Nano Sn2S3 Embedded in Nitrogenous‐Carbon Compounds for Long‐Life and High‐Rate Cycling Sodium‐Ion Batteries

Abstract Metallic tin (Sn) compounds are viewed as promising candidates for sodium‐ion batteries (SIB) anode materials yet suffer from large volume expansion and limited electrode kinetics. Manufacturing rational structure is a crucial factor to achieve high‐efficiency sodium storage for SIBs. In this study, nano Sn 2 S 3 embedded in nitrogenous‐carbon compounds (nano‐Sn 2 S 3 /C) was designed for SIB anode materials via a facile three‐step strategy: precipitation, heat treatment and vulcanization with no templating agent. Density functional theory calculations suggested that Sn 2 S 3 displayed a low Na + diffusion energy barrier and the Sn−S bonds could be rebuilt during the sodiation/de‐sodiation process. Notably, electrochemical measurements coupled with ex‐situ X‐ray diffraction and ex‐situ transmission electron microscopy were proposed to reveal the underlying Na + storage mechanisms. Sn 2 S 3 acted as a high‐capacity composition, while the porous nitrogenous‐carbon matrix served as a rigid‐conductive frame to accommodate the volume expansion and prevented the aggregation of nano Sn 2 S 3 . The rationally generated architectures benefited greatly in rate capacity and structural stability. As expected, the as‐prepared nano Sn 2 S 3 /C exhibited remarkable rate capabilities with a specific capacity of 603 and 160 mAh g −1 under typical conditions at 0.2 and 4 A g −1 , respectively. This work may trigger new enthusiasm for engineering high‐performance SIB anode materials.