The Dependence of OLED External Efficiency on the Mass Concentration of Europium(III) Dispersed in PVK

A very sharp wavelength response and significant electroluminescence and high internal quantum efficiency makes rare earth complexes promising materials to produce OLED devices with high performance. In this work a three layer device has been investigated to study the influence of the mass concentration of an europium complex [Eu(DBM)3Phen] dispersed in poly(9-vinylcarbazole) [PVK], on the external efficiency.