Assembling phytic acid into Ti₃C₂T_x MXene for enhanced lithium storage kinetics

MXenes with unique two-dimensional (2D) open structure, high metallic conductivity, and tunable interlayer spacing are attractive for lithium-ion batteries (LIBs). However, the nanosheets restacking of MXenes hinders ion accessibility, resulting in the limited capacity, poor rate performance and sluggish ion-transport kinetics. Herein, phytic acid (PA), containing a myoinositol ring coupled with six phosphate groups, was first assembled into Ti₃C₂T_x MXene (M-PA) to achieve a supramolecular self-assembly via hydrogen bonds. The as-prepared 3D porous architecture of M-PA with larger interlayer spacing is favorable for the ion transfer, thus facilitating the improvement of lithium storage performance. As a result, the M-PA electrode exhibits a specific capacity of 391.7 mA h g^-1 at 0.1 A g^-1 (vs. 165.6 mA h g^-1 for the Ti₃C₂T_x counterpart) and outstanding ion-transport kinetics. This work highlights the delicate construction of high-performance MXene-based electrodes with 2D materials as the building blocks.