Wang Jianxiao, Ma Xiaoling, Wang Jian, Ming Ruijie, An Qiaoshi, Zhang Jian, Yang Chuluo, Zhang Fujun
Key Laboratory of Luminescence and Optical Information, Ministry of Education, Beijing Jiaotong University, 100044, Beijing, P. R. China.
College of Physics and Electronic Engineering, Taishan University, 271021, Taian, Shandong Province, P. R. China.
Small. 2019 Oct;15(41):e1902602. doi: 10.1002/smll.201902602. Epub 2019 Aug 21.
Organic photovoltaics (OPVs) are fabricated with PM6 as donor and T6Me, IT-2F, or their mixture as acceptor. A 13.36% power conversion efficiency (PCE) is achieved from the optimized ternary OPVs with 50 wt% IT-2F in acceptors, which is attributed to the enhanced photon harvesting of ternary active layers and improved exciton utilization efficiency through energy transfer from IT-2F to T6Me. The efficient energy transfer from IT-2F to T6Me can be confirmed from the photoluminescence spectra of neat and blend films, which may provide additional channels to enhance exciton utilization efficiency for achieving short-circuit current density (J ) improvement of ternary OPVs. It should be highlighted that the fill factor (FF) of ternary OPVs can be monotonously increased along with the incorporation of IT-2F, indicating the gradually optimized phase separation degree of ternary active layers. The third component IT-2F plays a key role in optimizing phase separation as a morphology regulator. Over 8% PCE improvement is achieved in the optimized ternary OPVs compared with the over 12% PCEs of the corresponding binary OPVs, respectively. This work indicates that the performance of ternary OPVs can be well optimized by carefully picking materials with good compatibility and complementary absorption spectra, as well as the appropriate energy levels.
有机光伏电池（OPV）以PM6作为供体，T6Me、IT-2F或它们的混合物作为受体来制备。在受体中含有50 wt% IT-2F的优化三元OPV实现了13.36%的功率转换效率（PCE），这归因于三元活性层光子捕获的增强以及通过从IT-2F到T6Me的能量转移提高了激子利用效率。从纯膜和混合膜的光致发光光谱可以证实从IT-2F到T6Me的有效能量转移，这可能为提高激子利用效率提供额外的通道，以实现三元OPV短路电流密度（J）的提高。需要强调的是，三元OPV的填充因子（FF）会随着IT-2F的掺入而单调增加，这表明三元活性层的相分离程度逐渐优化。第三组分IT-2F作为形态调节剂在优化相分离中起关键作用。与相应二元OPV分别超过12%的PCE相比，优化后的三元OPV实现了超过8%的PCE提高。这项工作表明，通过仔细挑选具有良好兼容性和互补吸收光谱以及合适能级的材料，可以很好地优化三元OPV的性能。
