▎ 摘　　要

NOVELTY - Graphene-silicon dioxide composite material wall phase change nanocapsule, is claimed. The graphene-silicon dioxide composite material wall phase change nanocapsule has core-shell structure; the core is core material which is phase change material, and shell is wall material which is graphene-silica composite material; the mass percentage of graphene in the wall material is 0.17-6.67 wt.%, and the particle diameter of the phase change nanocapsule is 100-500 nm. USE - Used as graphene-silicon dioxide composite material wall phase change nanocapsule. ADVANTAGE - The phase change nanocapsule: has good thermal conductivity and thermal stability. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for preparing the graphene-silicon dioxide composite material wall phase change nanocapsule comprising (1) mixing phase change material with alkoxysilane compound in reaction vessel to form oil phase; (2) adding cationic surfactant to the oil phase obtained in the step (1), adding deionized water/ethanol mixed solvent as aqueous phase, emulsifying under stirring or shearing force, ultrasonic refining, forming fine emulsion in which the oil phase is dispersed in aqueous phase to form nano-sized droplets; (3) dispersing graphene in deionized water with the auxiliary anionic surfactant, and ultrasonically dispersing to obtain a stable graphene dispersion; (4) adding the graphene dispersion obtained in the step (3) to the fine emulsion obtained in the step (2), sequentially adding ethanol and alkaline catalyst, obtaining mixture of the phase change nanocapsule and aqueous phase after reaction; and (5) filtering mixture obtained in the step (4) to obtain phase-change nanocapsule, washing with deionized water, drying to obtain graphene-silica composite wall phase change nanocapsule in the form of black powder.