Synthesis of CdS nanocrystals based on low-temperature thermolysis of one single-source organometallic precursor

Abstract

CdS nanocrystals have been synthesized based on low-temperature thermolysis of one single-source organometallic precursor in noncoordinating (ethanol) or coordinating (oleic acid) solvent. The organometallic precursor was prepared by using cadmium chloride, thiourea and sodium hydroxide in ethanol solution. The products were characterized by high-resolution transmission electron microscopy (HRTEM) and x-ray powder diffraction (XRD). The nucleation and growth stage were investigated by ultraviolet–visible (UV–vis) absorption spectroscopy. CdS nanocrystals prepared in oleic acid have a narrower size distribution than those prepared in ethanol. Phase transformation of CdS nanocrystals from a cubic to hexagonal structure in ethanol solution during the ageing stage was observed. Strong photoluminescence was observed in CdS nanocrystals prepared in oleic acid.