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 Li-ions. Specially, the zinc nanodots derived from the carbothermal reaction of ZnCl2 at high temperature can interact with sulfur/polysulfides by strong chemisorption. In addition, the zinc nanodots can also facilitate the conversion reaction between Li2Sx (2 < x < 8) and Li2S/Li2S2. Therefore, Zn@NCFs/S cathode presents high sulfur utility and large capacity. (C) 2021 Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences. Published by Elsevier B.V. All rights reserved.