▎ 摘　　要

NOVELTY - The preparation method of flexible highly conductive graphene film involves (i) freezing oxidized graphene dispersion at -50 to -20 degrees C for 10-24 hours, and freeze-drying for 72-100 hours to obtain an oxidized graphene sponge, (ii) reducing oxidized graphene sponge with hydrazine reducing agent steam, (iii) heat treating in an inert gas protection atmosphere at 1000-5000 degrees C for 0.5-2 hours, (iv) vacuumizing to 10-400 Pa, and pressure treating at 30-500 MPa for 1 minute. USE - Preparation of flexible highly conductive graphene film (claimed). ADVANTAGE - The method enables the preparation of flexible highly conductive graphene film by simple process at low cost in a controlled manner with high productivity, conductivity, and density.