CdS纳米结构的水相可控合成及表征

Aqueous Shape-Controlled Synthesis and Characterization of CdS Nanostructures

摘要: 以醋酸镉和硫代乙酰胺为原料，在水溶液中于温和的温度下完成了硫化镉纳米晶的形貌可控合成。利用表面活性剂辅助调控合成了硫化镉纳米球复合结构和纳米棒状结构，透射电镜分析表明硫化镉纳米棒实际上是由粒径更小的纳米单元按照取向生长机理沿一维方向组装而成，而球形纳米结构是硫化镉纳米粒子的球形集合体。我们认为聚乙二醇的长链模板效应有助于一维纳米结构的形成，而十二烷基苯磺酸阴离子形成的球形胶束诱导了硫化镉的纳米球形团簇的形成。紫外可见吸收谱分析表明合成的硫化镉样品具有强的紫外吸收。本文的合成方法为硫化镉纳米晶材料提供了一条经济可行的合成路线，同时也会为其他半导体纳米材料开辟一条新的制备途径。

Abstract: Cadmium sulfide microcrystallines with tuning morphologies were prepared with cadmium acetate and thio-acetamide as raw materials by aqueous process under mild temperature. The sphere-like hierarchical and rod-shaped cadmium sulfide nanostructures can be modulated by employing different surfactants. The transmission electron mi-croscopy resolutions indicated that the nanorods actually are one-dimensional assemblies of smaller cadmium sulfide nanounits abiding the oriented assembly mechanism, but the cadmium sulfide spheres are the random aggregations of cadmium sulfide nanograins. We propose that the linear templating effect of surfactant PEG-400 contributes to the rod-like assembly of cadmium sulfide nanounits, while the spherical micelles of anion dodecylbenzenesulfonate induce the spherical aggregation of cadmium sulfide grains. The ultraviolet-visible absorption spectra show that the cadmium sulfide samples all had strong absorption in ultraviolet region with obvious blue shifts. The method provides economi-cally feasible route for controlled synthesis of cadmium sulfide nanocrystals, and may open a new avenue to fabricate other semiconductor nanocrystals.