关键词: 二氧化钛, 钠离子电池, 纳米复合材料, 掺杂, 氧缺陷

Abstract: Titanium dioxide (TiO₂) represents a stable, low-cost, and nontoxic anode material for sodium-ion batteries (SIBs). However, the low electrical conductivity limits its electrochemical activity (specific capacity) and rate capability, hindering its widespread applications. In this article, we show that different crystal forms of TiO₂ have different pore structures, resulting in the distinct sodium storage capacities. Accordingly, the article introduces how TiO₂ microstructures influence sodium storage. The nanoparticle structure can improve the rate performance of the material due to its short ion diffusion distance, and the internal cavity of the hollow structure is beneficial to cycle stability. In addition, we conclude that the conductivity of the material can be enhanced by oxygen defects or doping metals/non-metals. Lots of experimental results show that TiO₂ with carbon or metal composite structures has excellent electrochemical performance. In brief, this article comprehensively summarizes the effects of microstructure, oxygen vacancy, doping, and compositing on the conductivity and electrochemical performances of TiO₂-based anode materials. Beyond that, future research directions for TiO₂-based anode materials are also predicted at the end of this review.

Key words: TiO₂, sodium-ion battery, nanocomposites, doping, oxygen vacancy