Se doping: an effective strategy toward Fe2O3 nanorod arrays for greatly enhanced solar water oxidation

Abstract

In this communication, we first report a fast and low-temperature preparation of Se doped Fe₂O₃ (Se-Fe₂O₃) nanorod arrays grown on a Ti plate with superior photoelectrochemical (PEC) performance for water oxidation. The Se-Fe₂O₃ offers a photocurrent density of 1.44 mA cm⁻² at 1.23 V vs. the RHE in 1.0 M NaOH under simulated light (AM 1.5 G, 100 mW cm⁻²) irradiation, 3.13 times that of undoped Fe₂O₃, with a 90 mV cathodic shift of the onset potential. Experimental studies indicate that the superior PEC activity is ascribed to the increased electrical conductivity and carrier density arising from Se doping, which is of great benefit to improve the charge separation efficiency in bulk Se-Fe₂O₃. The present Se-doping offers an attractive approach to fabricate high-performance semiconductor photoanodes for applications.