Optical and morphological investigation in interaction of dual dopants in poly(N-vinylcarzole)

In this paper, we investigated the effect of the optical and electrical properties in poly(N-vinylcarzole) (PVK) doped with two dyes 8-tris-hydroxyquinoline (Alq3) and 4-(dicyanom-ethylene)-2-t-butyl-6-(1,1,7,7-tetramethyljulolidyl-9-enyl)-4H-pyran (DCJTB) on the energy transfer and charge trapping processes. The phase separation in blend films at different doping concentration was also studied. The results indicate that there is certain interaction between Alq3 and DCJTB. It is the incorporation of DCJTB that untangled the aggregation of Alq3 owing to the interaction of de-mixing of DCJTB in Alq3 domains. But for higher doping concentration of DCJTB, new aggregation domain result in an isolate charge transport channel that decreases the electroluminescence (EL) operating voltage.