The electrochemical reduction of carbon dioxide offers a sound and economically viable technology for the electrification and decarbonization of the chemical and fuel industries.In this technology,an electrocatalytic ...The electrochemical reduction of carbon dioxide offers a sound and economically viable technology for the electrification and decarbonization of the chemical and fuel industries.In this technology,an electrocatalytic material and renewable energy-generated electricity drive the conversion of carbon dioxide into high-value chemicals and carbon-neutral fuels.Over the past few years,single-atom catalysts have been intensively studied as they could provide near-unity atom utilization and unique catalytic performance.Single-atom catalysts have become one of the state-of-the-art catalyst materials for the electrochemical reduction of carbon dioxide into carbon monoxide.However,it remains a challenge for single-atom catalysts to facilitate the efficient conversion of carbon dioxide into products beyond carbon monoxide.In this review,we summarize and present important findings and critical insights from studies on the electrochemical carbon dioxide reduction reaction into hydrocarbons and oxygenates using single-atom catalysts.It is hoped that this review gives a thorough recapitulation and analysis of the science behind the catalysis of carbon dioxide into more reduced products through singleatom catalysts so that it can be a guide for future research and development on catalysts with industry-ready performance for the electrochemical reduction of carbon dioxide into high-value chemicals and carbon-neutral fuels.展开更多
Developing Cu single-atom catalysts(SACs)with well-defined active sites is highly desirable for producing CH4 in the electrochemical CO_(2)reduction reaction and understanding the structure-property relationship.Herei...Developing Cu single-atom catalysts(SACs)with well-defined active sites is highly desirable for producing CH4 in the electrochemical CO_(2)reduction reaction and understanding the structure-property relationship.Herein,a new graphdiyne analogue with uniformly distributed N2-bidentate(note that N2-bidentate site=N^N-bidentate site;N2¹dinitrogen gas in this work)sites are synthesized.Due to the strong interaction between Cu and the N2-bidentate site,a Cu SAC with isolated undercoordinated Cu-N2 sites(Cu1.0/N2-GDY)is obtained,with the Cu loading of 1.0 wt%.Cu1.0/N2-GDY exhibits the highest Faradaic efficiency(FE)of 80.6%for CH4 in electrocatalytic reduction of CO_(2)at-0.96 V vs.RHE,and the partial current density of CH4 is 160 mA cm^(-2).The selectivity for CH4 is maintained above 70%when the total current density is 100 to 300 mA cm^(-2).More remarkably,the Cu1.0/N2-GDY achieves a mass activity of 53.2 A/mgCu toward CH4 under-1.18 V vs.RHE.In situ electrochemical spectroscopic studies reveal that undercoordinated Cu-N2 sites are more favorable in generating key*COOH and*CHO intermediate than Cu nanoparticle counterparts.This work provides an effective pathway to produce SACs with undercoordinated Metal-N2 sites toward efficient electrocatalysis.展开更多
Aqueous zinc-sulfur batteries at room temperature hold great potential for next-generation energy storage technology due to their low cost,safety and high energy density.However,slow reaction kinetics and high activat...Aqueous zinc-sulfur batteries at room temperature hold great potential for next-generation energy storage technology due to their low cost,safety and high energy density.However,slow reaction kinetics and high activation energy at the sulfur cathode pose great challenges for the practical applications.Herein,biomass-derived carbon with single-atomic cobalt sites(MMPC-Co)is synthesized as the cathode in Zn-S batteries.The catalysis of single-atom Co sites greatly promotes the transform of cathode electrolyte interface(CEI)on the cathode surface,while offering accelerated charge transfer rate for high conversion reversibility and large electrochemical surface area(ECSA)for high electrocatalytic current.Furthermore,the rich pore structure not only physically limits sulfur loss,but also accelerates the transport of zinc ions.In addition,the large pore volume of MMPC-Co is able to relieve the stress effect caused by the volume expansion of Zn S during charge/discharge cycles,thereby maintaining the stability of electrode structure.Consequently,the sulfur cathode maintains a high specific capacity of 729.96 m A h g^(-1)after 500 cycles at4 A g^(-1),which is much better than most cathode materials reported in the literature.This work provides new insights into the design and development of room-temperature aqueous Zn-S batteries.展开更多
Metal halide perovskite(MHP)has become one of the most promising materials for photocatalytic CO_(2)reduction owing to the wide light absorption range,negative conduction band position and high reduction ability.Howev...Metal halide perovskite(MHP)has become one of the most promising materials for photocatalytic CO_(2)reduction owing to the wide light absorption range,negative conduction band position and high reduction ability.However,photoreduction of CO_(2)by MHP remains a challenge because of the slow charge separation and transfer.Herein,a cobalt single-atom modified nitrogen-doped graphene(Co-NG)cocatalyst is prepared for enhanced photocatalytic CO_(2)reduction of bismuth-based MHP Cs_(3)Bi_(2)Br_(9).The optimal Cs_(3)Bi_(2)Br_(9)/Co-NG composite exhibits the CO production rate of 123.16μmol g-1 h-1,which is 17.3 times higher than that of Cs_(3)Bi_(2)Br_(9).Moreover,the Cs_(3)Bi_(2)Br_(9)/Co-NG composite photocatalyst exhibits nearly 100%CO selectivity as well as impressive long-term stability.Charge carrier dynamic characterizations such as Kelvin probe force microscopy(KPFM),single-particle PL microscope and transient absorption(TA)spectroscopy demonstrate the vital role of Co-NG cocatalyst in accelerating the transfer and separation of photogenerated charges and improving photocatalytic performance.The reaction mechanism has been demonstrated by in situ diffuse reflectance infrared Fourier-transform spectroscopy measurement.In addition,in situ X-ray photoelectron spectroscopy test and theoretical calculation reveal the reaction reactive sites and reaction energy barriers,demonstrating that the introduction of Co-NG promotes the formation of~(*)COOH intermediate,providing sufficient evidence for the highly selective generation of CO.This work provides an effective single-atom-based cocatalyst modification strategy for photocatalytic CO_(2)reduction and is expected to shed light on other photocatalytic applications.展开更多
Lithium-sulfur(Li-S) batteries have attracted considerable attention as one of the most appealing energy storage systems.Strenuous efforts have been devoted to tackling the tremendous challenges,mainly pertaining to t...Lithium-sulfur(Li-S) batteries have attracted considerable attention as one of the most appealing energy storage systems.Strenuous efforts have been devoted to tackling the tremendous challenges,mainly pertaining to the severe shuttle effect,sluggish redox kinetics and lithium dendritic growth.Single-atomic mediators as promising candidates exhibit impressive performance in addressing these intractable issues.Related research often utilizes a trial-and-error approach,proposing solutions to fabricate single-atomic materials with diversified features.However,comprehensive review articles especially targeting demand-driven preparation are still in a nascent stage.Inspired by these considerations,this review summarizes the design of single-atomic mediators based on the application case-studies in LiS batteries and other metal-sulfur systems.Emerging preparation routes represented by chemical vapor deposition technology are introduced in a demand-oriented classification.Finally,future research directions are proposed to foster the advancement of single-atomic mediators in Li-S realm.展开更多
The electronic configuration of central metal atoms in single-atom catalysts(SACs)is pivotal in electrochemical CO_(2)reduction reaction(eCO_(2)RR).Herein,chalcogen heteroatoms(e.g.,S,Se,and Te)were incorporated into ...The electronic configuration of central metal atoms in single-atom catalysts(SACs)is pivotal in electrochemical CO_(2)reduction reaction(eCO_(2)RR).Herein,chalcogen heteroatoms(e.g.,S,Se,and Te)were incorporated into the symmetric nickel-nitrogen-carbon(Ni-N4-C)configuration to obtain Ni-X-N3-C(X:S,Se,and Te)SACs with asymmetric coordination presented for central Ni atoms.Among these obtained Ni-X-N3-C(X:S,Se,and Te)SACs,Ni-Se-N3-C exhibited superior eCO_(2)RR activity,with CO selectivity reaching~98%at-0.70 V versus reversible hydrogen electrode(RHE).The Zn-CO_(2)battery integrated with Ni-Se-N3-C as cathode and Zn foil as anode achieved a peak power density of 1.82 mW cm-2 and maintained remarkable rechargeable stability over 20 h.In-situ spectral investigations and theoretical calculations demonstrated that the chalcogen heteroatoms doped into the Ni-N4-C configuration would break coordination symmetry and trigger charge redistribution,and then regulate the intermediate behaviors and thermodynamic reaction pathways for eCO_(2)RR.Especially,for Ni-Se-N3-C,the introduced Se atoms could significantly raise the d-band center of central Ni atoms and thus remarkably lower the energy barrier for the rate-determining step of*COOH formation,contributing to the promising eCO_(2)RR performance for high selectivity CO production by competing with hydrogen evolution reaction.展开更多
Precision engineering of catalytic sites to guide more favorable pathways for Li_(2)O_(2) nucleation and decom-position represents an enticing kinetic strategy for mitigating overpotential,enhancing discharge capac-it...Precision engineering of catalytic sites to guide more favorable pathways for Li_(2)O_(2) nucleation and decom-position represents an enticing kinetic strategy for mitigating overpotential,enhancing discharge capac-ity,and improving recycling stability of Li-O_(2) batteries.In this work,we employ metal-organic frameworks(MOFs)derivation and ion substitution strategies to construct atomically dispersed Mn-N_(4) moieties on hierarchical porous nitrogen-doped carbon(Mn SAs-NC)with the aim of reducing the over-potential and improving the cycling stability of Li-O_(2) batteries.The porous structure provides more chan-nels for mass transfer and exposes more highly active sites for electrocatalytic reactions,thus promoting the formation and decomposition of Li_(2)O_(2).The Li-O_(2) batteries with Mn SAs-NC cathode achieve lower overpotential,higher specific capacity(14290 mA h g^(-1) at 100 mAg^(-1)),and superior cycle stability(>100 cycles at 200 mA g^(-1))compared with the Mn NPs-NC and NC.Density functional theory(DFT)cal-culations reveal that the construction of Mn-N_(4) moiety tunes the charge distribution of the pyridinic N-rich vacancy and balances the affinity of the intermediates(LiO_(2) and Li_(2)O_(2)).The initial nucleation of Li_(2)O_(2) on Mn SAs-NC favors the O_(2)-→LiO_(2)→Li_(2)O_(2) surface-adsorption pathway,which mitigates the overpoten-tials of the oxygen reduction(ORR)and oxygen evolution reaction(OER).As a result,Mn SAs-NC with Mn-N_(4) moiety effectively facilitates the Li_(2)O_(2) nucleation and enables its reversible decomposition.This work establishes a methodology for constructing carbon-based electrocatalysts with high activity and selectivity for Li-O_(2)batteries.展开更多
Anodic urea oxidation reaction(UOR)is an intriguing half reaction that can replace oxygen evolution reaction(OER)and work together with hydrogen evolution reaction(HER)toward simultaneous hydrogen fuel generation and ...Anodic urea oxidation reaction(UOR)is an intriguing half reaction that can replace oxygen evolution reaction(OER)and work together with hydrogen evolution reaction(HER)toward simultaneous hydrogen fuel generation and urea-rich wastewater purification;however,it remains a challenge to achieve overall urea electrolysis with high efficiency.Herein,we report a multifunctional electrocatalyst termed as Rh/Ni V-LDH,through integration of nickel-vanadium layered double hydroxide(LDH)with rhodium single-atom catalyst(SAC),to achieve this goal.The electrocatalyst delivers high HER mass activity of0.262 A mg^(-1) and exceptionally high turnover frequency(TOF)of 2.125 s^(-1) at an overpotential of100 m V.Moreover,exceptional activity toward urea oxidation is addressed,which requires a potential of 1.33 V to yield 10 mA cm^(-2),endorsing the potential to surmount the sluggish OER.The splendid catalytic activity is enabled by the synergy of the Ni V-LDH support and the atomically dispersed Rh sites(located on the Ni-V hollow sites)as evidenced both experimentally and theoretically.The selfsupported Rh/Ni V-LDH catalyst serving as the anode and cathode for overall urea electrolysis(1 mol L^(-1) KOH with 0.33 mol L^(-1) urea as electrolyte)only requires a small voltage of 1.47 V to deliver 100 mA cm^(-2) with excellent stability.This work provides important insights into multifunctional SAC design from the perspective of support sites toward overall electrolysis applications.展开更多
Lithium-sulfur batteries(LSBs)have been regarded as one of the promising candidates for the next-generation“lithium-ion battery beyond”owing to their high energy density and due to the low cost of sulfur.However,the...Lithium-sulfur batteries(LSBs)have been regarded as one of the promising candidates for the next-generation“lithium-ion battery beyond”owing to their high energy density and due to the low cost of sulfur.However,the main obstacles encountered in the commercial implementation of LSBs are the notorious shuttle effect,retarded sulfur redox kinetics,and uncontrolled dendrite growth.Accordingly,single-atom catalysts(SACs),which have ultrahigh catalytic efficiency,tunable coordination configuration,and light weight,have shown huge potential in the field of LSBs to date.This review summarizes the recent research progress of SACs applied as multifunctional components in LSBs.The design principles and typical synthetic strategies of SACs toward effective Li–S chemistry as well as the working mechanism promoting sulfur conversion reactions,inhibiting the lithium polysulfide shuttle effect,and regulating Li+nucleation are comprehensively illustrated.Potential future directions in terms of research on SACs for the realization of commercially viable LSBs are also outlined.展开更多
The development of novel single-atom catalysts with optimal electron configuration and economical noble-metal cocatalyst for efficient photocatalytic hydrogen production is of great importance,but still challenging.He...The development of novel single-atom catalysts with optimal electron configuration and economical noble-metal cocatalyst for efficient photocatalytic hydrogen production is of great importance,but still challenging.Herein,we fabricate Pt and Co single-atom sites successively on polymeric carbon nitride(CN).In this Pt_(1)-Co_(1)/CN bimetallic single-atom catalyst,the noble-metal active sites are maximized,and the single-atomic Co_(1)N_4sites are tuned to Co_(1)N_3sites by photogenerated electrons arising from the introduced single-atomic Pt_(1)N_4sites.Mechanism studies and density functional theory(DFT)calculations reveal that the 3d orbitals of Co_(1)N_3single sites are filled with unpaired d-electrons,which lead to the improved visible-light response,carrier separation and charge migration for CN photocatalysts.Thereafter,the protons adsorption and activation are promoted.Taking this advantage of long-range electron synergy in bimetallic single atomic sites,the photocatalytic hydrogen evolution activity over Pt_(1)-Co_(1)/CN achieves 915.8 mmol g^(-1)Pt h^(-1),which is 19.8 times higher than Co_(1)/CN and 3.5 times higher to Pt_(1)/CN.While this electron-synergistic effect is not so efficient for Pt nanoclusters.These results demonstrate the synergistic effect at electron-level and provide electron-level guidance for the design of efficient photocatalysts.展开更多
The practical application of lithium–sulfur batteries(LSBs)is severely hindered by the undesirable shuttling of lithium polysulfides(LiPSs)and sluggish redox kinetics of sulfur species.Herein,a series of ultrathin si...The practical application of lithium–sulfur batteries(LSBs)is severely hindered by the undesirable shuttling of lithium polysulfides(LiPSs)and sluggish redox kinetics of sulfur species.Herein,a series of ultrathin singleatomic tungsten-doped Co_(3)O_(4)(Wx-Co_(3)O_(4))nanosheets as catalytic additives in the sulfur cathode for LSBs are rationally designed and synthesized.Benefiting from the enhanced catalytic activity and optimized electronic structure by W doping,the Wx-Co_(3)O_(4) not only reduces the shuttling of LiPSs but also decreases the energy barrier of sulfur redox reactions of sulfur species,leading to accelerated electrode kinetic.As a result,LSB cathodes with the use of 5.0 wt%W0.02-Co_(3)O_(4) as the electrocatalyst show the high reversible capacities of 1217.0 and 558.6 mAh g^(-1) at 0.2 and 5.0 C,respectively,and maintain a high reversible capacity of 644.6 mAh g^(-1) at 1.0 C(1.0 C=1675 mA g^(-1))after 500 cycles.With a high sulfur loading of 5.5 mg cm^(-2) and electrolyte–electrode ratio of 8μL_(electrolyte) mg_(sulfur)^(-1),the 5.0 wt%W_(0.02)-Co_(3)O_(4)-based sulfur cathode also retains a high reversible areal capacity of 3.86 mAh cm^(-2) at 0.1 C after 50 cycles with an initial capacity retention of 84.7%.展开更多
A fuel cell is an energy conversion device that can continuously input fuel and oxidant into the device through an electrochemical reaction to release electrical energy.Although noble metals show good activity in fuel...A fuel cell is an energy conversion device that can continuously input fuel and oxidant into the device through an electrochemical reaction to release electrical energy.Although noble metals show good activity in fuel cell-related electrochemical reactions,their ever-increasing price considerably hinders their industrial application.Improvement of atom utilization efficiency is considered one of the most effective strategies to improve the mass activity of catalysts,and this allows for the use of fewer catalysts,saving greatly on the cost.Thus,single-atom catalysts(SACs)with an atom utilization efficiency of 100%have been widely developed,which show remarkable performance in fuel cells.In this review,we will describe recent progress on the development of SACs for membrane electrode assembly of fuel cell applications.First,we will introduce several effective routes for the synthesis of SACs.The reaction mechanism of the involved reactions will also be introduced as it is highly determinant of the final activity.Then,we will systematically summarize the application of Pt group metal(PGM)and nonprecious group metal(non-PGM)catalysts in membrane electrode assembly of fuel cells.This review will offer numerous experiences for developing potential industrialized fuel cell catalysts in the future.展开更多
As a zero-carbon fuel,hydrogen can be produced via electrochemical water splitting using clean electric energy by the hydrogen evolution reaction(HER)process.The ultimate goal of HER catalyst is to replace the expensi...As a zero-carbon fuel,hydrogen can be produced via electrochemical water splitting using clean electric energy by the hydrogen evolution reaction(HER)process.The ultimate goal of HER catalyst is to replace the expensive Pt metal benchmark with a cheap one with equivalent activities.In this work,we investigated the possibility of HER process on single-atom catalysts(SACs)doped on two-dimensional(2D)GaPS_(4)materials,which have a large intrinsic band gap that can be regulated by doping and tensile strain.Based on the machine learning regression analysis,we can expand the prediction of HER performance to more catalysts without expensive DFT calculation.The electron affinity and first ionization energy are the two most important descriptors related to the HER behavior.Furthermore,constrain molecular dynamics with solvation models and constant potentials were applied to understand the dynamics barrier of HER process of Pt SAC on GaPS_(4)materials.These findings not only provide important insights into the catalytic properties of single-atom catalysts on GaPS_(4)2D materials,but also provides theoretical guidance paradigm for exploration of new catalysts.展开更多
Various strategies,including controls of morphology,oxidation state,defect,and doping,have been developed to improve the performance of Cu-based catalysts for CO_(2) reduction reaction(CO_(2)RR),generating a large amo...Various strategies,including controls of morphology,oxidation state,defect,and doping,have been developed to improve the performance of Cu-based catalysts for CO_(2) reduction reaction(CO_(2)RR),generating a large amount of data.However,a unified understanding of underlying mechanism for further optimization is still lacking.In this work,combining first-principles calculations and machine learning(ML)techniques,we elucidate critical factors influencing the catalytic properties,taking Cu-based single atom alloys(SAAs)as examples.Our method relies on high-throughput calculations of 2669 CO adsorption configurations on 43 types of Cu-based SAAs with various surfaces.Extensive ML analyses reveal that low generalized coordination numbers and valence electron number are key features to determine catalytic performance.Applying our ML model with cross-group learning scheme,we demonstrate the model generalizes well between Cu-based SAAs with different alloying elements.Further,electronic structure calculations suggest surface negative center could enhance CO adsorption by back donating electrons to antibonding orbitals of CO.Finally,several SAAs,including PCu,AgCu,GaCu,ZnCu,SnCu,GeCu,InCu,and SiCu,are identified as promising CO_(2)RR catalysts.Our work provides a paradigm for the rational design and fast screening of SAAs for various electrocatalytic reactions.展开更多
Electrochemical carbon dioxide reduction reaction(CO_(2)RR)provides an attractive approach to carbon capture and utilization for the production high-value-added products.However,CO_(2)RR still suffers from poor select...Electrochemical carbon dioxide reduction reaction(CO_(2)RR)provides an attractive approach to carbon capture and utilization for the production high-value-added products.However,CO_(2)RR still suffers from poor selectivity and low current density due to its sluggish kinetics and multitudinous reaction pathways.Single-atom catalysts(SACs)demonstrate outstanding activity,excellent selectivity,and remarkable atom utilization efficiency,which give impetus to the search for electrocatalytic processes aiming at high selectivity.There appears significant activity in the development of efficient SACs for CO_(2)RR,while the density of the atomic sites remains a considerable barrier to be overcome.To construct high-metal-loading SACs,aggregation must be prevented,and thus novel strategies are required.The key to creating high-density atomically dispersed sites is designing enough anchoring sites,normally defects,to stabilize the highly mobile separated metal atoms.In this review,we summarized the advances in developing high-loading SACs through defect engineering,with a focus on the synthesis strategies to achieve high atomic site loading.Finally,the future opportunities and challenges for CO_(2)RR in the area of high-loading single-atom electrocatalysts are also discussed.展开更多
The stimuli-responsive anticorrosion coatings have drawn great attention as a prospective corrosion protection approach due to their smart self-repairing properties.In contrast to passive protection mechanism based on...The stimuli-responsive anticorrosion coatings have drawn great attention as a prospective corrosion protection approach due to their smart self-repairing properties.In contrast to passive protection mechanism based on post-corrosion microenvironmental changes,a unique active protection strategy based on nanocatalytic oxygen depletion is proposed in this work to inhibit the occurrence of corrosion.Porous FeeNeC catalysts with outstanding oxygen reduction reaction(ORR)activity(half-wave potential of 0.89 V)is firstly synthesized through pre-coordination with organosilane precursor to obtain homogeneously distributed active sites.When this catalyst is introduced into the coating matrix,uniformly distributed FeeNeC not only compensates the defects but plays a crucial role in adsorption and consumption of diffused oxygen in the coating.Under this dual action,the penetration of corrosive medium,especially oxygen,through coating to metal substrate is greatly suppressed,resulting in effective corrosion inhibition and a significant increase in corrosion resistance of the composite coating compared to pure epoxy coating.This work provides a new perspective and the starting point for the design of high-performance smart coating with active anticorrosion properties.展开更多
The next-generation energy storage systems such as fuel cells,metal-air batteries,and alkali metal(Li,Na)-chalcogen(S,Se)batteries have received increasing attention owing to their high energy density and low cost.How...The next-generation energy storage systems such as fuel cells,metal-air batteries,and alkali metal(Li,Na)-chalcogen(S,Se)batteries have received increasing attention owing to their high energy density and low cost.However,one of the main obstacles of these systems is the poor reaction kinetics in the involved chemical reactions.Therefore,it is essential to incorporate suitable and efficient catalysts into the cell.These years,single-atom catalysts(SACs)are emerging as a frontier in catalysis due to their maximum atom efficiency and unique reaction selectivity.For SACs fabrication,metal-organic frameworks(MOFs)have been confirmed as promising templates or precursors due to their high metal loadings,structural adjustability,porosity,and tailorable catalytic site.In this review,we summarize effective strategies for fabricating SACs by MOFs with corresponding advanced characterization techniques and illustrate the key role of MOFs-based SACs in these batteries by explaining their reaction mechanisms and challenges.Finally,current applications,prospects,and opportunities for MOFs-based SACs in energy storage systems are discussed.展开更多
The demand for clean and sustainable energy has encouraged the production of hydrogen from water electrolyzers.To overcome the obstacle to improving the efficiency of water electrolyzers,it is highly desired to fabric...The demand for clean and sustainable energy has encouraged the production of hydrogen from water electrolyzers.To overcome the obstacle to improving the efficiency of water electrolyzers,it is highly desired to fabricate active electrocatalysts for the sluggish oxygen evolution process.However,there is generally an intrinsic gap between the as-prepared and real electrocatalysts due to structure evolution under the oxidative reaction conditions.Here,we combine in-situ anionic leaching and atomic deposition to realize single-atom catalysts with self-optimized structures.The introduced F ions facilitate structural transformation from Co(OH)xF into CoOOH(F),which generates an amorphous edge surface to provide more anchoring sites for Ir single atoms.Meanwhile,the in-situ anionic leaching of F ions elevates the Co valence state of Ir_(1)/CoOOH(F)more significantly than the counterpart without F ions(Ir_(1)/CoOOH),leading to stronger adsorption of oxygenated intermediates.As revealed by electrochemical measurements,the increased Ir loading together with the favored adsorption of*OH intermediates improve the catalytic activity of Ir_(1)/CoOOH(F).Specifically,Ir_(1)/CoOOH(F)delivered a current density of 10 mA cm-2at an overpotential of 238 mV,being lower than 314 mV for Ir_(1)/CoOOH.The results demonstrated the facility of the in-situ optimization process to optimize catalyst structure for improved performance.展开更多
In this work,DFT calculations were used firstly to simulate the nitrogen coordinated metal single-atom catalysts(M-N_(x)SACs,M=Hg,Cu,Au,and Ru) to predict their catalytic activities in acetylene hydrochlorination.The ...In this work,DFT calculations were used firstly to simulate the nitrogen coordinated metal single-atom catalysts(M-N_(x)SACs,M=Hg,Cu,Au,and Ru) to predict their catalytic activities in acetylene hydrochlorination.The DFT results showed that Ru-N_(x)SACs had the best catalytic performance among the four catalysts,and Ru-N_(x)SACs could effectively inhibit the reduction of ruthenium cation.To verify the DFT results,Ru-N_(x)SACs were fabricated by pyrolyzing MOFs in-situ spatially confined metal precursors.The N coordination environment could be controlled by changing the pyrolysis temperature.Catalytic performance tests indicated that low N coordination number(Ru-N_(2),Ru-N_(3))exhibited excellent catalytic activity and stability compared to RuCl_(3)catalyst.DFT calculations further revealed that Ru-N_(2)and Ru-N_(3)had a tendency to activate HCl at the first step of reaction,whereas Ru-N4tended to activate C_(2)H_(2).These findings will serve as a reference for the design and control of metal active sites.展开更多
Developing efficient electrocatalysts for converting dinitrogen to ammonia through electrocatalysis is of significance to the decentralized ammonia production. Here, through high-throughput density functional theory c...Developing efficient electrocatalysts for converting dinitrogen to ammonia through electrocatalysis is of significance to the decentralized ammonia production. Here, through high-throughput density functional theory calculations, we demonstrated that the interfacial modulation of hexagonal boron nitride/graphene(hBN-graphene) could sufficiently improve the catalytic activity of the single transition metal atom catalysts for nitrogen reduction reaction(NRR). It was revealed that Re@hBN-graphene and Os@hBN-graphene possessed remarkable NRR catalytic activity with low limiting potentials of 0.29 V and 0.33 V, respectively. Furthermore, the mechanism of the enhanced catalytic activity was investigated based on various descriptors of the adsorption energies of intermediates, where the synergistic effect of hBN and graphene in the hybrid substrate was found to play a key role. Motivated by the synergistic effect of hybrid substrate in single-atom catalysts, a novel strategy was proposed to efficiently design dual-atom catalysts by integrating the merits of both metal components. The as-designed dual-atom catalyst Fe-Mo@hBN exhibited more excellent NRR catalytic performance with a limiting potential of 0.17 V, manifesting the solidity of the design strategy. Our findings open new avenues for the search of heterostructure substrates for single-atom catalysts and the efficient design of dualatom catalysts for NRR.展开更多
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korean government(MSIP)(NRF,2021R1C1C1013953,2022K1A4A7A04094394,2022K1A4A7A04095890)。
文摘The electrochemical reduction of carbon dioxide offers a sound and economically viable technology for the electrification and decarbonization of the chemical and fuel industries.In this technology,an electrocatalytic material and renewable energy-generated electricity drive the conversion of carbon dioxide into high-value chemicals and carbon-neutral fuels.Over the past few years,single-atom catalysts have been intensively studied as they could provide near-unity atom utilization and unique catalytic performance.Single-atom catalysts have become one of the state-of-the-art catalyst materials for the electrochemical reduction of carbon dioxide into carbon monoxide.However,it remains a challenge for single-atom catalysts to facilitate the efficient conversion of carbon dioxide into products beyond carbon monoxide.In this review,we summarize and present important findings and critical insights from studies on the electrochemical carbon dioxide reduction reaction into hydrocarbons and oxygenates using single-atom catalysts.It is hoped that this review gives a thorough recapitulation and analysis of the science behind the catalysis of carbon dioxide into more reduced products through singleatom catalysts so that it can be a guide for future research and development on catalysts with industry-ready performance for the electrochemical reduction of carbon dioxide into high-value chemicals and carbon-neutral fuels.
文摘Developing Cu single-atom catalysts(SACs)with well-defined active sites is highly desirable for producing CH4 in the electrochemical CO_(2)reduction reaction and understanding the structure-property relationship.Herein,a new graphdiyne analogue with uniformly distributed N2-bidentate(note that N2-bidentate site=N^N-bidentate site;N2¹dinitrogen gas in this work)sites are synthesized.Due to the strong interaction between Cu and the N2-bidentate site,a Cu SAC with isolated undercoordinated Cu-N2 sites(Cu1.0/N2-GDY)is obtained,with the Cu loading of 1.0 wt%.Cu1.0/N2-GDY exhibits the highest Faradaic efficiency(FE)of 80.6%for CH4 in electrocatalytic reduction of CO_(2)at-0.96 V vs.RHE,and the partial current density of CH4 is 160 mA cm^(-2).The selectivity for CH4 is maintained above 70%when the total current density is 100 to 300 mA cm^(-2).More remarkably,the Cu1.0/N2-GDY achieves a mass activity of 53.2 A/mgCu toward CH4 under-1.18 V vs.RHE.In situ electrochemical spectroscopic studies reveal that undercoordinated Cu-N2 sites are more favorable in generating key*COOH and*CHO intermediate than Cu nanoparticle counterparts.This work provides an effective pathway to produce SACs with undercoordinated Metal-N2 sites toward efficient electrocatalysis.
基金the financial support from the National Natural Science Foundation of China,China(No.52172058)。
文摘Aqueous zinc-sulfur batteries at room temperature hold great potential for next-generation energy storage technology due to their low cost,safety and high energy density.However,slow reaction kinetics and high activation energy at the sulfur cathode pose great challenges for the practical applications.Herein,biomass-derived carbon with single-atomic cobalt sites(MMPC-Co)is synthesized as the cathode in Zn-S batteries.The catalysis of single-atom Co sites greatly promotes the transform of cathode electrolyte interface(CEI)on the cathode surface,while offering accelerated charge transfer rate for high conversion reversibility and large electrochemical surface area(ECSA)for high electrocatalytic current.Furthermore,the rich pore structure not only physically limits sulfur loss,but also accelerates the transport of zinc ions.In addition,the large pore volume of MMPC-Co is able to relieve the stress effect caused by the volume expansion of Zn S during charge/discharge cycles,thereby maintaining the stability of electrode structure.Consequently,the sulfur cathode maintains a high specific capacity of 729.96 m A h g^(-1)after 500 cycles at4 A g^(-1),which is much better than most cathode materials reported in the literature.This work provides new insights into the design and development of room-temperature aqueous Zn-S batteries.
文摘Metal halide perovskite(MHP)has become one of the most promising materials for photocatalytic CO_(2)reduction owing to the wide light absorption range,negative conduction band position and high reduction ability.However,photoreduction of CO_(2)by MHP remains a challenge because of the slow charge separation and transfer.Herein,a cobalt single-atom modified nitrogen-doped graphene(Co-NG)cocatalyst is prepared for enhanced photocatalytic CO_(2)reduction of bismuth-based MHP Cs_(3)Bi_(2)Br_(9).The optimal Cs_(3)Bi_(2)Br_(9)/Co-NG composite exhibits the CO production rate of 123.16μmol g-1 h-1,which is 17.3 times higher than that of Cs_(3)Bi_(2)Br_(9).Moreover,the Cs_(3)Bi_(2)Br_(9)/Co-NG composite photocatalyst exhibits nearly 100%CO selectivity as well as impressive long-term stability.Charge carrier dynamic characterizations such as Kelvin probe force microscopy(KPFM),single-particle PL microscope and transient absorption(TA)spectroscopy demonstrate the vital role of Co-NG cocatalyst in accelerating the transfer and separation of photogenerated charges and improving photocatalytic performance.The reaction mechanism has been demonstrated by in situ diffuse reflectance infrared Fourier-transform spectroscopy measurement.In addition,in situ X-ray photoelectron spectroscopy test and theoretical calculation reveal the reaction reactive sites and reaction energy barriers,demonstrating that the introduction of Co-NG promotes the formation of~(*)COOH intermediate,providing sufficient evidence for the highly selective generation of CO.This work provides an effective single-atom-based cocatalyst modification strategy for photocatalytic CO_(2)reduction and is expected to shed light on other photocatalytic applications.
基金supported by the National Natural Science Foundation of China(22179089)the Postgraduate Research&Practice Innovation Program of Jiangsu Province(KYCX23_3245)support from Suzhou Key Laboratory for Advanced Carbon Materials and Wearable Energy Technologies,Suzhou,China。
文摘Lithium-sulfur(Li-S) batteries have attracted considerable attention as one of the most appealing energy storage systems.Strenuous efforts have been devoted to tackling the tremendous challenges,mainly pertaining to the severe shuttle effect,sluggish redox kinetics and lithium dendritic growth.Single-atomic mediators as promising candidates exhibit impressive performance in addressing these intractable issues.Related research often utilizes a trial-and-error approach,proposing solutions to fabricate single-atomic materials with diversified features.However,comprehensive review articles especially targeting demand-driven preparation are still in a nascent stage.Inspired by these considerations,this review summarizes the design of single-atomic mediators based on the application case-studies in LiS batteries and other metal-sulfur systems.Emerging preparation routes represented by chemical vapor deposition technology are introduced in a demand-oriented classification.Finally,future research directions are proposed to foster the advancement of single-atomic mediators in Li-S realm.
文摘The electronic configuration of central metal atoms in single-atom catalysts(SACs)is pivotal in electrochemical CO_(2)reduction reaction(eCO_(2)RR).Herein,chalcogen heteroatoms(e.g.,S,Se,and Te)were incorporated into the symmetric nickel-nitrogen-carbon(Ni-N4-C)configuration to obtain Ni-X-N3-C(X:S,Se,and Te)SACs with asymmetric coordination presented for central Ni atoms.Among these obtained Ni-X-N3-C(X:S,Se,and Te)SACs,Ni-Se-N3-C exhibited superior eCO_(2)RR activity,with CO selectivity reaching~98%at-0.70 V versus reversible hydrogen electrode(RHE).The Zn-CO_(2)battery integrated with Ni-Se-N3-C as cathode and Zn foil as anode achieved a peak power density of 1.82 mW cm-2 and maintained remarkable rechargeable stability over 20 h.In-situ spectral investigations and theoretical calculations demonstrated that the chalcogen heteroatoms doped into the Ni-N4-C configuration would break coordination symmetry and trigger charge redistribution,and then regulate the intermediate behaviors and thermodynamic reaction pathways for eCO_(2)RR.Especially,for Ni-Se-N3-C,the introduced Se atoms could significantly raise the d-band center of central Ni atoms and thus remarkably lower the energy barrier for the rate-determining step of*COOH formation,contributing to the promising eCO_(2)RR performance for high selectivity CO production by competing with hydrogen evolution reaction.
基金supported by the National Natural Science Foundation of China (21878340)supported in part by the High-Performance Computing Center of Central South University
文摘Precision engineering of catalytic sites to guide more favorable pathways for Li_(2)O_(2) nucleation and decom-position represents an enticing kinetic strategy for mitigating overpotential,enhancing discharge capac-ity,and improving recycling stability of Li-O_(2) batteries.In this work,we employ metal-organic frameworks(MOFs)derivation and ion substitution strategies to construct atomically dispersed Mn-N_(4) moieties on hierarchical porous nitrogen-doped carbon(Mn SAs-NC)with the aim of reducing the over-potential and improving the cycling stability of Li-O_(2) batteries.The porous structure provides more chan-nels for mass transfer and exposes more highly active sites for electrocatalytic reactions,thus promoting the formation and decomposition of Li_(2)O_(2).The Li-O_(2) batteries with Mn SAs-NC cathode achieve lower overpotential,higher specific capacity(14290 mA h g^(-1) at 100 mAg^(-1)),and superior cycle stability(>100 cycles at 200 mA g^(-1))compared with the Mn NPs-NC and NC.Density functional theory(DFT)cal-culations reveal that the construction of Mn-N_(4) moiety tunes the charge distribution of the pyridinic N-rich vacancy and balances the affinity of the intermediates(LiO_(2) and Li_(2)O_(2)).The initial nucleation of Li_(2)O_(2) on Mn SAs-NC favors the O_(2)-→LiO_(2)→Li_(2)O_(2) surface-adsorption pathway,which mitigates the overpoten-tials of the oxygen reduction(ORR)and oxygen evolution reaction(OER).As a result,Mn SAs-NC with Mn-N_(4) moiety effectively facilitates the Li_(2)O_(2) nucleation and enables its reversible decomposition.This work establishes a methodology for constructing carbon-based electrocatalysts with high activity and selectivity for Li-O_(2)batteries.
基金finically supported by the National Key R&D Program of China(2017YFE0120500)the National Natural Science Foundation of China(51972129,51702150,and 21725102)+2 种基金the Key Research and Development Program of Hubei(2020BAB079)Bintuan Science and Technology Program(2020DB002,and 2022DB009)the Science and Technology Innovation Committee Foundation of Shenzhen(JCYJ20210324141613032 and JCYJ20190809142019365)。
文摘Anodic urea oxidation reaction(UOR)is an intriguing half reaction that can replace oxygen evolution reaction(OER)and work together with hydrogen evolution reaction(HER)toward simultaneous hydrogen fuel generation and urea-rich wastewater purification;however,it remains a challenge to achieve overall urea electrolysis with high efficiency.Herein,we report a multifunctional electrocatalyst termed as Rh/Ni V-LDH,through integration of nickel-vanadium layered double hydroxide(LDH)with rhodium single-atom catalyst(SAC),to achieve this goal.The electrocatalyst delivers high HER mass activity of0.262 A mg^(-1) and exceptionally high turnover frequency(TOF)of 2.125 s^(-1) at an overpotential of100 m V.Moreover,exceptional activity toward urea oxidation is addressed,which requires a potential of 1.33 V to yield 10 mA cm^(-2),endorsing the potential to surmount the sluggish OER.The splendid catalytic activity is enabled by the synergy of the Ni V-LDH support and the atomically dispersed Rh sites(located on the Ni-V hollow sites)as evidenced both experimentally and theoretically.The selfsupported Rh/Ni V-LDH catalyst serving as the anode and cathode for overall urea electrolysis(1 mol L^(-1) KOH with 0.33 mol L^(-1) urea as electrolyte)only requires a small voltage of 1.47 V to deliver 100 mA cm^(-2) with excellent stability.This work provides important insights into multifunctional SAC design from the perspective of support sites toward overall electrolysis applications.
基金Science and Technology Innovation Program of Hunan Province,Grant/Award Number:2021RC3021Project of State Key Laboratory of Environment‐Friendly Energy Materials,Grant/Award Numbers:18ZD320304,21fksy24+2 种基金Natural Science Foundation of Hunan Province,Grant/Award Number:2021JJ40780National Natural Science Foundation of China,Grant/Award Numbers:51902346,52172239Start‐up Funding of Yangtze Region Institute(Huzhou),University of Electronic Science and Technology,Grant/Award Number:U03220102。
文摘Lithium-sulfur batteries(LSBs)have been regarded as one of the promising candidates for the next-generation“lithium-ion battery beyond”owing to their high energy density and due to the low cost of sulfur.However,the main obstacles encountered in the commercial implementation of LSBs are the notorious shuttle effect,retarded sulfur redox kinetics,and uncontrolled dendrite growth.Accordingly,single-atom catalysts(SACs),which have ultrahigh catalytic efficiency,tunable coordination configuration,and light weight,have shown huge potential in the field of LSBs to date.This review summarizes the recent research progress of SACs applied as multifunctional components in LSBs.The design principles and typical synthetic strategies of SACs toward effective Li–S chemistry as well as the working mechanism promoting sulfur conversion reactions,inhibiting the lithium polysulfide shuttle effect,and regulating Li+nucleation are comprehensively illustrated.Potential future directions in terms of research on SACs for the realization of commercially viable LSBs are also outlined.
基金the support of the National Natural Science Foundation of China (22002118,22208262,52271228,52202298,52201279,51834009,51801151)the Natural Science Foundation of Shaanxi Province (2021JQ-468,2020JZ-47)+2 种基金the Natural Science Foundation of Shaanxi Provincial Department of Education (21JP086)the Postdoctoral Research Foundation of China (2020 M683528,2020TQ0245,2018M633643XB)the Hundred Talent Program of Shaanxi Province。
文摘The development of novel single-atom catalysts with optimal electron configuration and economical noble-metal cocatalyst for efficient photocatalytic hydrogen production is of great importance,but still challenging.Herein,we fabricate Pt and Co single-atom sites successively on polymeric carbon nitride(CN).In this Pt_(1)-Co_(1)/CN bimetallic single-atom catalyst,the noble-metal active sites are maximized,and the single-atomic Co_(1)N_4sites are tuned to Co_(1)N_3sites by photogenerated electrons arising from the introduced single-atomic Pt_(1)N_4sites.Mechanism studies and density functional theory(DFT)calculations reveal that the 3d orbitals of Co_(1)N_3single sites are filled with unpaired d-electrons,which lead to the improved visible-light response,carrier separation and charge migration for CN photocatalysts.Thereafter,the protons adsorption and activation are promoted.Taking this advantage of long-range electron synergy in bimetallic single atomic sites,the photocatalytic hydrogen evolution activity over Pt_(1)-Co_(1)/CN achieves 915.8 mmol g^(-1)Pt h^(-1),which is 19.8 times higher than Co_(1)/CN and 3.5 times higher to Pt_(1)/CN.While this electron-synergistic effect is not so efficient for Pt nanoclusters.These results demonstrate the synergistic effect at electron-level and provide electron-level guidance for the design of efficient photocatalysts.
基金Shandong Excellent Young Scientists Fund Program(Oversea),Grant/Award Number:2022S02002Jinan“5150”Talent Program,Grant/Award Number:2022C01001+1 种基金Pearl River Talent Recruitment Program,Grant/Award Number:2019QN01L096Guangdong Innovative and Entrepreneurial Research Team Program,Grant/Award Number:2019ZT08L075。
文摘The practical application of lithium–sulfur batteries(LSBs)is severely hindered by the undesirable shuttling of lithium polysulfides(LiPSs)and sluggish redox kinetics of sulfur species.Herein,a series of ultrathin singleatomic tungsten-doped Co_(3)O_(4)(Wx-Co_(3)O_(4))nanosheets as catalytic additives in the sulfur cathode for LSBs are rationally designed and synthesized.Benefiting from the enhanced catalytic activity and optimized electronic structure by W doping,the Wx-Co_(3)O_(4) not only reduces the shuttling of LiPSs but also decreases the energy barrier of sulfur redox reactions of sulfur species,leading to accelerated electrode kinetic.As a result,LSB cathodes with the use of 5.0 wt%W0.02-Co_(3)O_(4) as the electrocatalyst show the high reversible capacities of 1217.0 and 558.6 mAh g^(-1) at 0.2 and 5.0 C,respectively,and maintain a high reversible capacity of 644.6 mAh g^(-1) at 1.0 C(1.0 C=1675 mA g^(-1))after 500 cycles.With a high sulfur loading of 5.5 mg cm^(-2) and electrolyte–electrode ratio of 8μL_(electrolyte) mg_(sulfur)^(-1),the 5.0 wt%W_(0.02)-Co_(3)O_(4)-based sulfur cathode also retains a high reversible areal capacity of 3.86 mAh cm^(-2) at 0.1 C after 50 cycles with an initial capacity retention of 84.7%.
基金National Natural Science Foundation of China,Grant/Award Numbers:22075203,22279079,21905179Guangdong Science and Technology Department Program,Grant/Award Number:2021QN02L252+1 种基金Shenzhen Science and Technology Department Program,Grant/Award Numbers:20220810133521001,20220809165014001Natural Science Foundation of SZU,Grant/Award Numbers:000002111605,000002112215。
文摘A fuel cell is an energy conversion device that can continuously input fuel and oxidant into the device through an electrochemical reaction to release electrical energy.Although noble metals show good activity in fuel cell-related electrochemical reactions,their ever-increasing price considerably hinders their industrial application.Improvement of atom utilization efficiency is considered one of the most effective strategies to improve the mass activity of catalysts,and this allows for the use of fewer catalysts,saving greatly on the cost.Thus,single-atom catalysts(SACs)with an atom utilization efficiency of 100%have been widely developed,which show remarkable performance in fuel cells.In this review,we will describe recent progress on the development of SACs for membrane electrode assembly of fuel cell applications.First,we will introduce several effective routes for the synthesis of SACs.The reaction mechanism of the involved reactions will also be introduced as it is highly determinant of the final activity.Then,we will systematically summarize the application of Pt group metal(PGM)and nonprecious group metal(non-PGM)catalysts in membrane electrode assembly of fuel cells.This review will offer numerous experiences for developing potential industrialized fuel cell catalysts in the future.
基金supported by the National Natural Science Foundation of China (Grant No.12164009),which is received by Xuefei Liuthe Guizhou Science and Technology Foundation-ZK[2022]General 308,which is received by Xuefei Liu+2 种基金Top scientific and technological talents in Guizhou Province of Qian Jiaoji[2022]No.078,which is received by Xuefei LiuGraduate Research Fund Project of Guizhou Province (YJSKYJJ[2021]088),which is received by Tianyun Liuthe Haihe Laboratory of Sustainable Chemical Transformation for financial support。
文摘As a zero-carbon fuel,hydrogen can be produced via electrochemical water splitting using clean electric energy by the hydrogen evolution reaction(HER)process.The ultimate goal of HER catalyst is to replace the expensive Pt metal benchmark with a cheap one with equivalent activities.In this work,we investigated the possibility of HER process on single-atom catalysts(SACs)doped on two-dimensional(2D)GaPS_(4)materials,which have a large intrinsic band gap that can be regulated by doping and tensile strain.Based on the machine learning regression analysis,we can expand the prediction of HER performance to more catalysts without expensive DFT calculation.The electron affinity and first ionization energy are the two most important descriptors related to the HER behavior.Furthermore,constrain molecular dynamics with solvation models and constant potentials were applied to understand the dynamics barrier of HER process of Pt SAC on GaPS_(4)materials.These findings not only provide important insights into the catalytic properties of single-atom catalysts on GaPS_(4)2D materials,but also provides theoretical guidance paradigm for exploration of new catalysts.
基金supported by the National Natural Science Foundation of China (Grant Nos.62006219 and 62001266)Guangdong Innovative and Entrepre-neurial Research Team Program (grant No.2017ZT07C341)+2 种基金the Bureau of Industry and Information Technology of Shenzhen for the 2017 Graphene Manufacturing Innovation Center Project (No.201901171523)the China Postdoctoral Science Foundation (No.2020M680506)Guangdong Basic and Applied Basic Research Foundation (No.2020A1515110338).
文摘Various strategies,including controls of morphology,oxidation state,defect,and doping,have been developed to improve the performance of Cu-based catalysts for CO_(2) reduction reaction(CO_(2)RR),generating a large amount of data.However,a unified understanding of underlying mechanism for further optimization is still lacking.In this work,combining first-principles calculations and machine learning(ML)techniques,we elucidate critical factors influencing the catalytic properties,taking Cu-based single atom alloys(SAAs)as examples.Our method relies on high-throughput calculations of 2669 CO adsorption configurations on 43 types of Cu-based SAAs with various surfaces.Extensive ML analyses reveal that low generalized coordination numbers and valence electron number are key features to determine catalytic performance.Applying our ML model with cross-group learning scheme,we demonstrate the model generalizes well between Cu-based SAAs with different alloying elements.Further,electronic structure calculations suggest surface negative center could enhance CO adsorption by back donating electrons to antibonding orbitals of CO.Finally,several SAAs,including PCu,AgCu,GaCu,ZnCu,SnCu,GeCu,InCu,and SiCu,are identified as promising CO_(2)RR catalysts.Our work provides a paradigm for the rational design and fast screening of SAAs for various electrocatalytic reactions.
基金This project was supported by the National Natural Science Foundation of China(U19A2017,22272206,51976143)Natural Science Foundation of Hunan Province(S2021JJMSXM3153).
文摘Electrochemical carbon dioxide reduction reaction(CO_(2)RR)provides an attractive approach to carbon capture and utilization for the production high-value-added products.However,CO_(2)RR still suffers from poor selectivity and low current density due to its sluggish kinetics and multitudinous reaction pathways.Single-atom catalysts(SACs)demonstrate outstanding activity,excellent selectivity,and remarkable atom utilization efficiency,which give impetus to the search for electrocatalytic processes aiming at high selectivity.There appears significant activity in the development of efficient SACs for CO_(2)RR,while the density of the atomic sites remains a considerable barrier to be overcome.To construct high-metal-loading SACs,aggregation must be prevented,and thus novel strategies are required.The key to creating high-density atomically dispersed sites is designing enough anchoring sites,normally defects,to stabilize the highly mobile separated metal atoms.In this review,we summarized the advances in developing high-loading SACs through defect engineering,with a focus on the synthesis strategies to achieve high atomic site loading.Finally,the future opportunities and challenges for CO_(2)RR in the area of high-loading single-atom electrocatalysts are also discussed.
基金financially supported by the“National Natural Science Foundation of China”(52304072)“Funded by Shandong Postdoctora1 Science Foundation”(SDBX2023019)+1 种基金the“Fundamental Research Funds for the Central Universities”(23CX06022A)the“Applied Research Project of Qingdao Postdoctoral Researchers”(QDBSH20230202010).
文摘The stimuli-responsive anticorrosion coatings have drawn great attention as a prospective corrosion protection approach due to their smart self-repairing properties.In contrast to passive protection mechanism based on post-corrosion microenvironmental changes,a unique active protection strategy based on nanocatalytic oxygen depletion is proposed in this work to inhibit the occurrence of corrosion.Porous FeeNeC catalysts with outstanding oxygen reduction reaction(ORR)activity(half-wave potential of 0.89 V)is firstly synthesized through pre-coordination with organosilane precursor to obtain homogeneously distributed active sites.When this catalyst is introduced into the coating matrix,uniformly distributed FeeNeC not only compensates the defects but plays a crucial role in adsorption and consumption of diffused oxygen in the coating.Under this dual action,the penetration of corrosive medium,especially oxygen,through coating to metal substrate is greatly suppressed,resulting in effective corrosion inhibition and a significant increase in corrosion resistance of the composite coating compared to pure epoxy coating.This work provides a new perspective and the starting point for the design of high-performance smart coating with active anticorrosion properties.
基金Financial support was provided by the Guangdong College Students’Innovative Project(202110580014)the Guangdong “Climbing”Program for Research Items(pdjh2021b0544)。
文摘The next-generation energy storage systems such as fuel cells,metal-air batteries,and alkali metal(Li,Na)-chalcogen(S,Se)batteries have received increasing attention owing to their high energy density and low cost.However,one of the main obstacles of these systems is the poor reaction kinetics in the involved chemical reactions.Therefore,it is essential to incorporate suitable and efficient catalysts into the cell.These years,single-atom catalysts(SACs)are emerging as a frontier in catalysis due to their maximum atom efficiency and unique reaction selectivity.For SACs fabrication,metal-organic frameworks(MOFs)have been confirmed as promising templates or precursors due to their high metal loadings,structural adjustability,porosity,and tailorable catalytic site.In this review,we summarize effective strategies for fabricating SACs by MOFs with corresponding advanced characterization techniques and illustrate the key role of MOFs-based SACs in these batteries by explaining their reaction mechanisms and challenges.Finally,current applications,prospects,and opportunities for MOFs-based SACs in energy storage systems are discussed.
基金supported by National Key Research and Development Program of China(2021YFA1500500,2019YFA0405600,2017YFA0204904,2019YFA0405602,and 2017YFA0403402)the National Science Fund for Distinguished Young Scholars(21925204)+8 种基金the National Natural Science Foundation of China(21972132,U1732149,U19A2015,U1732272,21673214,92045301,and 21902149)the Fundamental Research Funds for the Central Universities(20720220010)the Provincial Key Research and Development Program of Anhui(202004a05020074)the Anhui Natural Science Foundation for Young Scholars(2208085QB52)K.C.Wong Education(GJTD2020-15)the Hefei Municipal Natural Science Foundation(2021018)the DNL Cooperation Fund,CAS(DNL202003)Users with Excellence Program of Hefei Science Center CAS(2020HSCUE001)USTC Research Funds of the Double First-Class Initiative(YD2340002002)。
文摘The demand for clean and sustainable energy has encouraged the production of hydrogen from water electrolyzers.To overcome the obstacle to improving the efficiency of water electrolyzers,it is highly desired to fabricate active electrocatalysts for the sluggish oxygen evolution process.However,there is generally an intrinsic gap between the as-prepared and real electrocatalysts due to structure evolution under the oxidative reaction conditions.Here,we combine in-situ anionic leaching and atomic deposition to realize single-atom catalysts with self-optimized structures.The introduced F ions facilitate structural transformation from Co(OH)xF into CoOOH(F),which generates an amorphous edge surface to provide more anchoring sites for Ir single atoms.Meanwhile,the in-situ anionic leaching of F ions elevates the Co valence state of Ir_(1)/CoOOH(F)more significantly than the counterpart without F ions(Ir_(1)/CoOOH),leading to stronger adsorption of oxygenated intermediates.As revealed by electrochemical measurements,the increased Ir loading together with the favored adsorption of*OH intermediates improve the catalytic activity of Ir_(1)/CoOOH(F).Specifically,Ir_(1)/CoOOH(F)delivered a current density of 10 mA cm-2at an overpotential of 238 mV,being lower than 314 mV for Ir_(1)/CoOOH.The results demonstrated the facility of the in-situ optimization process to optimize catalyst structure for improved performance.
基金supported by the National Natural Science Foundation of China (NSFC,22172082,21978137,22102074,and 21878162)Natural Science Foundation of Tianjin (20JCZDJC00770)+1 种基金Postdoctoral Research Foundation of China (2021M701776)NCC Fund (NCC2020FH05)。
文摘In this work,DFT calculations were used firstly to simulate the nitrogen coordinated metal single-atom catalysts(M-N_(x)SACs,M=Hg,Cu,Au,and Ru) to predict their catalytic activities in acetylene hydrochlorination.The DFT results showed that Ru-N_(x)SACs had the best catalytic performance among the four catalysts,and Ru-N_(x)SACs could effectively inhibit the reduction of ruthenium cation.To verify the DFT results,Ru-N_(x)SACs were fabricated by pyrolyzing MOFs in-situ spatially confined metal precursors.The N coordination environment could be controlled by changing the pyrolysis temperature.Catalytic performance tests indicated that low N coordination number(Ru-N_(2),Ru-N_(3))exhibited excellent catalytic activity and stability compared to RuCl_(3)catalyst.DFT calculations further revealed that Ru-N_(2)and Ru-N_(3)had a tendency to activate HCl at the first step of reaction,whereas Ru-N4tended to activate C_(2)H_(2).These findings will serve as a reference for the design and control of metal active sites.
基金the financial support from the National Natural Science Foundation of China (52076045)the Ministry of Science and Technology of China (2019YFC1906700, 2018YFC1902600)the support from “Zhishan Scholar” of Southeast University。
文摘Developing efficient electrocatalysts for converting dinitrogen to ammonia through electrocatalysis is of significance to the decentralized ammonia production. Here, through high-throughput density functional theory calculations, we demonstrated that the interfacial modulation of hexagonal boron nitride/graphene(hBN-graphene) could sufficiently improve the catalytic activity of the single transition metal atom catalysts for nitrogen reduction reaction(NRR). It was revealed that Re@hBN-graphene and Os@hBN-graphene possessed remarkable NRR catalytic activity with low limiting potentials of 0.29 V and 0.33 V, respectively. Furthermore, the mechanism of the enhanced catalytic activity was investigated based on various descriptors of the adsorption energies of intermediates, where the synergistic effect of hBN and graphene in the hybrid substrate was found to play a key role. Motivated by the synergistic effect of hybrid substrate in single-atom catalysts, a novel strategy was proposed to efficiently design dual-atom catalysts by integrating the merits of both metal components. The as-designed dual-atom catalyst Fe-Mo@hBN exhibited more excellent NRR catalytic performance with a limiting potential of 0.17 V, manifesting the solidity of the design strategy. Our findings open new avenues for the search of heterostructure substrates for single-atom catalysts and the efficient design of dualatom catalysts for NRR.