Density functional theory calculations were used to unravel the mechanism of CO_2 electroreduction on SnO_x surfaces. Under highly reducing conditions(<-0.6 V vs. RHE), the SnO(101) surface with oxygen vacancies is...Density functional theory calculations were used to unravel the mechanism of CO_2 electroreduction on SnO_x surfaces. Under highly reducing conditions(<-0.6 V vs. RHE), the SnO(101) surface with oxygen vacancies is likely the active phase for CO_2 reduction. We showed that the proton-electron transfer to adsorbed *CO_2 forming *OCHO, a key intermediate for producing HCOOH, is energetically more favorable than the formation of *COOH, justifying the selectivity trends observed on Sn-based electrocatalysts. With linear scaling relations, we propose the free formation energy of *CO_2 at the oxygen vacancy as the reactivity descriptor. By engineering the strain of the SnO(101) surface, the selectivity towards HCOOH can be further optimized at reduced overpotentials.展开更多
The excessive emission of CO_(2) has caused many environmental issues and is severely threatening the eco-system.CO_(2) electroreduction reaction(CO_(2) RR) that driven by sustainable power is an ideal route for reali...The excessive emission of CO_(2) has caused many environmental issues and is severely threatening the eco-system.CO_(2) electroreduction reaction(CO_(2) RR) that driven by sustainable power is an ideal route for realizing the net reduction of CO_(2) and carbon recycle.Developing efficient electrocatalysts with low cost and high performance is critical for the wide applications of CO_(2) RR electrolysis.Among the various explored CO_(2) RR catalysts,non-noble metal(NNM)-based nanomaterials have drawn increasing attentions due to the remarkable performance and low cost.In this mini-review,the recent advances of NNM-based CO_(2) RR catalysts are summarized,and the catalysts are classified based on their corresponding reduction products.The preparation strategies for engineering the electrocatalysts are introduced,and the relevant CO_(2) RR mechanisms are discussed in detail.Finally,the current challenges in CO_(2) RR research are presented,and some perspectives are proposed for the future development of CO_(2) RR technology.This mini-review introduces the recent advances and frontiers of NNM-based CO_(2) RR catalysts,which should shed light on the further exploration of efficient CO_(2) RR electrocatalysts.展开更多
Electrochemically converting CO_(2) molecules into valuable chemicals and fuels opens up a promising route to utilize CO_(2) source.To overcome the low efficiency and durability that hinder its practical applications,...Electrochemically converting CO_(2) molecules into valuable chemicals and fuels opens up a promising route to utilize CO_(2) source.To overcome the low efficiency and durability that hinder its practical applications,tremendous research efforts have been devoted to nano‐level or atomic‐level catalyst design.The advent of metal-organic frameworks(MOFs)provides novel opportunities for CO_(2) reduction catalysts,which may integrate the respective advantages of traditional catalysts and single‐atom catalysts.In this review,we summarize the recent advances in two‐dimensional(2D)π‐conjugated MOF catalysts and discuss their practical applications in CO_(2) reduction reaction(CO_(2)RR).First,we systematically introduce the development of electrocatalysts for CO_(2)RR applications.Meanwhile,various types of 2D porphyrin/phthalocyanine‐based MOFs and corresponding electrocatalytic performances arising from activesite engineering,surface reconstruction,and thickness control are briefly overviewed.Finally,we highlight their major challenges and opportunities facing CO_(2)RR,and hope that this review can offer new insight into MOF catalyst design.展开更多
Tandem electrocatalysis is an emerging concept for effective electrochemical CO_(2) reduction reaction(CO_(2)RR)towards multicarbons(C_(2+)).This decouples the multiple steps of CO_(2)-to-C_(2+)into two steps of CO_(2...Tandem electrocatalysis is an emerging concept for effective electrochemical CO_(2) reduction reaction(CO_(2)RR)towards multicarbons(C_(2+)).This decouples the multiple steps of CO_(2)-to-C_(2+)into two steps of CO_(2)-to-CO and CO-to-C_(2+)catalyzed by individual catalysts,to improve the Faradic efficiency(FE).However,due to the mass-transport limitation of CO from the generation site to the long-distance consumption site,such a strategy still remains challenge for high-rate production of C_(2+)products.Herein,we designed CuO/Ni single atoms tandem catalyst,which made the catalytic sites of Ni and Cu for independently catalyzing CO_(2)-to-CO and CO-to-C_(2+)compactly neighbored,enabling the in-situ generation and rapid consumption of CO.The CuO/Ni SAs tandem catalyst achieved a particularly high partial current density of C_(2+)products(1220.8 mA/cm^(2)),while still maintained outstanding C_(2+)products FE(81.4%)and excellent selectivities towards ethylene(FE 54.1%)and ethanol(FE 28.8%),enabling the profitable production of multicarbons by CO_(2)RR.展开更多
Capturing CO_(2) from the atmosphere and converting it into fuels are an effi cient strategy to stop the deteriorating greenhouse eff ect and alleviate the energy crisis.Among various CO_(2) conversion approaches,elec...Capturing CO_(2) from the atmosphere and converting it into fuels are an effi cient strategy to stop the deteriorating greenhouse eff ect and alleviate the energy crisis.Among various CO_(2) conversion approaches,electrocatalytic CO_(2) reduction reaction(CO_(2) RR)has received extensive attention because of its mild operating conditions.However,the high onset potential,low selectivity toward multi-carbon products and poor cruising ability of CO_(2) RR impede its development.To regulate product distribution,previous studies performed electrocatalyst modifi cation using several universal methods,including composition manipulation,morphology control,surface modifi cation,and defect engineering.Recent studies have revealed that the cathode and electrolytes infl uence the selectivity of CO_(2) RR via pH changes and ionic eff ects,or by directly participating in the reduction pathway as cocatalysts.This review summarizes the state-of-the-art optimization strategies to effi ciently enhance CO_(2) RR selectivity from two main aspects,namely the cathode electrocatalyst and the electrolyte.展开更多
Porous crystalline metal-organic frameworks(MOFs)and covalent organic frameworks(COFs)are promising platforms for electrocatalytic reduction of CO_(2)(CO_(2)RR)due to their large CO_(2)adsorption uptakes and periodica...Porous crystalline metal-organic frameworks(MOFs)and covalent organic frameworks(COFs)are promising platforms for electrocatalytic reduction of CO_(2)(CO_(2)RR)due to their large CO_(2)adsorption uptakes and periodically arranged single active sites.However,the applications in CO_(2)RR of the traditional MOFs and COFs are greatly limited by their low electron conductivity.In recent years,numerous types of MOFs and COFs with high intrinsic conductivity have been rationally designed and successfully constructed,and some of them have been applied in CO_(2)RR.In this review,the applications of conductive MOFs and COFs in CO_(2)RR have been summarized.The conductive MOFs and COFs can be categorized according to the methods,in which the conductivity is enhanced,such as constructing fullyπ-conjugated backbones,donor-acceptor heterojunction,enhancing theπ-πstacking interactions between organic moieties and/or the introduction of guest molecules.展开更多
To improve the atomic utilization of metals and reduce the cost of industrialization,the one-step total monoatomization of macroscopic bulk metals,as opposed to nanoscale metals,is effective.In this study,we used a th...To improve the atomic utilization of metals and reduce the cost of industrialization,the one-step total monoatomization of macroscopic bulk metals,as opposed to nanoscale metals,is effective.In this study,we used a thermal diffusion method to directly convert commercial centimeter-scale Ni foam to porous Ni single-atom-loaded carbon nanotubes(CNTs).As expected,owing to the coating of single-atom on porous,highly conductive CNT carriers,Ni single-atom electrocatalysts(Ni-SACs)exhibit extremely high activity and selectivity in CO_(2)electroreduction(CO_(2)RR),yielding a current density of>350 mA/cm^(2),a selectivity for CO of>91%under a flow cell configuration using a 1 M potassium chloride(KCl)electrolyte.Based on the superior activity of the Ni-SACs electrocatalyst,an integrated gas-phase electrochemical zero-gap reactor was introduced to generate a significant amount of CO current for potential practical applications.The overall current can be increased to 800 mA,while maintaining CO Faradaic efficiencies(FEs)at above 90%per unit cell.Our findings and insights on the active site transformation mechanism for macroscopic bulk Ni foam conversion into single atoms can inform the design of highly active single-atom catalysts used in industrial CO_(2)RR systems.展开更多
Single-atom catalysts(SACs),with the utmost atom utilization,have attracted extensive interests for various catalytic applications.The coordination environment of SACs has been recognized to play a vital role in catal...Single-atom catalysts(SACs),with the utmost atom utilization,have attracted extensive interests for various catalytic applications.The coordination environment of SACs has been recognized to play a vital role in catalysis while their precise regulation at atomic level remains an immense challenge.Herein,a post metal halide modification(PMHM)strategy has been developed to construct Ni-N4 sites with axially coordinated halogen atoms,named Ni1-N-C(X)(X=CI,Br,and I),on pre-synthetic nitrogen-doped carbon derived from metal-organic frameworks.The axial halogen atoms with distinct electronegativity can break the symmetric charge distribution of planar Ni-N4 sites and regulate the electronic states of central Ni atoms in Ni1-N-C(X)(X=Cl,Br,and I).Significantly,the Ni1-N-C(CI)catalyst,decorated with the most electronegative Cl atoms,exhibits Faradaic efficiency of CO up to 94.7%in electrocatalytic CO_(2) reduction,outperforming Ni1-N-C(Br)and Ni1-N-C(I)catalysts.Moreover,Ni1-N-C(CI)also presents superb performance in Zn-CO_(2) battery with ultrahigh CO selectivity and great durability.Theoretical calculations reveal that the axially coordinated Cl atom remarkably facilitates*COOH intermediate formation on single-atom Ni sites,thereby boosting the CO_(2) reduction performance of Ni1-N-C(CI).This work offers a facile strategy to tailor the axial coordination environments of SACs at atomic level and manifests the crucial role of axial coordination microenvironments in catalysis.展开更多
Cu-based catalysts are the most promising candidates for electrochemical CO_(2)reduction(CO_(2)RR)to multi-carbon(C_(2))products.Optimizing the C-C coupling process,the rate-determining step for C_(2)product generatio...Cu-based catalysts are the most promising candidates for electrochemical CO_(2)reduction(CO_(2)RR)to multi-carbon(C_(2))products.Optimizing the C-C coupling process,the rate-determining step for C_(2)product generation,is an important strategy to improve the production and selectivity of the C_(2)products.In this study,we determined that the local electric field can promote the C-C coupling reaction and enhance CO_(2)electroreduction to C_(2)products.First,finite-element simulations indicated that the high curvature of the Cu nanoneedles results in a large local electric field on their tips.Density functional theory(DFT)calculations proved that a large electric field can promote C-C coupling.Motivated by this prediction,we prepared a series of Cu catalysts with different curvatures.The Cu nanoneedles(NNs)exhibited the largest number of curvatures,followed by the Cu nanorods(NRs),and Cu nanoparticles(NPs).The Cu NNs contained the highest concentration of adsorbed K+,which resulted in the highest local electric field on the needles.CO adsorption sensor tests indicated that the Cu NNs exhibited the strongest CO adsorption ability,and in-situ Fourier-transform infrared spectroscopy(FTIR)showed the strongest*COCO and*CO signals for the Cu NNs.These experimental results demonstrate that high-curvature nanoneedles can induce a large local electric field,thus promoting C-C coupling.As a result,the Cu NNs show a maximum FEC_(2)of 44%for CO_(2)RR at a low potential(-0.6 V vs.RHE),which is approximately 2.2 times that of the Cu NPs.This work provides an effective strategy for enhancing the production of multi-carbon products during CO_(2)RR.展开更多
Catalytic conversion of CO_(2)into chemicals and fuels is a viable method to reduce carbon emissions and achieve carbon neutrality.Through thermal catalysis,electrocatalysis,and photo(electro)catalysis,CO_(2)can be co...Catalytic conversion of CO_(2)into chemicals and fuels is a viable method to reduce carbon emissions and achieve carbon neutrality.Through thermal catalysis,electrocatalysis,and photo(electro)catalysis,CO_(2)can be converted into a wide range of valuable products,including CO,formic acid,methanol,methane,ethanol,acetic acid,propanol,light olefi ns,aromatics,and gasoline,as well as fi ne chemicals.In this mini-review,we summarize the recent progress in heterogeneous catalysis for CO_(2)conversion into chemicals and fuels and highlight some representative studies of diff erent conversion routes.The structure-performance correlations of typical catalytic materials used for the CO_(2)conversion reactions have been revealed by combining advanced in situ/operando spectroscopy and microscopy characterizations and density functional theory cal-culations.Catalytic selectivity toward a single CO_(2)reduction product/fraction should be further improved at an industrially relevant CO_(2)conversion rate with considerable stability in the future.展开更多
Copper(Cu)is considered to be the most effective catalyst for electrochemical conversion of carbon dioxide(CO_(2))into value-added hydrocarbons,but its stability still faces considerable challenge.Here,we report the p...Copper(Cu)is considered to be the most effective catalyst for electrochemical conversion of carbon dioxide(CO_(2))into value-added hydrocarbons,but its stability still faces considerable challenge.Here,we report the poisoning effect of carbon deposition during CO_(2)reduction on the active sites of Cu electrodea critical deactivation factor that is often overlooked.We find that,*C,an intermediate toward methane formation,could desorb on the electrode surface to form carbon species.We reveal a strong correlation between the formation of methane and the carbon deposition,and the reaction conditions favoring methane production result in more carbon deposition.The deposited carbon blocks the active sites and consequently causes rapid deterioration of the catalytic performance.We further demonstrate that the carbon deposition can be mitigated by increasing the roughness of the electrode and increasing the pH of the electrolyte.This work offers a new guidance for designing more stable catalysts for CO_(2)reduction.展开更多
Electroreduction of carbon dioxide into fuels and feedstocks with renewable energy is an attractive route to mitigate carbon emission and solve energy crisis.However,how to improve the selectivity of high‐value multi...Electroreduction of carbon dioxide into fuels and feedstocks with renewable energy is an attractive route to mitigate carbon emission and solve energy crisis.However,how to improve the selectivity of high‐value multicarbon products is still challenging.Here,we demonstrate that the high‐index crystalline surface of copper could be designed and obtained through a simple square‐wave potential treatment on copper nanowires,which is beneficial to improve the selectivity of multi‐carbon products,especially the reaction route towards ethylene.The Faradaic efficiency of C_(2+)products can reach nearly 60%,and hydrogen can be suppressed to below 20%.Density functional theory(DFT)calculations reveal that(311)high‐index facet can activate CO_(2) effectively and promote adsorption of the*COCOH intermediate on copper for ethylene formation,therefore improves the selectivity of ethylene and inhibits the competing hydrogen evolution reaction.This method can be extended to the design of other catalytic systems and has inspirations for other electrochemical catalytic reactions.展开更多
Regulating the electronic structure of Bi-based materials by alloying engineering is promising to promote the electrocatalytic activity,but it remains some challenges to be solved.In this study,a facile electrochemica...Regulating the electronic structure of Bi-based materials by alloying engineering is promising to promote the electrocatalytic activity,but it remains some challenges to be solved.In this study,a facile electrochemical co-deposition strategy is developed to synthesize the bimetallic Bi_(9)Cu_(1) alloy nanosheet on carbon cloth(Bi_(9)Cu_(1)/CC),which represents a novel self-supporting electrode for the electrocatalytic carbon dioxide(CO_(2))reduction reaction(CO_(2)RR).The Bi_(9)Cu_(1)/CC catalyst has achieved a remarkable catalytic performance with high Faradaic efficiencies(FE)of over 90%for formate at wide potentials from-0.7 to-1.2 V vs.reversible hydrogen electrode(RHE).Moreover,the reversible Zn-CO_(2) battery can be driven by Bi_(9)Cu_(1)/CC cathode with a largest power density of 1.4 mW·cm^(-2),and superior operating stability.The systematic characterizations and electrochemical results confirm that the improved catalytic active sites,the enhanced mass/charge transport and the optimal reaction kinetics of Bi nanosheet are realized for CO_(2)RR by Cu alloying.In situ attenuated total reflection infrared(ATR-IR)result confirms the bimetallic Bi-Cu active sites prefer to follow the^(*)OCHO conversion pathway.The density functional theory(DFT)calculations suggest that the Cu alloying contributes to the increased density of states near the Fermi surface of Bi and the optimized adsorption of^(*)OCHO intermediates on the Bi sites,resulting in the excellent catalytic performance.展开更多
Reliable technologies for CO_(2) capture and conversion(C3) are of vital importance for the establishment of a sustainable society.Metal-organic framework(MOF) composites have shown their compelling potentials for C3 ...Reliable technologies for CO_(2) capture and conversion(C3) are of vital importance for the establishment of a sustainable society.Metal-organic framework(MOF) composites have shown their compelling potentials for C3 due to the plentiful reticular chemistry of MOF structures and the synergistic catalysis between MOFs and the functional guests.This review focuses on the syntheses and catalytic applications towards C3 of MOF composites,which is divided into three sections.The first section gives a brief introduction about synthetic strategies of MOF composites.The second section discusses the recent progress of MOF composites in C3,including CO_(2) chemical fixation,hydrogenation,photoreduction,electro reduction and photoelectro reduction.The third section summarizes the challenges and future prospects of MOF composites for C3.We hope that this review cannot only provide an inspiration for the rational design of MOF composites for C3,but also stimulate more and more research works in this emerging area.展开更多
Electrochemical reduction of CO_(2) to formic acid(HCOOH)is an important route for storing renewable energy and achieving carbon neutrality.Herein,we propose the continuous production of HCOOH solution from electrocat...Electrochemical reduction of CO_(2) to formic acid(HCOOH)is an important route for storing renewable energy and achieving carbon neutrality.Herein,we propose the continuous production of HCOOH solution from electrocatalytic CO_(2) reduction using highly mesoporous bismuth oxide(Bi_(2)O_(3))nanosheets as an electrocatalyst and membrane electrode assembly with solid-state electrolyte as an electrolyzer.Precisely,0.1 M of HCOOH solution could be produced continuously at a current density of -56 mA cm^(-2) for at least 43 h.The underlying mechanism for the high performance of the electrocatalytic system was investigated by experimental studies and theoretical calculations.展开更多
基金financial support from the American Chemical Society Petroleum Research Fund (ACS PRF 55581-DNI5)the Institute for Critical Technology and Applied Science (ICTAS-J0663175)the NSF CBET Catalysis and Biocatalysis Program (CBET-1604984)
文摘Density functional theory calculations were used to unravel the mechanism of CO_2 electroreduction on SnO_x surfaces. Under highly reducing conditions(<-0.6 V vs. RHE), the SnO(101) surface with oxygen vacancies is likely the active phase for CO_2 reduction. We showed that the proton-electron transfer to adsorbed *CO_2 forming *OCHO, a key intermediate for producing HCOOH, is energetically more favorable than the formation of *COOH, justifying the selectivity trends observed on Sn-based electrocatalysts. With linear scaling relations, we propose the free formation energy of *CO_2 at the oxygen vacancy as the reactivity descriptor. By engineering the strain of the SnO(101) surface, the selectivity towards HCOOH can be further optimized at reduced overpotentials.
基金financially supported by the National Natural Science Foundation of China(Nos.52001227 and 51972224)the China Postdoctoral Science Foundation(No.2019M661014)。
文摘The excessive emission of CO_(2) has caused many environmental issues and is severely threatening the eco-system.CO_(2) electroreduction reaction(CO_(2) RR) that driven by sustainable power is an ideal route for realizing the net reduction of CO_(2) and carbon recycle.Developing efficient electrocatalysts with low cost and high performance is critical for the wide applications of CO_(2) RR electrolysis.Among the various explored CO_(2) RR catalysts,non-noble metal(NNM)-based nanomaterials have drawn increasing attentions due to the remarkable performance and low cost.In this mini-review,the recent advances of NNM-based CO_(2) RR catalysts are summarized,and the catalysts are classified based on their corresponding reduction products.The preparation strategies for engineering the electrocatalysts are introduced,and the relevant CO_(2) RR mechanisms are discussed in detail.Finally,the current challenges in CO_(2) RR research are presented,and some perspectives are proposed for the future development of CO_(2) RR technology.This mini-review introduces the recent advances and frontiers of NNM-based CO_(2) RR catalysts,which should shed light on the further exploration of efficient CO_(2) RR electrocatalysts.
基金National Key R&D Program of China,Grant/Award Numbers:2017YFA0700101,2016YFA0202801National Natural Science Foundation of China,Grant/Award Number:22035004+1 种基金China Postdoctoral Science Foundation,Grant/Award Number:2020M680511XPLORED PRIZE。
文摘Electrochemically converting CO_(2) molecules into valuable chemicals and fuels opens up a promising route to utilize CO_(2) source.To overcome the low efficiency and durability that hinder its practical applications,tremendous research efforts have been devoted to nano‐level or atomic‐level catalyst design.The advent of metal-organic frameworks(MOFs)provides novel opportunities for CO_(2) reduction catalysts,which may integrate the respective advantages of traditional catalysts and single‐atom catalysts.In this review,we summarize the recent advances in two‐dimensional(2D)π‐conjugated MOF catalysts and discuss their practical applications in CO_(2) reduction reaction(CO_(2)RR).First,we systematically introduce the development of electrocatalysts for CO_(2)RR applications.Meanwhile,various types of 2D porphyrin/phthalocyanine‐based MOFs and corresponding electrocatalytic performances arising from activesite engineering,surface reconstruction,and thickness control are briefly overviewed.Finally,we highlight their major challenges and opportunities facing CO_(2)RR,and hope that this review can offer new insight into MOF catalyst design.
基金supported by the National Key R&D Program of China(2020YFA0710200)the DNL Cooperation Fund,Chinese Academy of Sciences(DNL201918)+6 种基金the Fundamental Research Funds for the Central Universities(WK2060000004,WK2060000021,WK2060000025,KY2060000180,and KY2060000195)the National Natural Science Foundation of China(21805191)Pengcheng Scholar Program,China Postdoctoral Science Foundation(2019M653004)Shenzhen Peacock Plan(KQTD2016053112042971)Shenzhen Science and Technology Program(JCYJ20190808142001745,JCYJ20200812160737002,and RCJC20200714114434086)Guangdong Basic and Applied Basic Research Foundation(2020A1515010982)Shenzhen Stable Support Project(20200812122947002)。
文摘Tandem electrocatalysis is an emerging concept for effective electrochemical CO_(2) reduction reaction(CO_(2)RR)towards multicarbons(C_(2+)).This decouples the multiple steps of CO_(2)-to-C_(2+)into two steps of CO_(2)-to-CO and CO-to-C_(2+)catalyzed by individual catalysts,to improve the Faradic efficiency(FE).However,due to the mass-transport limitation of CO from the generation site to the long-distance consumption site,such a strategy still remains challenge for high-rate production of C_(2+)products.Herein,we designed CuO/Ni single atoms tandem catalyst,which made the catalytic sites of Ni and Cu for independently catalyzing CO_(2)-to-CO and CO-to-C_(2+)compactly neighbored,enabling the in-situ generation and rapid consumption of CO.The CuO/Ni SAs tandem catalyst achieved a particularly high partial current density of C_(2+)products(1220.8 mA/cm^(2)),while still maintained outstanding C_(2+)products FE(81.4%)and excellent selectivities towards ethylene(FE 54.1%)and ethanol(FE 28.8%),enabling the profitable production of multicarbons by CO_(2)RR.
基金This work was financially supported by the National Natural Science Foundation of China(Nos.22071173,21871206)the Natural Science Foundation of Tianjin City(No.17JCJQJC44700).
文摘Capturing CO_(2) from the atmosphere and converting it into fuels are an effi cient strategy to stop the deteriorating greenhouse eff ect and alleviate the energy crisis.Among various CO_(2) conversion approaches,electrocatalytic CO_(2) reduction reaction(CO_(2) RR)has received extensive attention because of its mild operating conditions.However,the high onset potential,low selectivity toward multi-carbon products and poor cruising ability of CO_(2) RR impede its development.To regulate product distribution,previous studies performed electrocatalyst modifi cation using several universal methods,including composition manipulation,morphology control,surface modifi cation,and defect engineering.Recent studies have revealed that the cathode and electrolytes infl uence the selectivity of CO_(2) RR via pH changes and ionic eff ects,or by directly participating in the reduction pathway as cocatalysts.This review summarizes the state-of-the-art optimization strategies to effi ciently enhance CO_(2) RR selectivity from two main aspects,namely the cathode electrocatalyst and the electrolyte.
基金supported by the National Key Research and Development Program of China(Nos.2018YFA0208600,2018YFA0704502)NSFC(Nos.21871263,22071245,22033008)Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China(No.2021ZZ103)。
文摘Porous crystalline metal-organic frameworks(MOFs)and covalent organic frameworks(COFs)are promising platforms for electrocatalytic reduction of CO_(2)(CO_(2)RR)due to their large CO_(2)adsorption uptakes and periodically arranged single active sites.However,the applications in CO_(2)RR of the traditional MOFs and COFs are greatly limited by their low electron conductivity.In recent years,numerous types of MOFs and COFs with high intrinsic conductivity have been rationally designed and successfully constructed,and some of them have been applied in CO_(2)RR.In this review,the applications of conductive MOFs and COFs in CO_(2)RR have been summarized.The conductive MOFs and COFs can be categorized according to the methods,in which the conductivity is enhanced,such as constructing fullyπ-conjugated backbones,donor-acceptor heterojunction,enhancing theπ-πstacking interactions between organic moieties and/or the introduction of guest molecules.
基金supported by the Young Scientists Fund of the National Natural Science Foundation of China(No.22101182)Guangdong Basic and Applied Basic Research Foundation(No.2020A1515110499)+2 种基金Shenzhen Science and Technology Program(No.JCYJ20210324095202006),Shenzhen University Young Teacher Research Project(No.000002110713)the Shccig-Qinling Program(No.2021JLM-27)the Jinchuan Group Co.Ltd.Chemical Environmental Protection Industry Joint Laboratory(No.20-0837).
文摘To improve the atomic utilization of metals and reduce the cost of industrialization,the one-step total monoatomization of macroscopic bulk metals,as opposed to nanoscale metals,is effective.In this study,we used a thermal diffusion method to directly convert commercial centimeter-scale Ni foam to porous Ni single-atom-loaded carbon nanotubes(CNTs).As expected,owing to the coating of single-atom on porous,highly conductive CNT carriers,Ni single-atom electrocatalysts(Ni-SACs)exhibit extremely high activity and selectivity in CO_(2)electroreduction(CO_(2)RR),yielding a current density of>350 mA/cm^(2),a selectivity for CO of>91%under a flow cell configuration using a 1 M potassium chloride(KCl)electrolyte.Based on the superior activity of the Ni-SACs electrocatalyst,an integrated gas-phase electrochemical zero-gap reactor was introduced to generate a significant amount of CO current for potential practical applications.The overall current can be increased to 800 mA,while maintaining CO Faradaic efficiencies(FEs)at above 90%per unit cell.Our findings and insights on the active site transformation mechanism for macroscopic bulk Ni foam conversion into single atoms can inform the design of highly active single-atom catalysts used in industrial CO_(2)RR systems.
基金supported by the National Key Research and Development Program of China(No.2021YFA1500402)the National Natural Science Foundation of China(NSFC)(Nos.21725101,21871244,and 22001242)+3 种基金International Partnership Program of Chinese Academy of Sciences(CAS)(No.211134KYSB20190109)Collaborative Innovation Program of Hefei Science Center,CAS(No.2020HSC-CIP005)the Fundamental Research Funds for the Central Universities(Nos.WK2060000038 and WK2060000040)We thank the XAFS measurements from 1W1B station at BSRF.
文摘Single-atom catalysts(SACs),with the utmost atom utilization,have attracted extensive interests for various catalytic applications.The coordination environment of SACs has been recognized to play a vital role in catalysis while their precise regulation at atomic level remains an immense challenge.Herein,a post metal halide modification(PMHM)strategy has been developed to construct Ni-N4 sites with axially coordinated halogen atoms,named Ni1-N-C(X)(X=CI,Br,and I),on pre-synthetic nitrogen-doped carbon derived from metal-organic frameworks.The axial halogen atoms with distinct electronegativity can break the symmetric charge distribution of planar Ni-N4 sites and regulate the electronic states of central Ni atoms in Ni1-N-C(X)(X=Cl,Br,and I).Significantly,the Ni1-N-C(CI)catalyst,decorated with the most electronegative Cl atoms,exhibits Faradaic efficiency of CO up to 94.7%in electrocatalytic CO_(2) reduction,outperforming Ni1-N-C(Br)and Ni1-N-C(I)catalysts.Moreover,Ni1-N-C(CI)also presents superb performance in Zn-CO_(2) battery with ultrahigh CO selectivity and great durability.Theoretical calculations reveal that the axially coordinated Cl atom remarkably facilitates*COOH intermediate formation on single-atom Ni sites,thereby boosting the CO_(2) reduction performance of Ni1-N-C(CI).This work offers a facile strategy to tailor the axial coordination environments of SACs at atomic level and manifests the crucial role of axial coordination microenvironments in catalysis.
文摘Cu-based catalysts are the most promising candidates for electrochemical CO_(2)reduction(CO_(2)RR)to multi-carbon(C_(2))products.Optimizing the C-C coupling process,the rate-determining step for C_(2)product generation,is an important strategy to improve the production and selectivity of the C_(2)products.In this study,we determined that the local electric field can promote the C-C coupling reaction and enhance CO_(2)electroreduction to C_(2)products.First,finite-element simulations indicated that the high curvature of the Cu nanoneedles results in a large local electric field on their tips.Density functional theory(DFT)calculations proved that a large electric field can promote C-C coupling.Motivated by this prediction,we prepared a series of Cu catalysts with different curvatures.The Cu nanoneedles(NNs)exhibited the largest number of curvatures,followed by the Cu nanorods(NRs),and Cu nanoparticles(NPs).The Cu NNs contained the highest concentration of adsorbed K+,which resulted in the highest local electric field on the needles.CO adsorption sensor tests indicated that the Cu NNs exhibited the strongest CO adsorption ability,and in-situ Fourier-transform infrared spectroscopy(FTIR)showed the strongest*COCO and*CO signals for the Cu NNs.These experimental results demonstrate that high-curvature nanoneedles can induce a large local electric field,thus promoting C-C coupling.As a result,the Cu NNs show a maximum FEC_(2)of 44%for CO_(2)RR at a low potential(-0.6 V vs.RHE),which is approximately 2.2 times that of the Cu NPs.This work provides an effective strategy for enhancing the production of multi-carbon products during CO_(2)RR.
基金supported by the National Key R&D Program of China(2021YFA1501503)the National Natural Science Foundation of China(Nos.22002155,22125205,92045302)+3 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB17020200)the CAS Youth Innovation Promotion(Y201938)the Natural Science Foundation of Liaoning Province(2021-MS-022)the High-Level Talents Innovation Project of Dalian City(2020RQ038).
文摘Catalytic conversion of CO_(2)into chemicals and fuels is a viable method to reduce carbon emissions and achieve carbon neutrality.Through thermal catalysis,electrocatalysis,and photo(electro)catalysis,CO_(2)can be converted into a wide range of valuable products,including CO,formic acid,methanol,methane,ethanol,acetic acid,propanol,light olefi ns,aromatics,and gasoline,as well as fi ne chemicals.In this mini-review,we summarize the recent progress in heterogeneous catalysis for CO_(2)conversion into chemicals and fuels and highlight some representative studies of diff erent conversion routes.The structure-performance correlations of typical catalytic materials used for the CO_(2)conversion reactions have been revealed by combining advanced in situ/operando spectroscopy and microscopy characterizations and density functional theory cal-culations.Catalytic selectivity toward a single CO_(2)reduction product/fraction should be further improved at an industrially relevant CO_(2)conversion rate with considerable stability in the future.
基金supported by the National Basic Research Program of China(Grant 2018YFA0702001)the National Natural Science Foundation of China(Grants 22225901,21975237 and 51702312)+5 种基金the Fundamental Research Funds for the Central Universities(Grant WK2340000101)the USTC Research Funds of the Double First-Class Initiative(Grant YD2340002007 and YD9990002017)the Open Funds of the State Key Laboratory of Rare Earth Resource Utilization(Grant RERU2022007)the China Postdoctoral Science Foundation(Grants 2023M733371,2022M723032,and 2023T160617)the Natural Science Foundation Youth Project of Anhui Province(2308085QB37)the China National Postdoctoral Program for Innovative Talents(BX2023341).
文摘Copper(Cu)is considered to be the most effective catalyst for electrochemical conversion of carbon dioxide(CO_(2))into value-added hydrocarbons,but its stability still faces considerable challenge.Here,we report the poisoning effect of carbon deposition during CO_(2)reduction on the active sites of Cu electrodea critical deactivation factor that is often overlooked.We find that,*C,an intermediate toward methane formation,could desorb on the electrode surface to form carbon species.We reveal a strong correlation between the formation of methane and the carbon deposition,and the reaction conditions favoring methane production result in more carbon deposition.The deposited carbon blocks the active sites and consequently causes rapid deterioration of the catalytic performance.We further demonstrate that the carbon deposition can be mitigated by increasing the roughness of the electrode and increasing the pH of the electrolyte.This work offers a new guidance for designing more stable catalysts for CO_(2)reduction.
基金National Natural Science Foundation of China,Grant/Award Number:21902009National Key Research and Development Project,Grant/Award Numbers:2018YFB1502401,2018YFA0702002+2 种基金Royal Society and the Newton Fund through the Newton Advanced Fellowship Award,Grant/Award Number:NAF\R1\191294Program for Changjiang Scholars and Innovation Research Team in the University,Grant/Award Number:IRT1205Fundamental Research Funds for the Central Universities,and the longterm subsidy mechanism from the Ministry of Finance and the Ministry of Education of PRC。
文摘Electroreduction of carbon dioxide into fuels and feedstocks with renewable energy is an attractive route to mitigate carbon emission and solve energy crisis.However,how to improve the selectivity of high‐value multicarbon products is still challenging.Here,we demonstrate that the high‐index crystalline surface of copper could be designed and obtained through a simple square‐wave potential treatment on copper nanowires,which is beneficial to improve the selectivity of multi‐carbon products,especially the reaction route towards ethylene.The Faradaic efficiency of C_(2+)products can reach nearly 60%,and hydrogen can be suppressed to below 20%.Density functional theory(DFT)calculations reveal that(311)high‐index facet can activate CO_(2) effectively and promote adsorption of the*COCOH intermediate on copper for ethylene formation,therefore improves the selectivity of ethylene and inhibits the competing hydrogen evolution reaction.This method can be extended to the design of other catalytic systems and has inspirations for other electrochemical catalytic reactions.
基金supported by the National Natural Science Foundation of China(22205205)Zhejiang Provincial Natural Science Foundation of China(No.LQ22B030008)the Science Foundation of Zhejiang Sci-Tech University(ZSTU)under Grant(Nos.21062337-Y,22062312-Y).
文摘Regulating the electronic structure of Bi-based materials by alloying engineering is promising to promote the electrocatalytic activity,but it remains some challenges to be solved.In this study,a facile electrochemical co-deposition strategy is developed to synthesize the bimetallic Bi_(9)Cu_(1) alloy nanosheet on carbon cloth(Bi_(9)Cu_(1)/CC),which represents a novel self-supporting electrode for the electrocatalytic carbon dioxide(CO_(2))reduction reaction(CO_(2)RR).The Bi_(9)Cu_(1)/CC catalyst has achieved a remarkable catalytic performance with high Faradaic efficiencies(FE)of over 90%for formate at wide potentials from-0.7 to-1.2 V vs.reversible hydrogen electrode(RHE).Moreover,the reversible Zn-CO_(2) battery can be driven by Bi_(9)Cu_(1)/CC cathode with a largest power density of 1.4 mW·cm^(-2),and superior operating stability.The systematic characterizations and electrochemical results confirm that the improved catalytic active sites,the enhanced mass/charge transport and the optimal reaction kinetics of Bi nanosheet are realized for CO_(2)RR by Cu alloying.In situ attenuated total reflection infrared(ATR-IR)result confirms the bimetallic Bi-Cu active sites prefer to follow the^(*)OCHO conversion pathway.The density functional theory(DFT)calculations suggest that the Cu alloying contributes to the increased density of states near the Fermi surface of Bi and the optimized adsorption of^(*)OCHO intermediates on the Bi sites,resulting in the excellent catalytic performance.
基金the support from the National Natural Science Foundation of China (Nos.21773314, 21720102007,21821003 and 21890382)the Guangdong Natural Science Funds for Distinguished Young Scholar (No. 2019B151502017)+3 种基金the Tip-top Youth Talents of Guangdong special support program (No.20173100042150021)Science and Technology Planning Project of Guangzhou (No.201707010168)the General Financial Grant from the China Postdoctoral Science Foundation (No.2019M662809)Local Innovative and Research Teams Project of Guangdong Peal River Talents Program (No.2017BT01C161)。
文摘Reliable technologies for CO_(2) capture and conversion(C3) are of vital importance for the establishment of a sustainable society.Metal-organic framework(MOF) composites have shown their compelling potentials for C3 due to the plentiful reticular chemistry of MOF structures and the synergistic catalysis between MOFs and the functional guests.This review focuses on the syntheses and catalytic applications towards C3 of MOF composites,which is divided into three sections.The first section gives a brief introduction about synthetic strategies of MOF composites.The second section discusses the recent progress of MOF composites in C3,including CO_(2) chemical fixation,hydrogenation,photoreduction,electro reduction and photoelectro reduction.The third section summarizes the challenges and future prospects of MOF composites for C3.We hope that this review cannot only provide an inspiration for the rational design of MOF composites for C3,but also stimulate more and more research works in this emerging area.
基金supported by the National Natural Science Foundation of China(grant nos.22033009,22121002,and 22238011).
文摘Electrochemical reduction of CO_(2) to formic acid(HCOOH)is an important route for storing renewable energy and achieving carbon neutrality.Herein,we propose the continuous production of HCOOH solution from electrocatalytic CO_(2) reduction using highly mesoporous bismuth oxide(Bi_(2)O_(3))nanosheets as an electrocatalyst and membrane electrode assembly with solid-state electrolyte as an electrolyzer.Precisely,0.1 M of HCOOH solution could be produced continuously at a current density of -56 mA cm^(-2) for at least 43 h.The underlying mechanism for the high performance of the electrocatalytic system was investigated by experimental studies and theoretical calculations.
基金supported by the Australian Research Council through the Discovery Project programs (FL170100154,FT200100062,DP220102596 and DP190103472)the support from the Australian Government through the Research Training Program Scholarships。
