In this work a novel combination of side chain functionalities, alkyl-phosphonate (EP) and alkyl-ammonium bromide (NBr) groups, on a polyfluorene backbone (PF-NBr-EP) was studied as cathode interfacial material (CIM) in polymer-based solar cells. The devices were made with a conventional geometry, with PTB7:PC₇₁ BM as active layer and aluminum as metal electrode. The CIM showed good solubility in ethanol and film forming ability onto the active layer so that its deposition could be finely tuned. The interface engineering imparted by this CIM was assessed and discussed through kelvin probe force microscopy (KPFM), impedance spectroscopy, charge recombination and electron transport characterizations. To discriminate between the interfacial modifications imparted by the interlayer and its solvent, we included in this study a surface ethanol treated device. In the optimized conditions an average power conversion efficiency of 7.24% was obtained, which is about 60% higher when compared to devices made with bare Al and 26% when compared to devices made with a standard calcium/aluminum cathode. Besides performances, some insights about the devices shelf life stability are also presented. A good persistency through aging was found for the cathode interfacial engineering capabilities of PF-NBr-EP.

在这项工作中，研究了在聚芴骨架（PF-NBr-EP）上的侧链官能团，烷基膦酸酯（EP）和烷基溴化铵（NBr）基团的新型组合，作为聚合物中的阴极界面材料（CIM）。太阳能电池。器件采用常规几何形状制造，并带有PTB7：PC ₇₁BM为活性层，铝为金属电极。CIM在乙醇中显示出良好的溶解性，并且在活性层上具有成膜能力，因此可以对其沉积进行微调。通过开尔文探针力显微镜（KPFM），阻抗谱，电荷重组和电子传输表征，评估和讨论了该CIM赋予的界面工程。为了区分中间层和其溶剂赋予的界面改性，我们在本研究中包括了表面乙醇处理过的设备。在优化的条件下，平均功率转换效率为7.24％，与使用裸铝制成的器件相比约高60％，与使用标准钙/铝阴极制成的器件相比约高26％。除了表演 还介绍了有关设备保质期稳定性的一些见解。对于PF-NBr-EP的阴极界面工程能力，发现了通过老化具有良好的持久性。