Performance, comprehension and applications of hematite-based photoanodes in PEC water splitting

The world is facing significant energy challenges, and renewable hydrogen production has emerged as a promising solution. Water splitting by photoelectrochemical cells (PEC) is one of the popular methods used for hydrogen production. For this process, hematite (α − Fe2O3) is emerging as a suitable candidate (as photoanodes) because of its relative abundance, stability and wide bandgap ranging from 1.9 to 2.2 eV that is suitable for solar absorption. This review provides a critical analysis about the performance, comprehension, and applications of α − Fe2O3 as a photoanode for water splitting. Over the years, there has been a concerted effort to enhance the performance of α − Fe2O3 photoanodes. It resulted in various strategies being developed to synthesize and modify the photoanode, resulting in significant advancements. The primary focus is given to designing of a nanostructure, that is doped with suitable elements, modified with the help of co-catalysts and heterostructure formation.