▎ 摘　　要

NOVELTY - Preparation of graphene/hollow carbon nanosphere includes mixing ammonia, water and ethanol, dropping tetraethyl orthosilicate and ethanol mixture, adding KH-550 silane coupling agent, stirring, washing with water and with ethanol, and vacuum-drying to obtain silane coupling agent-modified silica nanoparticles; adding water, sonicating, adding graphene oxide solution, stirring, filtering, washing with water, and vacuum-drying to obtain silica nanoparticles/graphene oxide; and adding ammonia, water and ethanol, sonicating, adding resorcinol and formaldehyde solution, reacting, and drying. USE - Method for preparation of graphene/hollow carbon nanosphere (claimed) used as supercapacitor electrode material. ADVANTAGE - The product has higher specific capacity and better cycle stability. DETAILED DESCRIPTION - Preparation of graphene/hollow carbon nanosphere comprises: (A) mixing ammonia, water and ethanol at volume ratio of 1:2-3:16-18 to obtain first solution; mixing tetraethyl orthosilicate and ethanol at ratio of 1:6-8 to obtain second solution, dropping into first solution at volume ratio of 1:4-6, adding 1 wt.% KH-550 silane coupling agent, stirring for 10-12 hours, washing with water and with ethanol, and vacuum-drying to 50-80 degrees C to obtain silane coupling agent-modified silica nanoparticles; (B) adding water at mass ratio of 1:100-150, sonicating for 1-2 hours, adding 1 mg/mL graphene oxide solution at mass ratio of 1:20-40, stirring, filtering, washing with water, and vacuum-drying to 50-80 degrees C to obtain silica nanoparticles/graphene oxide; (C) adding ammonia, water and ethanol at ratio of 1:150-250:60-80:2-9, sonicating for 1-2 hours, adding resorcinol and formaldehyde solution at mass ratio of 1:1.5-1.8, stirring for 24 hours, putting into PTFE-lined stainless steel autoclave, hydrothermally reacting to 100 degrees C for 24 hours, and drying to 60-100 degrees C for 6-12 hours to obtain silica nanoparticles/graphene oxide-containing polymer nanosphere; and (D) placing into tube furnace, calcining to 600-1000 degrees C at heating rate of 2-10 degrees C/minute, naturally cooling, washing with 3 mol/L sodium hydroxide solution to remove silica, washing with water, and drying. The resorcinol and silica nanoparticles/graphene oxide have mass ratio of 1:2-5. The sodium hydroxide solution and silica have mass ratio of 12:1. The graphene oxide solution is prepared by putting 2 g natural graphite powder and 1 g sodium nitrate into a flask, ice bath stirring to 0-4 degrees C, adding 46 mL concentrated sulfuric acid and 6 g potassium permanganate, stirring for 2 hours, transferring to water bath, stirring to 35 degrees C for 2 hours, adding 92 mL deionized water, stirring to 90 degrees C for 15 minutes, adding 280 mL deionized water and 9 mL hydrogen peroxide, washing with 2.1 wt.% dilute hydrochloric acid, washing with deionized water until neutral, and ultrasonically dispersing in water.