▎ 摘　　要

NOVELTY - The electrochemical polishing method involves taking a substrate-to-be-polished as an anode and insoluble metal as cathode, and electrolyzing, where the electrolyte for electrolysis comprises mixed liquid of phosphoric acid, sulfuric acid, deionized water and polyethylene glycol. USE - Electrochemical polishing method of graphene film (claimed). ADVANTAGE - The method enables electrochemical polishing with high repeatability and effectively improved substrate surface topography, removes small scratches, and eliminates the substrate surface defects. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: (1) electrochemical polishing platform; and (2) preparation method of graphene film.