Compact hematite buffer layer as a promoter of nanorod photoanode performances

The effect of a thin alpha-Fe2O3 compact buffer layer (BL) on the photoelectrochemical performances of a bare alpha-Fe2O3 nanorods photoanode is investigated. The BL is prepared through a simple spray deposition onto a fluorine-doped tin oxide (FTO) conducting glass substrate before the growth of a alpha-Fe2O3 nanorods via a hydrothermal process. Insertion of the hematite BL between the FTO and the nanorods markedly enhances the generated photocurrent, by limiting undesired losses of photogenerated charges at the FTO parallel to electrolyte interface. The proposed approach warrants a marked improvement of material performances, with no additional thermal treatment and no use/ dispersion of rare or toxic species, in agreement with the principles of green chemistry.