Charge transfer from an adsorbed ruthenium-based photosensitizer through an ultra-thin aluminium oxide layer and into a metallic substrate

Gibson, Andrew J.; Temperton, Robert H.; Handrup, Karsten; Weston, Matthew; Mayor, Louise Charlotte; O'Shea, James N.

Abstract

The interaction of the dye molecule N3 (cis-bis(isothiocyanato)bis(2,2-bipyridyl-4,4′-dicarbo-xylato)-ruthenium(II)) with the ultra-thin oxide layer on a AlNi(110) substrate, has been studied using synchrotron radiation based photoelectron spectroscopy, resonant photoemission spectroscopy, and near edge X-ray absorption fine structure spectroscopy. Calibrated X-ray absorption and valence band spectra of the monolayer and multilayer coverages reveal that charge transfer is possible from the molecule to the AlNi(110) substrate via tunnelling through the ultra-thin oxide layer and into the conduction band edge of the substrate. This charge transfer mechanism is possible from the LUMO+2 and 3 in the excited state but not from the LUMO, therefore enabling core-hole clock analysis, which gives an upper limit of 6.0 ± 2.5 fs for the transfer time. This indicates that ultra-thin oxide layers are a viable material for use in dye-sensitized solar cells, which may lead to reduced recombination effects and improved efficiencies of future devices.

Citation

Gibson, A. J., Temperton, R. H., Handrup, K., Weston, M., Mayor, L. C., & O'Shea, J. N. (2014). Charge transfer from an adsorbed ruthenium-based photosensitizer through an ultra-thin aluminium oxide layer and into a metallic substrate. Journal of Chemical Physics, 140(234708), Article 234708. https://doi.org/10.1063/1.4882867

• Journal Article Type: Article
• Publication Date: Jun 20, 2014
• Deposit Date: Feb 16, 2016
• Publicly Available Date: Feb 16, 2016
• Journal: Journal of Chemical Physics
• Print ISSN: 0021-9606
• Electronic ISSN: 1089-7690
• Publisher: American Institute of Physics
• Peer Reviewed: Peer Reviewed
• Volume: 140
• Issue: 234708
• Article Number: 234708
• DOI: https://doi.org/10.1063/1.4882867
• Keywords: charge transfer, surface photoemission, monolayers, multilayers, x-ray absorption
• Public URL: https://nottingham-repository.worktribe.com/output/730325
• Publisher URL: http://scitation.aip.org/content/aip/journal/jcp/140/23/10.1063/1.4882867
• Additional Information: Copyright 2014 AIP Publishing. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in The journal of chemical physics, v. 140 (234708) and may be found at http://scitation.aip.org/content/aip/journal/jcp/140/23/10.1063/1.4882867