Organic Light-Emitting Diodes Based on New Oxadiazole and Pyrazoline Derivatives

The bilayer heterojunction devices were fabricated successfully by using a novel oxadiazole derivative: 2, 2'- (2,5-thiophenediyl) bis (5-(4-methyl) phenyl-l,3,4-oxadiazole) (T-OXD) as the electron-transporting layer (ETL) and a pyrazoline derivative:l-phenyl-3-(dimethylamino)styry1-5-(p(dimethylamino) pheny1)pyrazoline (PDP) as the light-emitting layer and the hole-transporting layer. The emission at 500nm was derived from PDP layer. In comparison with the bilayer device of tris (8-hydroxyquinoline) aluminum (Alq) as the ETL, the luminous efficiency of the PDP/T-OXD heterojunction device was enhanced by 10⁴ times.