Integrating Conductivity, Immobility, and Catalytic Ability into High‐N Carbon/Graphene Sheets as an Effective Sulfur Host

作者：Huifang Xu, Qingbin Jiang, Bingkai Zhang, Chao Chen, Zhan Lin · 发表于：Advanced Materials · 年份：2019 · DOI：10.1002/adma.201906357 · 被引用次数：161 · 研究领域：Advanced Battery Materials and Technologies、Advancements in Battery Materials、Advanced battery technologies research

Abstract Lithium–sulfur (Li–S) batteries are considered to be one of the most promising candidate systems for next‐generation electrochemical energy storage. The major challenge of this system is the polysulfide shuttle, which results in poor cycling efficiency. In this work, a highly N‐doped carbon/graphene (NC/G) sheet is designed as a sulfur host, which combines the merits of abundant N active sites and high electrical conductivity to achieve in situ anchoring–conversion of lithium polysulfides (LiPSs). Such a host not only has strong binding with LiPSs but also promotes redox kinetics, which are revealed by both experimental investigations and theoretical studies. The sulfur cathode based on the NC/G host exhibits a high initial capacity of 1380 mA h g−1 and a superior cycle stability with a low capacity decay of 0.037% per cycle within 500 cycles at 2 C. Steady areal capacity with a high sulfur loading (5.6 mg cm−2) is also attained even without the addition of LiNO3 in the electrolyte. This work proposes and illustrates the importance of in situ anchoring–conversion of LiPSs, offering a new strategy to design multifunctional sulfur hosts for high‐performance Li–S batteries.