Structure and Magnetic Properties of AO and LiFePO(4)/C Composites by Sol-Gel Combustion Method

LiFePO(4) takes advantage of structure stability, safety and environmental friendliness, and has been favored by the majority of scientific researchers. In order to further improve the properties of LiFePO(4), AO-type metal oxides (MgO and ZnO) and LiFePO(4)/C composites were successfully prepared by a two-step sol-gel method. The effects of AO-type metal oxides (MgO and ZnO) on LiFePO(4)/C composites were studied. TG, XRD, FTIR, SEM and VSM analysis showed that the final product of the MgO and LiFePO(4)/C composite was about 70.5% of the total mass of the precursor; the complete main diffraction peak of LiFePO(4) and MgO can be found without obvious impurity at the diffraction peak; there is good micro granularity and dispersion; the particle size is mainly 300 nm; the saturation magnetization (Ms), the residual magnetization (Mr) and the area of hysteresis loop are increased with the increase in MgO content; and the maximum Ms is 11.11 emu/g. The final product of ZnO and LiFePO(4)/C composites is about 69% of the total mass of precursors; the complete main diffraction peak of LiFePO(4) and ZnO can be found without obvious impurity at the diffraction peak; there is good micro granularity and dispersion; the particle size is mainly 400 nm; and the coercivity (Hc) first slightly increases and then gradually decreases with the increase of zinc oxide.