Hong Ling, Yao Huifeng, Yu Runnan, Xu Ye, Gao Bowei, Ge Ziyi, Hou Jianhui
Ningbo Institute of Materials Technology and Engineering , Chinese Academy of Sciences , Ningbo 315201 , P. R. China.
University of Chinese Academy of Sciences , Beijing 100049 , P. R. China.
ACS Appl Mater Interfaces. 2019 Aug 14;11(32):29124-29131. doi: 10.1021/acsami.9b10243. Epub 2019 Aug 5.
The large energy loss () in organic solar cells (OSCs) relative to those of silicon or inorganic/organic hybrid perovskite solar cells is one of the major factors limiting the power conversion efficiency (PCE) of OSCs. Recently, OSCs based on nonfullerene acceptors (NFAs) have achieved high PCEs at decreased values. Therefore, the present study investigates the relationship between and the device performance of NFA-based OSCs. Here, we select two polymer donors (PBDB-T and its fluorinated derivative PBDB-TF) and blend each polymer donor with each of three NFAs (indaceno[1,2-:5,6-']dithiophene and 2-(3-oxo-2,3-dihydroinden-1-ylidene)malononitrile (IEIC) and its respective fluorinated and chlorinated derivatives IE-4F and IE-4Cl), which provide varied energy-level alignments. The six blends exhibit similar morphologies and charge transport properties but varied values in OSCs. The results indicate that the charge generation and PCE of the OSCs increase with the increasing . Accordingly, the PBDB-T:IE-4Cl-based device yields the highest PCE of 11.1% with an of 0.64 eV, while the PBDB-TF:IEIC-based device provides a significantly decreased PCE of 3.8% with a diminished of 0.52 eV. These results demonstrate the great importance of finely tuning the energy-level alignments of these types of donor/acceptor systems to achieve the best device performance.
与硅或无机/有机混合钙钛矿太阳能电池相比，有机太阳能电池（OSCs）存在较大的能量损失（），这是限制OSCs功率转换效率（PCE）的主要因素之一。最近，基于非富勒烯受体（NFAs）的OSCs在降低的值时实现了高PCE。因此，本研究调查了与基于NFA的OSCs器件性能之间的关系。在这里，我们选择了两种聚合物供体（PBDB-T及其氟化衍生物PBDB-TF），并将每种聚合物供体与三种NFA（茚并[1,2-:5,6-']二噻吩和2-(3-氧代-2,3-二氢茚-1-亚基)丙二腈（IEIC）及其各自的氟化和氯化衍生物IE-4F和IE-4Cl）中的每一种混合，这些NFA提供了不同的能级排列。这六种混合物在OSCs中表现出相似的形态和电荷传输特性，但值不同。结果表明，OSCs的电荷产生和PCE随着的增加而增加。因此，基于PBDB-T:IE-4Cl的器件产生了11.1%的最高PCE，为0.64 eV，而基于PBDB-TF:IEIC的器件PCE显著降低，为3.8%，降低至0.52 eV。这些结果证明了精细调节这类供体/受体系统的能级排列对于实现最佳器件性能的重要性。
