▎ 摘　　要

NOVELTY - The method involves after preparing a calcining reactant precursor containing urea, bacterial cellulose and cobalt salt. The certain quality of bacterial cellulose film is repeatedly rinsed with deionized water to obtain a clean bacterial cellulose film. The cleaned bacterial cellulose film is immersed in the mixed solution of urea and cobalt salts, until the mixed solution is completely dissolved and uniformly dispersed. The mass ratio of the folded bacterial cellulose to urea is provided between 1:1 and 1:40. The mass ratio of cobalt element to bacterial cellulose is provided in the ration of 1:3-1:12.5. The mixed solution is completely frozen into a solid in a refrigerator. The frozen sample is freeze-dried to obtain an aerogel of bacterial cellulose, pink flocculent urea and cobalt salt mixture. The obtained aerogel is placed in a tube furnace, and is calcined at a high temperature of 700degreesC-900degreesC for 1 hour. A black carbon aerogel is obtained. USE - Method for preparing metal cobalt nanoparticle nitrogen-doped graphene and carbon nano-fiber composite material used as catalyst material (claimed) for preparing hydrogen by electrocatalysis hydrolysis. ADVANTAGE - The metal cobalt nanoparticle nitrogen-doped graphene and carbon nano-fiber composite material promotes the internal electron redistribution of the metal and semiconductor hetero-junctions in the material through the Mott-Schottky effect. The metal cobalt nanoparticle nitrogen-doped graphene and carbon nano-fiber composite material exhibits a good electrocatalytic effect as a catalyst in the hydrogen evolution reaction (HER). DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of transmission electron microscopy (TEM) image of synthetic metal cobalt nanoparticle nitrogen-doped graphene and carbon nano fiber composite material.