Polymer Donors Capable of Hydrogen-Bondings Enable Efficient and Stretchable Organic Solar Cells

Intrinsically stretchable organic solar cells (IS-OSCs) announced the new generation of wearable power sources. However, popular active materials are brittle, limiting its stretchability. Here, we develop highly efficient and durable IS-OSCs, by a new polymer donor (P_D­s, PM6- PhAmX (X=0, 3, 5, and 10)) capable of hydrogen-bonding (H-bonding). The incorporation of phenyl amide spacer (PhAm-FS) into the P_Ds increases the stretchability by enhanced molecular interaction from H-bonding. Consequently, the high power conversion efficiency (PCE, 17.5%) and crack onset strain (COS, 13.8%) were demonstrated in the PM6-PhAm5:Y7 blend, outclassing than PM6:Y7 blend (PCE = 15.5% and COS = 1.8%). More importantly, the IS-OSC based on the PM6-PhAm5:Y7 blend achieves the highest PCE (12.62%) among the reported IS-OSCs, and demonstrates outstanding stretchability.