Impact of preparation method of TiO₂-RGO nanocomposite photoanodes on the performance of dye-sensitized solar cells

In this work, a comparative study has been performed on two ex-situ and one in-situ doping of titania photoanodes with reduced graphene oxide. The presence of finely dispersed reduced graphene oxide facilitates electron transport and reduces electron-hole recombination resulting in a better performance of doped titania photoanodes. It was found that in-situ doping, i.e. introduction of graphene oxide in solution together with titania precursor was the most performant case of graphene doping. This result was obvious by studying dye-sensitized solar cells based on such doped photoanodes but was also and mainly analytically demonstrated by subjecting the obtained materials to characterization by several techniques, including thermal and N₂ adsorption-desorption analysis, SEM and TEM microscopy and XRD, XPS, Raman, UV–vis, Photoluminescence and Electrochemical Impedance Spectroscopy.