Co/CoS 2 Heterojunction Embedded in N, S‐Doped Hollow Nanocage for Enhanced Polysulfides Conversion in High‐Performance Lithium–Sulfur Batteries

作者：Zheng Ming, Junzhe Zhao, Wei Wu, Runzhe Chen, Suhao Chen, Niancai Cheng · 发表于：Small · 年份：2023 · DOI：10.1002/smll.202303192 · 被引用次数：50 · 研究领域：Advanced Battery Materials and Technologies、Polyoxometalates: Synthesis and Applications、Conducting polymers and applications

Abstract Modulating the electronic configuration of the substrate to achieve the optimal chemisorption toward polysulfides (LiPSs) for boosting polysulfide conversion is a promising way to the efficient Li–S batteries but filled with challenges. Herein, a Co/CoS 2 heterostructure is elaborately built to tuning d‐orbital electronic structure of CoS 2 for a high‐performance electrocatalyst. Theoretical simulations first evidence that Co metal as the electron donator can form a built‐in electric field with CoS 2 and downshift the d‐band center, leading to the well‐optimized adsorption strength for lithium polysulfides on CoS 2 , thus contributing a favorable way for expediting the redox reaction kinetics of LiPSs. As verification of prediction, a Co/CoS 2 heterostructure implanted in porous hollow N, S co‐doped carbon nanocage (Co/CoS 2 @NSC) is designed to realize the electronic configuration regulation and promote the electrochemical performance. Consequently, the batteries assembled with Co/CoS 2 @NSC cathode display an outstanding specific capacity and an admirable cycling property as well as a salient property of 8.25 mAh cm −2 under 8.18 mg cm −2 . The DFT calculation also reveals the synergistic effect of N, S co‐doping for enhancing polysulfide adsorption as well as the detriment of excessive sulfur doping.