▎ 摘　　要

NOVELTY - Preparation of nickel(II) oxide (NiO)/reduced graphene oxide (rGO) composite thin film involves preparing NiO nanocrystalline powder, and dissolving powder in n-hexane; oxidizing graphite using Hummers' method, calcining in muffle furnace at 1100 degrees C, mixing with ethanol, ultrasonicating mixture for 2 hours, adding ethylene glycol, and reacting in hydrothermal reactor at 200 degrees C for 24 hours to obtain reduced graphene; and mixing NiO solution and reduced graphene at volume ratio of 3:1, stirring mixture for 2 hours, coating mixture on conductive substrate, and annealing. USE - Method for preparing NiO/rGO composite thin film (claimed). ADVANTAGE - The method has simple process, high repeatability, and low cost. The obtained film has good electrochromic performance and optical performance. DETAILED DESCRIPTION - Preparation of NiO/rGO composite thin film comprises dissolving nickel nitrate in methanol, adding oleic acid, adding obtained solution rapidly into oleylamine heated to 190 degrees C, heating further mixture to 260 degrees C for 30 minutes, cooling to room temperature, adding acetone and n-hexane to precipitate NiO nanocrystalline powder, and dissolving powder in n-hexane; oxidizing graphite using Hummers' method, calcining in muffle furnace at 1100 degrees C, mixing with ethanol, ultrasonicating mixture for 2 hours, adding ethylene glycol, and reacting in hydrothermal reactor at 200 degrees C for 24 hours to obtain reduced graphene; and mixing NiO solution and reduced graphene at volume ratio of 3:1, stirring mixture for 2 hours, coating mixture on conductive substrate, and annealing.