Activation of α-Fe₂O₃ Photoanode by Rapid Annealing Process for Photoelectrochemical Water Splitting

Hematite (α-Fe2O3) has been attracted for PEC water splitting applications due to its chemical stability and visible light absorption property. To, further improve the PEC water splitting performance of the α-Fe2O3 photoanode, a new activation process of hybrid microwave annealing (HMA) was taken on. In the present work, an α-Fe2O3 photoanode was synthesized by the companied hydrothermal method and HMA process. The effect of HMA processing time on PEC water splitting performance of the α-Fe2O3 photoanode was investigated. The results showed that a shorter HMA processing time (30 s) of photoanode provides a higher photocurrent density (∼0.74 mAcm−2 at 1.23 V vs RHE) than the photocurrent density (∼0.11mAcm−2at 1.23 V vs RHE) of photoanode processed by longer time (3 min). This result due to the cauliflower-like morphology of α-Fe2O3(30 s) photoanode facilitates the enhanced light absorption thus provides a higher electrical conductivity with suppressed photogenerated charge carrier's recombination rates.