Studies on selective surface modification method and integration method for nanoparticles

纳米粒子的单层覆盖以进行适当的功能化，这可以极大地改变纳米粒子的物理和化学性质，是这些材料应用的关键因素。如果我们能够很容易地从纳米颗粒表面上的所需区域去除定量的有机化合物，然后在这些空区域涂覆其他化合物而不使纳米颗粒变形，我们就可以通过使用改性的颗粒来构建用于特殊应用的目标结构。在目前的工作中，二维组装的一半DODAC覆盖的Au纳米粒子获得的类朗缪尔技术，然后另一半的Au粒子的表面覆盖HFOTAI。用改性后的粒子将齐聚物制成各种溶剂。低聚物形成的重要因素是纳米粒子和溶剂之间的亲和力和烃链和/或氟碳链之间的相互作用。此外，DODAC覆盖的Au纳米颗粒通过UV/臭氧处理以制备半DODAC覆盖的颗粒。经处理的纳米颗粒的和频产生光谱表明Au纳米颗粒表面的中心对称结构的损失，即，受保护的表面活性剂分子的不对称分布。该结果表明，有机化合物的分解从纳米颗粒的上部开始。此外，所获得的半表面覆盖的Au纳米颗粒被用作低聚物结构的构建块。当Au纳米粒子在衬底上，在甲苯中进行超声处理，低聚物得到了60%的高产率。因此，发现将两种覆盖的有机化合物引入纳米颗粒表面对于制造纳米颗粒的低聚物结构是有用的。

Monolayer coverage of nanoparticles for appropriate functionalization, which can drastically change the physical and chemical properties of the nanoparticles, is a key factor in the application of these materials. If we are able to easily remove quantitative organic compounds from desired regions on a nanoparticles surface and then coat other compounds at these vacant regions without deformation of nanoparticles, we could construct target structures for special applications by the use of the modified particles. In the present work, 2D assembly of half DODAC-covered Au nanoparticles was obtained by the Langmuir-like technique, and then the other half-surface of Au particles was covered with HFOTAI. Oligomers were made into various solvents by using the modified particles. The important factor for oligomer formation was found to be the affinity between nanoparticles and solvents and the interaction between hydrocaobon chains and/or fluocarbon chains. Further, DODAC-covered Au nanoparticles were treated by UV/ozone to make half DODAC-covered particles. The sum frequency generation spectra of the treated nanoparticles indicated the loss of the centrosymmetric structure at the surface of Au nanoparticle, i.e., asymmetric distribution of protected surfactant molecule. This result shows that the decomposition of the organic compound starts from the upper part of the nanoparticles. Further, the half surfactant-covered Au nanoparticles obtained were employed as building blocks of oligomer structure. When the Au nanoparticles on a substrate were sonicated in toluene, oligomers were obtained in a high yield of 60%. Thus, it was found that the introduction of two covered-organic compounds to the nanoparticle surface is useful for fabricating the oligomer structures of nanoparticles.