We compare the performances of organic photovoltaic cells (OPVCs) based on binary and ternary planar heterojunctions. The organic active layers are pentathiophene (5T), subphthalocyanine (SubPc) and fullerene (C60). SubPc being an ambipolar material we used it either as electron acceptor in binary OPVCs or as central layer in ternary cells in order to increase the efficiency of OPVCs using 5T as electron donor. So, the different OPVC configurations were 5T/C60, 5T/SubPc and 5T/SubPc/C60. The effect of the different organic layer thicknesses on the device performances was studied. In order to understand the behavior of the different OPVC configurations, we proceeded with a morphological study. The influence of the high roughness of the 5T layer on the OPVCs performances is discussed. The best OPVCs performances are obtained with the binary structure 5T/SubPc. Its maximum efficiency corresponds to an increase of 50% compared to the OPVC based on the couple 5T/C60. External Quantum Efficiency measurements show that both layers participate to the current generation. The efficiency increase is mainly due to the increase of the open circuit voltage ([Formula: see text]). In the case of ternary OPVCs, [Formula: see text] is limited by the band structure of 5T and C60, moreover, the efficiency is also limited by the poor charge collection efficiency of the ternary structure and the series resistance of the three stacked organic layers.

中文翻译：

---

三元结构中以SubPc作为中心两极层和二元结构中作为电子受体的有机光伏电池性能比较

我们比较了基于二元和三元平面异质结的有机光伏电池 (OPVC) 的性能。有机活性层为五噻吩 (5T)、次酞菁 (SubPc) 和富勒烯 (C60）。SubPc 是一种双极性材料，我们将其用作二元 OPVC 中的电子受体或三元电池中的中心层，以提高使用 5T 作为电子供体的 OPVC 的效率。因此，不同的 OPVC 配置为 5T/C60, 5T/SubPc 和 5T/SubPc/C60. 研究了不同有机层厚度对器件性能的影响。为了了解不同 OPVC 配置的行为，我们进行了形态学研究。讨论了5T层的高粗糙度对OPVCs性能的影响。二元结构 5T/SubPc 获得了最佳的 OPVC 性能。与基于5T/C对的OPVC相比，其最大效率对应增加50%60. 外部量子效率测量表明，两层都参与了当前一代。效率的提高主要是由于开路电压的提高（[公式：见正文]）。在三元OPVCs的情况下，[公式：见正文]受限于5T和C的能带结构60，此外，效率还受到三元结构较差的电荷收集效率和三个堆叠有机层的串联电阻的限制。