Microwave-Assisted Hydrothermal Synthesis of Fe-Doped TiO2 Photoanode for Photocatalytic Hydrogen Evolution

Abstract

One-dimensional TiO2 nanostructures like nanotubes, nanowires, and nanorods have received huge attention due to their photocatalytic hydrogen-generating ability. However, its wide band gap and high charge carrier recombination rate hampered the efficiency with which it converts solar energy into hydrogen. To improve this application, metallic doping employing a quick and easy synthesis method should be proposed. In this study, we report on the microwave-assisted hydrothermal synthesis of iron-doped TiO2 nanowires on an FTO substrate. The formation of TiO2 nano-wires was validated by structural and morphological analysis carried out using XRD and SEM imaging respectively. EDX was employed to provide a breakdown of their chemical composition to verify the presence of dopants in the samples. The impact of Fe-doping on optical and photoelectrochemical properties was studied. Electrochemical impedance spectroscopy was used to determine the mechanisms behind charge accumulation and charge transfer properties. The Mott-Schottky plot was used to examine the donor density and the flat-band potential of the pristine and Fe-doped TiO2 samples.