▎ 摘　　要

NOVELTY - Zinc phosphide material comprises zinc phosphide. The zinc phosphide is doped with amorphous zinc phosphate. USE - The zinc phosphide material or zinc phosphide complex material is useful in preparing potassium ion battery cathode material (claimed). ADVANTAGE - The material: can buffer volume expansion of active zinc phosphide during charging and discharging by doping zinc phosphate in zinc phosphide; improves utilization rate of zinc phosphide material as potassium ion anode material; improves cycle stability of electrode material; enables one-step ball milling and redox reaction between raw material with simultaneously formation of zinc phosphide in situ; requires no other post-processing, which is conducive to large-scale production and use and compensates for decrease in electrical conductivity caused by presence of zinc phosphate by adding a carbon material. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for: preparing zinc phosphide material comprising ball milling the mixture of metal zinc, zinc oxide and phosphorus; a zinc phosphide complex material comprising carbon material and zinc phosphide material; preparing zinc phosphide complex material comprising ball milling the mixture of metal zinc, zinc oxide, phosphorus and carbon material, alternatively ball milling the mixture of zinc phosphide material and carbon material; and a potassium-ion battery comprising cathode, anode and an electrolyte. The active material of cathode is zinc phosphide material or zinc phosphide complex material. The electrolyte uses triethyl phosphate as solvent and potassium trifluoromethanesulfonimide as solute and the concentration is 1-5 mol/l. DESCRIPTION OF DRAWING(S) - The diagram shows a flow chart of a method for preparing zinc phosphide complex material (Drawing includes non-English language text).