BiMn2O5: A stable solar fuels photoanode with ideal band gap
Newhouse, P. F., Reyes-Lillo, S. E., Li, G., Zhou, L., Shinde, A., Guevarra, D., Suram, S. K., Soedarmadji, E., Richetr, M. H., Qu, X., Persson, K., Neaton, J. B., Gregoire, J. M. Discovery and Characterization of a Pourbaix Stable, 1.8 eV Direct Gap Bismuth Manganate Photoanode. Chem. Mater, DOI: 10.1021/acs.chemmater.7b03591 (2017).
Combining high throughput experimentation with theory enabled discovery of a unique solar fuels photoanode with strong visible light absorption and remarkable stability.
Significance & impact
Semiconductors with a band gap in the visible range are typically unstable at water oxidation potentials, making this 1.8 eV direct-gap photoanode an unprecedented discovery.
The discovery was made in an inkjet-printed combinatorial library where BiMn2O5 was revealed as the active photoanode whose alloy with Sm improves photoactivity.
The Pourbaix-stable region extends 13 pH units at 1.23 vs RHE
The electronic structure resembles that of BiVO4 with similar valence band hybridization and V d states replaced by Mn d.