Achieving Pure Green Electroluminescence with CIEy of 0.69 and EQE of 28.2% from an Aza‐Fused Multi‐Resonance Emitter
Yuewei Zhang, Dongdong Zhang, Jinbei Wei, Xiangchen Hong, Yangcheng Lü, Deping Hu, Guomeng Li, Ziyang Liu, Chen Yang, Lian Duan
Abstract
Abstract Pure green emitters are essential for realizing an ultrawide color gamut in next‐generation displays. Herein, by fusing the difficult‐to‐access aza‐aromatics onto B (boron)–N (nitrogen) skeleton, a hybridized multi‐resonance and charge transfer (HMCT) molecule AZA‐BN was successfully synthesized through an effective one‐shot multiple cyclization method. AZA‐BN shows pure green fluorescence with photoluminance quantum yield of 99.7 %. The corresponding green device exhibits a maximum external quantum efficiency and power efficiency of 28.2 % and 121.7 lm W −1 , respectively, with a full width half maximum (FWHM) of merely 30 nm and Commission Internationale de l'Eclairage (CIE) coordinate y of 0.69, representing the purest green bottom‐emitting organic light‐emitting diode.