Optimizing reduced graphene oxide/MXene composites as sulfur hosts for lithium-sulfur batteries: A systematic investigation

Abstract

Large volume changes, the insulating nature of sulfur, and the lithium polysulfides (LiPSs) shuttle effect significantly hinder the practical application of lithium-sulfur (Li-S) batteries. In this study, reduced graphene oxide/MXene (rGO/MXene) composites were investigated as potential sulfur host materials. Since the rGO-to-MXene ratio influences electrical conductivity, LiPSs confinement, and structural stability, MXene contents of 10 wt%, 20 wt%, and 30 wt% were systematically evaluated. The (rGO/MXene10)_S60 electrode exhibited the most promising performance, delivering an initial discharge capacity of 981 mAh/g and retaining 606 mAh/g after 100 cycles with Coulombic efficiency (CE) above 97 %. These results demonstrate that a 9:1 rGO-to-MXene ratio optimally enhances conductivity, structural stability, and LiPSs anchoring, making it a promising sulfur host for Li-S batteries.