A Transmetalation Synthetic Strategy to Engineer Atomically Dispersed MnN<sub>2</sub>O<sub>2</sub> Electrocatalytic Centers Driving High‐Performance LiS Battery
Tengfei Zhang, Dengfeng Luo, Hong Xiao, Xiao Liang, Fanchao Zhang, Huifeng Zhuang, Ming‐De Li, Lirong Zheng, Qiuming Gao
Abstract
Abstract Sluggish sulfur redox reaction (SROR) kinetics accompanying lithium polysulfides (LiPSs) shuttle effect becomes a stumbling block for commercial application of LiS battery. High‐efficient single atom catalysts (SACs) are desired to improve the SROR conversion capability; however, the sparse active sites as well as partial sites encapsulated in bulk‐phase are fatal to the catalytic performance. Herein, high loading (5.02 wt.%) atomically dispersed manganese sites (MnSA) on hollow nitrogen‐doped carbonaceous support (HNC) are realized for the MnSA@HNC SAC by a facile transmetalation synthetic strategy. The thin‐walled hollow structure (≈12 nm) anchoring the unique trans ‐MnN 2 O 2 sites of MnSA@HNC provides a shuttle buffer zone and catalytic conversion site for LiPSs. Both electrochemical measurement and theoretical calculation indicate that the MnSA@HNC with abundant trans ‐MnN 2 O 2 sites have extremely high bidirectional SROR catalytic activity. The assembled LiS battery based on the MnSA@HNC modified separator can deliver a large specific capacity of 1422 mAh g −1 at 0.1 C and stable cycling over 1400 cycles with an ultralow decay rate of 0.033% per cycle at 1 C. More impressively, a flexible pouch cell on account of the MnSA@HNC modified separator may release a high initial specific capacity of 1192 mAh g −1 at 0.1 C and uninterruptedly work after the bending‐unbending processes.