近日，清华大学的段炼教授&张东东研究员及其研究团队取得一项新进展。经过不懈努力，他们成功通过渗透策略增强蓝色热激活延迟荧光发射器的效率和稳定性。相关研究成果已于2024年1月29日在国际知名学术期刊《自然—光子学》上发表。
该研究团队采用了一种分子渗透策略，成功稳定了蓝色热激活延迟荧光（TADF）发射器。这种策略通过抑制高能振动，显著提高了氘化天蓝色TADF发射体在OLED中的效率和器件寿命，是质子化发射体的两倍。在固态条件下，分子渗透还会导致光谱的蓝移和变窄，这有助于改善在TADF敏化荧光OLED中，Frster能量向深蓝色最终发射器的转移。
这些器件的最大外部量子效率达到33.1%，在1000 cdm-2的亮度下，寿命达到了初始亮度1365 h的80%，国际照明委员会y坐标为0.20，甚至超越了传统的蓝色磷光OLED。这一分子渗透策略显著提升了蓝色OLED的器件性能，为其在显示器和照明领域的更广泛应用奠定了基础。
据悉，尽管高效、稳定的蓝色有机发光二极管（OLED）是显示和照明应用所必需的，但目前市场上仍然很少见。
附：英文原文
Title: Enhancing the efficiency and stability of blue thermally activated delayed fluorescence emitters by perdeuteration
Author: Huang, Tianyu, Wang, Qi, Zhang, Hai, Zhang, Yuewei, Zhan, Ge, Zhang, Dongdong, Duan, Lian
Issue&Volume: 2024-01-29
Abstract: Highly efficient and stable blue organic light-emitting diodes (OLEDs), although required for display and lighting applications, remain rare. Here we report a molecular perdeuteration strategy to stabilize blue thermally activated delayed fluorescence (TADF) emitters. Perdeuterated sky-blue TADF emitters exhibit higher efficiencies and doubled device lifetime in OLEDs compared with protonated emitters, owing to suppressed high-energy vibrations. Perdeuteration also leads to blue-shifted and narrowed spectra in the solid state, which in turn improves the Frster energy transfer to the deep-blue final emitter in TADF-sensitized fluorescent OLEDs. These devices exhibit a maximum external quantum efficiency of 33.1% and a lifetime to reach 80% of the initial luminance of 1,365h with a Commission Internationale de l’Eclairage y coordinate of 0.20 at a luminance of 1,000cdm-2, even outperforming blue phosphorescent OLEDs. Our perdeuteration strategy improves the device performance of blue OLEDs, paving the way for their broader applications in displays and lightings.
DOI: 10.1038/s41566-024-01379-1
Source: https://www.nature.com/articles/s41566-024-01379-1