Multidimensional VO2 nanotubes/Ti3C2 MXene composite for efficient electrochemical lithium/sodium-ion storage

The nature of vanadium oxides with multiple valence states and a rich species of oxides facilitates the construction of high performance batteries. Among these, vanadium dioxide (VO2), despite offering several advantages, is seldom reported in anode materials due to its inferior cycling stability and rate performance caused by large volume changes. Herein, we employed a rational structural strategy to assemble VO2-NTs/Ti3C2 anode with a multidimensional cross-linked structure using VO2 nanotubes (VO2-NTs) and Ti(3)C(2)Tx MXene. Specifically, the abundant multidimensional channels of VO2-NTs/Ti3C2 reduce the diffusion impedance of the ions, and the enhanced intrinsic conductivity and highly robust structure solve the problems originally present in VO2, which are verified in characterization and density functional theory calculations. Consequently, the composite electrode shows ultra-high reversible capacity (1425 mAh g(-1) at 1 A g(-1)), excellent cycling performance (516 mAh g(-1) at 5 A g(-1) after 2000 cycles) and superior rate performance (703 mAh g(-1) at 10 A g(-1)), and also exhibits decent sodium storage performance, representing the best comprehensive battery performance of VO2-based anodes to date.

Automated summary

This study utilized a rational structural strategy to assemble a multidimensional cross-linked VO2-NTs/Ti3C2 anode using VO2 nanotubes and Ti(3)C(2)Tx MXene. The composite electrode exhibited ultra-high reversible capacity, excellent cycling performance, superior rate performance, and decent sodium storage performance.