Preparation of High-Purity V₂C MXene and Electrochemical Properties as Li-Ion Batteries

A novel high-purity V2C MXene two-dimensional carbide, was successfully synthesized by etching V2AlC with sodium fluoride and hydrochloric acid at 90°C for 72 h. From the analysis of X-ray diffraction, energy dispersive spectra, and X-ray photoelectron spectroscopy, the purity of as-synthesized V2C MXene was >90 wt% with a few impurities of Na5Al3F14 and V2AlC. The V2C MXene made by this method was much purer than those made by HF etching at room temperature. The as-prepared V2C MXene showed excellent electrochemical properties as anode of lithium-ion batteries. The capacity can be 260 mAh g−1 if discharged under 370 mA g−1. The capacity was increased with charge cycles at high charge rate (500 mA g−1). It was suggested that V2C with high purity can be promising anode material with excellent performance.