The phase structure of Fe doped LiFe_xMn_(2-x)O_4 prepared by a molten-salt combustion synthesis

摘要

Fe doped LiFe_xMn_(2-x)O_4 materials were prepared by a low-temperature molten-salt combustion synthesis method. The phase structure and compositions of the products were determined by X-ray diffraction (XRD). The investigation on Fe doping content indicated that the main phase of the as-prepared products was LiFe_xMn_(2-x)O_4, and the impurity was Mn_2O_3. With increasing Fe doping content, the relative content of Mn_2O_3 and the lattice parameter of the products were decreased, and the crystallinity was increased. The study of the calcination temperature on LiFe_(0.1)Mn_(1.9)O_4 suggested that the main phase of the LiFe_(0.1)Mn_(1.9)O_4 materials prepared at 300-600°C was LiFe_(0.1)Mn_(1.9)O_4. Mn_3O_4 and MnO impurities could be investigated in the product prepared at 300°C, and single impurity Mn_2O_3 could be observed in the products prepared at 400-600°C. The relative content of Mn_2O_3 decreased, and the lattice parameters and grain size of the products were increased with increasing calcination temperatures.