School of Electrical Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-Ro, Yuseong-Gu, Daejeon, 34141, Republic of Korea.
Department of Chemistry and RNIS, Gyeongsang National University, Jinju, 660-701, Republic of Korea.
Sci Rep. 2023 Jan 25;13(1):1369. doi: 10.1038/s41598-023-27487-6.
Near-infrared organic light-emitting diodes (NIR OLEDs) with heavy metals are regularly reported due to the advantages of their various applications in healthcare services, veil authentication, and night vision displays. For commercial applications, it is necessary to look at radiance capacity (RC) instead of radiance because of power consumption. However, recent papers still reported only simple high radiance performance and do not look at device from the point of view of RC. To overcome this hurdle, we designed Ir(III)-based heteroleptic NIR materials with two types of auxiliary ligand. The proposed emitters achieve a highly oriented horizontal dipole ratio (Ir(mCPDTiq)tmd, complex 1: 80%, Ir(mCPDTiq)acac, complex 2: 81%) with a short radiative lifetime (1: 386 ns, 2: 323 ns). The device also shows an extremely low turn-on voltage (V) of 2.2 V and a high RC of 720 mW/sr/m/V. The results on the V and RC of the device is demonstrated an outstanding performance among the Ir(III)-based NIR OLEDs with a similar emission peak.
近红外有机发光二极管（NIR OLEDs）通常含有重金属，由于其在医疗服务、面纱认证和夜视显示器等各种应用中的优势，而被广泛报道。对于商业应用，由于功耗的原因，有必要考虑亮度（RC）而不是亮度。然而，最近的论文仍然只简单地报道了高亮度性能，而没有从 RC 的角度来看待设备。为了克服这一障碍，我们设计了基于 Ir(III)的杂化 NIR 材料，具有两种辅助配体。所提出的发射器实现了高度定向的水平偶极子比（Ir(mCPDTiq)tmd，复合物 1：80%，Ir(mCPDTiq)acac，复合物 2：81%）和较短的辐射寿命（1：386 ns，2：323 ns）。该器件还表现出极低的开启电压（V）为 2.2 V 和极高的 RC 为 720 mW/sr/m/V。该器件的 V 和 RC 结果在具有相似发射峰的基于 Ir(III)的 NIR OLED 中表现出卓越的性能。
