▎ 摘　　要

With the rapid evolvement of microelectronic devices, the accompanying high amount of heat should be transferred in time by the thermal management system to ensure the desired performance. The design of the thermal management system that possesses high thermal conductivity with flexibility is still a challenge that needs to be overcome. Here, we propose a two-step liquid-phase repairing method using hydriodic acid to remove the defects from large graphene oxide sheets produced by a modified Hummers method to make the structure intact. Compared to thermally reducing method, our method can work under much lower temperature so that it is easier to apply in mass production with much better energy conservation effects. In our research, transverse dimensions of the graphene oxide sheets with range from 50 to 270 mu m were obtained by a modified Hummers method, which effectively reduces the interlayer thermal resistance; then flexible, highly thermally conductive graphene films can be developed by a two-step liquid-phase repairing method with hydriodic acid. This process produces a flat reduced graphene oxide film with a powder-free surface that is highly thermally conductive and flexible, can be folded at 180 degrees for 1000 times without breaking and has a thermal diffusion coefficient of 1737 mm(2) s(-1). Multifunctional reduced graphene oxide graphene films can easily transfer large amount of heat from miniaturised, densely packed electronics for efficient thermal management.