One-step plasma electrolytic oxidation for TiO 2 /SnO 2 film as LIB anode

In this work, a SnO₂-doped TiO₂ film was rapidly prepared as lithium-ion battery anode by the one-step plasma electrolytic oxidation process on Ti foil. The whole process was carried out in an aqueous solution at room temperature and under atmospheric pressure without any heating or post-treatment. The prepared TiO₂/SnO₂ composite film exhibited a porous structure with large amounts of channels and cavities, which served as the Li ions diffusion paths and surface active sites for the interfacial electrochemical reactions. The film took full advantage of the high structural stability of TiO₂ and a high theoretical capacity of SnO₂, showing a high specific capacity (400 mAh g⁻¹ at 100 μA cm⁻²), an excellent cycling stability (200 cycles), and a good rate capability (capacity reversible after 1000 μA cm⁻²). This work provides a low-cost and high-efficiency approach for the preparation of binder-free oxide anodes for high-performance LIBs.