The Preparation And Characterization Of CdS, ZnS And Zn_XCd_1-XS Nanomaterials

Nanosemiconductor particles have attracted broad attention from scientists in recent years. As importantⅡB-ⅥA semiconductor nanometerials, CdS and ZnS exhibit unique physical and chemical properties that can not be obtained in their bulk corresponding counterpas. They have potential application in many areas. So the investigation for the synthesis ways to nanosemiconductor particles becomes a very active topic home and overseas.In this paper, CdS, ZnS nanosemiconductors and composite ZnXCd1-XS nanoparticles were obtained successfully through a facile and inexpensive chemical synthesis scheme in solutions respectively. The organic regent ethanol was used as reaction medium, acetic cadmium (0.002mol·L-1), acetic zinc (0.002mol·L-1) and thiourea (0.004mol·L-1) were the reaction precursors, different concentration of Polyvinylpyrrolidone was the macromolecular surfactant. The whole reaction system keep the temperature of ethanol circumfluence under strongly continuous magnetic stirring, a few minutes latter, CdS and ZnS semiconductor particles were obtained respectively. The composite ZnXCd1-XS nanoparticles were also prepared via changing the molar ratios of acetic cadmium and acetic zinc in this mixed ternary. Keep the consistent conditions with the front all the same, foregoing three kinds nanoparticles were gained in the reaction system of N,N-Dimethylformamide(DMF) at 100℃.UV-Vis absorption spectrum, Transmission electron mirror images, Fluorescence spectra and X-ray diffraction patterns were used to characterize optical properties and crystalloid structures of samples. The UV-Vis absorption spectrum of samples was analyzed. Their spectrums shift evidently to short wavelength. This is so called the phenomenon of blue-shift due to quantum size effect. The transmission electron mirror images showed that the size of particles was the range of 25～60nm. The dispersibility and stability of them were good in ethanol and DMF. Besides, their photoluminescence spectrum was measured. The results indicated CdS and ZnS semiconductor nanoparticals brought obvious surface trap irradiance. Lots of color-tunable emission of the composite ZnXCd1-XS nanoparticles could be watched by changing the composition of particles. X-ray diffraction patterns of nanosemiconductor CdS was obtained and indicated that it was cubic crystalloid.