Using an embedded nanocomposite layer to increase color- conversion efficiency of organic light-emitting diodes

Abstract Down-conversion white organic light-emitting diodes (WOLEDs) have a significant advantage in generating stabilized white-light emissions, but still have room for further improvement in terms of color-conversion efficiency. We demonstrated that TiO 2 nanoparticles mixed with fluorescent dyes could be used to increase the absorption of dyes and thus boost the efficiency of color-conversion. WOLEDs with a nanocomposite color-conversion layer achieved high efficiencies of 12.3% (22.9 cd/A and 22.5 lm/W) and stable white-light emission. In addition, the EL spectra with different viewing angles are close to the ideal Lambertain curve. These outcomes indicate that the nanocomposite-based color-conversion possesses great potential for use in display and lighting applications.