▎ 摘　　要

NOVELTY - Linear double-branched azobenzene/graphene composite material is claimed. The linear double branch azobenzene grafted on the reduced graphene oxide layer in an array. USE - The material is useful as energy-storing material (claimed). ADVANTAGE - The material has excellent thermal stability, cycle performance, solar heat storage, prolongs half-life to 1000 hours, and stabilizes energy density at 158 Wh/Kg. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for preparing linear double-branched azobenzene/graphene composite material comprising (i) dissolving 4-aminobenzoic acid and sodium nitrite in deionized water, adding aqueous hydrochloric acid solution, placing in ice bath to obtain diazonium salt, then adding obtained diazonium salt solution into aniline hydrochloric acid aqueous solution under ice-cooling, adjusting pH value, stirring in ice bath under argon atmosphere for 5-7 hours, reacting overnight, washing resulting crude product with deionized water and anhydrous ethanol for many times, separating by chromatography using silica gel as stationary phase and ethyl acetate/n-hexane as eluent, distilling resulting fractions under reduced pressure, and drying under vacuum to obtain 4-((4-phenylaniline)dodecenylbenzoic acid, adding 4-((4-phenylaniline)dodecenylbenzoic acid and sodium hydroxide into dimethylformamide/water mixed solution, then adding di-tert-butyl dicarbonate under ice-cooling, reacting to room temperature for 28-32 hours, acidifying reaction product with hydrochloric acid, then adding deionized water, filtering precipitate, repeatedly washing with deionized water and brine to obtain solid, dissolving product in dichloromethane, adding oxalyl chloride, then adding dimethylformamide into mixture for 3-5 hours, distilling reaction solution under reduced pressure, and redissolving in dichloromethane, (ii) adding solution of p-aminoazobenzene-4-sulfonic acid and N,N-diisopropylethylamine into dichloromethane, then adding solution into dichloromethane, reacting overnight, extracting mixture with ammonium chloride solution, washing with dichloromethane, mixing resulting organic solvent layer, drying over anhydrous magnesium sulfate, filtering and distilling under reduced pressure, recrystallizing crude product with dichloromethane, dissolving recrystallized product in methanol and trifluoroacetic acid, reacting at room temperature for 7-9 hours, removing solvent by steaming, extracting with ethyl acetate for many times, vaccum extracting by anhydrous sodium sulfate, and vacuum drying to obtain 4-((4-(4-(-(4-aminophenyl)diazenyl)benzamido)phenyl)diazenyl)benzenesulfonic acid, and (iii) dissolving 4-((4-(4-(-(4-aminophenyl)diazenyl)benzamido)phenyl)diazenyl)benzenesulfonic acid and sodium nitrite in deionized water, then adding into hydrochloric acid solution under ice-cooling, and reacting for 1-2 hours to obtain diazonium salt solution, adding diazonium salt solution into reduced graphene oxide aqueous solution, reacting under ice bath for 8-10 hours, then reacting at room temperature for 24-48 hours, repeatedly washing with deionized water and dichloromethane until filtrate did not absorb peaks in ultraviolet spectrum, and drying to obtain final product.