Orientation control of regioregular-poly(3-dodecylthiophene) films formed by the friction-transfer method and the performance of organic photovoltaic devices based on these films
Article first published online: 14 NOV 2013
Copyright © 2013 Wiley Periodicals, Inc.
Journal of Applied Polymer Science
Volume 131, Issue 8, April 15, 2014
How to Cite
2014). Orientation control of regioregular-poly(3-dodecylthiophene) films formed by the friction-transfer method and the performance of organic photovoltaic devices based on these films. J. Appl. Polym. Sci. 131, 40136, doi: 10.1002/app.40136, , , and (
- Issue published online: 27 JAN 2014
- Article first published online: 14 NOV 2013
- Manuscript Accepted: 29 OCT 2013
- Manuscript Received: 2 AUG 2013
- friction transfer;
- organic photovoltaic devices;
- conducting polymers
Control of the molecular orientation of regioregular poly(3-alkylthiophene)s (RR-P3ATs) improves the performance of field-effect transistors and organic photovoltaic devices (OPVs). However, most thiophene ring planes of the RR-P3AT molecules (except RR-poly(3-butylthiophene)) in films formed by the conventional spin-coating method stand on the substrate, that is, edge-on orientation. Orientation control of RR-poly(3-dodecylthiophene) (RR-P3DDT) molecules in films formed by the friction transfer method is reported and the performance of OPVs based on friction-transferred RR-P3DDT films is compared to that of OPVs based on spin-coated films. The films are investigated by polarized ultraviolet–visible light absorption spectroscopy, Fourier transform infrared spectroscopy, and grazing-incidence X-ray diffraction measurement. For friction-transferred films, the RR-P3DDT molecular chain is uniaxially aligned parallel to the substrate plane. In addition, the thiophene ring planes of the RR-P3DDT molecules are also oriented parallel to the substrate plane, that is, face-on orientation. The power conversion efficiency (PCE) and fill factor of the RR-P3DDT/C60 bilayer OPVs based on the friction-transferred RR-P3DDT films are higher than those of devices based on spin-coated films. The PCE and photocurrent of the device based on the friction-transferred film are larger under irradiation with polarized light parallel to the RR-P3DDT molecular chain direction than with polarized light orthogonal to the chain direction. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40136.