Bright red light-emitting organic electroluminescent devices based on a novel thiophene-containing europium complex as an emitting layer

Abstract

A novel europium complex, Eu(DTP)₃(dipphen) (DTP = 1,3-di(2-thienyl)propane-1,3-dione, dipphen = 4,7-diphenyl-1,10-phenanthroline), has been synthesized and applied to organic electroluminescent (EL) devices as an emitting and electron-transporting material. The EL device structure can be described as indium tin oxide (ITO)/hole-transporting layer (triphenyldiamine derivative (TPD))/emitting layer (Eu(DTP)₃(dipphen))/electron transport layer (Alq3)/AlLi (99∶1). The emitting layers were formed by a codeposition technique. The deposited EL devices were observed to emit a bright red light originating from Eu(DTP)₃(dipphen) with a maximum luminance of 450 cd m^–2 at 15 V and 200 mA cm^–2.