摘要
The ternary strategy for incorporating multiple photon-sensitive components into a single junction has emerged as an effective method for optimizing the nanoscale morphology and improving the device performance of organic solar cells （OSCs）.In this study,efficient and stable ternary OSCs were achieved by introducing the small-molecule dye （5E,5＆#39;E）-5,5＆#39;-（4＆#39;,4″-（1,2-diphenylethene-1,2-diyl）bis（biphenyl-4＆#39;,4-diyl））bis（methan-1-yl-1-ylidene）bis（3-ethyl-2-thioxothia zolidin-4-one） （BTPERn） into poly[4,8-bis（5-（2-ethylhexyl）thiophen-2-yl）benzo[1,2-b：4,5-b＆#39;]dithiopheneco-3-fluorothieno[3,4-b]thiophene-2-carboxylate] （PTB7-Th）：[6,6]-phenyl C71 butyric acid methyl ester （PC71BM） blend films processed using a 1,8-diiodooctane （DIO）-free solvent.The incorporation of BTPE-Rn enhanced the short-circuit current density and fill factor of the ternary OSCs compared with those of binary OSCs.An investigation of the optical,electronic,and morphological properties of the ternary blends indicated that the third component of BTPE-Rn not only promoted the photon utilization of blends through the energy-transfer process but also improved the electron mobility of the blends owing to the fullerene-rich nanophase optimization.More importantly,this ternary strategy of utilizing a small-molecule dye to replace the photounstable DIO additive enhanced the operational stability of the OSCs.
The ternary strategy for incorporating multiple photon-sensitive components into a single junction has emerged as an effective method for optimizing the nanoscale morphology and improving the device performance of organic solar cells （OSCs）.In this study,efficient and stable ternary OSCs were achieved by introducing the small-molecule dye （5E,5＆#39;E）-5,5＆#39;-（4＆#39;,4″-（1,2-diphenylethene-1,2-diyl）bis（biphenyl-4＆#39;,4-diyl））bis（methan-1-yl-1-ylidene）bis（3-ethyl-2-thioxothia zolidin-4-one） （BTPERn） into poly[4,8-bis（5-（2-ethylhexyl）thiophen-2-yl）benzo[1,2-b：4,5-b＆#39;]dithiopheneco-3-fluorothieno[3,4-b]thiophene-2-carboxylate] （PTB7-Th）：[6,6]-phenyl C71 butyric acid methyl ester （PC71BM） blend films processed using a 1,8-diiodooctane （DIO）-free solvent.The incorporation of BTPE-Rn enhanced the short-circuit current density and fill factor of the ternary OSCs compared with those of binary OSCs.An investigation of the optical,electronic,and morphological properties of the ternary blends indicated that the third component of BTPE-Rn not only promoted the photon utilization of blends through the energy-transfer process but also improved the electron mobility of the blends owing to the fullerene-rich nanophase optimization.More importantly,this ternary strategy of utilizing a small-molecule dye to replace the photounstable DIO additive enhanced the operational stability of the OSCs.
基金
The authors thank the financial support from the National Basic Research Program of China （No. 2014CB643503）. The work was also partly supported by the National Natural Science Foundation of China （Nos. 21474088 and 21674093）. F. L. and C. Z. L. thank the support from Young 1000 Talents Global Recruitment Program of China. T. P. R. were supported by the U.S. Office of Naval Research under contract N00014-15-1- 2244. Portions of this research were carried out at beamline 7.3.3 and 11.0.1.2 at the Advanced Light Source, Molecular Foundry, and National Center for Electron Microscopy, Lawrence Berkeley National Laboratory, which was supported by the DOE, Office of Science, and Office of Basic Energy Sciences.
