▎ 摘　　要

NOVELTY - Preparing core-shell cobalt sulfide-nitrogen-doped graphene oxide nano composite material comprises e.g. (i) carrying out hydrothermal method of cobalt sulfide growth solution, (ii) mixing core-shell cobalt sulfide nanoparticle and aminopropyltriethoxysilane in solvent, and stirring, (iii) placing 3-aminopropyltrimethoxysilane-modified core-shell cobalt sulfide nanoparticle in nitrogen-doped graphene precursor fluid, performing hydrothermal method to obtain nitrogen-doped graphene-coated core-shell cobalt sulfide nanoparticles composite material. USE - The composite material is useful in field of hydrogen evolution (claimed). ADVANTAGE - The composite material has excellent mechanical flexibility, electro-catalysis property and redox catalytic activity, stability and exhibits low starting potential, low overpotential and high cycle stability. DETAILED DESCRIPTION - Preparing core-shell cobalt sulfide-nitrogen-doped graphene oxide nanocomposite material comprises (i) carrying out hydrothermal method of cobalt sulfide growth solution to obtain core-shell cobalt sulfide nanoparticle, (ii) mixing core-shell cobalt sulfide nanoparticle and aminopropyltriethoxysilane in solvent, and stirring to obtain aminopropyltriethoxysilane modified core-shell cobalt sulfide nanoparticle, (iii) placing 3-aminopropyltrimethoxysilane-modified core-shell cobalt sulfide nanoparticle in nitrogen-doped graphene precursor fluid, performing hydrothermal method to obtain nitrogen-doped graphene-coated core-shell cobalt sulfide nanoparticles composite material, where nitrogen-doped graphene precursor solution comprises graphene oxide, aqueous ammonia and sodium hydroxide. An INDEPENDENT CLAIM is also included for core-shell cobalt sulfide-nitrogen-doped graphene oxide nanocomposite material obtained by above method.