Effect of Cation Vacancy on the Lithium Storage Behavior of Titanium Dioxide

Abstract

Titanium dioxide (TiO2) has been studied as an anode material of lithium ion battery for a long time. It has the advantages of low volume change and chemical stability, but it has serious problems such as a low capaciy and poor conductivity. We synthesized anatase TiO2 with different vacancies, which was able to affect the battery performance of TiO2. In general, TiO2 has oxygen vacancy, but anatase TiO2 with titanium vacancy can be synthesized by hydrothermal reaction and calcination. Physical and electrochemical properties of TiO2 with titanium vacancy were compared to TiO2 with oxygen vacancy. To exclude other factors that affect the battery performance, the grain size and surfae area were matched as closely as possible. The presence of titanium vacancy was confirmed through lattice variation and Raman analysis. Titanium vacancy and oxygen vacancy had a similar effect on the capacity, but long-term cycling test revealed that retention of p-TiO2 was higher than that of n-TiO2; because of structual instablity of n-TiO2 that is confirmed by XRD analysis.