MRS Meetings and Events


EN02.12.02 2023 MRS Spring Meeting

Bismuth Oxyiodide as a Nontoxic, Air-Stable Perovskite-Inspired Material for Energy Harvesting and Solar Fuels

When and Where

Apr 13, 2023
4:00pm - 4:15pm

Moscone West, Level 2, Room 2002



Robert Hoye1

University of Oxford1


Robert Hoye1

University of Oxford1
Although halide perovskites have taken the photovoltaics field by storm, concerns over the toxic and easily accessible lead content have prompted a search for lead-free alternatives. Bismuth-based compounds have particularly gained attention, owing to their electronic similarities to lead, but advantages of being free from the same toxicity limitations [1]. This talk focuses on our recent work on one of these materials: BiOI.<br/><br/>BiOI is not a perovskite, but replicates important features of the electronic structure of lead-halide perovskites that are believed to be conducive to defect tolerance. We show through computations and experiment that BiOI indeed tolerates the dominant vacancy and anti-site defects. Whilst the bandgap of BiOI (1.9 eV) is too wide for single-junction photovoltaics, we show that it is optimal for indoor light harvesting for sustainably powering Internet of Things (IoT) devices [2], and also suitable for solar energy harvesting as a photocathode for water splitting [3]. In the latter work, we develop a device structure that improves the operational stability of BiOI photocathodes from minutes to months, and combine these devices with BiVO<sub>4</sub> photoanodes to realise the first demonstration of all-oxide-based bias-free syngas production [3]. We also show this device structure to be beneficial for other novel halide photocathodes, such as lead-halide perovskites [4]. We finish off with a discussion of the key factors limiting charge-carrier transport and Urbach energies in BiOI, and how these could be overcome by tuning the composition and structure of this material.<br/><br/><br/>[1] Ganose, Scanlon, Walsh, Hoye*, Nat. Commun., 2022, 13, 4715<br/>[2] Peng, Huq, Mei, … Hoye*, Pecunia*, Adv. Energy Mater., 2020, 11, 2002761<br/>[3] Andrei, Jagt, …, Driscoll*, Hoye*, Reisner*, Nat. Mater., 2022, 21, 864<br/>[4] Andrei, <i>et al.</i>, Nature, 2022, 608, 518


electron-phonon interactions

Symposium Organizers

Eric Colegrove, National Renewable Energy Laboratory
Jessica de Wild, imec
Byungha Shin, Korea Advanced Institute of Science and Technology
Colin Wolden, Colorado School of Mines

Publishing Alliance

MRS publishes with Springer Nature