Zhou Huayi, Wang Runze, Sun Mizhen, Zhou Yannan, Zhang Li, Song Jingru, Sun Qikun, Zhang Shi-Tong, Yang Wenjun, Xue Shanfeng
Key Laboratory of Rubber-Plastics of the Ministry of Education, School of Polymer Science & Engineering, Qingdao University of Science and Technology Qingdao 266042 P. R. China
State Key Laboratory of Supramolecular Structure and Materials, Institute of Theoretical Chemistry, College of Chemistry, Jilin University Changchun 130012 P. R. China
Chem Sci. 2024 Oct 9;15(44):18601-7. doi: 10.1039/d4sc05625f.
The lack of blue-emissive materials with high efficiency and excellent color purity commonly represents a pivotal obstacle in the development of organic light-emitting diodes (OLEDs). In this work, two blue to near-ultraviolet (NUV) donor-π-acceptor (D-π-A) emitters based on a fluorene π-bridge, 9-PCZCFTZ and 3-PCZCFTZ, are thus designed and synthesized, and non-doped devices derived from these two materials exhibit electroluminescence (EL) emission peaks at 404 nm and 417 nm, respectively. Interestingly, due to the specific stacking, a phenomenon appears in both materials in which the mobility of the electron is much higher than that of the hole, prompting us to use host doping to increase the hole mobilities, which ultimately leads to excellent OLED performances. As a result, the maximum external quantum efficiency (EQE) values of 9-PCZCFTZ and 3-PCZCFTZ in the doped devices reach as high as 14.5% and 10.8% respectively. Notably, both OLEDs show high blue purity very close to the BT.2020 standard.
缺乏高效且色纯度优异的蓝光发射材料通常是有机发光二极管（OLED）发展中的一个关键障碍。在这项工作中，基于芴π桥设计并合成了两种蓝色至近紫外（NUV）供体-π-受体（D-π-A）发光体9-PCZCFTZ和3-PCZCFTZ，由这两种材料制成的非掺杂器件分别在404 nm和417 nm处表现出电致发光（EL）发射峰。有趣的是，由于特定的堆积方式，两种材料中均出现电子迁移率远高于空穴迁移率的现象，促使我们采用主体掺杂来提高空穴迁移率，最终实现了优异的OLED性能。结果，掺杂器件中9-PCZCFTZ和3-PCZCFTZ的最大外量子效率（EQE）值分别高达14.5%和10.8%。值得注意的是，两种OLED均显示出非常接近BT.2020标准的高蓝光纯度。
