High-temperature CO_(2)electrolysis via solid oxide electrolysis cells(CO_(2)-SOECs)has drawn special attention due to the high energy convention efficiency,fast electrode kinetics,and great potential in carbon cyclin...High-temperature CO_(2)electrolysis via solid oxide electrolysis cells(CO_(2)-SOECs)has drawn special attention due to the high energy convention efficiency,fast electrode kinetics,and great potential in carbon cycling.However,the development of cathode materials with high catalytic activity and chemical stability for pure CO_(2)electrolysis is still a great challenge.In this work,A-site cation deficient dual-phase material,namely(Pr_(0.4)Ca_(0.6))_(x)Fe_(0.8)Ni_(0.2)O_(3-δ)(PCFN,x=1,0.95,and 0.9),has been designed as the fuel electrode for a pure CO_(2)-SOEC,which presents superior electrochemical performance.Among all these compositions,(Pr_(0.4)Ca_(0.6))_(0.95)Fe_(0.8)Ni_(0.2)O_(3-δ)(PCFN95)exhibited the lowest polarization resistance of 0.458Ωcm^(2)at open-circuit voltage and 800℃.The application of PCFN95 as the cathode in a single cell yields an impressive electrolysis current density of 1.76 A cm^(-2)at 1.5 V and 800℃,which is 76%higher than that of single cells with stoichiometric Pr_(0.4)Ca_(0.6)Fe_(0.8)Ni_(0.2)O_(3-δ)(PCFN100)cathode.The effects of A-site deficiency on materials'phase structure and physicochemical properties are also systematically investigated.Such an enhancement in electrochemical performance is attributed to the promotion of effective CO_(2)adsorption,as well as the improved electrode kinetics resulting from the A-site deficiency.展开更多
Solid-oxide fuel cells(SOFCs)offer great promise for producing electricity using a wide variety of fuels such as natural gas,coal gas and gasified carbonaceous solids;however,conventional nickel-based anodes face grea...Solid-oxide fuel cells(SOFCs)offer great promise for producing electricity using a wide variety of fuels such as natural gas,coal gas and gasified carbonaceous solids;however,conventional nickel-based anodes face great challenges due to contaminants in readily available fuels,especially sulphur-containing compounds.Thus,the development of new anode materials that can suppress sulphur poisoning is crucial to the realization of fuel-flexible and cost-effective SOFCs.In this work,La_(0.1)Sr_(1.9)Fe_(1.4)Ni_(0.1)Mo_(0.5)O_(6-δ)(LSFNM)and Pr_(0.1)Sr_(1.9)Fe_(1.4)Ni_(0.1)Mo_(0.5)O_(6-δ)(PSFNM)materials have been synthesized using a sol-gel method in air and investigated as anode mater-ials for SOFCs.Metallic nanoparticle-decorated ceramic anodes were obtained by the reduction of LSFNM and PSFNM in H_(2)at 850℃,forming a Ruddlesden-Popper oxide with exsolved FeNi3 bimetallic nanoparticles.The electrochemical performance of the Sr_(2)Fe_(1.4)Ni_(0.1)Mo_(0.5)O_(6-δ)ceramic anode was greatly enhanced by La doping of A-sites,resulting in a 44%decrease in the polarization resistance in reducing atmosphere.The maximum power densities of Sr-and Mg-doped LaGaO_(3)(LSGM)(300μm)electrolyte-supported single cells with LSFNM as the anode reached 1.371 W cm^(-2)in H_(2)and 1.306 W cm^(-2)in 50 ppm H_(2)S-H_(2)at 850℃.Meanwhile,PSFNM showed improved sulphur tolerance,which could be fully recovered after six cycles from H_(2)to 50 ppm H_(2)S-H_(2)operation.This study indicates that LSFNM and PSFNM are promising high-performance anodes for SOFCs.展开更多
基金supported by the U.S.Department of Energy’s Office of Energy Efficiency and Renewable Energy(EERE)under the Industrial Efficiency&Decarbonization Office award number[DE-EE0009427]the funding support by the U.S.Department of Energy(USDOE),Office of Energy Efficiency and Renewable Energy(EERE),Advanced Manufacturing Office(AMO),under DOE Idaho Operations Office under Contract No.DEAC07-05ID14517
文摘High-temperature CO_(2)electrolysis via solid oxide electrolysis cells(CO_(2)-SOECs)has drawn special attention due to the high energy convention efficiency,fast electrode kinetics,and great potential in carbon cycling.However,the development of cathode materials with high catalytic activity and chemical stability for pure CO_(2)electrolysis is still a great challenge.In this work,A-site cation deficient dual-phase material,namely(Pr_(0.4)Ca_(0.6))_(x)Fe_(0.8)Ni_(0.2)O_(3-δ)(PCFN,x=1,0.95,and 0.9),has been designed as the fuel electrode for a pure CO_(2)-SOEC,which presents superior electrochemical performance.Among all these compositions,(Pr_(0.4)Ca_(0.6))_(0.95)Fe_(0.8)Ni_(0.2)O_(3-δ)(PCFN95)exhibited the lowest polarization resistance of 0.458Ωcm^(2)at open-circuit voltage and 800℃.The application of PCFN95 as the cathode in a single cell yields an impressive electrolysis current density of 1.76 A cm^(-2)at 1.5 V and 800℃,which is 76%higher than that of single cells with stoichiometric Pr_(0.4)Ca_(0.6)Fe_(0.8)Ni_(0.2)O_(3-δ)(PCFN100)cathode.The effects of A-site deficiency on materials'phase structure and physicochemical properties are also systematically investigated.Such an enhancement in electrochemical performance is attributed to the promotion of effective CO_(2)adsorption,as well as the improved electrode kinetics resulting from the A-site deficiency.
基金supported by the US National Science Foundation (DMR-1832809)Idaho National Laboratory,Laboratory Directed Research&Development program under the Department of Energy Idaho Operations Office (DE-AC07-051D14517).
文摘Solid-oxide fuel cells(SOFCs)offer great promise for producing electricity using a wide variety of fuels such as natural gas,coal gas and gasified carbonaceous solids;however,conventional nickel-based anodes face great challenges due to contaminants in readily available fuels,especially sulphur-containing compounds.Thus,the development of new anode materials that can suppress sulphur poisoning is crucial to the realization of fuel-flexible and cost-effective SOFCs.In this work,La_(0.1)Sr_(1.9)Fe_(1.4)Ni_(0.1)Mo_(0.5)O_(6-δ)(LSFNM)and Pr_(0.1)Sr_(1.9)Fe_(1.4)Ni_(0.1)Mo_(0.5)O_(6-δ)(PSFNM)materials have been synthesized using a sol-gel method in air and investigated as anode mater-ials for SOFCs.Metallic nanoparticle-decorated ceramic anodes were obtained by the reduction of LSFNM and PSFNM in H_(2)at 850℃,forming a Ruddlesden-Popper oxide with exsolved FeNi3 bimetallic nanoparticles.The electrochemical performance of the Sr_(2)Fe_(1.4)Ni_(0.1)Mo_(0.5)O_(6-δ)ceramic anode was greatly enhanced by La doping of A-sites,resulting in a 44%decrease in the polarization resistance in reducing atmosphere.The maximum power densities of Sr-and Mg-doped LaGaO_(3)(LSGM)(300μm)electrolyte-supported single cells with LSFNM as the anode reached 1.371 W cm^(-2)in H_(2)and 1.306 W cm^(-2)in 50 ppm H_(2)S-H_(2)at 850℃.Meanwhile,PSFNM showed improved sulphur tolerance,which could be fully recovered after six cycles from H_(2)to 50 ppm H_(2)S-H_(2)operation.This study indicates that LSFNM and PSFNM are promising high-performance anodes for SOFCs.
