“Molecular Design of a Pure-Red Fluorescent Emitter Enabling Highly Efficient Organic Light-Emitting Diodes with 4.7% EQE”

Affordable organic compounds with light-emitting properties offer a unique platform for addressing key challenges in organic electronics. This study primarily focuses on the molecular design and synthesis of a fluorescent emitter, 4-(tert-butyl)-N-(4-(tert-butyl)phenyl)-N-(4-(3,7,8-triphenylpyrazino[2,3-g]quinoxalin-2-yl)phenyl)aniline (tDPA-PyrQx), featuring an electron-donating bis(4-(tert-butyl)phenyl)amine group on a pyrazino[2,3-g]quinoxaline acceptor. The emitter exhibits high thermal stability, strong absorption and emission, and pronounced aggregation-induced emission (AIE), with its photophysical characteristics well supported by DFT calculations. The tDPA-PyrQx-doped OLED device was fabricated by using vacuum deposition and exhibited pure red emission, delivering a maximum external quantum efficiency (EQE) of 4.7% and Commission Internationale de l’Eclairage (CIE) coordinates of (0.67, 0.37).