▎ 摘　　要

NOVELTY - Preparing zinc oxide-reduced graphene oxide composite photocatalyst involves adding 1.0-2.5 g sodium nitrate and 50-120 mL 98% concentrated sulfuric acid into 250 mL four-mouth flask, cooling in an ice bath, adding with 2-5 g graphite with stirring when the temperature of the reaction system is lower than 5 degrees C, mixing evenly, stirring vigorously, slowly adding with 0.5-10 g potassium permanganate, while maintaining the temperature at 20 degrees C. The temperature of the reaction solution is raised to 35 plus minus 3 degrees C and the reaction is carried out for 120-180 min. USE - Method for preparing zinc oxide-reduced graphene oxide composite photocatalyst (claimed). ADVANTAGE - The method enables to prepare zinc oxide-reduced graphene oxide composite photocatalyst in simple manner, while avoiding the use of poisonous and harmful reducing agent. DETAILED DESCRIPTION - Preparing zinc oxide-reduced graphene oxide composite photocatalyst involves adding 1.0-2.5 g sodium nitrate and 50-120 mL 98% concentrated sulfuric acid into 250 mL four-mouth flask, cooling in an ice bath, adding with 2-5 g graphite with stirring when the temperature of the reaction system is lower than 5 degrees C, mixing evenly, stirring vigorously, slowly adding with 0.5-10 g potassium permanganate, while maintaining the temperature at 20 degrees C. The temperature of the reaction solution is raised to 35 plus minus 3 degrees C and the reaction is carried out for 120-180 min. The reaction mixture, after the completion of the reaction is drop-wise added with 90-230 mL distilled water, where the temperature of the system is suddenly raised to 90-98 degrees C, kept constant, added with distilled water, stirred for 15 mins and finally added with 55-150 mL deionized water to stop the reaction. The obtained reaction mixture is added with 7-18 mL 30% hydrogen peroxide solution to remove the un-reacted potassium permanganate, where the solution color changes from black brown to bright yellow, filtered when it is hot, washed with 3-5 wt.% hydrochloric acid solution to remove the metal ion, then finally washed with de-ionized water until the filtrate has no sulfate ion, which is detected by barium chloride solution and dried at 50-65 degrees C to obtain the graphite oxide. The graphite oxide is added with 0.06-0.1 mol sodium hydroxide and 60-100 mL polyol, ultrasonically dispersed for 20-40 min and added with 0.01-0.05 mol zinc powder to obtain the mixed solution, which is transferred into a ultrasonic reactor. The titanium alloy ultrasonic probe with a tip diameter of 15 mm is immersed in the reaction liquid, subjected to ultrasonic treatment reaction for 2 min, cooled to room temperature and collected the precipitate, which is washed with 3-5 wt.% hydrochloric acid solution to remove the zinc powder and salts thereof. The obtained product is 3-5 times washed with absolute ethyl alcohol and distilled water respectively and vacuum dried at 60-80 degrees C to obtain the product.