Influence of processing and intrinsic polymer parameters on photochemical stability of polythiophene thin films
- Authors:
-
-
Vesterager Madsen, Morten
;
Close
0000-0002-6838-9708
Department of Energy Conversion and Storage, Technical University of Denmark - Tromholt, Thomas ;
- Böttiger, Arvid P.L. ;
-
Andreasen, Jens Wenzel
;
Close0000-0002-3145-0229
Department of Energy Conversion and Storage, Technical University of Denmark -
Norrman, Kion
;
Close0000-0001-9355-7569
Department of Energy Conversion and Storage, Technical University of Denmark -
Krebs, Frederik C
Close0000-0003-1148-4314
Department of Energy Conversion and Storage, Technical University of Denmark
-
Vesterager Madsen, Morten
;
- DOI:
- 10.1016/j.polymdegradstab.2012.07.021
- Abstract:
- Intrinsic polymer parameters such as regio-regularity, molecular weight, and crystallinity play an important role when studying polymer stability. 18 different batches of poly-3-hexyl-thiophene (P3HT) were degraded in a solar simulator (AM1.5G, 1000 W/m2) and the degradation kinetics were monitored. The results suggest that the radical reaction responsible for the photodegradation takes place at terminal thiophene rings exposed at points were the conjugation is broken. This proposed mechanism is supported by the fact that stability scales with regio-regularity following the ratio of head-to-tail connected thiophene units. Annealing was found to relax the P3HT films and increase conjugation length and, in turn, increase stability observed as a delayed spectral blueshift caused by photochemical degradation. Crystallinity was found to play a minor role in terms of stability. Oxygen diffusion and light shielding effects were shown to have a negligible effect on the photochemical degradation rate. The results obtained in this work advance the understanding of polymer stability and will help improve the design of materials used for polymer solar cells resulting in longer lifetimes, which will push the technology closer to large-scale applications. © 2012 Elsevier Ltd. All rights reserved.
- Type:
- Journal article
- Language:
- English
- Published in:
- Polymer Degradation and Stability, 2012, Vol 97, Issue 11, p. 2412-2417
- Keywords:
- P3HT; Photooxidation; Organic photovoltaics; Photo-chemical stability; Degradation
- Main Research Area:
- Science/technology
- Publication Status:
- Published
- Review type:
- Peer Review
- Submission year:
- 2012
- Scientific Level:
- Scientific
- ID:
- 247774544
