Synthesis and characterization of Li2MnP2O7/C composite by a combination of spray pyrolsis and wet ball milling followed by annealing

A Li2MnP2O7/C composite was synthesized by a combination of spray pyrolysis and wet ball milling followed by annealing. The peaks of the Li2MnP2O7/C composite obtained by X-ray diffraction analysis were indexed to the monoclinic structure with the space group P21/c. Field-emission scanning electron microscopy and transmission electron microscopy together with energy-dispersive spectroscopy verified that the Li2MnP2O7/C composite consisted of agglomerates of Li2MnSiO4 primary particles, and that a thin carbon layer was partially formed on the surface of these agglomerates. The Li2MnP2O7/C composite cathode delivered a first discharge capacity of 72 mA h g−1 at 0.1 C and 60 °C, while the theoretical capacity is 110 mA h g−1 for the Mn3+/Mn2+ redox reaction. The cathode also showed good cycling performance over 15 cycles.