Selenium(Se)is a promising cathode material for lithium batteries due to its high volumetric energy density(2528 Wh·L^(-1)).However,its practical application is restricted by rapid capacity fading resulting from ...Selenium(Se)is a promising cathode material for lithium batteries due to its high volumetric energy density(2528 Wh·L^(-1)).However,its practical application is restricted by rapid capacity fading resulting from the shuttle effect and slow reaction kinetics.Herein,a N/Co co-doped three-dimensional porous carbon(Co-NC)is prepared and used as Se host for lithium-selenium batteries(LSeBs).Co-NC displays a high specific surface area of1201 m^(2)·g^(-1)which benefits from N and Co doping.The N and Co not only enhance the electrical conductivity of porous carbon but also possess an adsorption effect on polyselenide.Thus,Se/Co-NC electrode exhibits excellent cycling performance(a stable specific capacity of 480 mAh·g^(-1)after 200 cycles at 1.0C with a much lowcapacity decay of 0.028%per cycle)and outstanding rate performance(a high specific capacity of 414 mAh·g^(-1)at5.0C).This work inspires highly stable Se cathode design for LSeBs.展开更多
基金financially supported by the National Key Research and Development Project(No.2018YFE0124800)the Research Project of Education Department of Jiangxi Province(No.GJJ190310)Natural Science Foundation of Jiangxi Province(No.20212BAB204006)。
文摘Selenium(Se)is a promising cathode material for lithium batteries due to its high volumetric energy density(2528 Wh·L^(-1)).However,its practical application is restricted by rapid capacity fading resulting from the shuttle effect and slow reaction kinetics.Herein,a N/Co co-doped three-dimensional porous carbon(Co-NC)is prepared and used as Se host for lithium-selenium batteries(LSeBs).Co-NC displays a high specific surface area of1201 m^(2)·g^(-1)which benefits from N and Co doping.The N and Co not only enhance the electrical conductivity of porous carbon but also possess an adsorption effect on polyselenide.Thus,Se/Co-NC electrode exhibits excellent cycling performance(a stable specific capacity of 480 mAh·g^(-1)after 200 cycles at 1.0C with a much lowcapacity decay of 0.028%per cycle)and outstanding rate performance(a high specific capacity of 414 mAh·g^(-1)at5.0C).This work inspires highly stable Se cathode design for LSeBs.
