Rechargeable lithium-oxygen batteries(LOBs)have received incremental attention owing to their high energy density and applicability to mobile devices and electric vehicles.However,the lack of robust,low-cost,and envir...Rechargeable lithium-oxygen batteries(LOBs)have received incremental attention owing to their high energy density and applicability to mobile devices and electric vehicles.However,the lack of robust,low-cost,and environmentally benign bifunctional catalysts is a major impediment to the commercial application.The introduction of vacancies is one of the effective strategies to enhance the performance of cathode catalysts for lithium-oxygen batteries,but the preparation is complicated.In this work,needle-like microsphere cathode catalysts of nickel-cobalt oxide containing cationic vacancies are constructed by controlling the annealing temperature.It is demonstrated that the presence of cationic vacancies can modulate the electronic structure of the catalyst,reduce the energy barrier for the oxygen electrode re-action,meanwhile enhance the bifunctional catalytic activity.Impressively,the nickel-cobalt oxide-based LOB with cationic vacancies exhibits large specific capacity(12,205 mAh g^(-1)at 200 mA g^(-1))and good durability.This work provides worthwhile insight into the formation and catalytic enhancement mech-anism of transition metal oxide catalysts with cationic vacancies,and to some extent,the creation of efficient and low-cost oxygen electrocatalysts for LOBs.展开更多
基金This work was financially supported by research projects from Department of Science and Technology of Shandong Province(Nos.2021CXGC010307,2020CXGC010310,ZR2019MEM052,and 2019TSLH0101)The authors acknowledged the assistance of Shandong University Testing and Manufacturing Center for Ad-vanced Materials.H.G.acknowledges the Science and Technol-ogy Project of Hebei Education Department(No.BJK2022068)Hebei Province Introduced Overseas Students Funding Project(No.C20220306).
文摘Rechargeable lithium-oxygen batteries(LOBs)have received incremental attention owing to their high energy density and applicability to mobile devices and electric vehicles.However,the lack of robust,low-cost,and environmentally benign bifunctional catalysts is a major impediment to the commercial application.The introduction of vacancies is one of the effective strategies to enhance the performance of cathode catalysts for lithium-oxygen batteries,but the preparation is complicated.In this work,needle-like microsphere cathode catalysts of nickel-cobalt oxide containing cationic vacancies are constructed by controlling the annealing temperature.It is demonstrated that the presence of cationic vacancies can modulate the electronic structure of the catalyst,reduce the energy barrier for the oxygen electrode re-action,meanwhile enhance the bifunctional catalytic activity.Impressively,the nickel-cobalt oxide-based LOB with cationic vacancies exhibits large specific capacity(12,205 mAh g^(-1)at 200 mA g^(-1))and good durability.This work provides worthwhile insight into the formation and catalytic enhancement mech-anism of transition metal oxide catalysts with cationic vacancies,and to some extent,the creation of efficient and low-cost oxygen electrocatalysts for LOBs.
