Significant efficiency enhancements in non‐Y series acceptors by the addition of outer side chains
Author(s)
Type
Journal Article
Abstract
Most current highly efficient organic solar cells utilize small molecules like Y6 and its derivatives as electron acceptors in the photoactive layer. In this work, a small molecule acceptor, SC8-IT4F, is developed through outer side chain engineering on the terminal thiophene of a conjugated 6,12-dihydro-dithienoindeno[2,3-d:2′,3′-d′]-s-indaceno[1,2-b:5,6-b′]dithiophene (IDTT) central core. Compared to the reference molecule C8-IT4F, which lacks outer side chains, SC8-IT4F displays notable differences in molecule geometry (as shown by simulations), thermal behavior, single-crystal packing, and film morphology. Blend films of SC8-IT4F and the polymer donor PM6 exhibit larger carrier mobilities, longer carrier lifetimes, and reduced recombination compared to C8-IT4F, resulting in improved device performance. Binary photovoltaic devices based on the PM6:SC8-IT4F films reveal an optimal efficiency over 15%, which is one of the best values for non-Y type small molecule acceptors (SMAs). The resultant devices also show better thermal and operational stability than the control PM6:L8-BO devices. SC8-IT4F and its blend exhibit a higher relative degree of crystallinity and π coherence length, compared to C8-IT4F samples, beneficial for charge transport and device performance. The results indicate that outer side chain engineering on existing small electron acceptors can be a promising molecular design strategy for further pursuing high-performance organic solar cells.
Date Issued
2025-03-20
Date Acceptance
2025-01-01
Citation
Advanced Science, 2025, 12 (11)
ISSN
2198-3844
Publisher
Wiley
Journal / Book Title
Advanced Science
Volume
12
Issue
11
Copyright Statement
© 2025 The Author(s). Advanced Science published by Wiley-VCH GmbH This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
License URL
Identifier
https://www.ncbi.nlm.nih.gov/pubmed/39840615
Subjects
IDTT
organic solar cell
side chain engineering
small molecule acceptor
steric hindrance
Publication Status
Published
Coverage Spatial
Germany
Article Number
2414042
Date Publish Online
2025-01-22