▎ 摘　　要

Large area multilayered graphene films were prepared by chemical vapour deposition using copper foils as substrate. We found that reaction temperature seriously affected the defects of the film but did not change the size, while reaction time dominated the defects and size. We further explained the surface deposition growth of the graphene film, and ascribed the growth of amorphous carbon to the reduction of copper catalysis. In addition, the graphene film showed improved electrocatalytic effect on hydrogen peroxide. This study opens an avenue for large area preparation of high quality graphene film for its electrochemical applications.