▎ 摘　　要

NOVELTY - A thin film capacitor preparing method involves coating oxidized graphene water solution on insulating thin film at 70-110 degrees C to obtain coating, and putting the thin film into a drying oven at 30-120 degrees C to be dried and solidified. The thin film is reacted with hydroiodic acid solution. The thin film is dried in the drying oven at 30-120 degrees C, and the graphene/insulating thin film composite thin film is obtained. A screen zone is reserved for the graphene/insulating thin film composite thin film, and a thin film capacitor is formed finally after cutting and winding are conducted. USE - Method for preparing thin film capacitor. ADVANTAGE - The method enables preparing thin film capacitor with high energy density and high power density, reduced size and improved electric capacity in cost-effective manner. DETAILED DESCRIPTION - A thin film capacitor preparing method involves coating oxidized graphene water solution with the concentration of 0.1-100 mg/l on insulating thin film at 70-110 degrees C to obtain coating with the thickness of greater than or equal to 100 Angstrom and speed of 3-30 m/s, and putting the thin film into drying oven at 30-120 degrees C to be dried and solidified. The thin film is reacted with hydroiodic acid solution with 1-50 mass% under the unfolding state for 5-90 minutes. The thin film is dried in the drying oven at 30-120 degrees C, and the graphene/insulating thin film composite thin film is obtained. A screen zone is reserved for the graphene/insulating thin film composite thin film, and a thin film capacitor is formed finally after cutting and winding are conducted.