POS5-0841
Molecularly Controlled Thermoplastic Elastomers for Highly Efficient and Stretchable Organic Solar Cells
Topic
S5. Polymers for Electronics and Photonics
When and Where
Sep 29, 2026
08:30 - 09:30
Room 301 (Grand Ballroom)
Session Chairs
Hae Jung SON
Boseok KANG
Presenter(s)
Jongmin Oh (KAIST)
Co-Author(s)
Abstract
High power conversion efficiency (PCE) and mechanical stretchability are key requirements for wearable applications of organic solar cells (OSCs). While incorporating elastomers into photoactive layer can effectively enhance mechanical compliance, excessive dilution of electrical pathways significantly compromises photovoltaic performance. To address this issue, we explored the effect of hard block composition on the photovoltaic performance utilizing representative block copolymer elastomer, styrene-ethylene-butylene-styrene (SEBS). We blended 50wt% of SEBS into bottom donor layer of planar heterojunction-type photoactive layer. We systematically varied SEBS with polystyrene (PS) fractions - low, intermediate, and high - to investigate how block composition influences the photovoltaic performance and film morphology. Among the tested systems, the intermediate PS fraction SEBS yielded the highest PCE, whereas the others showed insufficient PCE. This achievement is attributed to a preferential face-on orientation of conjugated polymer donor crystallites. Additionally, the confinement of donor fibrils by the hard PS domains further facilitates efficient charge transport. These results emphasize that the optimized block composition of elastomer is essential for maximizing charge transport in stretchable photoactive layers. This research provides a rational design approach for high-performance OSCs suitable for wearable applications.
