Mechanochemical‐Assisted HF‐Free Etching of V 2 AlC for Tuning Interlayer Spacing and Electrochemical Behavior of V 2 CT x MXene Anodes

Two‐dimensional MXenes have emerged as promising anode materials for lithium‐ion batteries (LIBs), yet their synthesis commonly relies on hazardous hydrofluoric acid and often suffers from nanosheet restacking. Herein, we report a mechanochemical‐assisted HF‐free etching strategy for the synthesis of V 2 CT x MXene from V 2 AlC using a NaF/HCl system and systematically compare it with a conventional hydrothermal route. Ball‐milling etching significantly enhances Al extraction efficiency, reduces residual MAX content, and induces structural disorder, leading to expanded interlayer spacing and increased active surface sites. The optimized BM‐48 sample exhibits the lowest MAX/MXene intensity ratio (28.9%), enlarged c‐lattice parameter, and highly fragmented layered morphology. Electrochemically, BM‐48 delivers an initial charge capacity of 276 mAh g −1 and maintains 244 mAh g −1 after 30 cycles at 0.1 C, demonstrating superior rate capability with 100 mAh g −1 at 1 C, with lithium storage dominated by pseudocapacitive and surface‐controlled mechanisms. In contrast, hydrothermal samples show more ordered lamellar structures and improved structural activation during cycling, but lower initial capacities. The comparative analysis reveals that mechanochemical activation accelerates phase transformation and enhances Li + kinetics at the expense of increased defect‐induced side reactions. This work provides mechanistic insight into structure–property relationships in V 2 CT x MXene and demonstrates an alternative HF‐free synthesis route for high‐performance LIB anodes.