Hierarchically porous nitrogen-doped carbon foams decorated with zinc nanodots as high-performance sulfur hosts for lithium-sulfur battery

To prevent polysulfides from dissolution into electrolyte,we propose a novel and simple approach to nitrogen-doped carbon foams which contain hierarchically porous structure and are decorated with zinc nanodots through one-pot carbonization and activation process.These carbon foams,which serve as hosts for sulfur in lithium battery,can provide a conducting network and shorter diffusion length for Liions.Specially,the zinc nanodots derived from the carbothermal reaction of ZnCl_(2) at high temperature can interact with sulfur/polysulfides by strong chemisorption.In addition,the zinc nanodots can also facilitate the conversion reaction between Li_(2)S_(x)(2<x<8)and Li_(2)S/Li_(2)S_(2).Therefore,Zn@NCFs/S cathode presents high sulfur utility and large capacity.