Enhanced photocathodic protection performance of Fe2O3/TiO2 heterojunction for carbon steel under simulated solar light

Abstract Titanium dioxide nano array (TNAs) was successfully modified with Fe 2 O 3 (FTNAs) to enhance the photocathodic protection performance for carbon steel. Fe 2 O 3 as a sensitizer captures large quantities of light photons, resulting in a strong light harvest capability of FTNAs. Meanwhile, the bandgap of FTNAs decreased to 2.26 eV, and the photo-generated current densities were 90 and 400 μA cm −2 for TNAs and FTNAs under simulated solar light illumination, respectively. The narrowed bandgap and the sensitive photoelectric response together contribute to a good photocathodic protection performance of FTNAs, which was confirmed by the electrochemical impedance spectroscopy and electrochemical noise.