Abstract
White organic light-emitting diodes (WOLEDs) based on non-doped single emitter can promise convenient fabrication technology, absent phase separation, minimal color-aging, and good reproducibility for next-generation displays and lightings. However, the pure organic materials that could radiate intense white light are extremely rare, and the external quamtum efficiencies (EQE) of previously reported non-doped white OLEDs do not exceed 5%. Hence, the straightforward preparation of single white light-emitting molecules for high-performance non-doped WOLEDs remains a high challenging task. Herein, we design and synthesize four hot exciton materials, PhAnPy, DPhAnPy, PIAnPy and PyIAnPy, which consist of anthracene, pyrene and imidazole functional groups. Based on the rational manipulation of intermolecular interaction and excited state property, PIAnPy and PyIAnPy display dual emission in the neat films originating from the monomer and excimer emission. Exploiting PIAnPy as a single emitter, a non-doped WOLED is fabricated with a record EQE of 10.14%, a maximum luminance exceeding 50000 cd m-2 and the Commission Internationale de L'Eclairage coordinates of (0.35, 0.26). Its EQE maintains as high as 9.80% at the luminescence of 1000 cd m-2 showing a very low efficiency roll-off. To the best of our knowledge, this is the best results of non-doped WOLEDs based on the single-component emitters reported to date.