TiO2 nanorod array film decorated with rGO nanosheets for enhancing photocatalytic and photoelectrochemical properties

A well-aligned TiO2 nanorod array film decorated with reduced graphene oxide(rGO/TNR) was constructed on fluorine-doped tin oxide (FTO) via a one-pot hydrothermal route with the aim of improving the photocatalytic and photoelectrochemical performances. The optimal ratio of components was investigated by changing the GO content that was added to the TiO2 precursor solution. The structure, morphology, composition, optical, photocatalytic and photoelectrochemical properties of the rGO/TNR films were investigated in detail. The resulting rGO/TNR films had a unique microstructure, apparent red shift of the absorption edge and low recombination rate of photoinduced charge carriers. For the degradation of methylene orange (MO) under UV light, the 5 wt%-rGO/TNR film exhibited the best photogradation efficiency of 95.8% in 120 min compared to bare TNR, which had a photogradation efficiency of 41.4%. Moreover, the 5 wt%-rGO/TNR film also showed the highest photocurrent of 110 μA/cm2, which was 6 times higher than that of bare TNR (16 μA/cm2). The excellent performance of the rGO/TNR film may be caused by the synergistic effect of the extended photoresponse range, high adsorption of target molecules and effective photogenerated electron-hole separation via rGO nanosheets as electron collectors and transporters.