White Electroluminescence from Aluminum Zinc Oxide Embedded in Poly(9‐vinylcarbazole)

Abstract

Simple methods for manufacturing white light‐emitting diodes (WLEDs) based on ZnO are still challenging researchers. Solution processed WLEDs based on Al doped ZnO (AZO) nanoparticles embedded in PVK (hybrid system) are demonstrated here, and PL studies of the hybrid system suggest that defects in AZO and PVK/AZO interface are likely to be the origin of white EL. Besides electrical conductivity increment, AZO provided the emissive layer with a more balanced charge injection; thus, the threshold voltage reduced from 8.1 V to 7.5 V and EL enhanced from 4.47 cd/m2 to 18.69 cd/m2 at 10 V, for the pure PVK compared to the hybrid system, respectively.