▎ 摘　　要

NOVELTY - Preparing graphene/silicon dioxide composite particle comprises (i) (a) preparing graphene oxide solution and (b) preparing graphene oxide/silicon dioxide solution and dispersed graphene oxide/silicon dioxide solution; and (ii) (a) reducing agent and graphene oxide into graphene oxide/silicon dioxide, then heating mixture and reacting to obtain graphene/silicon dioxide gel, (b) washing graphene/silicon dioxide liquid gel with ethanol, and then dissolving graphene oxide with same solvent to replace gel liquid, and (iii) drying graphene/silicon dioxide liquid gel or freezing and drying. USE - The method is useful for preparing graphene/silicon dioxide composite particle (claimed). ADVANTAGE - The composite particle: has excellent physical properties, low density, high porosity, high surface area, low thermal conductivity and stability of chemical properties. DETAILED DESCRIPTION - Preparing graphene/silicon dioxide composite particle comprises (i) (a) mixing graphene oxide with solvent, then placing on the ultrasound system for further ultrasonic dispersion to obtain graphene oxide solution having a concentration of 0.1-50 mg/ml, where the frequency of ultrasound is 100-5000 HZ, the temperature is 0-100 degrees C, the ultrasonic time is 0.1-4 hours and (b) adding silicon dioxide and graphene oxide in a mass ratio of 1-50:1, then adding silicon dioxide into graphene oxide solution and performing ultrasonic dispersion to obtain graphene oxide/silicon dioxide solution, where the frequency of ultrasonic wave is 100-5000 W, the time is 0.1-4 hours and controlling the temperature to less than 50 degrees C; adding dispersing agent and silicon dioxide in mass ratio of 1-20:1, then adding dispersing agent into graphene oxide/silicon dioxide solution, mixing solution for 1-150 minutes at room temperature to completely dissolving dispersing agent to obtain dispersed graphene oxide/silicon dioxide solution; and (ii) (a) reducing agent and graphene oxide into graphene oxide/silicon dioxide solution in mass ratio of 0.1-30:1 for 1-180 minutes, then heating mixture at a constant temperature of 10-80 degrees C and reacting for 0.5-36 hours to obtain graphene/silicon dioxide gel, (b) washing graphene/silicon dioxide liquid gel with ethanol, and then dissolving graphene oxide with same solvent to replace gel liquid, replacement for 1-3 days, and (iii) drying graphene/silicon dioxide liquid gel or freezing and drying in a drying to obtain final product.