Constructing High‐Content Sb Atomic Clusters and Robust Sb─O─C Bond in Sb/C Composites for Ultrahigh Rate and Long‐Term Sodium Storage

Abstract

AbstractConstructing Sb atomic clusters with obvious size effect in Sb/C composites has great potential for boosting electrochemical reactivity toward ultrahigh rate and long‐term sodium storage. However, how to balance the contradiction between ultra‐small size of Sb atomic clusters and high loading in a specific Sb/C composite is an unprecedented challenge. Here, a facile in situ vaporization‐reduction strategy is presented for preparing Sb atomic clusters@N, S co‐doped carbon networks (Sb ACs@NSC). Featuring the high content of Sb atomic clusters (45.30 wt%, ICP) with superior electrochemical activity, robust Sb─O─C bond and N, S co‐doped conductive carbon matrix, the Sb ACs@NSC electrode possessed ultrafast electrochemical kinetics and impressive long‐term cycling stability for providing unprecedented rate capability of 245.7 mAh g−1 at ultrahigh rate of 80 A g−1 and maintaining highlighted capacity of 306.7 mAh g−1 after 1000 cycles under 10 A g−1, outperforming all reported Sb‐based materials for SIBs. The DFT calculations further revealed that the Sb─O─C bond and N, S co‐doped carbon matrix are beneficial for stable adsorption capabilities and fast electrochemical kinetics of Na+. The designing compromised dense Sb atomic clusters and powerful interface bond will light on developing advanced atomic materials for energy storage and conversion.