Preparation and Characterization of White Phosphorescence Polymer Light Emitting Diodes Using PFO:Ir(ppy)₃:MDMO-PPV Emission Layer

White phosphorescence polymer light emitting diodes (WPhPLEDs) with a glass/ITO/PEDOT:PSS/PFO:Ir(ppy)₃:MDMO-PPV/TPBI/LiF/Al structure were fabricated to investigate the effects of Ir(ppy)₃ doping concentrations on the optical and electrical properties of the devices. PFO, Ir(ppy)₃ and MDMO-PPV conjugated polymers as host and guest materials in the emission layer were spin coated at various concentrations of Ir(ppy)₃ ranging from 0.0 to 20.0 vol.%. As the concentration of Ir(ppy)₃ increased from 5.0 to 20.0 vol.%, the luminance and current efficiency values of the devices decreased clearly, which are attributable to the quenching effect at a high doping concentration. The maximum luminance and current density were 2850 cd/m² and 741 mA/cm², respectively for a WPhPLED with an Ir(ppy)₃ concentration of 5.0 vol.%. The CIE color coordinates were about x=0.33 and y=0.34 at 11V, showing a good white color.