Enhanced photoelectrochemical water splitting performance of hematite photoanodes by hybrid microwave annealing process

Abstract

This work describes the preparation of hematite photoanode with suppressed both bulk and surface charge recombination rates by combined hydrothermal synthesis and hybrid microwave annealing (HMA) process. Three-dimensional branches like morphology were obtained for HMA processed photoanoanode. The obtained HMA processed photoanode shows enhanced PEC performance as compared with photoanode treated by a conventional annealing process with a photocurrent density of 0.32 mAcm−2 at 1.23 V vs RHE. Optical absorbance, electrochemical impedance spectroscopy, Mott-Schottky and hole scavenger oxidation measurements were demonstrated that the suppresses charge carriers recombination rates in bulk and surface state of hematite photoanode and enhances the donor density, thereby the PEC water splitting performance was enhanced. The enhanced PEC water splitting performance HMA processed hematite could be attributed to well define branches like morphology with high crystallinity and increased optical absorption.