High-Performance Lithium-Ion Storage of FeTiO₃ with Morphology Adjustment and Niobium Doping

Ferrous titanate (FeTiO₃) has a high theoretical capacity and physical and chemical properties stability, so it is a potential lithium anode material. In this study, FeTiO₃ nanopowder and nanosheets were prepared by the sol-gel method and the hydrothermal method. In addition, niobium-ion doping was carried out, the radius of Nb close to Ti so the Nb can easily enter into the FeTiO₃ lattice. Nb can provide more free electrons to improve the electrochemical performance. Then, the effects of the morphology and niobium doping on the microstructure and electrochemical properties of FeTiO₃ were systematically studied. The results show that FeTiO₃ nanosheets have a better lithium storage performance than nanopowders because of its high specific surface area. A certain amount of niobium doping can improve the electrochemical performance of FeTiO₃. Finally, a 1 mol% niobium-doping FeTiO₃ nanosheets (1Nb-FTO-S) electrode provided a higher specific capacity of 782.1 mAh g^-1 at 50 mA g^-1. After 200 cycles, the specific capacity of the 1Nb-FTO-S electrode remained at 509.6 mAh g^-1. It is revealed that an increased specific surface area and ion doping are effective means to change the performance of lithium, and the proposed method looks promising for the design of other inorganic oxide electrode materials.