Rechargeable zinc-air batteries(ZAB)with a high theoretical energy density of 1086 Wh kg^(-1),have received tremendous research attention.However,the practical application of ZABs is still limited by high polarization...Rechargeable zinc-air batteries(ZAB)with a high theoretical energy density of 1086 Wh kg^(-1),have received tremendous research attention.However,the practical application of ZABs is still limited by high polarization and poor energy efficiency(low power density)due to the sluggish 4 electrons(e^(-))/oxygen(O_(2))kinetics over the air electrode.Here,a noble-metal-free Fe Nx C electrocatalyst is developed via a onepot approach,which provides a high density of the oxygen reduction reaction(ORR)active site and facilitates the ORR kinetics.Accordingly,the as-assembled Zn-air battery displayed a low charge–discharge voltage gap of 0.71 V at 10 m A cm^(-2),a remarkable peak power density as high as 181.2 m W cm^(-2),as well as the long-term durability for hundreds of hours,among the top level of those reported previously.Our work provides a major boost for the practical application of Zn-air battery in the future.展开更多
The electroreduction of CO_(2)(CO_(2)RR)into value-added chemicals is a sustainable strategy for mitigating global warming and managing the global carbon balance.However,developing an efficient and selective catalyst ...The electroreduction of CO_(2)(CO_(2)RR)into value-added chemicals is a sustainable strategy for mitigating global warming and managing the global carbon balance.However,developing an efficient and selective catalyst is still the central challenge.Here,we developed a simple two-step pyrolysis method to confine low-valent Ni-based nanoparticles within nitrogen-doped carbon(Ni-NC).As a result,such Ni-based nanoparticles can effectively reduce CO_(2)to CO,with a maximum CO Faradaic efficiency(FE)of 98%at an overpotential of 0.8 V,as long as good stability.Experimental and the density functional theory(DFT)calculation results reveal that low-valent Ni plays a key role in activity and selectivity enhancement.This study presents a new understanding of Ni-based CO_(2)RR,and provides a simple,scalable approach to the synthesis of low-valent catalysts towards efficient CO_(2)RR.展开更多
基金financially supported by the Shenzhen Science and Technology Research Grant(JCYJ20200109140416788)the Chemistry and Chemical Engineering Guangdong Laboratory(1922018)+1 种基金the National Key R&D Program of China(2020YFB0704500)the financial support from the China Scholarship Council(CSC)and the Australian Research Council(ARC)through an ARC project(ARC DP160102627 and ARC DP170101467)。
文摘Rechargeable zinc-air batteries(ZAB)with a high theoretical energy density of 1086 Wh kg^(-1),have received tremendous research attention.However,the practical application of ZABs is still limited by high polarization and poor energy efficiency(low power density)due to the sluggish 4 electrons(e^(-))/oxygen(O_(2))kinetics over the air electrode.Here,a noble-metal-free Fe Nx C electrocatalyst is developed via a onepot approach,which provides a high density of the oxygen reduction reaction(ORR)active site and facilitates the ORR kinetics.Accordingly,the as-assembled Zn-air battery displayed a low charge–discharge voltage gap of 0.71 V at 10 m A cm^(-2),a remarkable peak power density as high as 181.2 m W cm^(-2),as well as the long-term durability for hundreds of hours,among the top level of those reported previously.Our work provides a major boost for the practical application of Zn-air battery in the future.
基金the financial support from the Shenzhen Science and Technology Research Grant(No.JCYJ20200109140416788,China)the Chemistry and Chemical Engineering Guangdong Laboratory(No.1922018,China)National Key R&D Program of China(No.2020YFB0704500)。
文摘The electroreduction of CO_(2)(CO_(2)RR)into value-added chemicals is a sustainable strategy for mitigating global warming and managing the global carbon balance.However,developing an efficient and selective catalyst is still the central challenge.Here,we developed a simple two-step pyrolysis method to confine low-valent Ni-based nanoparticles within nitrogen-doped carbon(Ni-NC).As a result,such Ni-based nanoparticles can effectively reduce CO_(2)to CO,with a maximum CO Faradaic efficiency(FE)of 98%at an overpotential of 0.8 V,as long as good stability.Experimental and the density functional theory(DFT)calculation results reveal that low-valent Ni plays a key role in activity and selectivity enhancement.This study presents a new understanding of Ni-based CO_(2)RR,and provides a simple,scalable approach to the synthesis of low-valent catalysts towards efficient CO_(2)RR.
