Unlocking Rapid and Durable Sodium‐Ion Storage in MXene via Organic Molecular Welding

ABSTRACT Achieving fast and reversible sodiation/desodiation in MXene materials remains an eye‐catching yet unresolved challenge. This work introduces a benzaldehyde‐welded Ti 3 C 2 MXene (Ti 3 C 2 –BD) as a high‐performance anode material for sodium‐ion batteries (SIBs). This functionalization boosts electrochemical activity and structural stability while directly addressing key limitations like interlayer stacking and rapid performance degradation. With these advantages, the Ti 3 C 2 –BD anode delivers a specific capacity of 54.5 mAh g −1 at 10 A g −1 and retains 51.1 mAh g −1 after 2500 cycles at 5 A g −1 , demonstrating exceptional rate capability and cycling stability. In full‐cell systems, Ti 3 C 2 –BD achieves an energy density of 205.3 Wh kg −1 . Structural and kinetic analyses reveal its stable architecture, superior Na + ion adsorption, and favorable diffusion kinetics. This study offers a strategic approach for designing MXene‐based anodes with high capacity, rate capability, and long‐term stability, providing both theoretical and practical advancements in SIBs technology.