▎ 摘　　要

NOVELTY - Preparing sodium-iron-based mixed-phosphate (Na4Fe3(PO4)2(P2O7) by using homogeneous method, comprises (i) taking sodium source, iron source, phosphorus source and carbon source according to the stoichiometric ratio, adding organic solvent, and dispersing, (ii) placing the dispersion in a sand mill, adding sanding media, and wet-sanding for 2-10 hours, with the particle size controlled between 1 and 0.1 mu m, (iii) transferring the sand-milled reaction liquid to a spray dryer, and spraying and granulating, and (iv) placing the sprayed powder in an inert atmosphere, sintering at 400-650 degrees C for 4-15 hours to obtain Na4Fe3(PO4)2(P2O7 powder. USE - The mixed-phosphate is useful as sodium ion battery cathode material in sodium ion battery (claimed). ADVANTAGE - The mixed-phosphate: is economical, and environmentally friendly; has excellent cycle stability; and can provide an ideal anode for commercial sodium ion batteries.