The field of all-polymer solar cells (all-PSCs) has experienced rapid development during the past few years, mainly driven by the development of efficient polymer acceptors. However, the power conversion efficiencies (PCEs) of the all-PSCs are still limited by insufficient light absorption of the donor/acceptor blend and large energy loss in devices. We herein designed a polymer acceptor PYT1 constructed n-type molecular acceptor Y5-C20 as the key building block and blended it with a polymer donor PM6 to obtain an all-polymer photoactive layer. The optimized PM6:PYT1 all-PSCs achieved a record higher PCE of 13.43% with a very low energy loss of 0.47 eV and a photoresponse of up to 900 nm compared with the Y5-C20 based device with a best PCE of 9.42%. Furthermore, the PCEs of the PM6:PYT1 all-PSCs are relatively insensitive to the 1-chloronaphthalene (CN) additive contents and active layer thickness. Our results also highlight the effect of CN additive on PM6:PYT1 morphology, i.e., charge generation, and transport find an optimized balance, and radiative and non-radiative loss is simultaneously reduced in the blend. This work promotes the development of high-performance polymer acceptors and heralds a brighter future of all-PSCs for commercial applications.

在过去的几年中，全聚合物太阳能电池（all-PSC）领域经历了快速发展，这主要是由高效聚合物受体的发展所驱动。但是，全PSC的功率转换效率（PCE）仍然受到供体/受体混合物光吸收不足以及器件中的大量能量损失的限制。我们在本文中设计了一个以聚合物受体PYT1构造的n型分子受体Y5-C20作为关键构件，并将其与聚合物供体PM6共混以获得全聚合物光敏层。与基于Y5-C20的最佳PCE为9.42％的器件相比，经过优化的PM6：PYT1全PSC的PCE达到了创纪录的13.43％，具有非常低的能量损耗0.47 eV和高达900 nm的光响应。此外，PM6的PCE：PYT1全PSC对1-氯萘（CN）添加剂含量和活性层厚度相对不敏感。我们的结果还强调了CN添加剂对PM6：PYT1形态的影响，也就是说，电荷的产生和传输找到了最佳的平衡，并且混合物中的辐射损耗和非辐射损耗同时降低。这项工作促进了高性能聚合物受体的发展，并预示了全PSC在商业应用中的光明前景。