▎ 摘　　要

NOVELTY - Graphene synergistic thermal energy storage composite material, comprises azobenzene compound i.e. (E)-3-((4-amino-2,6-dimethoxyphenyl)diazenyl)-5-fluorobenzoic acid (I) and reduced graphene oxide, where (I) is grafted on surface of the sheet of reduced graphene oxide in covalent coupling manner. USE - The composite material is useful in solar energy storage device (claimed). ADVANTAGE - The composite material has low-temperature heat release performance and fast heat release rate, and excellent energy storage density. DETAILED DESCRIPTION - Graphene synergistic thermal energy storage composite material, comprises azobenzene compound i.e. (E)-3-((4-amino-2,6-dimethoxyphenyl)diazenyl)-5-fluorobenzoic acid of formula (I) and reduced graphene oxide, where (I) is grafted on surface of the sheet of reduced graphene oxide in covalent coupling manner. AN INDEPENDENT CLAIM is also included for preparing the graphene synergistic thermal energy storage composite material, comprises (i) mixing (I), sodium nitrite and dilute hydrochloric acid aqueous solution, and reacting to obtain azobenzene diazonium salt solution, and (ii) dispersing the product of step (i) in reduced graphene oxide, stirring and reacting to obtain final product.