Enhanced Electrochemical Performance of Cu2+ doped TiO2 Nanoparticles for Lithium-ion Battery

Abstract

TiO2 nanoparticles doped with Cu2+ are synthesized via a facile one-step solvothermal method with a uniform distribution of 50-60nm. The X-ray photoelectron spectroscopy (XPS) results show that the Cu2+ are doped in the TiO2 crystal lattice uniformly. Due to the smooth replacement of the part of Ti4+ sites by Cu2+ in the samples, more Ti4+ vacancies are formed, which is a benefit to the Li+ diffusion and enhanced electrochemical properties. At the 5 C rate, the initial discharge capacity of TiO2 doped with 6 wt% Cu2+ reaches 83.4 mAhg-1. After 100 charge-discharge cycles, the discharge capacity is still 76.5 mAhg-1, showing a good cycling stability.