Alqurashi, R., Griffin, J., Alsulami, A. et al. (1 more author) (2016) Open-Circuit Voltage in Inverted Polycarbazole:Fullerene Bulk Heterojunction Solar Cells. IEEE Journal of Photovoltaics, 6 (4). pp. 918-923. ISSN 2156-3381
Abstract
The correlation between cathode work function and open-circuit voltages (Voc) in inverted polycarbazole:fullerene (PCDTBT:PC70BM) bulk-heterojunction solar cells has been investigated by postannealing of indium tin oxide (ITO) electrodes. The ITO function is seen to change from 4.2 to 4.5 eV without the need to insert additional interfacial layers with annealing temperature up to 400 °C. The best device performance was obtained at room temperature with the ITO work function of 4.2 eV with a Voc of 0.89 eV, a Jsc of 8.06 mA·cm-2, a fill factor (FF) of 64.70%, and a power conversion efficiency of 4.62%. Together with previously published results, we are able to extract two regimes of Voc dependence on the cathode work function: first, a linear relationship when the cathode work function exceeds the lowest unoccupied molecular orbital (LUMO) of PCBM and, second, a constant Voc regime when the ITO work function reduces below the LUMO level. These results provide general guidelines for the cathode contact design in inverted polymer solar cells.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © 2016 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this material for advertising or promotional purposes, creating new collective works for resale or redistribution to servers or lists, or reuse of any copyrighted components of this work in other works. Reproduced in accordance with the publisher's self-archiving policy. |
Keywords: | Indium tin oxide; Annealing, Resistance; Photovoltaic cells; Temperature measurement; Cathodes, work function (WF;, Bulk heterojunction; cathode modification; Fermi level pinning; open-circuit voltage; photoelectron spectroscopy; polycarbazole; thermal annealing |
Dates: |
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Institution: | The University of Sheffield |
Academic Units: | The University of Sheffield > Faculty of Science (Sheffield) > Department of Physics and Astronomy (Sheffield) |
Depositing User: | Symplectic Sheffield |
Date Deposited: | 01 Sep 2016 13:22 |
Last Modified: | 03 Nov 2016 04:28 |
Published Version: | https://dx.doi.org/10.1109/JPHOTOV.2016.2553850 |
Status: | Published |
Publisher: | IEEE |
Refereed: | Yes |
Identification Number: | 10.1109/JPHOTOV.2016.2553850 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:104230 |