Exploring the origin of high optical absorption in conjugated polymers
AuthorsVezie, Michelle S.
Ashraf, Raja Shahid
Goñi, Alejandro R.
Hayes, Sophia C.
KAUST DepartmentPhysical Sciences and Engineering (PSE) Division
Chemical Science Program
KAUST Solar Center (KSC)
MetadataShow full item record
AbstractThe specific optical absorption of an organic semiconductor is critical to the performance of organic optoelectronic devices. For example, higher light-harvesting efficiency can lead to higher photocurrent in solar cells that are limited by sub-optimal electrical transport. Here, we compare over 40 conjugated polymers, and find that many different chemical structures share an apparent maximum in their extinction coefficients. However, a diketopyrrolopyrrole-thienothiophene copolymer shows remarkably high optical absorption at relatively low photon energies. By investigating its backbone structure and conformation with measurements and quantum chemical calculations, we find that the high optical absorption can be explained by the high persistence length of the polymer. Accordingly, we demonstrate high absorption in other polymers with high theoretical persistence length. Visible light harvesting may be enhanced in other conjugated polymers through judicious design of the structure.
CitationVezie MS, Few S, Meager I, Pieridou G, Dörling B, et al. (2016) Exploring the origin of high optical absorption in conjugated polymers. Nature Materials 15: 746–753. Available: http://dx.doi.org/10.1038/nmat4645.
SponsorsM.S.V. and S.F. are grateful to the Engineering and Physical Sciences Research Council (EPSRC) for a doctoral training award and a CDT studentship (EP/G037515/1), respectively. G.P. and S.C.H. acknowledge the University of Cyprus for funding through the internal grant 'ORGANIC'. B.D., A.R.G. and M.C.-Q. acknowledge financial support from the Ministerio de Economia y Competitividad of Spain through projects CSD2010-00044 (Consolider NANOTHERM), SEV-2015-0496 and MAT2012-37776 and the European Research Council through project ERC CoG648901. I.Meager., R.S.A. and I.McCulloch acknowledge support from the European Commission FP7 Project ArtESun (604397). J.N. is grateful to the Royal Society for a Wolfson Merit Award, and acknowledges financial support from EPSRC grants EP/K030671/1, EP/K029843/1 and EP/J017361/1. The authors thank I. Alonso for performing supplementary ellipsometric measurements; we thank T. Kirchartz, J. Moore Frost, C. Muller, I. Alonso and A. Myers for helpful discussions.
- Diketopyrrolopyrrole Polymers for Organic Solar Cells.
- Authors: Li W, Hendriks KH, Wienk MM, Janssen RA
- Issue date: 2016 Jan 19
- Enhancing the photocurrent in diketopyrrolopyrrole-based polymer solar cells via energy level control.
- Authors: Li W, Roelofs WS, Wienk MM, Janssen RA
- Issue date: 2012 Aug 22
- Rational design of D-A1-D-A2 conjugated polymers with superior spectral coverage.
- Authors: Hedström S, Tao Q, Wang E, Persson P
- Issue date: 2015 Oct 28
- Approaching disorder-free transport in high-mobility conjugated polymers.
- Authors: Venkateshvaran D, Nikolka M, Sadhanala A, Lemaur V, Zelazny M, Kepa M, Hurhangee M, Kronemeijer AJ, Pecunia V, Nasrallah I, Romanov I, Broch K, McCulloch I, Emin D, Olivier Y, Cornil J, Beljonne D, Sirringhaus H
- Issue date: 2014 Nov 20
- Optoelectronic and charge transport properties at organic-organic semiconductor interfaces: comparison between polyfluorene-based polymer blend and copolymer.
- Authors: Kim JS, Lu L, Sreearunothai P, Seeley A, Yim KH, Petrozza A, Murphy CE, Beljonne D, Cornil J, Friend RH
- Issue date: 2008 Oct 1