三价铁离子掺杂对钛酸锂结构和化学性能的影响

采用溶胶凝胶法制备Li4-x/3FexTi5-2x/3O12(x=0,0.03,0.06,0.09)粉体活性材料,并优化了最佳掺杂量为x=0.03。通过X射线衍射(XRD)、扫描电镜(SEM)、恒流充放电测试对材料进行结构、形貌及电化学性能表征。结果表明:掺杂适量的铁离子不会改变钛酸锂的尖晶石结构和形貌。1C时,Li3.99Fe0.03Ti4.98O12首次放电比容量为145.40 m A·h/g;纯相的首次放电比容量仅为116.95 m A·h/g。

Effect of Fe-doping on composition and electrochemical properties of lithium titanate

A series of Li_4-x/3Fe_xTi_5-2x/3O₁₂(x=0, 0.03, 0.06, 0.09)active materials were prepared by Sol-Gel method. The optimized iron doping amounts was x=0.03. Material structure, morphology and electrochemical performance were characterization by X-ray diffraction (XRD), Scanning electron microscope (SEM), Constant current charge-discharge test. The result showed that: After doping iron ions, the spinal structure and morphology did not changed after doping amount of iron ion. The discharge specific capacity of Li_3.99Fe_0.03Ti_4.98O₁₂ was increased at high current density, and the first discharge specific capacity was 145.40 mAh/g at 1C; however, the pure Li₄Ti₅O₁₂ was only 116.95 mAh/g.