Transparent and conductive reduced graphene oxide/silver nanoparticles multilayer film obtained by electrical self-assembly process with graphene oxide sheets and silver colloid

The aim of this study is to fabricate transparent and conductive reduced graphene oxide/silver nanoparticles (RGO/Ag NPs) multilayer film by means of an electrostatic self-assembly method. In order to adsorb Ag NPs onto the surface of graphene oxide (GO) sheet easily, the stable and monodispersed Ag NPs/polyelectrolyte-poly(diallyldimethylammonium chloride) (PDDA) colloid was prepared firstly via liquid-phase reduction method, which can be used as a polycation solution in the assembly process. Through the thermal annealing, the GO film was reduced to an RGO film and the Ag NPs grew, leading to the formation of RGO film decorated by Ag NPs with large size and hemisphere-like shape. This structure can improve both optical and electrical properties of RGO film. Results indicated that high density, uniformly sized and well-distributed Ag NPs with hemisphere shape and an average particle size of 85 nm were decorated on the surface of the RGO film and also between the RGO films. The atomic ratio of Ag in RGO/Ag NPs film was 0.6%, which was much higher than that in the GE-Ag film we reported recently, obtained using AgNO3 solution. The transmittance and the sheet resistance of 4-layer RGO/Ag NPs film reached 89.2% and 8.3 k Omega square(-1), respectively.