Affiliation:
1. Department of Chemical and Biomolecular Engineering Korea Advanced Institute of Science and Technology (KAIST) Daejeon 34141 Republic of Korea
2. Department of Materials Engineering and Convergence Technology and ERI Gyeongsang National University Jinju 52828 Republic of Korea
3. Department of Mechanical Engineering Korea Advanced Institute of Science and Technology (KAIST) Daejeon 34141 Republic of Korea
4. Department of Chemistry and RIGET Gyeongsang National University Jinju 52828 Republic of Korea
Abstract
AbstractAll‐polymer solar cells (all‐PSCs), using polymerized non‐fullerene acceptors (PNFAs), have shown promise in improving device stabilities compared to small‐molecular acceptor‐based PSCs. However, low mixing entropy between polymer donors (PDs) and PNFAs hampers the development of optimized blend morphology. Herein, this study develops efficient conjugated polymers that serve as interfacial compatibilizers between host PD and PNFA. Ternary all‐polymer blends containing the compatibilizer demonstrate improved blend morphology with strengthened interfaces, resulting in better photovoltaic properties and thermal/mechanical stabilities. In detail, the power conversion efficiency (PCE) increases from 15.4 to 17.1% upon the addition of the compatibilizer. Moreover, the devices based on the ternary blend enable good thermal stability, retaining 90% of the initial PCE after 96 h at 125 °C. Additionally, the mechanical properties are improved; the cohesive fracture energy (Gc) of 2.6 J m−2 and crack onset strain (COS) of 20.4% of the ternary blend outperform those of the binary blend (Gc = 1.1 J m−2 and COS = 16.5%). Resultingly, the stretchable PSCs based on the ternary blend exhibit an excellent PCE of 13.7% and stretchability with a strain at PCE80% of 35%.
Funder
National Research Foundation of Korea
Subject
General Materials Science,Renewable Energy, Sustainability and the Environment