Study on effects of sodium hydroxide on synthesis of zinc telluride nanocrystals by hydrothermal method

Zinc telluride nanocrystals were synthesized in sodium hydroxide solution by the hydrothermal method using zinc and tellurium powders. The zinc telluride nanocrystals were analyzed by X-ray diffractometry, transmission electron microscopy and micro-Raman spectroscopy. The X-ray diffraction patterns indicate that zinc telluride crystallizes in zincblende structure and the residual impurities change with the content of sodium hydroxide. The images of transmission electron microscopy show that the size of zinc telluride nanocrystals varies with the content of sodium hydroxide. The Raman spectra exhibit a series of longitudinal optical multiphonon peaks up to the fourth order peak. Employing theory related to crystal growth and resonance Raman scattering, growth of zinc telluride nanocrystals was studied and their band gaps were estimated. These results lead to further insights into controlling the synthesis of zinc telluride nanocrystals and correlation with their electronic structure. (c) 2011 Elsevier Ltd. All rights reserved.