Strategies of tailoring 2D MXenes for enhancing Sulfur-Based battery performance

MXenes, a thriving class of two-dimensional (2D) transition metal carbides, nitrides, and carbonitrides, demonstrate considerable potential in diverse electrochemical energy storage applications. To leverage MXenes for high-performance sulfur-based batteries, researchers have employed various strategies to modify their properties, aiming to tackle challenges such as the notorious shuttle effect induced by soluble polysulfides, sluggish redox reaction kinetics, and substantial volume expansion during the lithiation process. This review article offers an overview of MXene modification strategies, emphasizing their significant potential in adjusting the composition, surface chemistry, and morphology to address one or more challenges specially in sulfur cathodes. We first discuss internal regulation methods of MXene, including surface group engineering, heteroatom doping, and high-entropy MXene synthesis, which have been demonstrated to enhance MXene-polysulfide interactions and facilitate polysulfide conversion. Subsequently, we provide a summary of the recent design methods and advancements made in MXene-derived and MXene-based composites, with a particular emphasis on electronic structure reconstruction at the heterointerface and their synergistic roles in Li-S batteries. Following this, we outline the utilization of MXenes to address the challenges encountered in metal-sulfur batteries beyond Li-S batteries. Concluding the review, we offer prospects for the future development of utilizing MXenes in practical sulfur-based batteries.