Temperature and Exciton Concentration Induced Excimer Emission of 4,4′-Bis(4′′-Triphenylsilyl) Phenyl-1,1′-Binaphthalene and Application for Sunlight-Like White Organic Light-Emitting Diodes

This paper demonstrates the influence of temperature, exciton concentration, and electron transportation layers on the excimer emission of a novel deep-blue material: 4,4′-bis(4′′-triphenylsilyl) phenyl-1,1′-binaphthalene (SiBN), by studying the photoluminescence and electroluminescence spectra of SiBN-based film. We have further developed sunlight-like and warm-light white organic light-emitting diodes (WOLEDs) with high efficiency and wide-range spectra, using SiBN and bis(2-phenylbenzothiozolato-N,C2′)iridium(acetylacetonate) (bt(2)Ir(acac)) as the blue excimer and yellow materials, respectively. The resulting device exhibited an excellent spectra overlap ratio of 82.9 % with sunlight, while the device peak current efficiency, external quantum efficiency, and power efficiency were 18.5 cd/A, 6.34 %, and 11.68 lm/W, respectively, for sunlight-like WOLEDs.