Nasejje, StellaMukhokosi, Emma PanziDiale, M. (Mmantsae Moche)Velauthapillai, Dhayalan2024-11-072024-11-072024-09Nasejje, S., Mukhokosi, E.P., Diale, M. et al. Device architectures for photoelectrochemical water splitting based on hematite: a review. Discover Materials 4, 44 (2024). https://doi.org/10.1007/s43939-024-00112-7.2730-7727 (online)10.1007/s43939-024-00112-7http://hdl.handle.net/2263/98969DATA AVAILABILITY : No datasets were generated or analysed during the current study.Hydrogen production by photoelectrochemical (PEC) water splitting is a sustainable means that can avert the effects of global warming caused by fossil fuels. For decades, a suitable semiconductor that can absorb solar radiation in the visible region has been a focal research question. Hematite has a theoretical Solar-To-Hydrogen efficiency of 15% which is higher than the 10% benchmark for PEC water splitting. Despite being cheap, chemically stable, and bearing a desired band gap, hematite has not reached this projection due to challenges like band edge mismatch, short hole diffusion length and charge recombination. Various articles have shown hetero-structuring is a reliable solution to some challenges due to enhanced spectral range, enhanced carrier mobility, strong built-in electric field and thus increase in efficiency. However, these articles lack scientific rationale on the performance of hematite and its hetero-structures on different substrates, which is the basis for this review. Our analysis suggests that hetero-structure improves hematite’s PEC performance due to increased spectral range, enhanced carrier mobility and built-in electric field. This review article is organized as follows: a brief PEC background, performance parameters, Physical and Crystallographic properties of hematite, device configurations, performance of hematite and its hetero-structures on different substrates.en© The Author(s) 2024. Open Access. This article is licensed under a Creative Commons Attribution 4.0 International License.Photoelectrochemical (PEC)Device architectureHematiteWater-splittingFossil fuelsSDG-07: Affordable and clean energyArticle