▎ 摘　　要

NOVELTY - Preparation of nitrogen-doped carbon-graphene-manganese oxide composite material involves ultrasonically dispersing oxidized graphene in water, adding m-phenylenediamine monomer for 5-30 minutes, pouring mixture into flask, heating to 90-100 degrees C for 6-24 hours, cooling, adding potassium permanganate solution, stirring for 3-5 hours, washing, filtering, freeze drying for 20-30 hours to obtain composite material, sintering at 600-800 degrees C for 3-5 hours, ultrasonically dispersing obtained composite material, applying to electrode, and drying to obtain modified composite electrode. USE - Preparation of nitrogen-doped carbon-graphene-manganese oxide composite material for electrocatalytic reduction of oxygen. ADVANTAGE - The nitrogen-doped carbon-graphene-manganese oxide composite material having high specific surface area and electro-catalytic properties is produced. DETAILED DESCRIPTION - Preparation of nitrogen-doped carbon-graphene-manganese oxide composite material involves ultrasonically dispersing oxidized graphene in deionized water, adding m-phenylenediamine monomer for 5-30 minutes, pouring mixture into flask, heating to 90-100 degrees C for 6-24 hours, cooling to room temperature, adding potassium permanganate solution to the reaction solution, stirring for 3-5 hours, washing, filtering, freeze drying for 20-30 hours to obtain composite material, sintering at 600-800 degrees C for 3-5 hours under argon atmosphere, ultrasonically dispersing obtained composite material, applying to electrode, and drying at room temperature to obtain modified composite electrode. The oxygen reduction electrocatalytic activity of the composite is tested by electrochemical workstation, in which modified electrode is set as reference electrode, and potassium hydroxide solution is used as electrolyte. Before the electrochemical test, the solution is purged with nitrogen or oxygen for 30-50 minutes, and resulting solution is used as working electrode. The electrocatalytic activity of the material is evaluated by cyclic voltammetry and cyclic voltammetry. The oxygen reduction potential and the limiting current density ware used to determine the oxygen reduction activity of the material. The stability of composite is determined under the constant potential of -0.3 V for 10000 seconds. The performance of nitrogen-doped carbon-graphene-manganese oxide on the electrocatalytic activity of 0.1M potassium hydroxide (oxygen saturation) and 1 M methanol mixed solution (oxygen saturation) is determined.