A1 Journal article (refereed)
Strong absorption and ultrafast localisation in NaBiS2 nanocrystals with slow charge-carrier recombination (2022)
Huang, Y.-T., Kavanagh, S. R., Righetto, M., Rusu, M., Levine, I., Unold, T., Zelewski, S. J., Sneyd, A. J., Zhang, K., Dai, L., Britton, A. J., Ye, J., Julin, J., Napari, M., Zhang, Z., Xiao, J., Laitinen, M., Torrente-Murciano, L., Stranks, S. D., . . . Hoye, R. L. Z. (2022). Strong absorption and ultrafast localisation in NaBiS2 nanocrystals with slow charge-carrier recombination. Nature Communications, 13, Article 4960. https://doi.org/10.1038/s41467-022-32669-3
JYU authors or editors
Publication details
All authors or editors: Huang, Yi-Teng; Kavanagh, Seán R.; Righetto, Marcello; Rusu, Marin; Levine, Igal; Unold, Thomas; Zelewski, Szymon J.; Sneyd, Alexander J.; Zhang, Kaiwen; Dai, Linjie; et al.
Journal or series: Nature Communications
eISSN: 2041-1723
Publication year: 2022
Publication date: 24/08/2022
Volume: 13
Article number: 4960
Publisher: Nature Publishing Group
Publication country: United Kingdom
Publication language: English
DOI: https://doi.org/10.1038/s41467-022-32669-3
Publication open access: Openly available
Publication channel open access: Open Access channel
Publication is parallel published (JYX): https://jyx.jyu.fi/handle/123456789/82859
Abstract
I-V-VI2 ternary chalcogenides are gaining attention as earth-abundant, nontoxic, and air-stable absorbers for photovoltaic applications. However, the semiconductors explored thus far have slowly-rising absorption onsets, and their charge-carrier transport is not well understood yet. Herein, we investigate cation-disordered NaBiS2 nanocrystals, which have a steep absorption onset, with absorption coefficients reaching >105 cm−1 just above its pseudo-direct bandgap of 1.4 eV. Surprisingly, we also observe an ultrafast (picosecond-time scale) photoconductivity decay and long-lived charge-carrier population persisting for over one microsecond in NaBiS2 nanocrystals. These unusual features arise because of the localised, non-bonding S p character of the upper valence band, which leads to a high density of electronic states at the band edges, ultrafast localisation of spatially-separated electrons and holes, as well as the slow decay of trapped holes. This work reveals the critical role of cation disorder in these systems on both absorption characteristics and charge-carrier kinetics.
Keywords: nanomaterials; crystals; thin films; bismuth; photoelectric cells
Contributing organizations
Related projects
- RADIATE - Research And Development with Ion Beams – Advancing Technology in Europe
- Sajavaara, Timo
- European Commission
Ministry reporting: Yes
Reporting Year: 2022
JUFO rating: 3