Abstract
The luminescent properties of undoped ZnO quantum dots encapsulated in various stabilizing agents have been investigated at room temperature. Stoichiometric as well as non-stochiometric ZnO quantum dots have been prepared by different routes. These studies indicate the importance of OH radical on the surface of ZnO quantum dots. In general, it has been observed that surface defects play an active role in the luminescence behaviour of quantum dots. ZnO quantum dots, doped with copper, have also been studied. Doping Cu in ZnO quantum dots, which have OH radical on its surface, is responsible for quenching green luminescence at 530 nm.