High-Performance Intrinsically Stretchable Polymer Solar Cell with Record Efficiency and Stretchability Enabled by Thymine-Functionalized Terpolymer

• Published in: Journal of the American Chemical Society Vol. 145; no. 22; pp. 11914 - 11920
• Main Authors: Wan, Qingpei, Seo, Soodeok, Lee, Sun-Woo, Lee, Jinho, Jeon, Hyesu, Kim, Taek-Soo, Kim, Bumjoon J., Thompson, Barry C.
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 07.06.2023
• ISSN: 0002-7863; 1520-5126
• DOI: 10.1021/jacs.3c02764

Designing new polymer semiconductors for intrinsically stretchable polymer solar cells (IS-PSCs) with high power conversion efficiency (PCE) and durability is critical for wearable electronics applications. Nearly all high-performance PSCs are constructed using fully conjugated polymer donors (P D) and small-molecule acceptors (SMA). However, a successful molecular design of P Ds for high-performance and mechanically durable IS-PSCs without sacrificing conjugation has not been realized. In this study, we design a novel thymine side chain terminated 6,7-difluoro-quinoxaline (Q-Thy) monomer and synthesize a series of fully conjugated P Ds (PM7-Thy5, PM7-Thy10, PM7-Thy20) featuring Q-Thy. The Q-Thy units capable of inducing dimerizable hydrogen bonding enable strong intermolecular P D assembly and highly efficient and mechanically robust PSCs. The PM7-Thy10:SMA blend demonstrates a combination of high PCE (>17%) in rigid devices and excellent stretchability (crack-onset value >13.5%). More importantly, PM7-Thy10-based IS-PSCs show an unprecedented combination of PCE (13.7%) and ultrahigh mechanical durability (maintaining 80% of initial PCE after 43% strain), illustrating the promising potential for commercialization in wearable applications.