Optical Properties of Aluminumquinoline-Oxadiazole Codeposited Luminescent Layers

Abstract
Aluminumquinoline-oxadiazole (Alq3-PBD) codeposited layers, where the heterojunction of Alq3 and PBD is expected to possess type-I energy lineup, were fabricated by vacuum evaporation, and their optical properties were investigated. The results showed effective energy transfer from PBD to Alq3 followed by dominant emission from Alq3, even at the Alq3 concentration as low as about 1.5%. By using the Alq3-PBD codeposited layer as the emitting layer of electroluminescence (EL) devices, a successful increase in output power and quantum efficiency was observed compared to conventional EL structures.