Impact of Graphene oxide (GO) and reduced Graphene Oxide (rGO) on the TiO2 thin film composite (TiO2: GO/ rGO) photoanodes

Graphene and its derivatives have several advantages such as large surface area, great chemical stability, high transmittance, and good electrical conductivity, which are the fundamental qualities required by photovoltaic industries. GO and rGO are mixed in various proportions ranging 0 wt.% - 15 wt.% to spin coat TiO2: GO/rGO composite thin films. The effect of graphene oxide and reduced graphene oxide on the performance the TiO2 based composite photoanodes are obtained. A tetragonal anatase phase of TiO2 was confirmed by the XRD analysis. The calculated crystallite size decreases with lower concentrations of GO and rGO but starts to increase for higher concentrations. The spectrophotometer studies have confirmed that the optical bandgap of pure TiO2 films is decreased on doping with GO and rGO. The SEM analysis have confirmed that the surface is tightly packed with the uniformly distributed grains, and they are very compact.