▎ 摘 要
Anatase TiO2 shows excellent long-term cycling stability as an anode for sodium-ion batteries. However, the low specific capacity and poor rate capability resulting from its intrinsic low electrical conductivity limit its applications. In this work, TiO2 nanoparticles were coated with reduced graphene oxide (RGO) using a combination of spray-drying and heat treatment. Electrochemical tests showed that the obtained RGO/TiO2 composites had improved electrochemical performances. The reversible capacities of the RGO/TiO2 [4.0% (w)] composites were 183.7 mAh.g(-1) (20 mA.g(-1)), 153.7 mAh.g(-1) (100 mA.g(-1)), and 114.4 mAh.g(-1) (600 mA.g-1). Bare TiO2 showed low capacities of 93.6 mAh.g(-1) (20 mA.g(-1)), 69.6 mAh.g(-1) (100 mA.g(-1)), and 26.5 mAh.g(-1) (600 mA.g(-1)). The 4.0%(w) TiO2/RGO composites exhibited good cycling stability with a charge capacity of 146.7 mAh.g(-1) at a current density of 100 mA.g(-1) after 350 cycles, compared with 68.8 mAh.g(-1) for bare TiO2. RGO modification is a promising method for improving the electrochemical performances of the sodium energystorage materials.