Zhan Lingling, Li Shuixing, Zhang Huotian, Gao Feng, Lau Tsz-Ki, Lu Xinhui, Sun Danyang, Wang Peng, Shi Minmin, Li Chang-Zhi, Chen Hongzheng
State Key Laboratory of Silicon Materials MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027 P. R. China.
Biomolecular and Organic Electronics IFM Linköping University Linköping 58183 Sweden.
Adv Sci (Weinh). 2018 Jun 20;5(8):1800755. doi: 10.1002/advs.201800755. eCollection 2018 Aug.
Herein, efficient organic solar cells (OSCs) are realized with the ternary blend of a medium band gap donor (poly[(2,6-(4,8-bis(5-(2-ethylhexyl)thiophen-2-yl)-benzo[1,2-b:4,5-b']dithiophene))-alt-(5,5-(1',3'-di-2-thienyl-5',7'-bis(2-ethylhexyl)benzo[1',2'-c:4',5'-c']dithiophene-4,8-dione)] (PBDB-T)) with a low band gap acceptor (2,2'-((2Z,2'Z)-(((2,5-difluoro-1,4-phenylene)bis(4,4-bis(2-ethylhexyl)-4H-cyclopenta[2,1-b:3,4-b']dithiophene-6,2-diyl))bis(methanylylidene))bis(5,6-difluoro-3-oxo-2,3-dihydro-1H-indene-2,1-diylidene))dimalononitrile (HF-PCIC)) and a near-infrared acceptor (2,2'-((2Z,2'Z)-(((4,4,9,9-tetrakis(4-hexylphenyl)-4,9-dihydro-s-indaceno[1,2-b:5,6-b']dithiophene-2,7-diyl)bis(4-((2-ethylhexyl)oxy)thiophene-5,2-diyl))bis(methanylylidene))bis(5,6-difluoro-3-oxo-2,3-dihydro-1H-indene-2,1-diylidene))dimalononitrile (IEICO-4F)). It is shown that the introduction of IEICO-4F third component into PBDB-T:HF-PCIC blend increases the short-circuit current density () of the ternary OSC to 23.46 mA cm, with a 44% increment over those of binary devices. The significant current improvement originates from the broadened absorption range and the active layer morphology optimization through the introduction of IEICO-4F component. Furthermore, the energy loss of the ternary cells (0.59 eV) is much decreased over that of the binary cells (0.80 eV) due to the reduction of both radiative recombination from the absorption below the band gap and nonradiative recombination upon the addition of IEICO-4F. Therefore, the power conversion efficiency increases dramatically from 8.82% for the binary cells to 11.20% for the ternary cells. This work provides good examples for simultaneously achieving both significant current enhancement and energy loss mitigation in OSCs, which would lead to the further construction of highly efficient ternary OSCs.
在此，通过中带隙供体（聚[(2,6-(4,8-双(5-(2-乙基己基)噻吩-2-基)-苯并[1,2-b:4,5-b']二噻吩))-alt-(5,5-(1',3'-二-2-噻吩基-5',7'-双(2-乙基己基)苯并[1',2'-c:4',5'-c']二噻吩-4,8-二酮)]（PBDB-T））、低带隙受体（2,2'-((2Z,2'Z)-(((2,5-二氟-1,4-亚苯基)双(4,4-双(2-乙基己基)-4H-环戊并[2,1-b:3,4-b']二噻吩-6,2-二亚基))双(亚甲基))双(5,6-二氟-3-氧代-2,3-二氢-1H-茚-2,1-二亚基))二丙二腈（HF-PCIC））和近红外受体（2,2'-((2Z,2'Z)-(((4,4,9,9-四(4-己基苯基)-4,9-二氢-s-茚并[1,2-b:5,6-b']二噻吩-2,7-二亚基)双(4-((2-乙基己基)氧基)噻吩-5,2-二亚基))双(亚甲基))双(5,6-二氟-3-氧代-2,3-二氢-1H-茚-2,1-二亚基))二丙二腈（IEICO-4F））的三元共混实现了高效有机太阳能电池（OSC）。结果表明，将IEICO-4F第三组分引入PBDB-T:HF-PCIC共混物中，三元OSC的短路电流密度（）增加到23.46 mA cm，比二元器件提高了44%。显著的电流提升源于吸收范围的拓宽以及通过引入IEICO-4F组分实现的活性层形态优化。此外，由于带隙以下吸收导致的辐射复合以及添加IEICO-4F后的非辐射复合均减少，三元电池的能量损失（0.59 eV）比二元电池（0.80 eV）大幅降低。因此，功率转换效率从二元电池的8.82%显著提高到三元电池的11.20%。这项工作为在OSC中同时实现显著的电流增强和能量损失减轻提供了良好的示例，这将有助于进一步构建高效的三元OSC。
