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The present thesis is focused on the first step of nanostructured materials research -- the synthesis and characterization of nanomaterials. By designing novel systems and processes, we explored simple, mild and cheap methods to synthesize some important semiconductor nanomaterials. It is aimed at reducing the cost, minishing pollution, economizing energy and controlling the morphology and dimension of the obtained products. Meanwhile, many modern techniques including Powder X–ray diffraction (XRD), field emission scanning electron microscopy (FESEM), energy dispersive X-ray (EDX) spectra, Raman spectroscopy (Raman), Fourier transform infrared spectroscopy (FTIR) and UV–vis absorption spectra were used to characterize the as-synthesized products, and their possible formation mechanisms were also proposed. The main works completed are summed up as following:1. Hexagonal phase SnS2 nanoplates were synthesized by a novel low-temperature liquid-solid reaction method mainly via two simple steps: firstly, appropriate amounts of Sn, S and NH4Cl powders were mixed and ground thoroughly in a carnelian mortar, then transferred to a corundum crucible with a cover. The crucible containing the reactants was heated at 250℃for 0-10 h in an electric oven ( t = 0 h, that is to say, the heating of the reactants were stopped immediately when temperature reached 250℃), then allowed to cool to room temperature naturally; secondly, the resultant powders were washed with deionized water, filtered, dried in air at 50℃, and finally yellow SnS2 products were obtained. The phase, purity, morphology, size and optical property of the obtained products were characterized by XRD, Raman, EDX, FESEM, and UV-vis. 2. Hexagonal phase SnS2 nanoplates were synthesized via low-temperature molten salt method and liquid-solid reaction method by using SnCl2·2H2O as tin source and thiourea or sulfur finely dispersed as sulfur sources. Both of the proposed methods include two simple steps: firstly, appropriate amounts of SnCl2·2H2O and thiourea or S powders were mixed and ground thoroughly in a carnelian mortar, then transferred to a corundum crucible with a cover. The crucible containing the reactants was heated at 230-280℃for 0-10 h in an electric oven ( t = 0 h, that is to say, the heating of the reactants were stopped immediately when temperature reached 230-280℃), then allowed to cool to room temperature naturally; secondly, the resultant powders were washed with deionized water, carbon disulfide and ethanol, filtered, dried in air at 50℃, and finally yellow SnS2 products were obtained. The phase, purity, morphology, size and optical property of the obtained products were characterized by XRD, Raman, FESEM, and UV-vis.3. Nanostructured CuO microcrystallites with different morphologies were synthesized via two kinds of hydrothermal methods by using four copper sources (Cu(NO3)2·3H2O, CuCl2?2H2O, CuSO4?5H2O or Cu(CH3COO)2·H2O), H2O2, NH3?H2O as initial raw materials. The first one is one-step hydrothermal method, namely putting the copper sources (Cu(NO3)2·3H2O, CuCl2?2H2O, CuSO4?5H2O or Cu(CH3COO)2·H2O), H2O2 and NH3?H2O into a Teflon-lined stainless steel autoclave all together, sealed, and maintained at 70-150℃for 6-12 h. The as-formed CuO particles were filtered, washed with deionized water and ethanol, and finally dried in air at 50℃. The other one is two-step method: firstly, the CuOx?yH2O precursors were precipitated from the reaction of copper sources (Cu(NO3)2·3H2O, CuCl2?2H2O, CuSO4?5H2O or Cu(CH3COO)2·H2O), H2O2 and NH3?H2O in deionized water under the ambient condition; Then, monoclinic structure CuO could be obtained by hydrothermal treatment of the CuOx?yH2O precursors in deionized water at 70-100℃for 6-12 h. The phase, purity, morphology and size of the obtained products were characterized by XRD, FT-IR, FESEM and Raman, and their possible formation mechanisms were tentatively proposed.Finally, the conclusions and prospects of this thesis were given.
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