Quantitative evaluation of electrophoretic deposition kinetics of graphene oxide

The electrophoretic deposition (EPD) technique is an attractive approach for development of graphene and graphene oxide (GO) films for a variety of applications. However, in order to establish the influence of the EPD parameters on the properties of the deposited films, a deeper investigation of the fundamental GO-EPD kinetics is required. Previous studies have reported a simultaneous anodic reduction of GO flakes during EPD, complicating the kinetics and process control. Therefore, in this study, low voltages were used to prevent significant GO reduction during EPD, as confirmed by XPS and FTIR. Accordingly, the GO-EPD kinetics was established as a function of deposition time and voltage, accompanied by microscopic characterization of the deposited films. The experimental results show that the deposition follows a linear growth law, in good agreement with the predictions of Hamaker's law. Comparisons of optical absorbance and profilometry provide estimates of (reduced) GO deposition rate, extinction coefficient, and density.