▎ 摘　　要

NOVELTY - A composite heat storage material comprises azo/graphene metal coordination compound. The azo/graphene metal coordination compound has magnesium-containing structure (I). USE - Composite heat storage material. DETAILED DESCRIPTION - A composite heat storage material comprises azo/graphene metal coordination compound. The azo/graphene metal coordination compound has magnesium-containing structure of formula (I). A = group of formula (a). An INDEPENDENT CLAIM is included for preparation of the composite heat storage material, which involves hydrothermally reacting graphene oxide aqueous solution at 60-160 degrees C for 2-48 hours to obtain reduced graphene oxide aqueous solution, preparing hydrochloric acid solution of azobenzene p-sulfamate and hydrochloric acid solution of sodium nitrite, dripping hydrochloric acid solution of sodium nitrite to hydrochloric acid solution of azobenzene p-sulfamate at 0-5 degrees C to form diazonium salt, adding diazonium salt to reduced graphene oxide aqueous solution, reacting, washing product with water, N,N-dimethylformamide and ethanol until filtrate has no characteristic azo absorption peak in UV absorption detection, drying to obtain azo/graphene composite material, dispersing in N,N-dimethylformamide, dissolving metal compound in N,N-dimethylformamide, adding N,N-dimethylformamide solution of metal compound to N,N-dimethylformamide solution of azo/graphene, taking precipitate out, washing metal ions not involved in coordination, and drying obtained product.