Nanoflower like SnO2-TiO2 nanotubes composite photoelectrode for efficient photocathodic protection of 304 stainless steel

In this study, titanium dioxide nanotube arrays (TiO2-NTs) were prepared on titanium plates through a two-step anodization method and then the SnO2 nanoparticles were deposited onto TiO2-NTs by electrodeposition method to produce SnO2-TiO2-NTs. The electrodeposition time has a great influence on the photoeletrochemical (PEC) performance of SnO2-TiO2-NTs composite photoelectrode. The photocurrent density of SnO2-TiO2-NTs electrode increased up to 4 times as compared to pristine TiO2-NTs photoelectrode. Furthermore, open circuit potential and tafel curves were measured to evaluate the photocathodic protection properties of SnO2-TiO2-NTs. The corrosion potential dropped to -730 mV and the corrosion current density reached to 259.8 μA/cm−2. The results indicate that SnO2 deposition into the TiO2-NTs photo-electrode is a simple and effective way to protect stainless steel (304SS) from corrosion.