▎ 摘　　要

NOVELTY - The method involves making (S1) nitrate mixed solution to react with citric acid solution to generate nanoparticle catalyst with high specific surface area. The sodium nitrate and 1 g of flake graphite powder are added (S2) to 23 ml of concentrated sulfuric acid with a mass fraction of 98% to form a mixed solution, and 3 g of potassium permanganate and hydrogen peroxide are added to react to generate graphene oxide. The graphene composite catalyst is prepared (S3). The graphene oxide in the mixed solution is reduced to graphene to generate the graphene which is flocculant black floating or sediment in the mixed solution of a reducing agent with a mass fraction of 50% which is added to react. The graphene is filtered, washed for multiple times and freeze-dried to obtain a graphene composite material. USE - Preparation method of graphene-based catalyst for air electrode for fuel cells, metal-air batteries and metal hydride-air batteries. ADVANTAGE - The graphene composite catalyst realizes a good catalytic activity due to the larger specific surface area and higher electronic conductivity, such that the preparation method is simple, the synthesis cost is low, and the reproducibility is good, and is easy to realize industrial production. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a graphene-based catalyst for air electrode. DESCRIPTION OF DRAWING(S) - The drawing shows a flow chart of a preparation method of graphene-based catalyst for air electrode. (Drawing includes non-English language text) Step for making nitrate mixed solution to react with citric acid solution to generate nanoparticle catalyst with high specific surface area (S1) Step for adding sodium nitrate and flake graphite powder of concentrated sulfuric acid with a mass fraction to form a mixed solution, and potassium permanganate and hydrogen peroxide are added to react to generate graphene oxide (S2) Step for preparing graphene composite catalyst (S3)