Enhanced Photoelectrochemical Water Oxidation Performance of Fe<sub>2</sub>O<sub>3</sub> Nanorods Array by S Doping

As a promising candidate for photoelectrochemical (PEC) water oxidation, the photoelectrochemical water splitting efficiency of hematite (Fe<sub>2</sub>O<sub>3</sub>) is limited by its low electron mobility. In this work, we report a new strategy for great enhancement of PEC water oxidation activity on Fe<sub>2</sub>O<sub>3</sub>. The S-doped Fe<sub>2</sub>O<sub>3</sub> (S:Fe<sub>2</sub>O<sub>3</sub>) nanorods array on a Ti plate shows a substantially increased photocurrent density of 1.42 mA cm<sup>–2</sup> at 1.23 V vs RHE in 1.0 M NaOH under simulated sunlight irradiation (AM 1.5G, 100 mW cm<sup>–2</sup>), 2.45 times that of Fe<sub>2</sub>O<sub>3</sub> counterpart (0.58 mA cm<sup>–2</sup>). Both density functional theory calculations and experimental measurements verify that the superior activity is contributed to the enhanced electron mobility after S doping. This study offers an attractive photoanode in water-splitting devices for solar hydrogen production application.