Conaghan Patrick J, Matthews Campbell S B, Chotard Florian, Jones Saul T E, Greenham Neil C, Bochmann Manfred, Credgington Dan, Romanov Alexander S
Cavendish Laboratory, Department of Physics, University of Cambridge, J J Thomson Avenue, CB3 0HE, Cambridge, UK.
School of Chemistry, University of East Anglia, Earlham Road, Norwich, NR4 7TJ, UK.
Nat Commun. 2020 Apr 9;11(1):1758. doi: 10.1038/s41467-020-15369-8.
Carbene-metal-amides are soluble and thermally stable materials which have recently emerged as emitters in high-performance organic light-emitting diodes. Here we synthesise carbene-metal-amide photoemitters with CF-substituted ligands to show sky-blue to deep-blue photoluminescence from charge-transfer excited states. We demonstrate that the emission colour can be adjusted from blue to yellow and observe that the relative energies of charge transfer and locally excited triplet states influence the performance of the deep-blue emission. High thermal stability and insensitivity to aggregation-induced luminescence quenching allow us to fabricate organic light-emitting diodes in both host-free and host-guest architectures. We report blue devices with a peak external quantum efficiency of 17.3% in a host-free emitting layer and 20.9% in a polar host. Our findings inform the molecular design of the next generation of stable blue carbene-metal-amide emitters.
卡宾-金属酰胺是可溶且热稳定的材料，最近已成为高性能有机发光二极管中的发光体。在此，我们合成了带有CF取代配体的卡宾-金属酰胺光发射体，以展示从电荷转移激发态发出的天蓝色至深蓝色光致发光。我们证明发射颜色可从蓝色调节至黄色，并观察到电荷转移和局域激发三重态的相对能量会影响深蓝色发射的性能。高热稳定性以及对聚集诱导发光猝灭的不敏感性，使我们能够制造无主体和主体-客体结构的有机发光二极管。我们报道了在无主体发光层中峰值外量子效率为17.3%、在极性主体中为20.9%的蓝色器件。我们的研究结果为下一代稳定的蓝色卡宾-金属酰胺发光体的分子设计提供了依据。
