1099-0518/asset/olbannerleft.gif?v=1&s=fc20dbd19f6b9e174aeaebd5b857bc6a2086bac1)
1099-0518/asset/olbannerright.gif?v=1&s=868808a544e30480468a320e0fa53c0c810010ad)
Article
Novel narrow-band-gap conjugated copolymers containing phenothiazine-arylcyanovinyl units for organic photovoltaic cell applications
Article first published online: 23 MAY 2008
DOI: 10.1002/pola.22715
Copyright © 2008 Wiley Periodicals, Inc.
Issue
Journal of Polymer Science Part A: Polymer Chemistry
Volume 46, Issue 13, pages 4285–4304, 1 July 2008
Additional Information
How to Cite
Li, K.-C., Hsu, Y.-C., Lin, J.-T., Yang, C.-C., Wei, K.-H. and Lin, H.-C. (2008), Novel narrow-band-gap conjugated copolymers containing phenothiazine-arylcyanovinyl units for organic photovoltaic cell applications. Journal of Polymer Science Part A: Polymer Chemistry, 46: 4285–4304. doi: 10.1002/pola.22715
Publication History
- Issue published online: 27 MAY 2008
- Article first published online: 23 MAY 2008
- Manuscript Accepted: 23 FEB 2008
- Manuscript Received: 16 JAN 2008
Funded by
- National Science Council of Taiwan (ROC). Grant Number: NSC 94-2113M-009-011
- Chung-Shan Institute of Science and Technology (in Taiwan)
- Abstract
- Article
- References
- Cited By
Keywords:
- conjugated polymers;
- copolymerization;
- heteroatom-containing polymers;
- narrow band gap polymers;
- phenothiazine derivatives;
- photovoltaic cells
Graphical Abstract
Novel narrow-band-gap copolymers consisting of the comonomers alkyl-substituted fluorene and mono- and bis(2-aryl-2-cyanovinyl)-10-hexylphenothiazine were copolymerized by a padallium-catalyzed Suzuki coupling reaction in 61–89% yields with two different feed ratios. The polymers showed broad optical absorption from 400 to 800 nm with optical band gaps at 1.55–2.10 eV. Polymer solar cells were fabricated using [6,6]-phenyl C61 butyric acid methyl ester (PCBM) as an electron acceptor, and the device of copolymer P12 produced the highest preliminary result having an open-circuit voltage of 0.64 V, a short-circuit current of 2.70 mA/cm2, a fill factor of 0.29, and an energy conversion efficiency of 0.51%.
Abstract
A series of novel narrow-band-gap copolymers (P1-P12) composed of alkyl-substituted fluorene (FO) units and six analogous mono- and bis(2-aryl-2-cyanovinyl)-10-hexylphenothiazine monomers (M1-M6) were synthesized by a palladium-catalyzed Suzuki coupling reaction with two different feed in ratios of FO to M1-M6 (molar ratio = 3:1 and 1:1). The absorption spectra of polymers P1-P12 exhibited broad peaks located in the UV and visible regions from 400 to 800 nm with optical band gaps at 1.55–2.10 eV, which fit near the wavelength of the maximum solar photon reflux. Electrochemical experiments displayed that the reversible p- and n-doping processes of copolymers were partially reversible, and the proper HOMO/LUMO levels enabled a high photovoltaic open-circuit voltage. As blended with [6,6]-phenyl C61 butyric acid methyl ester (PCBM) as an electron acceptor in bulk heterojunction photovoltaic devices, narrow-band-gap polymers P1-P12 as electron donors showed significant photovoltaic performance which varied with the intramolecular donor-acceptor interaction and their mixing ratios to PCBM. Under 100 mW/cm2 of AM 1.5 white-light illumination, the device of copolymer P12 produced the highest preliminary result having an open-circuit voltage of 0.64 V, a short-circuit current of 2.70 mA/cm2, a fill factor of 0.29, and an energy conversion efficiency of 0.51%. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 4285–4304, 2008