Hybrid Ascharite/Reduced Graphene Oxide with Polysulfide Adsorption Host for Advanced Lithium–Sulfur Batteries

• Published in: Inorganic chemistry 2024-02, Vol.63 (6), p.3107-3117
• Main Authors: Zhao, Xiaojun, Dang, Yubo, Ma, Hongzhou, Bai, Panqing, Li, Wangzi, Liu, Zhi-Hong
• Format: Article
• Language: English
• ISSN: 0020-1669; 1520-510X
• DOI: 10.1021/acs.inorgchem.3c04081

Balancing the adsorption of lithium-polysulfide intermediates on polar host material surfaces and the effect of their electronic conductivity in the subsequent oxidation and reduction kinetics of electrochemical reactions is necessary and remains a challenge. Herein, we have evaluated the role of polarity and conductivity in preparing a series of ascharite/reduced graphene oxide (RGO) aerogels by dispersing strong polar ascharite nanowires of varying mass into the conductive RGO matrix. When severed as Li–S battery cathodes, the optimized S@ascharite/RGO cathode with a sulfur content of 73.8 wt % demonstrates excellent rate performance and cycle stability accompanied by a high-capacity retention for 500 cycles at 1.0 C. Interesting advantages including the enhanced adsorption ability by the formation of the Mg–S and Li bonds, the continuous and quick electron/ion transportations assembled conductive RGO framework, and the effective deposition of Li2S are combined in the ascharite/RGO aerogel hosts. The electrochemical results further demonstrate that the polarity of ascharite components for the S cathode plays a dominant role in the improvement of electrochemical performance, but the absence of a conductive substrate leads to serious capacity attenuation, especially the rate performance. The balanced design protocol provides a universal method for the synthesis of multiple S hosts for high-performance LSBs.