Preparation And Lithium Storage Properties Of TiO₂-based Composites

Among the new generation of secondary batteries,lithium ion batteries(LIBs)have the advantages of high energy,long cycle life,no pollution,environmental friendly,and portability,which is received much attention to be the electrochemical energy storage devices.When it comes to anode materials,titanium dioxide anode materials have unique advantages and have been widely studied by researchers in recent years.However,the conductivity of titanium dioxide itself is poor,and its low theoretical capacity is difficult to meet the needs of large-capacity energy storage batteries,which limits the development and application.Nanosized materials and preparation of composite materials can improve the defects of a single material,thereby improving the performance of the material.In this paper,titanium dioxide-based composite nanomaterials were prepared by dealloying method,the microstructure of the materials were characterized,and its electrochemical performance was systematically studied.Using rapid solidification technology to prepare AlTiSn and AlTiFe ternary alloy ribbons,followed by dealloying in alkaline solution to remove Al atoms and adjusting the process parameters to obtain nano-Sn particles doped amorphous TiO₂ Structure and flake-like nanoporous TiO₂/Fe₂O₃ composite materials.Because of the nano-scale three-dimensional porous structure,the TiO₂/Sn composite materials have a specific discharge capacity of 206 and 141 m A h g^-1 after 300 cycles at a current density of 300and 1000 m A g^-1,which doubles pure TiO₂ anode material.TiO₂/Sn composite materials have excellent rate performance and the addition of Sn greatly improves the electronic conductivity of the materials,which is benefit to the transmission of electrons during the charge and discharge process.The flake-like nanoporous TiO₂/Fe₂O₃ composite materials also have excellent rate performance and cycle performance under the current density of 300 and 1000 m A g^-1.The dealloying method is a promising preparation method.Its operation is simple,the alloy element ratio can be accurately controlled,the preparation process is free of the addition of toxic reagents,environmentally friendly and suitable for large-scale production.The prepared composite material has excellent lithium storage performance and has great potential in practical applications of lithium ion batteries.