Lin Kaiwen, Wang Shiliang, Wang Zhenfeng, Yin Qingwu, Liu Xi, Jia Jianchao, Jia Xiao'e, Luo Peng, Jiang Xiaofang, Duan Chunhui, Huang Fei, Cao Yong
State Key Laboratory of Luminescent Materials and Devices, Institute of Polymer Optoelectronic Materials and Devices, South China University of Technology, Guangzhou, China.
Front Chem. 2018 Sep 4;6:328. doi: 10.3389/fchem.2018.00328. eCollection 2018.
In this work, a star-shaped planar acceptor named FTr-3PDI was synthesized via ring-fusion between truxene core and three bay-linked perylene diimide (PDI) branches. Compared to the unfused non-planar acceptor Tr-3PDI, FTr-3PDI exhibits better structural rigidity and planarity, as well as more effective conjugation between truxene core and PDI branches. As a result, FTr-3PDI shows up-shifted energy levels, enhanced light absorption coefficient, increased electron mobility, and more favorable phase separation morphology in bulk-heterojunction (BHJ) blend films as compared to Tr-3PDI. Consequently, FTr-3PDI afforded higher power conversion efficiency (PCE) in BHJ solar cells when blended with a polymer donor PTB7-Th. This work demonstrates that ring-fusion is a promising molecular design strategy to combine the merits of truxene and PDI for non-fullerene acceptors used in organic solar cells.
在这项工作中，通过均苯三酚核与三个湾区连接的苝二酰亚胺（PDI）支链之间的环融合反应，合成了一种名为FTr-3PDI的星形平面受体。与未融合的非平面受体Tr-3PDI相比，FTr-3PDI表现出更好的结构刚性和平面性，以及均苯三酚核与PDI支链之间更有效的共轭。结果，与Tr-3PDI相比，FTr-3PDI在本体异质结（BHJ）共混膜中显示出能级上移、光吸收系数增强、电子迁移率增加以及更有利的相分离形态。因此，当与聚合物给体PTB7-Th共混时，FTr-3PDI在BHJ太阳能电池中提供了更高的功率转换效率（PCE）。这项工作表明，环融合是一种很有前景的分子设计策略，可将均苯三酚和PDI的优点结合起来，用于有机太阳能电池中的非富勒烯受体。
