Key Words:LITHIUM; BATTERIES; KINETICS; SB2S3
Abstract:Low cost and high energy density lithium-sulfur batteries show great promise for powering next-generation energy storage system. However, the practical application is greatly hindered by the poor cathode conductivity and the shuttle effect of soluble lithium polysulfides. Herein, a leaf-like nanosheets composing of highly dispersed Sb2S3 nanodots embedded in highly nitrogen (18.9%) and sulfur dual-doped porous carbon skeleton (NSCNLs@Sb2S3) is designed for efficient immobilization and catalysis of polysulfides conversion by a facile approach. The conductive carbon matrix effectively enhances the conductivity. Nitrogen/sulfur doping species and Sb2S3 nanodots provide abundant stable active sites to anchor lithium polysulfides. Moreover, a series of fundamental experiments reveal that the Sb2S3 nanodots can boost the redox reaction kinetics and guide the polysulfide to uniformly deposit on carbon matrixes, leading to a stable electrode structure. Benefiting from the unique design of the structure and rational componential selection, the S-NSCNLs@Sb2S3 electrodes deliver a stable capacity after 800 cycles with a capacity fade rate of 0.029% per cycle at 1.0 C and an excellent rate capacity of 567 mAh g-1 at 4.0 C. This present work with facile synthetic process may provide a new sight for the designing and practical application of carbon-based sulfur storage materials.
Volume:420
Issue:
Translation or Not:no