Rajendran Vignesh, Erulappan Jeyasurya, Thomas K R Justin
Department of Chemistry, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand, 247667, India.
Chem Asian J. 2025 Jun;20(12):e202500254. doi: 10.1002/asia.202500254. Epub 2025 May 1.
The development of organic light-emitting diodes (OLEDs) has witnessed remarkable progress in material design and device architecture. Recent advancements, particularly in the fourth generation of OLEDs, have introduced groundbreaking innovations such as hyperfluorescence and multiresonance (MR) thermally activated delayed fluorescence (MRTADF) emitters. Carbazole has emerged as a versatile scaffold, playing a pivotal role in conventional fluorescence, TADF, roomtemperature phosphorescence (RTP), and MRTADF systems. In recent years, fused carbazole derivatives have gained significant attention as both emitting and host materials in OLEDs. The fusion of carbazole units enhances molecular rigidity and extends the πconjugation, enabling precise tuning of optoelectronic properties across a wide color gamut, including blue, green, orange, yellow, and red emissions. This review systematically explores the application of various fused carbazole systems such as indolocarbazole, thienocarbazole, furocarbazole, indenocarbazole, triazatruxene, acridinecarbazole, chromenocarbazole, pyrenocarbazole, helicene carbazole, and carbazolefused boron/carbonyl MRTADF emitters in OLEDs. The discussion is organized into three sections based on their application in blue, green, and red OLEDs, providing a comprehensive understanding of structure-property relationships. Additionally, other color-emitting OLEDs are discussed where relevant, offering a holistic perspective on the potential of fused carbazole derivatives in next-generation OLED technologies.
有机发光二极管（OLED）的发展在材料设计和器件结构方面取得了显著进展。最近的进展，特别是在第四代OLED中，引入了诸如超荧光和多共振（MR）热激活延迟荧光（MRTADF）发射体等突破性创新。咔唑已成为一种通用的骨架，在传统荧光、热激活延迟荧光（TADF）、室温磷光（RTP）和MRTADF系统中发挥着关键作用。近年来，稠合咔唑衍生物作为OLED中的发光材料和主体材料受到了广泛关注。咔唑单元的稠合增强了分子刚性并扩展了π共轭，从而能够在包括蓝色、绿色、橙色、黄色和红色发射在内的广泛色域中精确调节光电性能。本文综述系统地探讨了各种稠合咔唑体系，如吲哚并咔唑、噻吩并咔唑、呋喃并咔唑、茚并咔唑、三氮杂三聚茚、吖啶并咔唑、色烯并咔唑、芘并咔唑、螺旋烯咔唑以及咔唑稠合硼/羰基MRTADF发射体在OLED中的应用。讨论根据它们在蓝色、绿色和红色OLED中的应用分为三个部分，全面理解结构-性能关系。此外，还讨论了其他发光颜色的OLED，全面介绍了稠合咔唑衍生物在下一代OLED技术中的潜力。
