Photoelectrochemical activity of ZnFe2O4 modified α-Fe2O3 nanorod array films

Abstract

ZnFe₂O₄ modified α-Fe₂O₃ nanorod array films were successfully synthesized by aqueous solution growth followed by a spin coating process and studied for photoelectrochemical (PEC) water splitting under solar light. Through the spin coating process, ZnFe₂O₄ was found mainly to exist at the top surface of the α-Fe₂O₃ nanorod arrays. After being modified by ZnFe₂O₄, the α-Fe₂O₃ nanorod film was identified as a suitable surface treatment, and showed an increased photocurrent density when used as the photoanode. It was demonstrated that ZnFe₂O₄ increased the charge carrier density and acted as the oxidation cocatalyst. These results suggested that surface treatment by ZnFe₂O₄ should be a practical strategy to improve the efficiency of α-Fe₂O₃ or other metal oxide photoanodes for PEC solar fuel conversion.