Growing interests have been devoted to the synthesis of polymer acceptors as alternatives to fullerene derivatives to realize high-performance and stable all-polymer solar cells (all-PSCs). So far, one of the key factors that limit the performance of all-PSCs is low photocurrent density (normally < 14 mA/cm²). One potential solution is to improve the dielectric constants (ε_r) of polyme_r:polymer blends, which tend to reduce the binding energy of excitons, thus boosting the exciton dissociation efficiencies. Nevertheless, the correlation between ε_r and photovoltaic performance has been rarely investigated for all-PSCs. In this work, five fluorinated naphthalene diimide (NDI)-based acceptor polymers, with different content of fluorine were synthesized. The incorporation of fluorine increased the ε_r of the acceptor polymers and blend films, which improved the charge generation and overall photocurrent of the all-PSCs. As a result, the PTB7-Th:PNDI-FT10 all-PSC attained a high power conversion efficiency (PCE) of 7.3% with a photocurrent density of 14.7 mA/cm², which surpassed the values reported for the all-PSC based on the non-fluorinated acceptor PNDI-T10. Interestingly, similarly high photovoltaic performance was maintained regardless of a large variation of donor:acceptor ratios, which revealed the good morphological tolerance and the potential for robust production capability of all-PSCs.

为了实现高性能和稳定的全聚合物太阳能电池（all-PSC），人们越来越关注合成聚合物受体以替代富勒烯衍生物。到目前为止，限制全PSC性能的关键因素之一是光电流密度低（通常<14 mA / cm ²）。一个可能的解决方案是提高介电常数（ε _ř聚合物：）_{- [R} ：聚合物共混物，其倾向于降低激子的结合能，从而带动激子解离效率。然而，之间的相关性ε _{- [R}几乎没有研究过全PSC的光伏性能。在这项工作中，合成了五种具有不同氟含量的氟化萘二酰亚胺（NDI）基受体聚合物。氟的引入增加了ε _{- [R}受体的聚合物和共混物薄膜，这改善了电荷产生和全的PSC的总体光电流。结果，PTB7-Th：PNDI-FT10全PSC在光电流密度为14.7 mA / cm ^{2的情况下}获得了7.3％的高功率转换效率（PCE）。，超过了基于非氟化受体PNDI-T10报告的全PSC值。有趣的是，无论施主与受主的比率变化如何，都可以保持相似的高光伏性能，这显示出良好的形态学耐受性和潜在的全PCC生产能力。