Fabrication of White Polymer Light Emitting Diodes with ITO/PVK:PBD:DPVBi:DCJTB/Al Structure

White polymer light emitting diodes (PLEDs) with the configuration of ITO/PVK:PBD:DPVBi:DCJTB/Al were fabricated where indium tin oxide (ITO) was used as anode, poly(9-vinylcarbazole) (PVK) as polymeric host, 2-(4-biphenylyl)-5-phenyl- 1,3,4-oxadiazole (PBD) as electron- transporting molecule, 4,4´-bis(2,2-diphenylvinyl)-1,1,-biphenyl (DPVBi) as blue dopant, 4-(dicyanomethylene)-2-t-butyl- 6(1,1,7,7-tetramethyljulolidyl-9-enyl)-4H-pyran (DCJTB) as red dopant, and aluminium (Al) as cathode. The emitting layer was prepared using spin-coating technique. The white light emission was obtained through the combination of orange emission from DCJTB and the blue emission from DPVBi. The device using the 0.06 wt% DCJTB exhibited the CIE coordinates (0.38, 0.33) closest to the standard CIE coordinates for white light emission (0.33, 0.33) and its current turn-on voltage was approximately 13 V.