一个四重玻里化多重共振发射器,具有用于窄带色-红色发射的帕拉/超原子异原子图案
Xiao-Chun Fan1, Feng Huang1, Hao Wu1
1Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu, 215123, P. R. China.
Angewandte Chemie (International ed. in English)
|July 11, 2023
概括
研究人员开发了一种新的-发射器,用于长波长,窄带有机发光二极管 (OLED). 这一突破为此类发射器实现了最窄的光谱宽度,提高了OLED的性能和效率.
科学领域:
- 材料科学 材料科学 材料科学
- 有机电子 有机电子
- 光物理学的光学物理学
背景情况:
- 长波长多重共振 (MR) 发射器面临着光谱扩展的挑战,限制了它们在半最大 (FWHM) 的全宽度.
- 在较长波长 (最大波长>570 nm) 的窄频发射 (FWHM <20 nm) 之前对于MR发射器来说是无法实现的.
研究的目的:
- 设计和合成一种新的长波长窄带多重共振 (MR) 发射器.
- 为了在色-红色光谱中实现20nm以下狭窄FWHM的发射.
- 研究这种发射器在有机发光二极管 (OLED) 中的潜力.
主要方法:
- 战略性地将多种 (B) / (N) 原子对嵌入到多环芳 (PAH) 骨架中.
- 理论计算以了解电子结构和排放特征.
- 有机发光二极管 (OLED) 装置的制造和特征.
主要成果:
- 一个概念验证发射器,B4N6-Me,实现了色红色发射和19 nm (70 meV) 的异常狭窄的FWHM.
- 这代表了任何长波长MR发射器报告的最窄的FWHM.
- 基于B4N6-Me的OLED显示了最先进的性能,包括窄带红色辐射 (27nm FWHM),最大外部量子效率 (EQE) 为35.8%,最小效率滚动 (28.4%EQE在1000cd m-2).
结论:
- 开发的B/N原子对的混合模式有效地克服了光谱扩展问题.
- 这一策略使得能够构建具有卓越性能的长波长窄带MR发射器.
- 这些发现为先进的长波长MR发射器和OLED应用提供了新的分子设计原则.
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