Ultrafast electron transfer reactions of ZnO solar cells sensitized with indoline dyes
Date | Do, 25.09.2014 | |
Time | 11.15 | |
Speaker | Dr. Egmont Rohwer, Institute of Applied Physics, University of Bern | |
Location | Universität Bern, Institut für Angewandte Physik, Gebäude exakte Wissenschaften, Hörsaal B116, Sidlerstrasse 5, 3012 Bern | |
Program | The initial charge transfer from dye molecules' excited states to the conduction band of a semiconductor, after absorption of visible light by the former, is critical to the performance of Dye sensitized Solar Cells (DSC). In a ZnO-based DSC sensitized by organic indoline dyes, the dynamics associated with charge transfer are investigated with femtosecond transient absorption spectroscopy. The time-resolved measurement of the photo-initiated processes reveal electron transfer rates corresponding to excited state lifetimes of 100s of fs, consistent with previously measured high absorbed photon to current conversion efficiencies and, on the molecular level, provide critical insight on the obstacles present in the pursuit of ever greater overall cell efficiency. | |
Link | www.iap.unibe.ch |