CdS nanoclusters were synthesized by using n-octylthiol as a ligand and n-hexadecyltrimethyl-ammonium bromide (or n-tetrabutylammonium bromide) as an organic cation. Sizeselective precipitation techniques have enabled...CdS nanoclusters were synthesized by using n-octylthiol as a ligand and n-hexadecyltrimethyl-ammonium bromide (or n-tetrabutylammonium bromide) as an organic cation. Sizeselective precipitation techniques have enabled the preparation of different CdS Q-nanoparticles with narrow size distribution and mean diameters ranging from 2 to 5 nm. UV-Vis spectroscopy, transmission electron microscopy and small-angle X-ray scattering were used to determine the mean cluster size. Their size quantization effect has been observed in UV-Vis spectra, fluorescence spectra and small-angle X-ray diffraction, but it became too weak to be observed for large particles (2r > 10 nm). Moreover, their photo-catalysis has been studied by ESR technique and the results revealed that the photo-catalytic reaction occurred in the solution system and some free radicals such as CH2-OH in methanol, or CH3-CH-OH in ethanol were generated if some CdS Q-particles were added to methanol (or ethanol) and initiated by UV light at the same time, which may be very crucial in organic synthesis.展开更多
文摘CdS nanoclusters were synthesized by using n-octylthiol as a ligand and n-hexadecyltrimethyl-ammonium bromide (or n-tetrabutylammonium bromide) as an organic cation. Sizeselective precipitation techniques have enabled the preparation of different CdS Q-nanoparticles with narrow size distribution and mean diameters ranging from 2 to 5 nm. UV-Vis spectroscopy, transmission electron microscopy and small-angle X-ray scattering were used to determine the mean cluster size. Their size quantization effect has been observed in UV-Vis spectra, fluorescence spectra and small-angle X-ray diffraction, but it became too weak to be observed for large particles (2r > 10 nm). Moreover, their photo-catalysis has been studied by ESR technique and the results revealed that the photo-catalytic reaction occurred in the solution system and some free radicals such as CH2-OH in methanol, or CH3-CH-OH in ethanol were generated if some CdS Q-particles were added to methanol (or ethanol) and initiated by UV light at the same time, which may be very crucial in organic synthesis.
