▎ 摘　　要

NOVELTY - Preparing nitrogen-doped porous reduced graphene oxide by recycling waste lithium ion battery anode graphite material comprises preparing graphene oxide by using graphite material from negative electrode of a waste lithium ion battery, using graphene oxide, nitrogen source, activator and water as raw materials, making macroscopic graphene body through constant temperature reaction, hydrothermal reaction, and freeze-drying, calcining, pickling, washing with water, and drying macroscopic graphene body to obtain nitrogen-doped porous reduced graphene oxide. The nitrogen source includes melamine, thiourea, polyaniline, ammonium chloride, urea, phenanthroline, biuret, ammonium nitrate and/or dicyandiamide, the activator includes potassium hydroxide, sodium hydroxide, potassium bicarbonate, phosphoric acid, zinc chloride, potassium acetate and/or potassium oxalate. The acid used in pickling includes acetic acid, nitric acid, carbonic acid and/or phosphoric acid. USE - The method is useful for preparing nitrogen-doped porous reduced graphene oxide in potassium ion battery (claimed). ADVANTAGE - The method: fully utilizes expanded layer spacing of graphite material for negative electrode of waste lithium ion battery; provides loose, porous, and large interlayer spacing nitrogen-doped reduced graphene oxide. The oxide has long-range ordered structure, which is conducive to maintaining a stable structure during ion intercalation process and improving electrochemical performance of material prepared from recycled graphite. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for: nitrogen-doped porous reduced graphene oxide, prepared by above method. use of nitrogen-doped porous reduced graphene oxide in potassium ion battery. cathode, comprising nitrogen-doped porous reduced graphene oxide.