High stability white organic light-emitting diode fabricated with the deposition of solvent premixed sources

This paper presents the characteristics of high-stability white organic light-emitting diodes (WOLEDs). For the preparation of WOLEDs with a single-emission layer (EML), the source materials of MADN, BCzVB, C6, and DCJTB were solvent premixed before evaporation. The structure of the WOLEDs was ITO/NPB (50 nm)/EML (40 nm)/Bphen (30 nm)/Al (200 nm). The materials that comprised the EML for dual- and tri-wavelength WOLEDs were MADN:BCzVB:DCJTB and MADN:BCzVB:C6:DCJTB, respectively. The energy transfer between the host and the dyes influenced the luminance efficiency and chromaticity coordinates of the devices. The maximum current efficiencies were 6.34 and 6.38 cd/A for the dual- and tri-wavelength WOLEDs, respectively. The efficiency of the WOLEDs was enhanced by C6 doping, although a slight variation in the chromaticity coordinates was observed, which was resulted from variations in the applied voltage. ► High-stability dual- and tri-wavelength WOLEDs were fabricated. ► Doped dyes were uniformly dispersed throughout the emission layer by means of solvent premixing. ► Energy transfer mechanisms influenced the efficiency and chromaticity of the devices. ► The efficiencies were 6.34 and 6.38 cd/A for the dual- and tri-wavelength WOLEDs, respectively.