energy storage devices due to their high energy density and utilization of seawater electrolytes.However,their efficiency is hindered by the sluggish oxygen reduction reaction(ORR)and chlorideinduced degradation over conventional catalysts.In this study,we proposed a universal synthetic strategy to construct heteroatom axially coordinated Fe–N_(4) single-atom seawater catalyst materials(Cl–Fe–N_(4) and S–Fe–N_(4)).X-ray absorption spectroscopy confirmed their five-coordinated square pyramidal structure.Systematic evaluation of catalytic activities revealed that compared with S–Fe–N_(4),Cl–Fe–N_(4) exhibits smaller electrochemical active surface area and specific surface area,yet demonstrates higher limiting current density(5.8 mA cm^(−2)).The assembled zinc-air batteries using Cl–Fe–N_(4) showed superior power density(187.7 mW cm^(−2) at 245.1 mA cm^(−2)),indicating that Cl axial coordination more effectively enhances the intrinsic ORR activity.Moreover,Cl–Fe–N_(4) demonstrates stronger Cl−poisoning resistance in seawater environments.Chronoamperometry tests and zinc-air battery cycling performance evaluations confirmed its enhanced stability.Density functional theory calculations revealed that the introduction of heteroatoms in the axial direction regulates the electron center of Fe single atom,leading to more active reaction intermediates and increased electron density of Fe single sites,thereby enhancing the reduction in adsorbed intermediates and hence the overall ORR catalytic activity.展开更多
Single-atom catalysts(SACs)have demonstrated excellent performance in heterogeneous catalytic reactions owing to their maximized atomic efficiency,distinctive geometric,and electronic configurations.However,the effica...Single-atom catalysts(SACs)have demonstrated excellent performance in heterogeneous catalytic reactions owing to their maximized atomic efficiency,distinctive geometric,and electronic configurations.However,the efficacy of SACs remains limited for certain reactions requiring simultaneous activation of multiple reactants over metallic active sites.Herein,we report an atomically dispersed Pt1Ru1 dual-atom pair site anchored on nanodiamond@graphene(ND@G)for CO oxidation.The Pt1Ru1 dual-atom catalyst shows an exceptional turnover frequency(TOF)of 17.6.10^(-2)s^(-1)at significantly lower temperature(30℃),achieving a tenfold increase in TOF compared to singleatom Pt1/ND@G catalyst(1.5.10^(-2)s^(-1))and surpassing to previously reported Pt-based catalysts under similar conditions.Moreover,the catalyst demonstrates excellent stability,maintaining its activity for 40 h at 80℃without significant deactivation.The superior catalytic performance of Pt-Ru dual-atom catalysts is attributed to the synergistic effect between Pt and Ru atoms with enhanced metallicity for improving simultaneous adsorption and activation of CO and O_(2),and the tuning of conventional competitive reactant adsorption into a non-competitive pathway over dual-atom pair sites.The present work manifests the advantages of dual-atom pair sites in heterogeneous catalysis and paves the way for precise design of catalysts at the atomic scale.展开更多
Heterogeneous polymerization represents a widely employed method in the polyolefin industry.In recent years,various heterogenization strategies for late transition metal catalysts have been developed,enabling effectiv...Heterogeneous polymerization represents a widely employed method in the polyolefin industry.In recent years,various heterogenization strategies for late transition metal catalysts have been developed,enabling effective control of polymer morphology and optimization of catalytic performance.However,while most studies have focused on designing anchoring groups and advancing support approaches,systematic investigations into how the support influences the catalytic behavior of the late transition metal catalysts.In this work,we fabricated supported α-diimine nickel catalysts by functionalizing the ligand with alkyl alcohol chains of varying lengths and supporting them onto MgCl_(2)supports.The ethylene polymerization behavior of these catalysts was then investigated.By precisely adjusting the alkyl alcohol chain length,the distance between the catalytically active metal center and the support surface was modulated.This approach demonstrates that support-induced steric hindrance effect can be effectively regulated by controlling the separation distance between the metal center and the support surface.展开更多
Lithium-sulfur(Li-S)batteries boast a theoretical energy density as high as 2600 Wh·kg^(−1),positioning them as a highly attractive option for future advanced energy storage systems.Challenges such as slow transf...Lithium-sulfur(Li-S)batteries boast a theoretical energy density as high as 2600 Wh·kg^(−1),positioning them as a highly attractive option for future advanced energy storage systems.Challenges such as slow transformation kinetics and shuttle effects associated with lithium polysulfides(LiPSs)have seriously hindered their practical applications.In this paper,we present a new method for the synthesis of hollow carbon-sphere-supported Co monatomic catalysts(Co-N-C).This new synthesis method achieves pyrolytic coordination using a precursor rich in imide(-RC=N-)polymers.This synthesis method not only improves the adsorbability and catalytic activity of LiPS but also significantly weakens the shuttle effect and generates Co-N-C with superior conductivity,abundant hollow structures,and a high specific surface area,thus efficiently capturing and restricting the movement of LiPS intermediates.The dispersed Co monoatomic catalysts(Co SACs)were anchored to a highly conductive nitrogen-doped carbon framework and exhibited symmetric N-coordination active sites(Co-N_(4))to ensure fast redox kinetics of LiPS and Li_(2)S_(2)/Li_(2)S solid-state products.The lithium-sulfur battery with Co-N-C as the sulfur carrier showed excellent discharging capacity of 1146.6 mAh·g^(−1) at a discharge rate of 0.5 C and maintained excellent performance at a high discharge rate of 2 C.The capacity decay rate in 500 cycles was only 0.086%per cycle,reflecting excellent long-term cycle stability.This study highlights the key role of the synergistic effect between single-atom cobalt catalysts and hollow carbon spheres in enhancing the efficiency of lithium-sulfur(Li-S)batteries.It also provides valuable insights into the construction and fabrication of highly active monatomic catalysts.The catalytic conversion efficiency of lithium polysulfides is significantly enhanced when embedded in hollow carbon architectures,which serves as a critical strategy for optimizing the electrochemical behavior of next-generation Li-S batteries.展开更多
Methanol steam reforming(MSR)represents a promising route for hydrogen production,leveraging the high energy density and liquid-phase storage advantages of methanol.Copper-based catalysts have become indispensable for...Methanol steam reforming(MSR)represents a promising route for hydrogen production,leveraging the high energy density and liquid-phase storage advantages of methanol.Copper-based catalysts have become indispensable for MSR due to their cost-effectiveness,exceptional catalytic activity,and tunable selectivity.However,persistent challenges such as thermal sintering,undesirable CO byproduct formation,diminished low-temperature reactivity,and long-term catalyst deactivation limit their broad industrial deployment.This review comprehensively examines the mechanistic pathways of MSR over Cu-based catalysts,with particular focus on differentiating catalyst formulations optimized for high-temperature(>200°C)versus low-temperature(<200°C)operation.It highlights the decisive influence of Cu nanoparticle size,electronic structure,and crystal structure on catalytic performance.Cutting-edge design strategies,including multi-element engineering,innovative synthesis techniques,and deactivation mitigation,are critically evaluated to elucidate mechanistic connections between atomic-scale structure and catalytic performance enhancement.Finally,industrial applications of commercial Cu/ZnO/Al_(2)O_(3)variants and their scalability challenges are discussed,alongside prospective strategies for catalyst innovation and engineering to advance next-generation hydrogen production.展开更多
High‐entropy amorphous catalysts(HEACs)integrate multielement synergy with structural disorder,making them promising candidates for water splitting.Their distinctive features—including flexible coordination environm...High‐entropy amorphous catalysts(HEACs)integrate multielement synergy with structural disorder,making them promising candidates for water splitting.Their distinctive features—including flexible coordination environments,tunable electronic structures,abundant unsaturated active sites,and dynamic structural reassembly—collectively enhance electrochemical activity and durability under operating conditions.This review summarizes recent advances in HEACs for hydrogen evolution,oxygen evolution,and overall water splitting,highlighting their disorder-driven advantages over crystalline counterparts.Catalytic performance benchmarks are presented,and mechanistic insights are discussed,focusing on how multimetallic synergy,amorphization effect,and in‐situ reconstruction cooperatively regulate reaction pathways.These insights provide guidance for the rational design of next‐generation amorphous high‐entropy electrocatalysts with improved efficiency and durability.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
Developing metal-free, carbon-based catalysts to replace platinum-based catalysts for oxygen reduction reactions (ORRs) is an emerging area of research. In recent years, different carbon structures including carbon ...Developing metal-free, carbon-based catalysts to replace platinum-based catalysts for oxygen reduction reactions (ORRs) is an emerging area of research. In recent years, different carbon structures including carbon doped with IIIA-VIIA heteroatoms (C-M site-based, where M represents the doped heteroatom) and polynitrogen (PN) compounds encapsulated in carbon nanotubes (CNTs) (N N site-based) have been synthesized. Compared to metallic catalysts, these materials are highly active, stable, inexpensive, and environmentally friendly. This review discusses the development of these materials, their ORR performances and the mechanisms for how the incorpora- tion of heteroatoms enhances the ORR activity. Strategies for tailoring the structures of the carbon substrates to improve ORR performance are also discussed. Future studies in this area will need to include optimizing synthetic strategies to control the type, amount and distribution of the incorporated heteroatoms, as well as better understanding the ORR mechanisms in these catalysts.展开更多
Large-scale CO_(2)emissions have exacerbated the greenhouse effect,reinforcing the critical need for efficient CO_(2)mitigation methods.Plasma-catalytic technology enables CO_(2)conversion under mild conditions,especi...Large-scale CO_(2)emissions have exacerbated the greenhouse effect,reinforcing the critical need for efficient CO_(2)mitigation methods.Plasma-catalytic technology enables CO_(2)conversion under mild conditions,especially for CO_(2)methanation(the Sabatier reaction),which has attracted significant attention due to its economic benefits and the potential for safe energy transportation via existing natural gas pipelines.The development of high-performance CO_(2)methanation catalysts remains an ongoing and long-term objective,and there is a lack of adequate in-situ characterization techniques to investigate the mechanisms.This study focuses on the Ni/La_(2)O_(3)(LN)catalyst and introduces two CO_(2)activation strategies through F and Na modifications:the Ni-Ov-Ni site activation with electron transfer from Ni0 under low-power conditions and basic site activation under high-power conditions.The LN-NaF catalysts enhance CO_(2)methanation activity across the entire power range compared to LN,achieving a CO_(2)conversion of 86.3%and CH4 selectivity of 99.4%.Additionally,LN-F(h)reaches a CH4 yield 4.15 times higher than that of LN at low power.Furthermore,in-situ diffuse reflectance infrared Fourier transform(DRIFT)spectroscopy with a self-made reactor are performed under plasma-catalytic conditions to reveal the CO_(2)adsorption and conversion mechanisms,indicating that different dopants(F,Na,and NaF)exhibit promoting effects on different intermediates,resulting in variations in CO_(2)methanation activity.This study provides valuable insights for improving catalyst performance and a thorough comprehension of mechanisms in CO_(2)methanation.展开更多
Fuel cells are one of the most promising clean energy devices to substitute for fossil fuel in the future to alleviate energy crisis and environmental pollution.As the key reaction on the cathode in the fuel cells,oxy...Fuel cells are one of the most promising clean energy devices to substitute for fossil fuel in the future to alleviate energy crisis and environmental pollution.As the key reaction on the cathode in the fuel cells,oxygen reduction reaction(ORR)still requires efficient noble metal catalysts such as the comme rcial Pt/C to boost the reaction for its sluggish kinetics.Therefore,it is critical to design earth-abundant carbonbased catalysts with high efficiency and long-term stability to replace the noble metal-based catalysts.This review focuses on the recent progress about carbon-based ORR catalysts including non-metal doped carbon materials,transition metal-nitrogen-carbon species,transition metal carbides/carbon,single atom catalysts,and other carbon hybrids.And we further infer that the excellent ORR performances can be achieved by the balance of geometric and electronic structures of catalysts such as conductivity,surface area,hierarchical porous structure,defect and doping effect.Additionally,the perspective development trend is also proposed to guide the rational designation of carbon-based catalysts for ORR and even extend to other energy storage and conversion fields in the future.展开更多
Electrocatalytic carbon dioxide(CO_(2))reduction is an important way to achieve carbon neutrality by converting CO_(2)in-to high-value-added chemicals using electric energy.Carbon-based materials are widely used in va...Electrocatalytic carbon dioxide(CO_(2))reduction is an important way to achieve carbon neutrality by converting CO_(2)in-to high-value-added chemicals using electric energy.Carbon-based materials are widely used in various electrochemical reactions,including electrocatalytic CO_(2)reduction,due to their low cost and high activity.In recent years,defect engineering has attracted wide attention by constructing asymmetric defect centers in the materials,which can optimize the physicochemical properties of the mater-ial and improve its electrocatalytic activity.This review summarizes the types,methods of formation and defect characterization tech-niques of defective carbon-based materials.The advantages of defect engineering and the advantages and disadvantages of various defect formation methods and characterization techniques are also evaluated.Finally,the challenges of using defective carbon-based materials in electrocatalytic CO_(2)reduction are investigated and opportunities for their use are discussed.It is believed that this re-view will provide suggestions and guidance for developing defective carbon-based materials for CO_(2)reduction.展开更多
Proton exchange membrane fuel cell(PEMFC)has important implications for the success of clean transportation in the future.One of the key factors affecting the cost and performance of PEMFC is the cathode electrocataly...Proton exchange membrane fuel cell(PEMFC)has important implications for the success of clean transportation in the future.One of the key factors affecting the cost and performance of PEMFC is the cathode electrocatalyst for the oxygen reduction reaction(ORR)to overcome sluggish kinetics and instability in an acidic environment.As an essential component of the electrocatalyst,the support material largely determines the activity,mass transfer,charge transfer,and durability of the electrocatalyst.Thereby,the support material plays a critical role in the overall performance of the electrocatalyst.Carbonbased materials are widely used as electrocatalyst supports because of their high porosity,conductivity,chemical stability,and tunable morphology.Recently,some new carbon-based materials with excellent structure have been introduced,such as carbon nanotubes,carbon nanowires,graphene,metal-organic framework(MOF)-derived carbon,and biomass-derived carbon materials.Combined with a variety of strategies,such as controllable construction of porous structures and surface defects,proper doping heteroatoms,the ingenious design of model electrocatalysts,and predictive theoretical calculation,a new reliable path was provided for further improving the performance of electrocatalysts and exploring the catalytic mechanism.Based on the topic of carbon-based materials for ORR in acidic medium,this review summarizes the up-to-date progress and breakthroughs,highlights the factors affecting the catalytic activity and stability of ORR electrocatalysts in acids,and discusses their future application and development.展开更多
The electrochemical production of hydrogen peroxide(H_(2)O_(2))by the two-electron oxygen reduction(2e^(-)-ORR)process has the advantages of high safety,low energy consumption,and environmental friendliness.For 2e^(-)...The electrochemical production of hydrogen peroxide(H_(2)O_(2))by the two-electron oxygen reduction(2e^(-)-ORR)process has the advantages of high safety,low energy consumption,and environmental friendliness.For 2e^(-)-ORR,the catalyst/electrode is the key component as it strongly affects catalytic performance and cost.Carbon materials have the advantages of high electronic conductivity,good structural stability,easy control of nanostructures,and low cost.Therefore,it has been regarded as a promising catalyst/electrode material for the electrosynthesis of H_(2)O_(2)via 2e^(-)-ORR.In addition,studies have also considered the optimization of the liquid/gas interface by tuning the electrode surface,electrolyte pH,and reactor configurations for further improving the activity and selectivity of catalysts.In this review,we provide an in-depth discussion of the recent research on the carbon-based electrocatalysts for 2e^(-)ORR,especially in terms of microenvironment tuning,catalyst/electrode interface engineering,and reactor design for achieving stable and efficient production of H_(2)O_(2).The challenges that we are still facing and the future development prospects will then be concluded,which we believe should help the future development in this field.展开更多
基金supported by the National Natural Science Foundation of China(Nos.22478222,22178197,and U23A6005)the Dr.Jentai Yang Sustainable Environmental Protection and Eco-humanistic Education Fund(No.20253000027)which isadministered by the Overseas Chinese Environmental Engineers and Scientists Association。
文摘H_2O_(2) is one of the most important chemicals in the world.Recently,the electrochemical synthesis of H_2O_(2)by two-electron oxygen reduction reaction(2e^(-)ORR)has attracted great interest.Carbon-based catalysts show great promise for electrocatalytic production of H_2O_(2),due to the ease of regulation of the carbon materials with regard to the pore structure,surface properties,and heteroatom doping.Biomass as the carbon precursor has the advantages of low cost,sustainable supply,and extensive availability.Conversion of biomass to functional carbon-based materials shows the attractive merits,such as low carbon emission in the life cycle and diversity of the obtained carbon materials due to the wide source of biomass feedstocks.In this article,a comprehensive review on the mechanisms and processes of electrochemical synthesis of H_2O_(2) by 2e^(-)ORR over carbon-based catalysts is provided.The potential biomass feedstock used for obtaining the carbon-based catalysts,and the strategies to prepare the catalysts by carbonization and heteroatom doping,as well as optimization of electrodes and design of electrolyzer,are discussed.It is recommended that future work focus on developing efficient methods to prepare the catalysts from low-cost biomass feedstock,understanding the mechanisms of 2e^(-)ORR over the catalysts,optimization of electrode materials loaded with biomass-derived catalysts,as well as development of electrolyzers for larger-scale applications.
基金Project(738010004)supported by the Project of Low Concentration Sulfur Dioxide Flue Gas Treatment,ChinaProject(2017GK4010)supported by the Scientific and Technological Breakthrough and Major Achievements Transformation of Strategic Emerging Industries of Hunan Province in 2017,China
文摘Using Cu-BTC prepared by hydrothermal method as precursor, carbon-based catalysts were obtained as model materials for low-temperature DeNO_x. These catalysts were characterized by X-ray diffractometry(XRD), Raman spectroscopy, scanning electron microscopy(SEM) and energy dispersive X-ray spectrometry(EDS). The results showed that all carbon-based catalysts held the octahedron shape of Cu-BTC in most parts, and they mainly consisted of face-centered cubic copper. CuO_x/C exhibited excellent catalytic activity, and such catalytic activity was further improved with the introduction of Ag. The catalyst with a Cu to Ag mole ratio of 6:1 and an activated temperature of 600 °C showed the best catalytic performance, and its catalytic denitration rate reached 100% at a temperature as low as 235 °C. During the catalytic reaction process, Cu~+ mainly played a catalytic role.
基金supported by National R&D Program through the National Research Foundation of Korea(NRF)funded by Ministry of Science and ICT(Nos.2022R1F1A1072420 and NRF-2020R1A3B2079803).
文摘The continuous depletion of fossil fuels and the effects of climate change have encouraged prompt action to attain carbon neutrality.Technologies that transform and store renewable energy are crucial for creating a sustainable society,which is independent of fossil fuels.In this regard,electrochemical water splitting based on the oxygen evolution reaction(OER)and hydrogen evolution reaction(HER)is an attractive technique for producing carbon-free hydrogen fuels.Additionally,rechargeable metal–air batteries(MABs)are another intriguing way for renewable energy storage through reversible oxygen reactions(OER and the oxygen reduction reaction,ORR).Herein,we comprehensively review bifunctional electrocatalysts for water splitting(HER and OER)and MABs(OER and ORR),particularly 2D carbon material-derived heterostructures.The synthesis and properties of 2D carbon materials and their energy conversion and storage mechanisms are discussed to highlight the bifunc-tionality of the heterostructures.Recent studies on bifunctional electrocatalysts based on 2D carbon-derived heterostructures are also reviewed.Finally,perspectives for future studies and multifunctional catalysts are presented.
基金funding supporting from the National Natural Science Foundation of China(Grant No.22125903,22439003,22309176)National Key R@D Program of China(Grants 2022YFA1504100)+2 种基金DICP(DICP I202471)the State Key Laboratory of Catalysis(No:2024SKL-A-001)Energy Revolution S&T Program of Yulin Innovation Institute of Clean Energy(Grant E412010508,Grant E411070316)。
文摘Hydrogen peroxide(H_(2)O_(2))is an essential environmentally friendly oxidant with a wide range of applications.Compared with traditional anthraquinone processes,the electrochemical synthesis of H_(2)O_(2)via the two-electron oxygen reduction reaction and two-electron water oxidation reaction offers a more promising and sustainable alternative.Carbon-based electrocatalysts playing a crucial role in these processes owing to their abundance and facile functionalization.This review focuses on the strategic design of carbon-based electrocatalysts to enhance H_(2)O_(2)production.We begin by highlighting the significance of H_(2)O_(2)and the fundamental mechanisms of electrochemical process.Subsequently,we present a detailed analysis of key factors affecting catalytic performance,concentrating electronic structure and geometric structure regulation as primary catalyst design approaches to improve H_(2)O_(2)production.Interface engineering and pH effects are also emphasized for their crucial roles.Finally,the major challenges and prospects for advancing H_(2)O_(2)production towards practical applications are discussed.
基金Supported by the National Natural Science Foundation of China(52506188,52476215)Natural Science Foundation of Liaoning Province(2024-MS-139,2024JH3/10200047)Scientific Research Program of Department of Education of Liaoning Province(310125042,LJ212410143033。
文摘In this paper,the Ni/Al_(2)O_(3) monolithic catalyst with 15%Ni content was prepared using cordierite as a matrix,and the catalyst was modified with 10%NaOH to study the methanation performance of biomass gasification simulated gas based on alkali-modified Ni/Al_(2)O_(3) monolithic catalyst.BET,TEM,H_(2)-TPR,XRD,CO_(2)-TPD and TG were used to characterize the physicochemical properties of the catalyst before and after modification.The results indicated that the CO conversion rate trends of unmodified and modified Ni/Al_(2)O_(3) monolithic catalysts over 2 h were fundamentally consistent.However,the Ni/Al_(2)O_(3) catalysts modified for 2 h demonstrated significantly enhanced performance compared to those modified for 1 h.Regarding CH4 selectivity,the modified Ni/Al_(2)O_(3) catalyst exhibited markedly better performance than the unmodified Ni/Al_(2)O_(3) catalyst,confirming the enhanced methane performance of the alkali-modified Ni/Al_(2)O_(3) monolithic catalyst.Under optimized conditions(H_(2)/CO volume ratio of 3∶1,space velocity of 10000 mL/(g·h),and temperature of 400℃),the methanation performance of the Ni/Al_(2)O_(3) monolithic catalyst modified for 2 h reached its peak,achieving a CO conversion rate of 97%with 100%CH4 selectivity.
基金Supported by the National Natural Science Foundation of China(No.52273056)the Science and Technology Development Program of Jilin Province,China(No.YDZJ202501ZYTS305)。
文摘Electrochemical water splitting represents a sustainable technology for hydrogen(H_(2))production.However,its large-scale implementation is hindered by the high overpotentials required for both the cathodic hydrogen evolution reaction(HER)and the anodic oxygen evolution reaction(OER).Transition metal-based catalysts have garnered significant research interest as promising alternatives to noble-metal catalysts,owing to their low cost,tunable composition,and noble-metal-like catalytic activity.Nevertheless,systematic reviews on their application as bifunctional catalysts for overall water splitting(OWS)are still limited.This review comprehensively outlines the principal categories of bifunctional transition metal electrocatalysts derived from electrospun nanofibers(NFs),including metals,oxides,phosphides,sulfides,and carbides.Key strategies for enhancing their catalytic performance are systematically summarized,such as heterointerface engineering,heteroatom doping,metal-nonmetal-metal bridging architectures,and single-atom site design.Finally,current challenges and future research directions are discussed,aiming to provide insightful perspectives for the rational design of high-performance electrocatalysts for OWS.
基金financial support from the National Natural Science Foundation of China(Nos.22401274,U23B6011)the Jilin Provincial Science and Technology Department Program(No.20250102070JC)。
文摘Catalysts are key for olefin polymerization reactions and are also ubiquitous in catalysis science.Multinuclear metal catalysts have witnessed enhanced performances in catalytic reactions relative to mononuclear catalysts,but which substantially involve multi-step,tedious,and difficult synthesis.Herein,this study reports an intriguing approach to construct multi-nuclear catalysts for the milestoneα-diimine nickel catalysts using an oligomeric strategy.A polymerizable norbornene unit is incorporated into theα-diimine ligand backbone,leading to the formation of the monomeric nickel catalyst Ni_(1)and its corresponding oligomeric nickel catalysts(Ni_(3)and Ni_(5))with varying degrees of polymerization(DP=3 and 5).Notably,the oligomeric catalyst Ni_(5)was facilely scaled up(50 g-level),showed enhanced thermal stability,exhibited 4.6 times higher activity,and yielded polyethylene elastomer with a 379%increased molecular weight in ethylene polymerization,compared to the monomeric catalyst Ni_(1).Catalytic performance enhancements of oligomeric catalysts were found to be DP-dependent.The kilogram-scale polyethylene,produced using Ni_(5)in a 20 L reactor,presented a highly branched all-hydrocarbon structure,which demonstrated typical elastic properties(tensile strength:4 MPa,elastic recovery:SR=72%)along with great processability(MFI=3.0 g/10 min),insulating characteristics(volume resistivity=2×10^(16)Ω/m),and hydrophobicity(water vapor permeability:0.03 g/m^(2)/day),suggesting potentially practical applications.
基金funded by the Innovative Research Group Project of the National Natural Science Foundation of China(52121004)the Research Development Fund(No.RDF-21-02-060)by Xi’an Jiaotong-Liverpool University+1 种基金support received from the Suzhou Industrial Park High Quality Innovation Platform of Functional Molecular Materials and Devices(YZCXPT2023105)the XJTLU Advanced Materials Research Center(AMRC).
文摘Seawater zinc-air batteries are promising energy storage devices due to their high energy density and utilization of seawater electrolytes.However,their efficiency is hindered by the sluggish oxygen reduction reaction(ORR)and chlorideinduced degradation over conventional catalysts.In this study,we proposed a universal synthetic strategy to construct heteroatom axially coordinated Fe–N_(4) single-atom seawater catalyst materials(Cl–Fe–N_(4) and S–Fe–N_(4)).X-ray absorption spectroscopy confirmed their five-coordinated square pyramidal structure.Systematic evaluation of catalytic activities revealed that compared with S–Fe–N_(4),Cl–Fe–N_(4) exhibits smaller electrochemical active surface area and specific surface area,yet demonstrates higher limiting current density(5.8 mA cm^(−2)).The assembled zinc-air batteries using Cl–Fe–N_(4) showed superior power density(187.7 mW cm^(−2) at 245.1 mA cm^(−2)),indicating that Cl axial coordination more effectively enhances the intrinsic ORR activity.Moreover,Cl–Fe–N_(4) demonstrates stronger Cl−poisoning resistance in seawater environments.Chronoamperometry tests and zinc-air battery cycling performance evaluations confirmed its enhanced stability.Density functional theory calculations revealed that the introduction of heteroatoms in the axial direction regulates the electron center of Fe single atom,leading to more active reaction intermediates and increased electron density of Fe single sites,thereby enhancing the reduction in adsorbed intermediates and hence the overall ORR catalytic activity.
基金supported by the National Key R&D Program of China (2021YFA1502802)the National Natural Science Foundation of China (U21B2092, 22202213, 22402210, 22502215, 22502214, 22572200, and 22579171)+3 种基金the International Partnership Program of Chinese Academy of Sciences (172GJHZ2022028MI)the Shenyang Bureau of Science and Technology (24-213-3-25)the Natural Science Foundation of Liaoning Province (2025BS0153)Zhongke Technology Achievement Transfer and Transformation Center of Henan Province 2025119
文摘Single-atom catalysts(SACs)have demonstrated excellent performance in heterogeneous catalytic reactions owing to their maximized atomic efficiency,distinctive geometric,and electronic configurations.However,the efficacy of SACs remains limited for certain reactions requiring simultaneous activation of multiple reactants over metallic active sites.Herein,we report an atomically dispersed Pt1Ru1 dual-atom pair site anchored on nanodiamond@graphene(ND@G)for CO oxidation.The Pt1Ru1 dual-atom catalyst shows an exceptional turnover frequency(TOF)of 17.6.10^(-2)s^(-1)at significantly lower temperature(30℃),achieving a tenfold increase in TOF compared to singleatom Pt1/ND@G catalyst(1.5.10^(-2)s^(-1))and surpassing to previously reported Pt-based catalysts under similar conditions.Moreover,the catalyst demonstrates excellent stability,maintaining its activity for 40 h at 80℃without significant deactivation.The superior catalytic performance of Pt-Ru dual-atom catalysts is attributed to the synergistic effect between Pt and Ru atoms with enhanced metallicity for improving simultaneous adsorption and activation of CO and O_(2),and the tuning of conventional competitive reactant adsorption into a non-competitive pathway over dual-atom pair sites.The present work manifests the advantages of dual-atom pair sites in heterogeneous catalysis and paves the way for precise design of catalysts at the atomic scale.
基金financially supported by the National Natural Science Foundation of China(No.52473338)the National Natural Science Foundation of China(Nos.52173004 and 51873055)+3 种基金Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDA0540000)Advanced Materials-National Science and Technology Major Project(No.2025ZD0614000)Hebei Natural Science Foundation(No.E2022202015)Anhui Province Science and Technology Innovation Tackling Key Project(No.202423i08050025)。
文摘Heterogeneous polymerization represents a widely employed method in the polyolefin industry.In recent years,various heterogenization strategies for late transition metal catalysts have been developed,enabling effective control of polymer morphology and optimization of catalytic performance.However,while most studies have focused on designing anchoring groups and advancing support approaches,systematic investigations into how the support influences the catalytic behavior of the late transition metal catalysts.In this work,we fabricated supported α-diimine nickel catalysts by functionalizing the ligand with alkyl alcohol chains of varying lengths and supporting them onto MgCl_(2)supports.The ethylene polymerization behavior of these catalysts was then investigated.By precisely adjusting the alkyl alcohol chain length,the distance between the catalytically active metal center and the support surface was modulated.This approach demonstrates that support-induced steric hindrance effect can be effectively regulated by controlling the separation distance between the metal center and the support surface.
基金supported by the National Natural Science Foundation of China(No.52064035)the Key Research and Development Program of Gansu Province,China(No.25YFGA024)the Natural Science Foundation of Zhejiang Province,China(No.LGG22E020003).
文摘Lithium-sulfur(Li-S)batteries boast a theoretical energy density as high as 2600 Wh·kg^(−1),positioning them as a highly attractive option for future advanced energy storage systems.Challenges such as slow transformation kinetics and shuttle effects associated with lithium polysulfides(LiPSs)have seriously hindered their practical applications.In this paper,we present a new method for the synthesis of hollow carbon-sphere-supported Co monatomic catalysts(Co-N-C).This new synthesis method achieves pyrolytic coordination using a precursor rich in imide(-RC=N-)polymers.This synthesis method not only improves the adsorbability and catalytic activity of LiPS but also significantly weakens the shuttle effect and generates Co-N-C with superior conductivity,abundant hollow structures,and a high specific surface area,thus efficiently capturing and restricting the movement of LiPS intermediates.The dispersed Co monoatomic catalysts(Co SACs)were anchored to a highly conductive nitrogen-doped carbon framework and exhibited symmetric N-coordination active sites(Co-N_(4))to ensure fast redox kinetics of LiPS and Li_(2)S_(2)/Li_(2)S solid-state products.The lithium-sulfur battery with Co-N-C as the sulfur carrier showed excellent discharging capacity of 1146.6 mAh·g^(−1) at a discharge rate of 0.5 C and maintained excellent performance at a high discharge rate of 2 C.The capacity decay rate in 500 cycles was only 0.086%per cycle,reflecting excellent long-term cycle stability.This study highlights the key role of the synergistic effect between single-atom cobalt catalysts and hollow carbon spheres in enhancing the efficiency of lithium-sulfur(Li-S)batteries.It also provides valuable insights into the construction and fabrication of highly active monatomic catalysts.The catalytic conversion efficiency of lithium polysulfides is significantly enhanced when embedded in hollow carbon architectures,which serves as a critical strategy for optimizing the electrochemical behavior of next-generation Li-S batteries.
基金supported by the National Natural Science Foundation of China(No.22208374)the Excellent Youth Scientist Award Foundation of Shandong Province(No.ZR2024YQ009)+2 种基金the Distinguished Young Scholars of the National Natural Science Foundation of China(No.22322814)CNPC Innovation Found(2022DQ02-0607)the Fundamental Research Funds for the Central Universities(No.24CX07006A).
文摘Methanol steam reforming(MSR)represents a promising route for hydrogen production,leveraging the high energy density and liquid-phase storage advantages of methanol.Copper-based catalysts have become indispensable for MSR due to their cost-effectiveness,exceptional catalytic activity,and tunable selectivity.However,persistent challenges such as thermal sintering,undesirable CO byproduct formation,diminished low-temperature reactivity,and long-term catalyst deactivation limit their broad industrial deployment.This review comprehensively examines the mechanistic pathways of MSR over Cu-based catalysts,with particular focus on differentiating catalyst formulations optimized for high-temperature(>200°C)versus low-temperature(<200°C)operation.It highlights the decisive influence of Cu nanoparticle size,electronic structure,and crystal structure on catalytic performance.Cutting-edge design strategies,including multi-element engineering,innovative synthesis techniques,and deactivation mitigation,are critically evaluated to elucidate mechanistic connections between atomic-scale structure and catalytic performance enhancement.Finally,industrial applications of commercial Cu/ZnO/Al_(2)O_(3)variants and their scalability challenges are discussed,alongside prospective strategies for catalyst innovation and engineering to advance next-generation hydrogen production.
基金supported by the Australian Research Council(ARC)Projects(DP220101139,DP220101142,and LP240100542).
文摘High‐entropy amorphous catalysts(HEACs)integrate multielement synergy with structural disorder,making them promising candidates for water splitting.Their distinctive features—including flexible coordination environments,tunable electronic structures,abundant unsaturated active sites,and dynamic structural reassembly—collectively enhance electrochemical activity and durability under operating conditions.This review summarizes recent advances in HEACs for hydrogen evolution,oxygen evolution,and overall water splitting,highlighting their disorder-driven advantages over crystalline counterparts.Catalytic performance benchmarks are presented,and mechanistic insights are discussed,focusing on how multimetallic synergy,amorphization effect,and in‐situ reconstruction cooperatively regulate reaction pathways.These insights provide guidance for the rational design of next‐generation amorphous high‐entropy electrocatalysts with improved efficiency and durability.
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Developing metal-free, carbon-based catalysts to replace platinum-based catalysts for oxygen reduction reactions (ORRs) is an emerging area of research. In recent years, different carbon structures including carbon doped with IIIA-VIIA heteroatoms (C-M site-based, where M represents the doped heteroatom) and polynitrogen (PN) compounds encapsulated in carbon nanotubes (CNTs) (N N site-based) have been synthesized. Compared to metallic catalysts, these materials are highly active, stable, inexpensive, and environmentally friendly. This review discusses the development of these materials, their ORR performances and the mechanisms for how the incorpora- tion of heteroatoms enhances the ORR activity. Strategies for tailoring the structures of the carbon substrates to improve ORR performance are also discussed. Future studies in this area will need to include optimizing synthetic strategies to control the type, amount and distribution of the incorporated heteroatoms, as well as better understanding the ORR mechanisms in these catalysts.
基金supported by the National Natural Science Foundation of China(No.51878292).
文摘Large-scale CO_(2)emissions have exacerbated the greenhouse effect,reinforcing the critical need for efficient CO_(2)mitigation methods.Plasma-catalytic technology enables CO_(2)conversion under mild conditions,especially for CO_(2)methanation(the Sabatier reaction),which has attracted significant attention due to its economic benefits and the potential for safe energy transportation via existing natural gas pipelines.The development of high-performance CO_(2)methanation catalysts remains an ongoing and long-term objective,and there is a lack of adequate in-situ characterization techniques to investigate the mechanisms.This study focuses on the Ni/La_(2)O_(3)(LN)catalyst and introduces two CO_(2)activation strategies through F and Na modifications:the Ni-Ov-Ni site activation with electron transfer from Ni0 under low-power conditions and basic site activation under high-power conditions.The LN-NaF catalysts enhance CO_(2)methanation activity across the entire power range compared to LN,achieving a CO_(2)conversion of 86.3%and CH4 selectivity of 99.4%.Additionally,LN-F(h)reaches a CH4 yield 4.15 times higher than that of LN at low power.Furthermore,in-situ diffuse reflectance infrared Fourier transform(DRIFT)spectroscopy with a self-made reactor are performed under plasma-catalytic conditions to reveal the CO_(2)adsorption and conversion mechanisms,indicating that different dopants(F,Na,and NaF)exhibit promoting effects on different intermediates,resulting in variations in CO_(2)methanation activity.This study provides valuable insights for improving catalyst performance and a thorough comprehension of mechanisms in CO_(2)methanation.
基金supported by the National Natural Science Foundation of China(Nos.21675147 and 21802003)the Jilin Provincial Science and Technology Development Program(Nos.20190201242JC,20180520142JH)the China Postdoctoral Science Foundation(No.2018M631239)。
文摘Fuel cells are one of the most promising clean energy devices to substitute for fossil fuel in the future to alleviate energy crisis and environmental pollution.As the key reaction on the cathode in the fuel cells,oxygen reduction reaction(ORR)still requires efficient noble metal catalysts such as the comme rcial Pt/C to boost the reaction for its sluggish kinetics.Therefore,it is critical to design earth-abundant carbonbased catalysts with high efficiency and long-term stability to replace the noble metal-based catalysts.This review focuses on the recent progress about carbon-based ORR catalysts including non-metal doped carbon materials,transition metal-nitrogen-carbon species,transition metal carbides/carbon,single atom catalysts,and other carbon hybrids.And we further infer that the excellent ORR performances can be achieved by the balance of geometric and electronic structures of catalysts such as conductivity,surface area,hierarchical porous structure,defect and doping effect.Additionally,the perspective development trend is also proposed to guide the rational designation of carbon-based catalysts for ORR and even extend to other energy storage and conversion fields in the future.
文摘Electrocatalytic carbon dioxide(CO_(2))reduction is an important way to achieve carbon neutrality by converting CO_(2)in-to high-value-added chemicals using electric energy.Carbon-based materials are widely used in various electrochemical reactions,including electrocatalytic CO_(2)reduction,due to their low cost and high activity.In recent years,defect engineering has attracted wide attention by constructing asymmetric defect centers in the materials,which can optimize the physicochemical properties of the mater-ial and improve its electrocatalytic activity.This review summarizes the types,methods of formation and defect characterization tech-niques of defective carbon-based materials.The advantages of defect engineering and the advantages and disadvantages of various defect formation methods and characterization techniques are also evaluated.Finally,the challenges of using defective carbon-based materials in electrocatalytic CO_(2)reduction are investigated and opportunities for their use are discussed.It is believed that this re-view will provide suggestions and guidance for developing defective carbon-based materials for CO_(2)reduction.
基金financially supported by the National Natural Science Foundation of China(Grant Nos.U1710256 and U1810115)the Shanxi Science and Technology Major Project(Grant Nos.20181102019 and 20201101016)。
文摘Proton exchange membrane fuel cell(PEMFC)has important implications for the success of clean transportation in the future.One of the key factors affecting the cost and performance of PEMFC is the cathode electrocatalyst for the oxygen reduction reaction(ORR)to overcome sluggish kinetics and instability in an acidic environment.As an essential component of the electrocatalyst,the support material largely determines the activity,mass transfer,charge transfer,and durability of the electrocatalyst.Thereby,the support material plays a critical role in the overall performance of the electrocatalyst.Carbonbased materials are widely used as electrocatalyst supports because of their high porosity,conductivity,chemical stability,and tunable morphology.Recently,some new carbon-based materials with excellent structure have been introduced,such as carbon nanotubes,carbon nanowires,graphene,metal-organic framework(MOF)-derived carbon,and biomass-derived carbon materials.Combined with a variety of strategies,such as controllable construction of porous structures and surface defects,proper doping heteroatoms,the ingenious design of model electrocatalysts,and predictive theoretical calculation,a new reliable path was provided for further improving the performance of electrocatalysts and exploring the catalytic mechanism.Based on the topic of carbon-based materials for ORR in acidic medium,this review summarizes the up-to-date progress and breakthroughs,highlights the factors affecting the catalytic activity and stability of ORR electrocatalysts in acids,and discusses their future application and development.
基金supported by the National Natural Science Foundation of China(No.22379111 and 22179093).
文摘The electrochemical production of hydrogen peroxide(H_(2)O_(2))by the two-electron oxygen reduction(2e^(-)-ORR)process has the advantages of high safety,low energy consumption,and environmental friendliness.For 2e^(-)-ORR,the catalyst/electrode is the key component as it strongly affects catalytic performance and cost.Carbon materials have the advantages of high electronic conductivity,good structural stability,easy control of nanostructures,and low cost.Therefore,it has been regarded as a promising catalyst/electrode material for the electrosynthesis of H_(2)O_(2)via 2e^(-)-ORR.In addition,studies have also considered the optimization of the liquid/gas interface by tuning the electrode surface,electrolyte pH,and reactor configurations for further improving the activity and selectivity of catalysts.In this review,we provide an in-depth discussion of the recent research on the carbon-based electrocatalysts for 2e^(-)ORR,especially in terms of microenvironment tuning,catalyst/electrode interface engineering,and reactor design for achieving stable and efficient production of H_(2)O_(2).The challenges that we are still facing and the future development prospects will then be concluded,which we believe should help the future development in this field.