H2O2 assisted hydrothermal oxidation of partially etched vanadium carbides (MXene) and their electrochemical properties as anode for Li-ion batteries

The novel V2CTx MXenes have gained increasing attention as anode materials in lithium-ion batteries, but to boost their practical to the theoretical values is still challenging. Herein, the partially etched V2CTx was oxidized in the presence of H2O2 through a hydrothermal reaction and the electrochemical properties of as-obtained oxidized V2CTx were assessed. It is illustrated that the oxidized V2CTx possesses a large surface interlayer spacing, and enriched with VO2 (A) and O-terminate groups. Once used as anode materials for Li-ion batteries, the oxidized V2CTx shows enhanced specific lithium ion storage capacities of 318 mAh·g−1 at 100 mA·g−1 after 100 cycles, and 125 mAh·g−1 at 1000 mA·g−1 after 1000 cycles, and better cycling stability and excellent rate performance over the V2CTx.