Organic solar cells (OSCs) have attracted research interest by their elastic character for wearable and stretchable devices. Especially all-polymer OSCs with same composition unit between donor and acceptor are enhanced their thermal stability and mechanical robustness. However, in most of OSCs, high elasticity often reduces the power conversion efficiency (PCE) by low charge transfer be cacused by weak aggregation of each donor and acceptor composite. In this study, new polymer acceptors consisted by the poly siloxane-spacer (PSS) with benzoditohiophene (BDT) and Y6 non-fullerene small molecule acceptor (NFSMA) derivative are synthesized and characterized for high performance and highly stretchable OSCs. The PSS unit has intrinsically stretchable property due to their rubber like structure, therefore introducing PSS unit as a building block in the OSC polymers suggests improve its own elasticity of the OSC polymers. In addition, introducing PSS unit increase solubility of OSC polymers, enabling high performance OSC by solution process using a non-halogenated green solvents. For example, all-polymer OSCs based on PSS containing polymer achieved more high PCE value (13.5 %) and crock-onset strain (COS = 15.2 %) than non-containing one (PCE = 9.8% and COS = 9.6%)
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