High-Quality White Organic Light-Emitting DiodesComposed of Binary Emitters with Color Rendering IndexExceeding 80 by Utilizing Color Remedy Strategy
Xun Tang1, Xiang-Yang Liu1, Zuo-Quan Jiang1,*, and Liang-Sheng Liao1,2,*
1Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, 199 Ren’ai Road, Suzhou, Jiangsu 215123, P. R. China
2Institute of Organic Optoelectronics Jiangsu Industrial Technology Research Institute (JITRI), Wujiang, Suzhou, Jiangsu 215211, P. R. China
Implementing rigorous standards for high-quality white organic light-emittingdiodes (WOLEDs) demands further investigation. Herein, a novel and feasiblecolor remedy strategy (CRS) is proposed in WOLEDs composed of binary emitters,to arouse the green-emission, thereby complementing the spectraldeficiency in white-emission. Thus, the color rendering indexes (CRIs) ofbinary-emissive WOLEDs can be boosted from 63 to 80 threshold, and theCommission International de I’Eclairage-(x, y) coordinates are preciselylocated inside the American National Standard Institute quadrangles, whichcan rival the WOLEDs integrating ternary or more emitters. Moreover, it ismore feasible for CRS-based binary-emissive system to tune white-emission from cool white-emission (correlated color temperature (CCT)≈5000 K) to eye-friendly warm white-emission (CCT≈2000 K). Meanwhile, benefiting from the reduced energy loss and low driving voltage of CRS zone, all of theCRS-based WOLEDs with diverse CCTs can exceed 20% external quantumefficiency, and the highest approach 25%, as well as the highest power efficiencybeyond 60 lm W-1, which is comparable with those reported employing light extractingtechniques. In addition, it is evident that CRS-based WOLEDs alsoexhibit outstanding color stability within the variation of luminance in severalorders of magnitude (50–12 000 cd m-2). Thus, this novel CRS provides aninnovative pathway to fabricate high-quality WOLEDs composed of binaryemitters.