Bracher, C., Yi, H., Scarratt, N.W. et al. (5 more authors) (2015) The effect of residual palladium catalyst on the performance and stability of PCDTBT:PC70BM organic solar cells. Organic Electronics, 27. pp. 266-273. ISSN 1566-1199
Abstract
Palladium (Pd) is commonly used as a catalyst in the polymerisation of conjugated polymers such as poly[N-9′-heptadecanyl-2,7-carbozole-alt-5,5-(4′,7′-di-2-thenyl-2′,1′,3′-benzothiadiazole)] (PCDTBT). Here we explore the effect of residual catalyst on the performance of organic photovoltaic devices (OPVs) based on a PCDTBT:fullerene thin-film blend. We find that as the relative concentration of Pd increases, the power conversion efficiency of the PV is reduced, dropping from 4.55% to 2.42% as the Pd concentration was increased to 2570 ppm (relative to that of the PCDTBT). This reduction in efficiency resulted primarily from a reduction in PV fill factor and shunt-resistance, indicating the presence of current-shunts within the device. Using optical microscopy, laser beam induced current mapping and scanning electron microscopy, we are able to demonstrate that such current shunts are associated with micron-sized aggregates of Pd-containing nanoparticles. We show that the presence of high concentrations of Pd within a PCDTBT OPV contribute to a larger drop in efficiency during the initial ‘burn-in’ period.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © 2015 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/) |
Keywords: | Organic photovoltaics; PCDTBT; Palladium; Lifetime; Stability |
Dates: |
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Institution: | The University of Sheffield |
Academic Units: | The University of Sheffield > Faculty of Engineering (Sheffield) > Department of Materials Science and Engineering (Sheffield) The University of Sheffield > Faculty of Science (Sheffield) > Department of Chemistry (Sheffield) The University of Sheffield > Faculty of Science (Sheffield) > Department of Physics and Astronomy (Sheffield) |
Funding Information: | Funder Grant number ENGINEERING AND PHYSICAL SCIENCE RESEARCH COUNCIL (EPSRC) EP/I028641/1 ENGINEERING AND PHYSICAL SCIENCE RESEARCH COUNCIL (EPSRC) EP/J017361/1 ENGINEERING AND PHYSICAL SCIENCE RESEARCH COUNCIL (EPSRC) EP/J017361/1 ENGINEERING AND PHYSICAL SCIENCE RESEARCH COUNCIL (EPSRC) EP/M014797/1 |
Depositing User: | Symplectic Sheffield |
Date Deposited: | 04 Mar 2016 12:52 |
Last Modified: | 04 Mar 2016 12:52 |
Published Version: | http://dx.doi.org/10.1016/j.orgel.2015.10.001 |
Status: | Published |
Publisher: | Elsevier |
Refereed: | Yes |
Identification Number: | 10.1016/j.orgel.2015.10.001 |
Related URLs: | |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:93351 |