Sb‐Doped SnO2 Nanorods Underlayer Effect to the α‐Fe2O3 Nanorods Sheathed with TiO2 for Enhanced Photoelectrochemical Water Splitting

Abstract Here, a Sb‐doped SnO 2 (ATO) nanorod underneath an α‐Fe 2 O 3 nanorod sheathed with TiO 2 for photoelectrochemical (PEC) water splitting is reported. The experimental results, corroborated with theoretical analysis, demonstrate that the ATO nanorod underlayer effect on the α‐Fe 2 O 3 nanorod sheathed with TiO 2 enhances the PEC water splitting performance. The growth of the well‐defined ATO nanorods is reported as a conductive underlayer to improve α‐Fe 2 O 3 PEC water oxidation performance. The α‐Fe 2 O 3 nanorods grown on the ATO nanorods exhibit improved performance for PEC water oxidation compared to α‐Fe 2 O 3 grown on flat fluorine‐doped tin oxide glass. Furthermore, a simple and facile TiCl 4 chemical treatment further introduces TiO 2 passivation layer formation on the α‐Fe 2 O 3 to reduce surface recombination. As a result, these unique nanostructures show dramatically improved photocurrent density (139% higher than that of the pure hematite nanorods).