Direct and Efficient Preparation of Graphene Transparent Conductive Films on Flexible Poly Carbonate Substrate by Spray-Coating

Owing to the hydrophobic property and heat-labile of flexible substances, it is difficult to prepare graphene transparent conductive films (TCFs) on flexible substrate in a direct and effective way. Here we prepared a good dispersion of water/graphene oxide (GO)/ethanol, and the fabrication of graphene TCFs on flexible poly carbonate (PC) substrate was made by spray deposition of water/GO/ethanol, followed by the reduction of hydriodic acid (HI) fuming method. It can be found that when ethanol was added to GO solution, the drying dynamics of the spraying solvent increased and the problem of wetting property of GO dispersion on the PC could be effectively resolved. HI acid vapour can achieve an effective reduction of the GO film. The reduction effect of HI acid fuming method is more effective in comparation with traditional HI acid immersed method. An increase in spraying concentration can lead to a rise in coverage degree of film and folding degree of surface. 1/500 mg/ml is a relatively appropriate concentration for spray-coating. The thickness of the film was controlled by adjusting the spraying volume of water/GO/ethanol dispersion. The graphene TCFs exhibit a sheet resistance of less than 15.3 k Omega/sq at 74% transmittance.