Insight into Accelerating Polysulfides Redox Kinetics by BN@MXene Heterostructure for Li–S Batteries

作者：Yaochen Song, Pengkai Tang, Yi Wang, Linnan Bi, Liang Qi, Yilin Yao, Yilin Yao, Yuhong Qiu, Liang He, Qingyu Xie, Peng Dong, Yingjie Zhang, Yao Yao, Yao Yao, Jiaxuan Liao, Sizhe Wang · 发表于：Small · 年份：2023 · DOI：10.1002/smll.202302386 · 被引用次数：43 · 研究领域：Advanced Battery Materials and Technologies、Advancements in Battery Materials、MXene and MAX Phase Materials

Abstract Sluggish redox kinetics and shuttle effect of polysulfides hinder the extensive application of the lithium–sulfur batteries (LSBs). Herein a functional heterostructure of boron nitride (BN) and MXene with an alternately layered structure (BN@MXene) is designed as separator interlayer. High efficiency Li + transmission, uniform lithium deposition, strong adsorption, and efficient catalytic conversion activities of lithium polysulfides (LiPSs) realized by this heterostructure are confirmed by experiments and theoretical calculations. The alternately layered structure provides unblocked ion transmission channels and abundant active sites to accelerate the polysulfides redox kinetics with reduced energy barriers of oxidation and reduction reactions. As a result, the LSBs deliver an initial discharge capacity of up to 1273.9 mAh g −1 at 0.2 °C and a low decay of 0.058% per cycle in long‐term cycling up to 700 cycles at 1 °C. This work provides an effective designing strategy to accelerate the polysulfides redox kinetics for advanced Li–S electrochemical system.