Solvothermal synthesis of nano-LiMnPO4 from Li3PO4 rod-like precursor: reaction mechanism and electrochemical properties

Abstract

A simple one-pot solvothermal approach is employed to synthesize LiMnPO₄ (LMP) nanomaterials by using Li₃PO₄ nanorods and MnSO₄·H₂O as the precursors. Various experimental parameters, such as volume ratio of polyethylene glycol 600 (PEG600) to water, reactant feeding order, reaction time and pH value, are discussed. The phase and morphology changes of the product were characterized by XRD and TEM. A reaction mechanism is proposed based on the characteristic results. The charge–discharge properties show that the LMP nanomaterials synthesized at 180 °C for 4 h at a pH value of 6.46 followed by sintering with glucose at 600 °C for 3 h under argon atmosphere present the highest discharge capacity of 147 mA h g⁻¹ at 0.05 C rate (i.e. 8.55 mA g⁻¹ of current rate) under a galvanostatic charging–discharging mode, and it can retain 93% of the initial capacity of 46.6 mA h g⁻¹ after cycling 200 times at 1 C rate. Cyclic voltammetry (CV) was also used to investigate the carbon coated LMP electrode.