Lithium–sulfur(Li–S)batteries have been becoming a new generation of secondary batteries due to their high theoretical energy density.Regarding sulfur-based cathodes,they not only help to strengthen the utilization ...Lithium–sulfur(Li–S)batteries have been becoming a new generation of secondary batteries due to their high theoretical energy density.Regarding sulfur-based cathodes,they not only help to strengthen the utilization of sulfur,but also effectively immobilize polysulfides to alleviate their dissolution and diffusion.Herein,a new confinement strategy is initiated by a distinctive sulfur scaffold,namely nitrogen doped gra phitic ladder-structured carbon nanotubes(NGLCNTs)loaded with appropriate amount of metallic cobalt nanoparticles.Benefiting from both the unique graphitic ladder-structure and metallic cobalt nano particles in the nitrogen doped carbon nanotubes,the NGLCNTs host not only promotes ion transfer and electron transmission during the redox reactions from higher-order polysulfides to Li_(2)S_(2)/Li_(2)S,but also effciently restricts the outward diffusion and dissolution of polysulfides as well as benefits the nucleation and growth of Li_(2)S.As a result,the NGLCNTs/S cathode has successfully overcome the crucial issues,and it exhibits greatly enhanced electrochemical performances with excellent rate capabilities of up to 8C and long term cycling life of over 500 cycles.展开更多
基金supports pro vided by the National Natural Science Foundation of China(21971145)the Taishan Scholar Project Foundation of Shandong Province(ts20190908 and ts201511004)+1 种基金the Natural Science Foundation of Shandong Province(ZR2019MB024)the Young Scholars Program of Shandong University(2017WLJH15).
文摘Lithium–sulfur(Li–S)batteries have been becoming a new generation of secondary batteries due to their high theoretical energy density.Regarding sulfur-based cathodes,they not only help to strengthen the utilization of sulfur,but also effectively immobilize polysulfides to alleviate their dissolution and diffusion.Herein,a new confinement strategy is initiated by a distinctive sulfur scaffold,namely nitrogen doped gra phitic ladder-structured carbon nanotubes(NGLCNTs)loaded with appropriate amount of metallic cobalt nanoparticles.Benefiting from both the unique graphitic ladder-structure and metallic cobalt nano particles in the nitrogen doped carbon nanotubes,the NGLCNTs host not only promotes ion transfer and electron transmission during the redox reactions from higher-order polysulfides to Li_(2)S_(2)/Li_(2)S,but also effciently restricts the outward diffusion and dissolution of polysulfides as well as benefits the nucleation and growth of Li_(2)S.As a result,the NGLCNTs/S cathode has successfully overcome the crucial issues,and it exhibits greatly enhanced electrochemical performances with excellent rate capabilities of up to 8C and long term cycling life of over 500 cycles.
