Enhancement of photoelectrochemical response by Au modified in TiO2 nanorods

Abstract

We report on the design and synthesis of a novel Au/TiO2/Au heterostructure and its implementation as a photoanode for photoelectrochemical (PEC) application. The Au/TiO2/Au heterostructure was produced by assembling Au nanoparticles and TiO2 nanorods (NRs) onto FTO substrate, followed by electrodepositing Au nanoparticles on the TiO2NRs. Field emission scanning electron microscopy (FESEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and electrochemical methods were adopted to characterize the prepared photoanodes. Compared to the system involving Au nanoparticles directly linked to TiO2, this Au/TiO2/Au heterostructure exhibits significant improved photoresponse as a photoanode, as demonstrated good performance in PECs. This study illustrates the importance of pre-deposited Au underlayers in influencing PEC properties of hybrid assembled nanostructures. As the Au/TiO2NRs/Au photoanodes are easily fabricated and highly stable, Au/TiO2NRs/Au can serve as a good substitution for TiO2 in a variety of solar energy driven applications including PEC water splitting, photocatalysis, and solar cells.