Selenium substitution for dielectric constant improvement and hole-transfer acceleration in non-fullerene organic solar cells

Xinjun He, Feng Qi, Xinhui Zou, Yanxun Li, Heng Liu, Xinhui Lu, Kam Sing Wong (), Alex K.-Y. Jen () and Wallace C. H. Choy ()
Additional contact information
Xinjun He: The University of Hong Kong
Feng Qi: City University of Hong Kong
Xinhui Zou: The Hong Kong University of Science and Technology
Yanxun Li: City University of Hong Kong
Heng Liu: Chinese University of Hong Kong
Xinhui Lu: Chinese University of Hong Kong
Kam Sing Wong: The Hong Kong University of Science and Technology
Alex K.-Y. Jen: City University of Hong Kong
Wallace C. H. Choy: The University of Hong Kong

Nature Communications, 2024, vol. 15, issue 1, 1-9

Abstract: Abstract Dielectric constant of non-fullerene acceptors plays a critical role in organic solar cells in terms of exciton dissociation and charge recombination. Current acceptors feature a dielectric constant of 3-4, correlating to relatively high recombination loss. We demonstrate that selenium substitution on acceptor central core can effectively modify molecule dielectric constant. The corresponding blend film presents faster hole-transfer of ~5 ps compared to the sulfur-based derivative (~10 ps). However, the blends with Se-acceptor also show faster charge recombination after 100 ps upon optical pumping, which is explained by the relatively disordered stacking of the Se-acceptor. Encouragingly, dispersing the Se-acceptor in an optimized organic solar cell system can interrupt the disordered aggregation while still retain high dielectric constant. With the improved dielectric constant and optimized fibril morphology, the ternary device exhibits an obvious reduction of non-radiative recombination to 0.221 eV and high efficiency of 19.0%. This work unveils heteroatom-substitution induced dielectric constant improvement, and the associated exciton dynamics and morphology manipulation, which finally contributes to better material/device design and improved device performance.

Date: 2024
References: View references in EconPapers View complete reference list from CitEc
Citations: View citations in EconPapers (1)

Downloads: (external link)
https://www.nature.com/articles/s41467-024-46352-2 Abstract (text/html)

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:nat:natcom:v:15:y:2024:i:1:d:10.1038_s41467-024-46352-2

Ordering information: This journal article can be ordered from
https://www.nature.com/ncomms/

DOI: 10.1038/s41467-024-46352-2

Access Statistics for this article

Nature Communications is currently edited by Nathalie Le Bot, Enda Bergin and Fiona Gillespie

More articles in Nature Communications from Nature
Bibliographic data for series maintained by Sonal Shukla () and Springer Nature Abstracting and Indexing ().