High‐Performance Intrinsically‐Stretchable Organic Solar Cells Enabled by Electron Acceptors with Flexible Linkers

Abstract Intrinsically stretchable organic solar cells (IS‐OSCs) are emerging as promising candidates for powering next‐generation wearable electronics. However, developing molecular design strategies to achieve both high efficiency and mechanical robustness in IS‐OSCs remains a significant challenge. In this work, we present a novel approach by synthesizing a dimerized electron acceptor (DY‐FBrL) that enables rigid OSCs with a high power conversion efficiency (PCE) of 18.75 % and a crack‐onset strain (COS) of 18.54 %. The enhanced PCE and stretchability of DY‐FBrL‐based devices are attributed to its extended π‐conjugated backbone and elongated side chains. Furthermore, we introduce an innovative polymerized acceptor (PDY‐FL), synthesized via the polymerization of DY‐FBrL. While PDY‐FL‐based devices exhibit a slightly lower PCE of 14.13 %, they achieve a significantly higher COS of 23.45 %, representing one of the highest PCEs reported for polymerized acceptors containing only flexible linkers. Consequently, IS‐OSCs fabricated using DY‐FBrL and PDY‐FL achieve notable PCEs of 14.31 % and 11.61 %, respectively. Additionally, the device stretchability improves progressively from Y6 (strain at PCE 80% =11 %), to DY‐FBrL (strain at PCE 80% =23 %), and PDY‐FL (strain at PCE 80% =31 %). This study presents a promising molecular design strategy for tailoring electron acceptor structures, offering a new pathway to develop high‐performance IS‐OSCs with enhanced mechanical properties.