▎ 摘　　要

NOVELTY - Preparing graphene film involves assembling graphene oxide nano sheets into film by wet method, drying and activating carbon at a high temperature of 1600-2000℃ for 30-240 minutes, which results in interlayer cross-linking between the upper and lower graphene oxide nanosheets at the defect to obtain high vertical graphene membrane with thermal conductivity ≥10 Watts (W)/mK. USE - Graphene film is used in the fields of electronic devices, heat pipe systems, high-temperature heat protection (claimed). ADVANTAGE - The method uses the internal defect of the oxidized graphene nanosheet to realize carbon-carbon interlayer cross-linking at high temperature, building the phonon transmission bridge between vertical direction layer to give graphene film with excellent vertical heat-conducting performance. The electronic transmission and shear resistance between the graphene layer is greatly improved, exhibiting application potential in the high power electronic element and high power device and high heat management field, by the formation of interlayer covalent bond.