The structure and character of CdSe nanocrystals capped ZnO layer for phase transfer from hexane to ethanol solution

A new method for the preparation of CdSe/ZnO core-shell structure nanoparticles is described, where as-prepared CdSe nanocrystals in hexane were mixed with zinc acetate ethanol solution under ultrasonic. UV-visible absorption spectra, photoluminescence spectra and X-ray diffraction spectra were used to analyze the change of surface and structure of CdSe/ZnO core-shell nanocrystals by comparing with bare CdSe nanocrystals. The transmission electron microscopic images of CdSe/ZnO core-shell nanocrystals show that CdSe capped by ZnO is spherical or rod shape. The mechanism of the formation of CdSe/ZnO core-shell nanocrystals was discussed. During ZnO capping CdSe, the ligands of ZnO grown on the surface of CdSe nanocrystals provide a bridge for the CdSe nanocrystals transfer from hexane solution to ethanol solution. This experiment presents a simple, effective synthetic route for phase transfer of CdSe nanocrystals. (c) 2005 Elsevier B.V. All rights reserved.