In continuation of the progressive development of cathode interfacial engineering for successfully improving the power conversion efficiency (PCE) of organic solar cells (OSCs), a breakthrough strategy of combining two small organic materials named Alq₃ (aluminum tris(8-hydroxyquinolinate)) and QPhPBr (tetraphenylphosphonium bromide) in one solution acting as a cathode interfacial layer (CIL) has been performed. The strong electron extracting property of Alq₃ determined previously and the crucial process of vacuum deposition led to our concept to propose this idea of a mixed binary solution processing technique. We successfully delivered a high performance of PCE above 11% with an increased V_oc (0.860 V), J_sc (18.38 mA cm⁻²) and FF (69.85%) using the combination of Alq₃ with QPhPBr as a CIL fabricated using a conventional device structure with PBDB-T:ITIC-Th as the blended active layer. The PCE is 2.5-fold higher than the reference device of bare Al cathode (4.38% PCE). Moreover, the binary mixed solution of CIL has shown a better performance than the Ca/Al based device with a PCE value 1.5 times higher than the value of 7.32% of the Ca/Al device. Their attractive performance has promoted a new challenge for new upcoming bulk-heterojunction OSCs in future prospects.

中文翻译：

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使用合理设计的电子提取层二元混合溶液改进的无富勒烯聚合物太阳能电池†

为了继续成功地发展阴极界面工程，以成功提高有机太阳能电池（OSC）的功率转换效率（PCE），结合了两种名为Alq _3的小型有机材料（三（8-羟基喹啉铝）铝和已经在一种溶液中执行了QPhPBr（溴化四苯基phosph）作为阴极界面层（CIL）的工作。先前确定的Alq ₃的强电子提取性能和真空沉积的关键过程导致我们提出了混合二元溶液处理技术这一思想。我们成功实现了11％以上的高性能PCE，并提高了V _oc（0.860 V），J _sc使用Alq ₃与QPhPBr的组合作为CIL （18.38 mA cm ^-2）和FF（69.85％）作为CIL，使用传统的器件结构以PBDB-T：ITIC-Th作为混合活性层来制造CIL。PCE比裸铝阴极（4.38％PCE）的参考器件高2.5倍。此外，CIL的二元混合溶液已显示出比基于Ca / Al的器件更好的性能，其PCE值比Ca / Al器件的7.32％的值高1.5倍。它们诱人的性能为未来的新型散装异质结OSC带来了新的挑战。