Ligand-assisted synthesis of monodispersed and small-sized ZnO nanoparticles and their application in electroluminescence device

Abstract

ZnO nanoparticle thin film has been demonstrated to be the best electron transportation material in quantum dot-based light emitting diodes (QD-LEDs). Therefore, the synthesis of well-dispersed and size-controllable ZnO nanoparticles is highly desirable. In this work, we present a facile and reproducible approach for the controllable synthesis of well-dispersed and monodispersed ZnO nanoparticles by using short-chain ethanolamine as the capping agent. It was found that ethanolamine plays an important role in the synthesis of monodispersed ZnO nanoparticles by controlling the nucleation and growth process. As a result, well-dispersed and size-controllable ZnO nanoparticles can be obtained. Compared with ligand-free conventional methods, our ligand-assisted approach has a higher reproducibility and a better controllability. We notice that QD-LEDs based on ligand-assisted ZnO exhibit a superior electroluminescence (EL) performance than those of traditional ZnO.