[Spectroscopy study of aqueous CdTe quantum dots synthesized by microwave irradiation method]

Water-soluble CdTe nanocrystals capped with cysteamine were synthesized rapidly in aqueous solution by microwave irradiation with controllable temperature. Absorption and fluorescence spectra showed that these prepared CdTe quantum dots had good optical properties. The structure and diameter were characterized by the transmission electron microscopy (TEM) and X-ray powder diffraction (XRD). The effects of heating temperature, irradiation time and the concentrations of cysteamine on the growing velocity of CdTe QDs synthesized were also investigated. With the increase in the temperature and concentration of cysteamine, the nanoparticles grow faster, and for a longer reaction time, the maximum emission wavelength of the nanoparticles shows a red shift. Compared with the conventional aqueous synthesis, the microwave irradiation method showed some advantages such as the rapid velocity, good dispersibility and uniformity, narrow FWHM (full width at half maximum) and high quantum yield.