Polyacrylonitrile coupled graphite oxide film with improved heat dissipation ability

Graphene film has potential to act as an excellent heat dissipation material. However, its thermal conductivity suffers from some limitations, including small graphene lateral sizes and low production efficiency from a practical viewpoint. To solve these issues, we propose an industrially viable protocol to synthesize homogeneously oxidized graphite oxide (GtO) with large lateral sizes and easy-purifying features. We employ polyacrylonitrile (PAN) as a coupling agent to repair the defects on GtO sheets and link these sheets together during the annealing treatment. The graphitized GtO/10%PAN film (g-GtO/10%PAN) shows excellent thermal and electrical properties, with an in-plane thermal conductivity of 1629.24 +/- 43.88 W m(-1) K-1 and an electrical conductivity of 9645.29 +/- 199.44 S cm(-1). Furthermore, it also exhibits outstanding flexibility; the original thermal conductivity can be maintained after 20,000 times bending. The g-GtO/10%PAN film offers an alternative to replace commercially used graphitized polyimide (PI) film. Our research provides a general method for the fabrication of high quality graphene film. (C) 2018 Elsevier Ltd. All rights reserved.