Na3V2(PO4)3/C cathode material synthesized by normal temperature chemical reduction and sodiation method

Na3V2(PO4)3/C cathode material is synthesized through a novel normal temperature chemical reduction and sodiation method, by using oxalic acid as both a reducing agent and a carbon source. During the mechanical activation process, the color of raw materials changes from buff to green indicating that the pentavalent vanadium ion is reduced. The XRD results show that the amorphous precursor can be transformed into well-crystallized Na3V2(PO4)3 after thermal treatment at 650 °C. SEM and TEM results indicate that the Na3V2(PO4)3 particles are porous and uniformly coated with an amorphous carbon layer. The sample shows an initial specific discharge capacity of 114.9 mAh g−1 at 0.05C rate (2.5-4.2 V), and exhibits good rate capability and cycling performance.