Two polymer donors, FTAZ and J71 , and two fused-ring electron acceptors, ITIC1 and ITIC2 , are used to investigate the effects of conjugation dimension on the performance of organic solar cells (OSCs). FTAZ and J71 , and ITIC1 and ITIC2 share the same molecular backbone, respectively, while J71 and ITIC2 possess conjugated thienyl side chains. The addition of conjugated side chains slightly red-shifts the absorption spectra and lowers the bandgap due to the extended 2D conjugation. Conjugated side chains on the acceptor induce the self-aggregation of the acceptors, while conjugated side chains on the donor increase the miscibility of the donors and acceptors, thus optimizing the morphology of the active layers. The blends based on mixed combinations, namely 1D donor/2D acceptor and 2D donor/1D acceptor, show better performance relative to 1D donor/1D acceptor and 2D donor/2D acceptor.
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Alkyl Chain Length Effects of Polymer Donors on the Morphology and Device Performance of Polymer Solar Cells with Different Acceptors
The development of nonfullerene acceptors has brought polymer solar cells into a new era. Maximizing the performance of nonfullerene solar cells needs appropriate polymer donors that match with the acceptors in both electrical and morphological properties. So far, the design rationales for polymer donors are mainly borrowed from fullerene‐based solar cells, which are not necessarily applicable to nonfullerene solar cells. In this work, the influence of side chain length of polymer donors based on a set of random terpolymers PTAZ‐TPD10‐C
- Award ID(s):
- 1757220
- NSF-PAR ID:
- 10460511
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Energy Materials
- Volume:
- 9
- Issue:
- 30
- ISSN:
- 1614-6832
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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