Chen Kaixuan, Wei Huan, Chen Ping-An, Liu Yu, Guo Jing, Xia Jiangnan, Xie Haihong, Qiu Xincan, Hu Yuanyuan
Key Laboratory for Micro/Nano Optoelectronic Devices of Ministry of Education & International Science and Technology Innovation Cooperation Base for Advanced Display Technologies of Hunan Province, School of Physics and Electronics, Hunan University, Changsha, 410082, China.
Shenzhen Research Institute of Hunan University, Shenzhen, 518063, China.
Front Optoelectron. 2022 May 26;15(1):26. doi: 10.1007/s12200-022-00019-2.
The recently reported non-fullerene acceptor (NFA) Y6 has been extensively investigated for high-performance organic solar cells. However, its charge transport property and physics have not been fully studied. In this work, we acquired a deeper understanding of the charge transport in Y6 by fabricating and characterizing thin-film transistors (TFTs), and found that the electron mobility of Y6 is over 0.3-0.4 cm/(V⋅s) in top-gate bottom-contact devices, which is at least one order of magnitude higher than that of another well-known NFA ITIC. More importantly, we observed band-like transport in Y6 spin-coated films through temperature-dependent measurements on TFTs. This is particularly amazing since such transport behavior is rarely seen in polycrystalline organic semiconductor films. Further morphology characterization and discussions indicate that the band-like transport originates from the unique molecule packing motif of Y6 and the special phase of the film. As such, this work not only demonstrates the superior charge transport property of Y6, but also suggests the great potential of developing high-mobility n-type organic semiconductors, on the basis of Y6.
最近报道的非富勒烯受体（NFA）Y6已被广泛研究用于高性能有机太阳能电池。然而，其电荷传输特性和物理机制尚未得到充分研究。在这项工作中，我们通过制备和表征薄膜晶体管（TFT）对Y6中的电荷传输有了更深入的了解，发现在顶栅底接触器件中Y6的电子迁移率超过0.3 - 0.4 cm/(V⋅s)，这比另一种著名的NFA ITIC至少高一个数量级。更重要的是，我们通过对TFT进行温度相关测量，在Y6旋涂膜中观察到了带状传输。这尤其令人惊讶，因为这种传输行为在多晶有机半导体薄膜中很少见。进一步的形态表征和讨论表明，带状传输源于Y6独特的分子堆积模式和薄膜的特殊相态。因此，这项工作不仅证明了Y6优异的电荷传输特性，还表明了基于Y6开发高迁移率n型有机半导体的巨大潜力。
