标题：Ternary Organic Solar Cells with Efficiency >16.5% Based on Two Compatible Nonfullerene Acceptors
作者：Song, Jiali ;Li, Chao ;Zhu, Lei ;Guo, Jing ;Xu, Jinqiu ;Zhang, Xuning ;Weng, Kangkang ;Zhang, Kangning ;Min, Jie ;Hao, Xiaotao ;Zhang, Yuan ;Liu, Feng 更多 作者机构：[Song, Jiali ;Li, Chao ;Zhang, Xuning ;Weng, Kangkang ;Zhang, Yuan ;Sun, Yanming ] School of Chemistry, Beihang University, Beijing; 100191, China;[Gu 更多
摘要：A ternary structure has been demonstrated as being an effective strategy to realize high power conversion efficiency (PCE) in organic solar cells (OSCs); however, general materials selection rules still remain incompletely understood. In this work, two nonfullerene small-molecule acceptors 3TP3T-4F and 3TP3T-IC are synthesized and incorporated as a third component in PM6:Y6 binary blends. The photovoltaic behaviors in the resultant ternary OSCs differ significantly, despite the comparable energy levels. It is found that incorporation of 15% 3TP3T-4F into the PM6:Y6 blend results in facilitating exciton dissociation, increasing charge transport, and reducing trap-assisted recombination. All these features are responsible for the enlarged PCE of 16.7% (certified as 16.2%) in the PM6:Y6:3TP3T-4F ternary OSCs, higher than that (15.6%) in the 3TP3T-IC containing ternary devices. The performance differences are mainly ascribed to the compatibility between the third component and the host materials. The 3TP3T-4F guest acceptor exhibits an excellent compatibility with Y6, tending to form well-mixed phases in the ternary blend without disrupting the favored bicontinuous transport networks, whereas 3TP3T-IC displays a morphological incompatibility with Y6. This work highlights the importance of considering the compatibility for materials selection toward high-efficiency ternary organic OSCs.
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