Thiol-terminated Di-, Tri-, and tetraethylene oxide functionalized gold nanoparticles: A water-soluble, charge-neutral cluster
Thiol-terminated Di-, Tri-, and tetraethylene oxide functionalized gold nanoparticles: A water-soluble, charge-neutral cluster
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DOI：
10.1021/cm020007a
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发表时间：
2002-05-01
影响因子：
8.6
通讯作者：
Ancona, MG
中科院分区：
文献类型：
--
作者：
Foos, EE;Snow, AW;Ancona, MG
制备了一系列固定长度短环氧乙烷低聚体稳定的金纳米团簇，并对其进行了表征。通过巯基交换反应将巯基CH3(OCH2CH2)(n)SH（其中n = 2,3和4）取代到1.8 nm的己硫醇包覆金簇表面，并通过NMR， FTIR和UV/vis光谱对所得到的纳米簇进行了表征；TGA;和TEM分析。配体交换度大于99%，最终材料中的金芯直径保持不变。特别有趣的是，n = 2的簇是不溶于水的，而n = 3或4的簇是水溶性的。这些簇的薄膜电导率与链长相似的烷硫醇覆盖簇的薄膜电导率进行了比较，发现大约要大1个数量级。在化学蒸汽传感器结构中，这一系列的簇显示出强烈的电响应，这表明环氧乙烷配体的长度与蒸汽的极性之间存在相关性。
A series of gold nanoclusters stabilized by ligands containing short ethylene oxide oligomers of fixed length were prepared and characterized. The thiols CH3(OCH2CH2)(n)SH (where n = 2, 3, and 4) were substituted onto the surface of 1.8-nm hexanethiol-capped gold clusters by a thiol-exchange reaction, and the resulting nanoclusters were characterized by NMR, FTIR, and UV/vis spectroscopies; TGA; and TEM analysis. A degree of ligand exchange greater than 99% was achieved, and the gold core diameter remained unchanged in the final material. Of particular interest, the cluster with n = 2 was water-insoluble, whereas those with n = 3 or 4 were water-soluble. The thin-film electrical conductivities of these clusters were compared with those of alkanethiol-capped clusters of similar chain lengths and found to be roughly 1 order of magnitude greater. In a chemical vapor sensor configuration, this series of clusters displayed strong electrical responses that showed a correlation between the length of the ethylene oxide ligand and the polarity of the vapor.