Ball-milled few-layer Ti3C2Tx MXene as a multifunctional additive for constructing robust conductive networks in Li1.2Mn0.4Ti0.4O2 rock-salt cathodes

Cation-disordered rocksalt (DRX) cathodes have emerged as promising candidates for next-generation energy storage due to their high theoretical capacity and reliance on earth-abundant elements. However, their practical implementation is severely limited by inherently sluggish electrical conductivity and restricted Li + diffusion. In this study, we propose a facile structural engineering strategy by incorporating few-layer Ti 3 C 2 T x MXene, prepared via ball-milling, as a multifunctional conductive additive for Li 1.2 Mn 0.4 Ti 0.4 O 2 DRX cathodes. By synergistically coupling 2D MXene nanosheets with conventional 0D carbon black, a robust hierarchical “point-to-surface” conductive network is successfully constructed. Systematic electrochemical characterizations reveal that optimal MXene integration not only serves as a physical protective barrier but also provides accessible sites for transient lithium-ion storage, thereby collectively accelerating Li + /electron transport and mitigating interfacial polarization. Consequently, the optimized composite electrode with 20% MXene additive delivers a remarkably high initial discharge capacity of 203.7 mAh g − 1 at 0.1 C, substantially outperforming the pristine electrode (165.2 mAh g − 1 ), alongside markedly superior rate capability and structural reversibility. This work provides critical mechanistic insights into MXene-mediated modifications and offers a sustainable pathway for the design of high-performance Mn-based DRX cathodes.