Controlling microstructure and electrochemical performance of TiO2 film by defect engineering

Abstract

TiO2 film structure has a significant impact on its electrochemical performance. Improving the film structure has become an important means to promote the electrochemical performance of TiO2. Growth of high quality TiO2 film is extremely important for corrosion resistance or optoelectronics applications; however, it is considerable challenging using conventional methods. Herein, we report on a novel control method based on the defect engineering. The results show that the defect concentration is controlled by adjusting the mechanical activation time with tunable film thickness from 155 nm to 998 nm. Moreover, the pure titanium with high activity anodized display the best high crystallinity and corrosion resistance probably due to the Gibbs free energy educed by mechanical activation, which increased the defect concentration and reaction rate constant, and promoted the transition of unstable Ti3+ and Ti2+ to stable Ti4+. Our findings provide an effective method for the fabrication of TiO2 films, which can pave the way to further provide theoretical support for surface interfacial reactions.