作者:Jung Hei Choi、Kyung-In Son、Taehee Kim、Kyungkon Kim、Kei Ohkubo、Shunichi Fukuzumi
DOI:10.1039/b916597e
日期:——
A series of thienyl-substituted methanofullerenes as electron acceptors for bulk-heterojuction solar cells with poly(3-hexylthiophene) (P3HT) were synthesized and characterized with respect to electrochemical and photophysical properties. The first one-electron reduction potentials of the higher adducts are shifted toward more negative values by ∼100 mV as compared to the monoadduct. As a result, the solar cells composed of the bisadduct (2) and trisadduct exhibit a larger open-circuit voltage (Voc) than the solar cell composed of P3HT and [6,6]-phenyl-C61-butyric acid methyl ester (PCBM), as they have higher LUMO energy levels. Photophysical studies on spin-coated films by femtosecond laser flash photolysis indicate that ultrafast electron transfer from the P3HT donor polymer to all of the fullerene derivatives occurs to form the bound radical pair (BRP) state. No decay of the BRP state of P3HT:thienyl-substituted monoadduct (1) films was observed in the time range of 3 ns. The AFM investigation on P3HT:1 and P3HT:higher adduct films after thermal annealing showed fine donor and acceptor domains and larger domains, respectively. The bulk-heterojunction (BHJ) solar cells based on P3HT:1 exhibited a power conversion efficiency (PCE) of 3.97%, which is comparable with that of the P3HT:PCBM cell. The P3HT:2 based cell showed a PCE value of 1.72% with a higher open-circuit voltage of 0.72 V.
合成了一系列噻吩基取代的亚甲基富勒烯作为电子受体,用于聚(3-己基噻吩)(P3HT)本体异质结太阳能电池,并对其电化学和光物理性质进行了表征。与单加合物相比,较高加合物的第一单电子还原电位向更负的值移动~100 mV。结果,由双加合物(2)和三加合物组成的太阳能电池表现出比由P3HT和[6,6]-苯基-C61-丁酸甲酯(PCBM)组成的太阳能电池更大的开路电压(Voc)。 ),因为它们具有更高的 LUMO 能级。通过飞秒激光闪光光解对旋涂薄膜进行的光物理研究表明,发生从 P3HT 供体聚合物到所有富勒烯衍生物的超快电子转移,形成结合自由基对 (BRP) 态。在 3 ns 的时间范围内没有观察到 P3HT:噻吩基取代的单加合物 (1) 薄膜的 BRP 态衰减。热退火后 P3HT:1 和 P3HT: 高加合物薄膜的 AFM 研究分别显示出精细的供体和受体域以及较大的域。基于P3HT:1的体异质结(BHJ)太阳能电池的功率转换效率(PCE)为3.97%,与P3HT:PCBM电池相当。基于 P3HT:2 的电池的 PCE 值为 1.72%,开路电压高达 0.72 V。