Investigation of Electronic Conductivity and Occupancy Sites of Mo Doped into LiFePO4 by ab Initio Calculation and X-ray Absorption Spectroscopy

Mo-doped LiFePO4 composite was synthesized by the solid state method, using (NH4)(6)MO7O24 center dot 4H(2)O as the starting doping material. The electrochemical properties of Mo-doped LiFePO4 were measured. The electronic structures of Mo-doped LiFePO4 were studied by ab initio calculations. With respect to the density of states (DOS) of the LiFePO4, in which no electronic states are at the Fermi level, the Mo doping is predicted largely impacting the conductivity. Experimental data of the electronic conductivity and of the electrochemical performance of Mo-doped LiFePO4 synthesized by a solid state reaction confirm the results of the calculations. To characterize the doped LiFePO4 structure and the type and the symmetry of the Mo sites, X-ray absorption spectroscopy (XAS) experiments were performed.