Guangxi Key Laboratory of Electromagnetic Chemical Functional Substances, School of Chemical and Biological Engineering, Guilin University of Technology, Guilin 541004, China
This paper summarizes the applications of TiO2 with oxygen vacancies composites in sodium-ion battery anode materials at home and abroad in recent years. The paper firstly introduces the methods of TiO2 with oxygen vacancies generation, such as chemical reduction, anoxic conditions, metallic or non-metallic doping, etc., and some common methods of oxygen vacancy characterization, such as EPR, XPS, STEM and other techniques. The role of oxygen vacancies in TiO2 is highlighted, which can significantly affect the physical and chemical properties of TiO2, including energy band structure, crystal structure and adsorption properties. It is shown that oxygen deficient TiO2 can significantly improve the sodium storage properties. Also, the electron/ion transfer impedance is reduced by modulating the ratio of TiO2(001) crystallographic activity through the crystallographic surface control agent NaBF4. Finally, several methods for the preparation of oxygen vacancyrich TiO2 composites and their practical applications in the anode materials of sodium-ion batteries are exemplified, confirming that the introduction of oxygen vacancies can improve the electrical conductivity of TiO2 and facilitate the acceleration of sodium ion adsorption and diffusion kinetics, resulting in excellent electrochemical performance. This paper summarizes the research on TiO2 with oxygen vacancies composites, hoping to provide the basis and support for creating higher performance TiO2 with oxygen vacancies composites in the future.