| 초록 |
Developing polymer solar cells (PSCs) with high photovoltaic performance and mechanical robustness is one of the most urgent tasks to ensure their operational reliability and applicability in wearable devices. Here, we develop a series of novel polymer donors (PDs), with which highly efficient PSCs with remarkable mechanical reliability are demonstrated. By interposing controlled amount of 1,10-di(thiophen-2-yl)decane flexible spacer (FS) into a PM6 backbone, we are able to significantly enhance the intermixing of the new PDs with small molecule acceptor (Y7), affording sufficient pathways for efficient charge percolation and mechanical stress dissipation. As a result, PSCs based on the PD containing 5 mol% FS unit and Y7 exhibit a high power conversion efficiency (PCE) of 17% with a crack onset strain (COS) of 12% and a cohesive fracture energy (Gc) of 2.1 J m–2, significantly outperforming the reference PM6-based devices (PCE = 15%, COS = 2% and Gc= 1.0 J m–2). |
