Organic light-emitting devices (OLEDs) have been an important subject in recent years due to their applications in displays and electronic industries [1-3]. Furthermore, blue light- emitting materials have been essential because of their wild applicability [4-7]. Adachi, et al. reported 2-(biphenyl-4-yl)-5-(4-tert-butylphenyl)-1, 3, 4-oxadiazole (PBD) as an excellent electron transport material (ETM) in an organic multilayer electroluminescent (EL) diode [8 ...