Design and synthesis of fast kRISC MR-TADF emitters: merge of cycloparaphenylene materials and B,O doped MR-TADF emitters (CPP-MR-TADF)

快速 kRISC MR-TADF 发射器的设计和合成：环对亚苯基材料和 B,O 掺杂 MR-TADF 发射器的合并 (CPP-MR-TADF)

• 批准号: EP/Y01037X/1
• 负责人: Eli Zysman-Colman
• 金额: $ 23.84万
• 依托单位: University of St Andrews
• 依托单位国家: 英国
• 项目类别: Fellowship
• 财政年份: 2023
• 资助国家: 英国
• 起止时间: 2023 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FY01037X%2F1
• 关键词: Design; synthesis; fast; kRISC; MR

Organic light-emitting diodes (OLEDs) are nowadays omnipresent in the form of display screens in mobile phones and smartwatches. Although already commercialized, this technology still possesses shortcomings. For instance, OLEDs use scarce noble metals like iridium as emitters for the red and green pixels of the display, making the technology in its present form not sustainable. Introduced for the first time in 2015, multiresonant thermally activated delayed fluorescence (MR-TADF) emitters, which are organic compounds, allow to produce OLEDs at comparable efficiency and color point to phosphorescent OLEDs, but are sustainable. However, OLEDs with MR-TADF materials presently suffer from a too high efficiency roll-off related to the slow reverse intersystem crossing rate (kRISC), strong intermolecular interactions/aggregation that cause emission quenching, and poor charge transport properties. This project proposes the development of a new class of luminescent materials that brings together facets of MR-TADF emitters and cycloparaphenylene (CPP) materials. CPPs are pure hydrocarbon organic semiconductors that possess a cylindrical geometry, which strongly limits intermolecular interactions in the solid state. This fundamental proposal explores the theoretical modelling, synthesis, and optoelectronic characterization of a family of hybrid CPP-MR-TADF materials as potential emitters for OLEDs. The proposed multidisciplinary strategy aims to provide a sought-after solution to increasing kRISC in MR-TADF materials while also addressing issues of charge transport in the emissive layer and the propensity for these molecules to undesirably aggregate.

有机发光二极管(OLED)如今在手机和智能手表中以显示屏的形式无处不在。虽然这项技术已经商业化，但仍有缺点。例如，有机发光二极管使用稀有的贵金属，如Ir，作为显示器的红色和绿色像素的发射器，使得目前的技术形式不可持续。2015年首次推出的多共振热激活延迟荧光(MR-TADF)发射器是一种有机化合物，可以以与磷光OLED相当的效率和色点生产OLED，但是可持续的。然而，目前采用MR-TADF材料的OLED存在效率过高的问题，原因是反向系统间交叉速率(KRISC)较慢，分子间强相互作用/聚集导致发射猝灭，以及较差的电荷传输特性。该项目提出了一种新型发光材料的开发，该材料将MR-TADF发射器的小面和环芳烃(CPP)材料结合在一起。CPP是一种纯烃有机半导体，具有圆柱形几何结构，这强烈限制了固态中分子间的相互作用。这一基本方案探索了一类作为有机发光器件潜在发光体的CPP-MR-TADF杂化材料的理论建模、合成和光电特性。拟议的多学科战略旨在提供一种广受欢迎的解决方案，以增加MR-TADF材料中的kRISC，同时还解决发射层中的电荷传输问题和这些分子意外聚集的倾向。