Comparative study of α-Fe2O3 films prepared by electrodeposition and spray pyrolysis methods as photoanode

Photoelectrochemical (PEC) water splitting using solar energy offers a clean and sustainable approach for the production of renewable hydrogen with less carbon footprint. Hematite is one of the promising materials, which is being considered as photoanode for this application. Accordingly, in this study, alpha-Fe2O3 films deposited by the electrodeposition and spray pyrolysis methods were investigated as photoanodes for PEC water splitting. X-ray diffraction, scanning electron microscopy and UV-Vis spectroscopy techniques were carried out to study the structural, morphological and optical characteristics of the hematite films, respectively. Moreover, the PEC performance and electrical properties of the films were examined by the linear sweep voltammetry under chopped illumination and electrochemical impedance spectroscopy, respectively. The results indicated that the photocurrent density of the electrodeposited film increased by twofold over the spray pyrolysed counterpart. The higher performance of the electrodeposited film was caused by a combination of the higher surface area, more visible light absorption, less charge transfer resistance and higher charge carrier density.