Nanocomposites of CdS Nanocrystals with Montmorillonite Functionalized with Thiourea Derivatives and Their Use in Photocatalysis
Nanocomposites of CdS Nanocrystals with Montmorillonite Functionalized with Thiourea Derivatives and Their Use in Photocatalysis
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DOI：
10.1021/jp3019556
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发表时间：
2012-10-18
影响因子：
3.7
通讯作者：
Gimenez, Iara F.
中科院分区：
文献类型：
--
作者：
Nascimento, Cristiane C.;Andrade, George R. S.;Gimenez, Iara F.
CdS的纳米复合材料的制备在DMF中使用的有机官能化的蒙脱土与硫脲衍生物，与不同比例的矩阵相对于镉离子。该基质提供了用于CdS形成的硫原子以及用于纳米晶体的系统锚定的特定结合位点。然而，为了得到立方CdS纳米晶体，需要向反应介质中加入硫脲，并且增加硫脲/Cd 2+摩尔比导致立方和六方CdS的混合物的形成。使用硫脲/Cd 2+的比例为2，立方CdS，得到的样品表现出光致发光由于直接复合和表面陷阱状态。CdS在整个基质中的分布的特征在于外表面上的纳米晶体（直径小于7 nm）的聚集体（直径在50 nm的区域中）以及夹层区域中的小柱的存在。在太阳光照射下降解罗丹明6 G的纳米复合材料的光催化性能进行了测试，在降解时间和矿化度方面有希望的结果。
Nanocomposites of CdS were prepared in refluxing DMF using a montmorillonite organofunctionalized with thiourea derivatives, with different proportions of the matrix relative to Cd2+ ions. The matrix provided sulfur atoms for CdS formation as well as specific binding sites for systematic anchoring of the nanocrystals. However, addition of thiourea to the reaction medium was required in order to yield cubic CdS nanocrystals, and increasing the thiourea/Cd2+ molar ratio led to the formation of mixtures of cubic and hexagonal CdS. The samples obtained using a thiourea/Cd2+ ratio of 2, with cubic CdS, exhibited photoluminescence due to both direct recombination and surface trap states. The distribution of CdS throughout the matrix was characterized by the presence of aggregates (with diameters in the region of 50 nm) of nanocrystals (with diameters less than 7 nm) on the outer surface as well as small pillars in the interlayer region. The photocatalytic performance of the nanocomposites was tested in the degradation of Rhodamine 6G under sunlight irradiation, with promising results in terms of degradation time and degree of mineralization.