Enhancing Bidirectional Lithium–Sulfur Battery Performance Through Synergistic‐Induced 3D Li 2 S Deposition

Abstract Lithium–sulfur (Li–S) batteries rely on the reversible conversion between sulfur and Li 2 S, where enhancing the kinetics of sulfur redox reactions is critical for practical applications. In this work, a hierarchical MXene@MoSe 2 porous carbon nanofibers (PCNFs) architecture is designed to promote 3D Li 2 S deposition. Notably, the PCNFs scaffold offers a porous conductive framework in which the MXene component effectively suppresses polysulfides diffusion, and surface‐anchored MoSe 2 nanosheets strategically expose catalytically active sites while preventing insulation caused by Li 2 S accumulation. The investigation reveals distinct catalytic behaviors of MXene@MoSe 2 toward Li 2 S deposition, with their heterojunction interface synergistically facilitating 3D nucleation and mitigating surface passivation. Additionally, the spontaneous formation of a built‐in electric field at heterostructure accelerates lithium ion diffusion, thereby enhancing the bidirectional conversion kinetics of Li 2 S. Comprehensive theoretical calculations and experimental characterizations collectively demonstrate the superior bifunctional catalytic activity of MXene@MoSe 2 PCNFs. As a result, Li–S batteries incorporating this catalyst exhibit exceptional performance metrics, including an capacity decay rate of merely 0.023% per cycle over 2000 cycles. This work presents a promising paradigm for designing advanced electrocatalysts to optimize Li 2 S redox chemistry in Li–S batteries.