Comparing the electrophoretic deposition process of graphene oxides synthesized through different methods

Graphene oxide (GO) is synthesized through two different chemical methods, namely modified improved method (MIM) and modified Hummers method (MHM). Electrophoretic deposition of GO obtained from those methods is performed on the Fluorine doped tin oxide glass substrates by dispersing GO sheets in acetonitrile and applying voltage. UV–vis and Raman spectroscopies show that pristine graphite is less oxidized in the MIM. However, X-ray diffraction patterns indicate that d-spacing of GO sheets is more increased in the MIM (d-spacing of 0.94 nm vs. 0.77 nm). Also, Fourier-transformed infrared spectroscopy reveals that GO synthesized through the MIM contains more C=O functional groups on its surface. As a result, current density-time diagrams and field emission scanning electron microscope (FESEM) cross-sectional images of electrophoretically deposited GO films are indicative of higher average deposition rate in the MIM compared to MHM (~ 5.1 nm/s vs. ~ 1.8 nm/s). FESEM images of the two films show that surface roughness of the MIM film is lower than that of MHM film as well. - Highlights: • Graphene oxide (GO) was synthesized through two different chemical methods. • The modified improved method (MIM) led to GO with greater crystallite size. • EPD process of these two kinds of GO was carried out. • GO synthesized by MIM revealed a higher average deposition rate in the EPD process.