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
Electrochemical CO reduction reaction(CORR) provides a promising approach for producing valuable multicarbon products(C_(2+)), while the low solubility of CO in aqueous solution and high energy barrier of C–C couplin...Electrochemical CO reduction reaction(CORR) provides a promising approach for producing valuable multicarbon products(C_(2+)), while the low solubility of CO in aqueous solution and high energy barrier of C–C coupling as well as the competing hydrogen evolution reaction(HER) largely limit the efficiency for C_(2+)production in CORR. Here we report an overturn on the Faradaic efficiency of CORR from being HER-dominant to C_(2+)formation-dominant over a wide potential window, accompanied by a significant activity enhancement over a Moss-like Cu catalyst via pressuring CO. With the CO pressure rising from 1 to 40 atm, the C_(2+)Faradaic efficiency and partial current density remarkably increase from 22.8%and 18.9 mA cm^(-2)to 89.7% and 116.7 mA cm^(-2), respectively. Experimental and theoretical investigations reveal that high pressure-induced high CO coverage on metallic Cu surface weakens the Cu–C bond via reducing electron transfer from Cu to adsorbed CO and restrains hydrogen adsorption, which significantly facilitates the C–C coupling while suppressing HER on the predominant Cu(111) surface, thereby boosting the CO electroreduction to C_(2+)activity.展开更多
Excess greenhouse gas emissions,primarily carbon dioxide(CO_(2)),have caused major environmental concerns worldwide.The electroreduction of CO_(2)into valuable chemicals using renewable energy is an ecofriendly approa...Excess greenhouse gas emissions,primarily carbon dioxide(CO_(2)),have caused major environmental concerns worldwide.The electroreduction of CO_(2)into valuable chemicals using renewable energy is an ecofriendly approach to achieve carbon neutrality.In this regard,copper(Cu)has attracted considerable attention as the only known metallic catalyst available for converting CO_(2)to high-value multicarbon(C_(2+))products.The production of C_(2+)involves complicated C-C coupling steps and thus imposes high demands on intermediate regulation.In this review,we discuss multiple strategies for modulating intermediates to facilitate C_(2+)formation on Cu-based catalysts.Furthermore,several sophisticated in situ characterization techniques are outlined for elucidating the mechanism of C-C coupling.Lastly,the challenges and future directions of CO_(2)electroreduction to C_(2+)are envisioned.展开更多
Electrochemical reduction of CO_(2)(CO_(2)RR)to form high-energy-density and high-value-added multicarbon products has attracted much attention.Selective reduction of CO_(2)to C^(2+)products face the problems of low r...Electrochemical reduction of CO_(2)(CO_(2)RR)to form high-energy-density and high-value-added multicarbon products has attracted much attention.Selective reduction of CO_(2)to C^(2+)products face the problems of low reaction rate,complex mechanism and low selectivity.Currently,except for a few examples,copper-based catalysts are the only option capable of achieving efficient generation of C^(2+)products.However,the continuous dynamic reconstruction of the catalyst causes great difficulty in understanding the structure-performance relationship of CO_(2)RR.In this review,we first discuss the mechanism of C^(2+)product generation.The structural factors promoting C^(2+)product generation are outlined,and the dynamic evolution of these structural factors is discussed.Furthermore,the effects of electrolyte and electrolysis conditions are reviewed in a vision of dynamic surface.Finally,further exploration of the reconstruction mechanism of Cu-based catalysts and the application of emerging robotic AI chemists are discussed.展开更多
The Cu^(+)/Cu^(0)sites of copper-based catalysts are crucial for enhancing the production of multicarbon(C_(2+))products from electrochemical CO_(2)reduction reaction(eCO_(2)RR).However,the unstable Cu^(+)and insuffic...The Cu^(+)/Cu^(0)sites of copper-based catalysts are crucial for enhancing the production of multicarbon(C_(2+))products from electrochemical CO_(2)reduction reaction(eCO_(2)RR).However,the unstable Cu^(+)and insufficient Cu^(+)/Cu^(0)active sites lead to their limited selectivity and stability for C_(2+)production.Herein,we embedded copper oxide(CuO_(x))particles into porous nitrogen-doped carbon nanofibers(CuO_(x)@PCNF)by pyrolysis of the electrospun fiber film containing ZIF-8 and Cu_(2)O particles.The porous nitrogendoped carbon nanofibers protected and dispersed Cu^(+)species,and its micro porous structure enhanced the interaction between CuO_(x)and reactants during eCO_(2)RR.The obtained CuO_(x)@PCNF created more effective and stable Cu^(+)/Cu^(0)active sites.It showed a high Faradaic efficiency of 62.5%for C_(2+)products in Hcell,which was 2 times higher than that of bare CuO_(x)(~31.1%).Furthermore,it achieved a maximum Faradaic efficiency of 80.7%for C_(2+)products in flow cell.In situ characterization and density functional theory(DFT)calculation confirmed that the N-doped carbon layer protected Cu^(+)from electrochemical reduction and lowered the energy barrier for the dimerization of^(*)CO.Stable and exposed Cu^(+)/Cu^(0)active sites enhanced the enrichment of^(*)CO and promoted the C-C coupling reaction on the catalyst surface,which facilitated the formation of C_(2+)products.展开更多
Electrocatalytic CO_(2)reduction reaction(CO_(2)RR)to produce multicarbon(C_(2+))products over Cubased catalysts represents an ideal approach for renewable energy storage and carbon emissions reduction.The Cu^(0)/Cu^(...Electrocatalytic CO_(2)reduction reaction(CO_(2)RR)to produce multicarbon(C_(2+))products over Cubased catalysts represents an ideal approach for renewable energy storage and carbon emissions reduction.The Cu^(0)/Cu^(δ+)interfaces are widely recognized as crucial sites that promote C-C coupling and enhance the generation of C2+products.However,a major challenge arises from the tendency of Cu^(δ+)active sites within Cu^(0)/Cu^(δ+)interfaces to undergo reduction to Cu^(0)during the CO_(2)RR process,leading to a decline in catalytic performance.Hence,it is crucial to establish durable Cu^(0)/Cu^(δ+)interfaces to enhance the conversion of CO_(2)to C_(2+)products.In this work,an iodine modification strategy is proposed to prepare a stable Cu@CuI composite catalyst with well-maintained Cu^(0)/Cu^(δ+)interfaces through a one-step redox reaction between iodine and copper.The optimized Cu@CuI-3composite catalyst demonstrates an excellent performance in CO_(2)RR,achieving a Faradaic efficiency of 75.7%for C^(2+)products and a partial current density of 288 mA·cm^(-2)at-1.57 V_(RHE)in a flow cell.Operando techniques reveal that a numerous persistent Cu^(δ+)species exist on the surface of the Cu@CuI-X composite catalyst even after CO_(2)RR due to the presence of adsorbed iodine ions,which prevent complete reduction of Cu^(δ+)species to Cu^(0)owing to their high electronegativity.Density functional theory calculations further verify that adsorbed iodine ions on the surface of Cu@CuI-X serve as charge regulators by adjusting local charge density,thereby facilitating the formation of*CHO intermediates from CO_(2)and lowering the energy barriers associated with coupling the*CHO and*CO intermediates during CO_(2)RR.Consequently,this phenomenon enhances the selectivity toward C_(2+)products during electrocatalytic CO_(2)reduction.展开更多
Reducing the size of heterogeneous nanocatalysts is generally conducive to improving their atomic utilization and activities in various catalytic reactions.However,this strategy has proven less effective for Cu-based ...Reducing the size of heterogeneous nanocatalysts is generally conducive to improving their atomic utilization and activities in various catalytic reactions.However,this strategy has proven less effective for Cu-based electrocatalysts for the reduction of CO_(2) to multicarbon(O2+)products,owing to the overly strong binding of intermediates on small-sized(<15 nm)Cu nanoparticles(NPs).Herein,by incorporating pyreny-graphdiyne(Pyr-GDY),we successfully endowed ultrafine(〜2 nm)Cu NPs with a significantly elevated selectivity for CO_(2)-to-C_(2+)conversion.The Pyr-GDY can not only help to relax the overly strong binding between adsorbed H*and CO*intermediates on Cu NPs by tailoring the d-band center of the catalyst,but also stabilize the ultrafine Cu NPs through the high affinity between alkyne moieties and Cu NPs.The resulting Pyr-GDY-Cu composite catalyst gave a Faradic efficiency(FE)for C2+products up to 74%,significantly higher than those of support-free Cu NPs(C2+FE.〜2%),carbon nanotube-supported Cu NPs(CNT-Cu,C_(2+)FE,〜18%),graphene oxide-supported Cu NPs(GO-Cu,C_(2+)FE,〜8%),and other reported ultrafine Cu NPs.Our results demonstrate the critical influence of graphdiyne on the selectivity of Cu-catalyzed CO_(2) electroreduction,and showcase the prospect for ultrafine Cu NPs catalysts to convert CO_(2) into value-added C_(2+)products.展开更多
Electrocatalysis of CO_(2)toward multicarbon(C_(2+))products have multifaceted applications in the energy and chemical industries,offers an attractive route to mitigate carbon emissions and abate the depletion of foss...Electrocatalysis of CO_(2)toward multicarbon(C_(2+))products have multifaceted applications in the energy and chemical industries,offers an attractive route to mitigate carbon emissions and abate the depletion of fossil fuels.However,the productivity of CO_(2)-to-C_(2+)products suffers from a low selectivity and reaction rate owing to the difficulty in C-C coupling and the multiple electronproton transfer steps.Recently,numerous tandem catalysts have been developed to improve the selectivity and formation rate of CO_(2)-to-C_(2+)products via coupled multiple reaction steps,exhibiting high industrial practicability.This review summarized recent progresses in the formation of C_(2+)products from CO_(2)electrolysis on tandem catalysts.In this review,we highlight the cooperative regulation strategy of tandem catalysts formed by introducing different types of new components and reveal the relationships between*CO intermediate mass transport and the selectivity of C_(2+)products.Moreover,theoretical insight into the tandem catalytic mechanisms underlying the enhanced C_(2+)selectivity is also provided.Finally,the remaining challenges and opportunities for the electrocatalytic CO_(2)toward C_(2+)products are discussed.展开更多
As efficient catalysts of electrochemical CO_(2)reduction reaction(CO_(2)RR)towards multicarbon(C_(2+))products,Cu-based catalysts have faced the challenges of increasing the reactive activity and selectivity.Herein,w...As efficient catalysts of electrochemical CO_(2)reduction reaction(CO_(2)RR)towards multicarbon(C_(2+))products,Cu-based catalysts have faced the challenges of increasing the reactive activity and selectivity.Herein,we decorated the surface of Cu nanowires(Cu NWs)with a small amount of Au nanoparticles(Au NPs)by the homo-nucleation method.When the Au to Cu mass ratio is as little as 0.7 to 99.3,the gold-doped copper nanowires(Cu-Au NWs)could effectively improve the selectivity and activity of CO_(2)RR to C_(2+)resultants,with the Faradaic efficiency(FE)from 39.7%(Cu NWs)to 65.3%,the partial current density from 7.0(Cu NWs)to 12.1 mA/cm^(2) under−1.25 V vs.reversible hydrogen electrode(RHE).The enhanced electrocatalytic performance could be attributed to the following three synergetic factors.The addition of Au nanoparticles caused a rougher surface of the catalyst,which allowed for more active sites exposed.Besides,Au sites generated*CO intermediates spilling over into Cu sites with the calculated efficiency of 87.2%,which are necessary for multicarbon production.Meanwhile,the interphase electron transferred from Cu to Au induced the electron-deficient Cu,which favored the adsorption of*CO to further generate multicarbon productions.Our results uncovered the morphology,tandem,electronic effect between Cu NWs and Au NPs facilitated the activity and selectivity of CO_(2)RR to multicarbons.展开更多
The electrochemical CO_(2)reduction reaction(CO_(2)RR)on Cu catalyst holds great promise for converting CO_(2)into valuable multicarbon(C_(2+))compounds,but still suffers poor selectivity due to the sluggish kinetics ...The electrochemical CO_(2)reduction reaction(CO_(2)RR)on Cu catalyst holds great promise for converting CO_(2)into valuable multicarbon(C_(2+))compounds,but still suffers poor selectivity due to the sluggish kinetics of forming carbon–carbon(C–C)bonds.Here we reported a perovskite oxide-derived Cu catalyst with abundant grain boundaries for efficient C–C coupling.These grain boundaries are readily created from the structural reconstruction induced by CO_(2)-assisted La leaching.Using this defective catalyst,we achieved a maximum C_(2+)Faradaic efficiency of 80.3%with partial current density over 400 mA cm−2 in neutral electrolyte in a flow-cell electrolyzer.By combining the structural and spectroscopic investigations,we uncovered that the in-situ generated defective sites trapped by grain boundaries enable favorable CO adsorption and thus promote C–C coupling kinetics for C_(2+)products formation.This work showcases the great potential of perovskite materials for efficient production of valuable multicarbon compounds via CO_(2)RR electrochemistry.展开更多
Cu nanoparticles with different sizes,morphology,and surface structures exhibit distinct activity and selectivity toward CO_(2) reduction reaction,while the reactive sites and reaction mechanisms are very controversia...Cu nanoparticles with different sizes,morphology,and surface structures exhibit distinct activity and selectivity toward CO_(2) reduction reaction,while the reactive sites and reaction mechanisms are very controversial in experiments.In this study,we demonstrate the dynamic structure change of Cu clusters on graphite-like carbon supports plays an important role in the multicarbon production by combining static calculations and ab-initio molecular dynamic simulations.The mobility of Cu clusters on graphite is attributed to the near-degenerate energies of various adsorption configurations,as the interaction between Cu atoms and surface C atoms is weaker than that of Cu-Cu bonds in the tight cluster form.Such structure change of Cu clusters leads to step-like irregular surface structures and appropriate interparticle distances,increasing the selectivity of multicarbon products by reducing the energy barriers of C-C coupling effectively.In contrast,the large ratio of edge and corner sites on Cu clusters is responsible for the increased catalytic activity and selectivity for CO and H_(2) compared with Cu(100)surface,instead of hydrocarbon products like methane and ethylene.The detailed study reveals that the dynamic structure change of the catalysts results in roughened surface morphologies during catalytic reactions and plays an essential role in the selectivity of CO_(2) electro-reduction,which should be paid more attention for studies on the reaction mechanisms.展开更多
Direct electrochemical conversion of CO_(2)to multicarbon products over small-sized Cu nanoparticles(NPs)remains a significant challenge due to the strong binding affinity between^(*)CO and Cu sites.Herein,we develope...Direct electrochemical conversion of CO_(2)to multicarbon products over small-sized Cu nanoparticles(NPs)remains a significant challenge due to the strong binding affinity between^(*)CO and Cu sites.Herein,we developed a facile route to synthesize stable Cu NPs with a size of ca.3.0 nm anchored on zeolitic imidazolate framework-8(ZIF-8)(Cu/ZIF-8)and found that the electronic state of Cu NPs is effectively modulated by ZIF-8,leading to enhanced C_(2+)product selectivity.Due to the electronic interaction between Cu NPs and ZIF-8,the Cu center exhibits an electron-deficient state,resulting in decrease of the d-band center,which lowers the^(*)CO affinity and speeds up asymmetric^(*)CO-^(*)COH coupling.Compared to bare Cu NPs with a low C_(2+)faradaic efficiency(FE)of 18.8%,Cu/ZIF-8 achieves a much higher C_(2+)FE of 61.0%.Moreover,the peak value of C_(2+)partial current density for Cu/ZIF-8 is 279.4 mA cm-2,which exceeds most of the reported Cu-based electrocatalysts.This work provides advanced insights for reasonable design of Cu sites to produce multicarbon products by utilizing a metal-organic framework to stabilize and regulate the binding affinity of intermediates on small-sized Cu NPs.展开更多
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financial support from the National Key R&D Program of China (Nos. 2022YFA1504500, 2022YFA1503100)the National Natural Science Foundation of China (Nos. 21988101, 21890753, 22225204, 92145301, 22002160 and 22272174)+4 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences (No. XDB36030200)the CAS Project for Young Scientists in Basic Research (No. YSBR-028)the Fundamental Research Funds for the Central Universities (No. 20720220008)the Dalian National Lab for Clean Energy (DNL Cooperation Fund 202001)the Innovation Research Fund Project of DICP (No. DICP I202016)。
文摘Electrochemical CO reduction reaction(CORR) provides a promising approach for producing valuable multicarbon products(C_(2+)), while the low solubility of CO in aqueous solution and high energy barrier of C–C coupling as well as the competing hydrogen evolution reaction(HER) largely limit the efficiency for C_(2+)production in CORR. Here we report an overturn on the Faradaic efficiency of CORR from being HER-dominant to C_(2+)formation-dominant over a wide potential window, accompanied by a significant activity enhancement over a Moss-like Cu catalyst via pressuring CO. With the CO pressure rising from 1 to 40 atm, the C_(2+)Faradaic efficiency and partial current density remarkably increase from 22.8%and 18.9 mA cm^(-2)to 89.7% and 116.7 mA cm^(-2), respectively. Experimental and theoretical investigations reveal that high pressure-induced high CO coverage on metallic Cu surface weakens the Cu–C bond via reducing electron transfer from Cu to adsorbed CO and restrains hydrogen adsorption, which significantly facilitates the C–C coupling while suppressing HER on the predominant Cu(111) surface, thereby boosting the CO electroreduction to C_(2+)activity.
基金support of the National Natural Science Foundation of China(Nos.51972223,51932005 and 22109116)the Natural Science Foundation of Tianjin(No.20JCYBJC01550)+1 种基金the Fundamental Research Funds for the Cen-tral Universitiesthe Haihe Laboratory of Sustainable Chemical Transformations.
文摘Excess greenhouse gas emissions,primarily carbon dioxide(CO_(2)),have caused major environmental concerns worldwide.The electroreduction of CO_(2)into valuable chemicals using renewable energy is an ecofriendly approach to achieve carbon neutrality.In this regard,copper(Cu)has attracted considerable attention as the only known metallic catalyst available for converting CO_(2)to high-value multicarbon(C_(2+))products.The production of C_(2+)involves complicated C-C coupling steps and thus imposes high demands on intermediate regulation.In this review,we discuss multiple strategies for modulating intermediates to facilitate C_(2+)formation on Cu-based catalysts.Furthermore,several sophisticated in situ characterization techniques are outlined for elucidating the mechanism of C-C coupling.Lastly,the challenges and future directions of CO_(2)electroreduction to C_(2+)are envisioned.
文摘Electrochemical reduction of CO_(2)(CO_(2)RR)to form high-energy-density and high-value-added multicarbon products has attracted much attention.Selective reduction of CO_(2)to C^(2+)products face the problems of low reaction rate,complex mechanism and low selectivity.Currently,except for a few examples,copper-based catalysts are the only option capable of achieving efficient generation of C^(2+)products.However,the continuous dynamic reconstruction of the catalyst causes great difficulty in understanding the structure-performance relationship of CO_(2)RR.In this review,we first discuss the mechanism of C^(2+)product generation.The structural factors promoting C^(2+)product generation are outlined,and the dynamic evolution of these structural factors is discussed.Furthermore,the effects of electrolyte and electrolysis conditions are reviewed in a vision of dynamic surface.Finally,further exploration of the reconstruction mechanism of Cu-based catalysts and the application of emerging robotic AI chemists are discussed.
基金supported by the National Natural Science Foundation of China(22222601 and 22076019)the Fundamental Research Funds for the Central Universities(DUT23LAB611).
文摘The Cu^(+)/Cu^(0)sites of copper-based catalysts are crucial for enhancing the production of multicarbon(C_(2+))products from electrochemical CO_(2)reduction reaction(eCO_(2)RR).However,the unstable Cu^(+)and insufficient Cu^(+)/Cu^(0)active sites lead to their limited selectivity and stability for C_(2+)production.Herein,we embedded copper oxide(CuO_(x))particles into porous nitrogen-doped carbon nanofibers(CuO_(x)@PCNF)by pyrolysis of the electrospun fiber film containing ZIF-8 and Cu_(2)O particles.The porous nitrogendoped carbon nanofibers protected and dispersed Cu^(+)species,and its micro porous structure enhanced the interaction between CuO_(x)and reactants during eCO_(2)RR.The obtained CuO_(x)@PCNF created more effective and stable Cu^(+)/Cu^(0)active sites.It showed a high Faradaic efficiency of 62.5%for C_(2+)products in Hcell,which was 2 times higher than that of bare CuO_(x)(~31.1%).Furthermore,it achieved a maximum Faradaic efficiency of 80.7%for C_(2+)products in flow cell.In situ characterization and density functional theory(DFT)calculation confirmed that the N-doped carbon layer protected Cu^(+)from electrochemical reduction and lowered the energy barrier for the dimerization of^(*)CO.Stable and exposed Cu^(+)/Cu^(0)active sites enhanced the enrichment of^(*)CO and promoted the C-C coupling reaction on the catalyst surface,which facilitated the formation of C_(2+)products.
基金financially supported by the National Natural Science Foundation of China(Nos.52073009,52272182,51872013 and 52011530190)the Program of the Ministry of Education of China for Introducing Talents of Discipline to Universities(No.B14009)。
文摘Electrocatalytic CO_(2)reduction reaction(CO_(2)RR)to produce multicarbon(C_(2+))products over Cubased catalysts represents an ideal approach for renewable energy storage and carbon emissions reduction.The Cu^(0)/Cu^(δ+)interfaces are widely recognized as crucial sites that promote C-C coupling and enhance the generation of C2+products.However,a major challenge arises from the tendency of Cu^(δ+)active sites within Cu^(0)/Cu^(δ+)interfaces to undergo reduction to Cu^(0)during the CO_(2)RR process,leading to a decline in catalytic performance.Hence,it is crucial to establish durable Cu^(0)/Cu^(δ+)interfaces to enhance the conversion of CO_(2)to C_(2+)products.In this work,an iodine modification strategy is proposed to prepare a stable Cu@CuI composite catalyst with well-maintained Cu^(0)/Cu^(δ+)interfaces through a one-step redox reaction between iodine and copper.The optimized Cu@CuI-3composite catalyst demonstrates an excellent performance in CO_(2)RR,achieving a Faradaic efficiency of 75.7%for C^(2+)products and a partial current density of 288 mA·cm^(-2)at-1.57 V_(RHE)in a flow cell.Operando techniques reveal that a numerous persistent Cu^(δ+)species exist on the surface of the Cu@CuI-X composite catalyst even after CO_(2)RR due to the presence of adsorbed iodine ions,which prevent complete reduction of Cu^(δ+)species to Cu^(0)owing to their high electronegativity.Density functional theory calculations further verify that adsorbed iodine ions on the surface of Cu@CuI-X serve as charge regulators by adjusting local charge density,thereby facilitating the formation of*CHO intermediates from CO_(2)and lowering the energy barriers associated with coupling the*CHO and*CO intermediates during CO_(2)RR.Consequently,this phenomenon enhances the selectivity toward C_(2+)products during electrocatalytic CO_(2)reduction.
基金supported by the National Natural Science Foundation of China(Nos.21702146,21805207,21790052,and 21931007)the National Key Technology R&D Program of China(No.2017YFA0700104)+1 种基金111 Project of China(No.D17003)the Natural Science Foundation of Tianjin(No.19JCQNJC05500).
文摘Reducing the size of heterogeneous nanocatalysts is generally conducive to improving their atomic utilization and activities in various catalytic reactions.However,this strategy has proven less effective for Cu-based electrocatalysts for the reduction of CO_(2) to multicarbon(O2+)products,owing to the overly strong binding of intermediates on small-sized(<15 nm)Cu nanoparticles(NPs).Herein,by incorporating pyreny-graphdiyne(Pyr-GDY),we successfully endowed ultrafine(〜2 nm)Cu NPs with a significantly elevated selectivity for CO_(2)-to-C_(2+)conversion.The Pyr-GDY can not only help to relax the overly strong binding between adsorbed H*and CO*intermediates on Cu NPs by tailoring the d-band center of the catalyst,but also stabilize the ultrafine Cu NPs through the high affinity between alkyne moieties and Cu NPs.The resulting Pyr-GDY-Cu composite catalyst gave a Faradic efficiency(FE)for C2+products up to 74%,significantly higher than those of support-free Cu NPs(C2+FE.〜2%),carbon nanotube-supported Cu NPs(CNT-Cu,C_(2+)FE,〜18%),graphene oxide-supported Cu NPs(GO-Cu,C_(2+)FE,〜8%),and other reported ultrafine Cu NPs.Our results demonstrate the critical influence of graphdiyne on the selectivity of Cu-catalyzed CO_(2) electroreduction,and showcase the prospect for ultrafine Cu NPs catalysts to convert CO_(2) into value-added C_(2+)products.
基金This work was supported by the Fundamental Research Funds for the Central Universities(No.2232021A-02)the National Natural Science Foundation of China(Nos.52122312 and 22209024)+1 种基金Shanghai Pujiang Program(No.22PJ1400200)State Key Laboratory for Modification of Chemical Fibers and Polymer Materials,Donghua University.
文摘Electrocatalysis of CO_(2)toward multicarbon(C_(2+))products have multifaceted applications in the energy and chemical industries,offers an attractive route to mitigate carbon emissions and abate the depletion of fossil fuels.However,the productivity of CO_(2)-to-C_(2+)products suffers from a low selectivity and reaction rate owing to the difficulty in C-C coupling and the multiple electronproton transfer steps.Recently,numerous tandem catalysts have been developed to improve the selectivity and formation rate of CO_(2)-to-C_(2+)products via coupled multiple reaction steps,exhibiting high industrial practicability.This review summarized recent progresses in the formation of C_(2+)products from CO_(2)electrolysis on tandem catalysts.In this review,we highlight the cooperative regulation strategy of tandem catalysts formed by introducing different types of new components and reveal the relationships between*CO intermediate mass transport and the selectivity of C_(2+)products.Moreover,theoretical insight into the tandem catalytic mechanisms underlying the enhanced C_(2+)selectivity is also provided.Finally,the remaining challenges and opportunities for the electrocatalytic CO_(2)toward C_(2+)products are discussed.
基金the National Key Research and Development Program of China(Nos.2017YFA0700103,2018YFA0704502,and 2021YFA1501500)the National Natural Science Foundation of China(NSFC)(No.22033008)Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China(No.2021ZZ103).
文摘As efficient catalysts of electrochemical CO_(2)reduction reaction(CO_(2)RR)towards multicarbon(C_(2+))products,Cu-based catalysts have faced the challenges of increasing the reactive activity and selectivity.Herein,we decorated the surface of Cu nanowires(Cu NWs)with a small amount of Au nanoparticles(Au NPs)by the homo-nucleation method.When the Au to Cu mass ratio is as little as 0.7 to 99.3,the gold-doped copper nanowires(Cu-Au NWs)could effectively improve the selectivity and activity of CO_(2)RR to C_(2+)resultants,with the Faradaic efficiency(FE)from 39.7%(Cu NWs)to 65.3%,the partial current density from 7.0(Cu NWs)to 12.1 mA/cm^(2) under−1.25 V vs.reversible hydrogen electrode(RHE).The enhanced electrocatalytic performance could be attributed to the following three synergetic factors.The addition of Au nanoparticles caused a rougher surface of the catalyst,which allowed for more active sites exposed.Besides,Au sites generated*CO intermediates spilling over into Cu sites with the calculated efficiency of 87.2%,which are necessary for multicarbon production.Meanwhile,the interphase electron transferred from Cu to Au induced the electron-deficient Cu,which favored the adsorption of*CO to further generate multicarbon productions.Our results uncovered the morphology,tandem,electronic effect between Cu NWs and Au NPs facilitated the activity and selectivity of CO_(2)RR to multicarbons.
基金supported by the National Basic Research Program of China(2018YFA0702001)the National Natural Science Foundation of China(21975237 and 51702312)+4 种基金Anhui Provincial Research and Development Program(202004a05020073)the USTC Research Funds of the Double First-Class Initiative(YD2340002007)the Fundamental Research Funds for the Central Universities(WK2340000101)the Technical Talent Promotion Plan(TS2021002)the Recruitment Program of Global Youth Experts.
文摘The electrochemical CO_(2)reduction reaction(CO_(2)RR)on Cu catalyst holds great promise for converting CO_(2)into valuable multicarbon(C_(2+))compounds,but still suffers poor selectivity due to the sluggish kinetics of forming carbon–carbon(C–C)bonds.Here we reported a perovskite oxide-derived Cu catalyst with abundant grain boundaries for efficient C–C coupling.These grain boundaries are readily created from the structural reconstruction induced by CO_(2)-assisted La leaching.Using this defective catalyst,we achieved a maximum C_(2+)Faradaic efficiency of 80.3%with partial current density over 400 mA cm−2 in neutral electrolyte in a flow-cell electrolyzer.By combining the structural and spectroscopic investigations,we uncovered that the in-situ generated defective sites trapped by grain boundaries enable favorable CO adsorption and thus promote C–C coupling kinetics for C_(2+)products formation.This work showcases the great potential of perovskite materials for efficient production of valuable multicarbon compounds via CO_(2)RR electrochemistry.
基金National Natural Science Foundation of China,Grant/Award Numbers:22033002,21525311,21703032Fundamental Research Funds for the Central Universities of China。
文摘Cu nanoparticles with different sizes,morphology,and surface structures exhibit distinct activity and selectivity toward CO_(2) reduction reaction,while the reactive sites and reaction mechanisms are very controversial in experiments.In this study,we demonstrate the dynamic structure change of Cu clusters on graphite-like carbon supports plays an important role in the multicarbon production by combining static calculations and ab-initio molecular dynamic simulations.The mobility of Cu clusters on graphite is attributed to the near-degenerate energies of various adsorption configurations,as the interaction between Cu atoms and surface C atoms is weaker than that of Cu-Cu bonds in the tight cluster form.Such structure change of Cu clusters leads to step-like irregular surface structures and appropriate interparticle distances,increasing the selectivity of multicarbon products by reducing the energy barriers of C-C coupling effectively.In contrast,the large ratio of edge and corner sites on Cu clusters is responsible for the increased catalytic activity and selectivity for CO and H_(2) compared with Cu(100)surface,instead of hydrocarbon products like methane and ethylene.The detailed study reveals that the dynamic structure change of the catalysts results in roughened surface morphologies during catalytic reactions and plays an essential role in the selectivity of CO_(2) electro-reduction,which should be paid more attention for studies on the reaction mechanisms.
基金supported by the National Natural Science Foundation of China(grant nos.22231006,22171131,and 52076045)supported by a project funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions.
文摘Direct electrochemical conversion of CO_(2)to multicarbon products over small-sized Cu nanoparticles(NPs)remains a significant challenge due to the strong binding affinity between^(*)CO and Cu sites.Herein,we developed a facile route to synthesize stable Cu NPs with a size of ca.3.0 nm anchored on zeolitic imidazolate framework-8(ZIF-8)(Cu/ZIF-8)and found that the electronic state of Cu NPs is effectively modulated by ZIF-8,leading to enhanced C_(2+)product selectivity.Due to the electronic interaction between Cu NPs and ZIF-8,the Cu center exhibits an electron-deficient state,resulting in decrease of the d-band center,which lowers the^(*)CO affinity and speeds up asymmetric^(*)CO-^(*)COH coupling.Compared to bare Cu NPs with a low C_(2+)faradaic efficiency(FE)of 18.8%,Cu/ZIF-8 achieves a much higher C_(2+)FE of 61.0%.Moreover,the peak value of C_(2+)partial current density for Cu/ZIF-8 is 279.4 mA cm-2,which exceeds most of the reported Cu-based electrocatalysts.This work provides advanced insights for reasonable design of Cu sites to produce multicarbon products by utilizing a metal-organic framework to stabilize and regulate the binding affinity of intermediates on small-sized Cu NPs.
