Warm-White Hyperfluorescent Organic Light Emitting Diodes based on Complementary Color Emission

Paving the way for the next generation of display technologies are organic lightemitting diodes (OLEDs), a leader in technological innovation. Despite significant advancements, developing white OLEDs (WOLEDs) with simultaneously high color purity, long operational lifetime, and high efficiency remains a formidable challenge. The core of our strategy to tackle this challenge was the development of a dual-color hyperfluorescent OLED that incorporated thermally activated delayed fluorescence (TADF) materials. This will enable the device to deliver excellent warm-white light performance. This architecture employs DMAC-DPS as the TADF sensitizer, with TBPe and PO-01-TB serving as the blue and yellow emitters, respectively. The structure of blue layer was DPEPO:40% DMAC-DPS:1% TBPe(20 nm) and the ultra-thin phosphor PO-01-TB(0.1 nm) was used as the yellow light layer. By optimizing the device structure, high-performance warmwhite OLED had been obtained. The maximum power efficiency (PE) and external quantum efficiency (EQE) of the device are 31.86% lm W -1 and 13.54%, respectively. At a brightness of 1000 cd m -2 , the Commission International de I’Eclairage (CIE) of (0.46, 0.50). When the brightness increases from 1 cd m -2 to the maximum value of 638 coordinates 2 cd m -2 , the CIE coordinates only change from (0.46, 0.50) to (0.44, 0.49), with very little variation. Implemented warm white light emission. The high performance of the device is attributed to its hyperfluorescent structure.