Advances in MXene-based materials for high-sulfur-loading lithium–sulfur batteries

Lithium–sulfur (Li–S) batteries hold great promise for next-generation energy storage owing to their high theoretical energy density and the abundance of sulfur. Realizing their practical potential, however, requires electrodes with high sulfur loading, high areal capacity, and operation under lean electrolyte conditions—requirements that exacerbate intrinsic challenges such as polysulfide shuttling, sluggish redox kinetics, and poor electrode integrity. MXenes, a rapidly emerging family of two-dimensional transition metal carbides, nitrides, and carbonitrides, offer a unique combination of high electrical conductivity, abundant surface terminations, tunable chemistry, and structural robustness, making them particularly suited for high-loading Li–S systems. In this review, we summarize the key physicochemical properties of MXenes and elucidate their interaction mechanisms with sulfur/polysulfides, tracing recent advances in MXene-based materials for Li–S batteries across their applications on sulfur hosts, separator modification and lithium anode protection, with emphasis on their role in enabling high sulfur utilization and long-term cycling stability. The discussion highlights how MXenes and their heterostructures enhance polysulfide adsorption, catalyze redox conversion, and maintain electrode integrity, while also promoting uniform lithium deposition. Finally, we provide perspectives on the challenges and opportunities in tailoring MXene composition, surface chemistry, and structural design to accelerate the development of practical, high-energy-density Li–S batteries.