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Approaching Ohmic hole contact via a synergetic effect of a thin insulating layer and strong electron acceptors

基于薄绝缘层和强电子受体的协同效应实现近似 欧姆接触的高效空穴注入策略

摘要

有效的电荷注入是发展低电压、高效率有机发光二极管 (OLEDs)的关键. 然而, 目前应用最广泛的空穴注入材料(HATCN) 的注入效率仅约10%, 无法满足高清显示和照明的需要. 因此, 我们 基于薄绝缘层(特氟龙(Teflon))和强电子受体(HATCN)的协同效 应设计了一种高效、通用的空穴注入技术. 研究表明特氟龙诱导 形成的纳米岛状结构有助于增强界面电场局域化, 搭配HATCN可 以实现高效的电荷产生和空穴注入. 新型的注入层(Teflon/HATCN)可实现近似欧姆接触的高效空穴注入, 其注入效率高达 80%以上. 基于该方法制备的红色磷光OLED的启亮电压仅为2.4 V, 最大外量子效率高达33.1%. 本文关于薄绝缘层和强电子受体的协 同效应的研究为发展高性能电荷注入材料提供了新策略.

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Acknowledgements

This work was supported by the National Key Basic Research and Development Program of China (2017YFA0204501 and 2020YFA0715000), the National Natural Science Foundation of China (51903137 and 61890942), and Foshan Xianhu Laboratory of the Advanced Energy Science and Technology Guangdong Laboratory (XHT2020-005). Zhang D also thanks the financial support from the Young Elite Scientist Sponsorship Program (2019QNRC001) by China Association for Science and Technology.

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Authors

Contributions

Duan L conceived and supervised the project. Zhang D and Duan L proposed and designed the experiments. Liu Z carried out the UPS analysis and measured the hole-only devices. Wei P conducted the characterization of c-AFM and red PhOLEDs. Liu Z and Wei P wrote the manuscript. Bin Z, Wang X, Zhang D, and Duan L discussed the results and revised the manuscript.

Corresponding authors

Correspondence to Dongdong Zhang or Lian Duan.

Additional information

Ziyang Liu is currently a PhD candidate at the Department of Chemistry, Tsinghua University, under the supervision of Prof. Lian Duan. His research focuses on charge injection materials for organic light-emitting diodes.

Dongdong Zhang received his PhD degree from the Department of Chemistry, Tsinghua University, in 2016, under the supervision of Prof. Yong Qiu and Prof. Lian Duan. Then he works in the group. His research interest focuses on developing new organic materials for organic electronics.

Lian Duan received his PhD degree from the Department of Chemistry, Tsinghua University, in 2003. He is currently a full professor at the Department of Chemistry, Tsinghua University. His research focuses on organic materials and device physics for optoelectronic devices, including organic light-emitting diodes, perovskite light-emitting diodes, and perovskite solar cells.

Conflict of interest

The authors declare that they have no conflict of interest.

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Liu, Z., Wei, P., Bin, Z. et al. Approaching Ohmic hole contact via a synergetic effect of a thin insulating layer and strong electron acceptors. Sci. China Mater. 64, 3124–3130 (2021). https://doi.org/10.1007/s40843-021-1787-3

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