Jung Su-Kyo, Heo Jin Hyuck, Lee Dae Woon, Lee Seung-Heon, Lee Seung-Chul, Yoon Woojin, Yun Hoseop, Kim Dongwook, Kim Jong H, Im Sang Hyuk, Kwon O-Pil
Department of Molecular Science and Technology, Ajou University, Suwon, 443-749, Republic of Korea.
Department of Chemical and Biological Engineering, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul, 136-713, Republic of Korea.
ChemSusChem. 2019 Jan 10;12(1):224-230. doi: 10.1002/cssc.201802234. Epub 2018 Nov 20.
A design strategy is proposed for electron-transporting materials (ETMs) with homochiral asymmetric-shaped groups for highly efficient non-fullerene perovskite solar cells (PSCs). The electron transporting N,N'-bis[(R)-1-phenylethyl]naphthalene-1,4,5,8-tetracarboxylic diimide (NDI-PhE) consists of two asymmetric-shaped chiral (R)-1-phenylethyl (PhE) groups that act as solubilizing groups by reducing molecular symmetry and increasing the free volume. NDI-PhE exhibits excellent film-forming ability with high solubility in various organic solvents [about two times higher solubility than the widely used fullerene-based phenyl-C -butyric acid methyl ester (PCBM) in o-dichlorobenzene]. NDI-PhE ETM-based inverted PSCs exhibit very high power conversion efficiencies (PCE) of up to 20.5 % with an average PCE of 18.74±0.95 %, which are higher than those of PCBM ETM-based PSCs. The high PCE of NDI-PhE ETM-based PSCs may be attributed to good film-forming abilities and to three-dimensional isotropic electron transporting capabilities. Therefore, introducing homochiral asymmetric-shaped groups onto charge-transporting materials is a good strategy for achieving high device performance.
本文提出了一种用于高效非富勒烯钙钛矿太阳能电池（PSC）的具有同手性不对称形状基团的电子传输材料（ETM）的设计策略。电子传输材料N，N'-双[（R）-1-苯乙基]萘-1，4，5，8-四羧酸二酰亚胺（NDI-PhE）由两个不对称形状的手性（R）-1-苯乙基（PhE）基团组成，这两个基团通过降低分子对称性和增加自由体积起到增溶基团的作用。NDI-PhE在各种有机溶剂中具有优异的成膜能力和高溶解度[在邻二氯苯中的溶解度比广泛使用的基于富勒烯的苯基-C-丁酸甲酯（PCBM）高约两倍]。基于NDI-PhE ETM的倒置PSC表现出非常高的功率转换效率（PCE），高达20.5%，平均PCE为18.74±0.95%，高于基于PCBM ETM的PSC。基于NDI-PhE ETM的PSC的高PCE可能归因于良好的成膜能力和三维各向同性电子传输能力。因此，在电荷传输材料上引入同手性不对称形状基团是实现高器件性能的良好策略。
