▎ 摘　　要

NOVELTY - Preparing graphene film with good flexibility comprises (i) ultrasonically treating graphene oxide dispersion in deionized water to obtain 0.5-4 mg/ml uniform graphene oxide suspension; (ii) pouring graphene oxide suspension into a polytetrafluoroethylene petri dish, and introducing in oven and drying at 20-45 degrees C to obtain graphene oxide film; (iii) taking 80% hydrazine hydrate solution, coating one side of ceramic block with brush pen, placing graphene oxide film, coating the other surface of the graphene oxide film with hydrazine hydrate by brush pen, pressing other ceramic block to upper surface forming sandwich structure, and fixing with clip, where the amount the hydrazine hydrate is 50 ml/cm2; (iv) introducing sandwich structure into reaction kettle, placing reaction kettle in oven, and heating at 80-110 degrees C for 180-540 minutes to obtain reduced graphene oxide film; (v) annealing reduced graphene oxide film at 600-1300 degrees C for 30-120 minutes under nitrogen atmosphere. USE - The film is useful as an electrode material of low-temperature supercapacitor. ADVANTAGE - The film solves the power supply problem of low-temperature flexible equipment.