▎ 摘　　要

NOVELTY - A preparation method of high crystallinity graphene nanobelt, involves (1) taking commercial multi-walled carbon nanotubes, adding mixed acid solution of concentrated sulfuric acid and concentrated nitric acid, stirring, ultrasonically treating, diluting, filtering, cleaning, freezing and drying to obtain acid-treated carbon nanotubes, (2) heat-treating the carbon nanotubes to obtain nitrogen-doped carbon nanotubes, (3) dispersing the nitrogen-doped carbon nanotubes in ethanol solution to obtain dispersion liquid, forming a sample film on a surface of the glassy carbon electrode, taking a glassy carbon electrode as a working electrode, a platinum electrode as a counter electrode, and a saturated calomel electrode as a reference electrode, and electrochemically de-linking carbon nanotubes, and (4) taking out glassy carbon electrode, washing sample film on a surface of carbon electrode, dispersing sample film in N-methyl-2-pyrrolidone, ultrasonically treating, and centrifuging. USE - Preparation method of high crystallinity graphene nanobelt for use as oxygen reduction catalyst (claimed) and for preparing fuel cell cathode catalyst. ADVANTAGE - The cost of the graphene nanobelt is reduced. The experimental steps of the graphene nanobelt are simplified. The graphene nanobelt has high yield and crystallinity, and excellent catalytic performance. DETAILED DESCRIPTION - A preparation method of high crystallinity graphene nanobelt, involves (1) taking commercial multi-walled carbon nanotubes, adding mixed acid solution of concentrated sulfuric acid and concentrated nitric acid, stirring uniformly, using an ultrasonic wave cleaning machine for ultrasonic treatment to remove metal impurities, diluting, filtering and cleaning, freezing and drying to obtain acid-treated carbon nanotubes, (2) performing high temperature heat treatment on the carbon nanotubes in a mixed atmosphere of ammonia gas and argon gas to obtain nitrogen-doped carbon nanotubes, (3) dispersing the nitrogen-doped carbon nanotubes in ethanol solution to obtain dispersion liquid, forming a sample film on a surface of the glassy carbon electrode by using the drop-coating method, taking a glassy carbon electrode as a working electrode, a platinum electrode as a counter electrode, and a saturated calomel electrode as a reference electrode, and electrochemically de-linking the carbon nanotubes in dilute sulfuric acid solution, and (4) taking out the glassy carbon electrode after melting the chain, washing the sample film on a surface of the glassy carbon electrode orderly using deionized water and N-methyl pyrrolidone, dispersing the sample film in N-methyl-2-pyrrolidone, ultrasonically treating in an ice bath for increasing the melting degree, and centrifuging at high speed. An INDEPENDENT CLAIM is included for use of the high crystallinity graphene nanobelt as oxygen reduction catalyst.