摘要：目前纳米质料的钻研与研发均获得了长足的发展，并已被广泛应用在生物、化工、电子等多个领域中。而金纳米粒子在传感、检测、器件及生物医学等领域中的应用尤为普遍，这是由于其特有的力、热、光、表面等离子体等性质。虽然已有很多研究工作者对金纳米粒子的合成、表征和应用进行过广泛地研究，但是运用表面覆盖剂对于金纳米粒子的可控合成及精确控制仍是很有意义的话题。控制尺寸的能力对于纳米材料的电子、光学和磁特性的开发来说是必不可少的。可控的生长法为在合成和处理纳米粒子的过程中控制其尺寸、形状和组成提供了一个重要的途径。本课题将描述在用硫醇单层覆盖的预成型小尺寸金纳米颗粒的聚集生长中，覆盖分子所起到的作用的研究结果。而较大粒径的金纳米颗粒则通过硫醇单分子膜在粒子表面的组装从而实现粒径的高度单分散性。实验中制备了2 nm金纳米种子，并通过热活化让种子聚集生长成3.7 nm至7.8 nm之间不同粒径大小的金纳米粒子。结果表明，溶液中覆盖剂的浓度决定了尺寸的可控性。在0.21 M至0.34 M的硫醇浓度范围内，溶液中硫醇浓度每增多0.01 M，那么产生的金纳米粒子的核心粒径就会减小约0.27 nm。硫醇与四辛基溴化铵的比率也在一定程度上影响了粒子的大小与稳定性。研究过程中观察到不同浓度的烷硫醇溶液在吸附等温线上的转变。通过表面表征手段确定纳米粒子的最终尺寸，从而在覆盖剂的浓度与粒子尺寸二者之间建立了相关性，为纳米粒子大小的精确控制以及尺寸的单分散性等方面提供重要的指导意义。

关键词： 金纳米粒子；表面覆盖剂；可控合成

Surface coverings used in the study of controlled synthesis of nanoparticles

Abstract： At present, nano-materials research obtained rapid development, has been widely used in biological, chemical, electronics, and other different fields. Among them, gold nanoparticles have a wide application in sensing, detection, device and biomedicine, with their unique properties of power, heat, light and surface plasmas. Although the synthesis, characterization and application of gold nanoparticles have been extensively studied by many researchers, it is still a significant topic to apply surface coating agents to the controllable synthesis and precise control of gold nanoparticles. The ability to control dimensions is indispensable for the development of nanomaterials’ electronic, optical and magnetic properties.  The controlled growth method provides an important way to control the size, shape and composition of the nanoparticles during their synthesis and processing. This report will describe the results of the study on the role of the capping molecules in the aggregation growth of the preformed small size gold nanoparticles capped with alkanethiolate monolayers toward monodispersed larger sizes. The larger particle size gold nanoparticles are assembled on the surface of the particles through a thiol monolayer to achieve a highly monodisperse particle size. In the experiment, 2 nm gold nano seeds were prepared and the seeds were aggregated and grown into gold nanoparticles with different particle sizes ranging from 3.7 nm to 7.8 nm by thermal activation. The experimental results show that the concentration of the covering agent in the solution determines the controllability of the size. In the mercaptan concentration range of 0.21 M to 0.34 M, the concentration of thiol in the solution increases by 0.01 M, and the resulting gold nanoparticles have a core particle size reduction of about 0.27 nm. The ratio of thiol to tetraoctylammonium bromide also affects the particle size and stability to some extent. During the study, different concentrations of alkanethiol solutions were observed on the adsorption isotherms. The final size of the nanoparticles is determined by means of surface characterization, thereby establishing a correlation between the concentration of the covering agent and the particle size, which provides important guiding significance for the precise control of the size of the nanoparticles and the monodisperseness of the size. 表面覆盖剂用于可控合成纳米粒子的研究:http://www.chuibin.com/huaxue/lunwen_205858.html