Highly efficient inverted polymer solar cells were demonstrated by incorporating a polyfluorene electrolyte to mitigate the intrinsic external defects of ITO cathode. The interfacial compatibility of solution-processed active layer and the cathode was improved using PFN/PFBT composite interlayer due to the optimized surface morphology and increased interfacial area. The hybrid PFN/PFBT electron transport layer suppressed recombination of the photo-excited carriers at the interface and facilitated subsequent charge transfer into the cathode. The leakage current as well as the series resistance of the device was decreased and the device reliability was improved. As a result, the electron collection efficiency from the active layer to the cathode was enhanced and the highest power conversion efficiency of 9.74% was achieved. The incorporated PFBT layer aimed to overcome the intrinsic defects of conventional transparent buffer layer based on the transition metal oxides, which make it spendable to fabricate the commercially viable photovoltaic devices.

通过掺入聚芴电解质以减轻ITO阴极的固有外部缺陷，证明了高效的倒置聚合物太阳能电池。使用PFN / PFBT复合中间层可改善溶液加工的活性层与阴极之间的界面相容性，这是由于优化了表面形态并增加了界面面积。混合PFN / PFBT电子传输层抑制了界面处光激发载流子的复合，并促进了随后的电荷转移到阴极。降低了器件的漏电流以及串联电阻，提高了器件的可靠性。结果，提高了从活性层到阴极的电子收集效率，并且获得了9.74％的最高功率转换效率。