Nanoscale self-assembly in confined geometries

近年来，纳米材料的发展日新月异。这些新材料的一个例子是限制在纳米管中的富勒烯等纳米粒子，在这些系统中观察到了有序相。这种自序现象可能是它们独特的电学和光学性能的关键，这些特性目前正被用于生物医学应用和传感器技术。为了促进这些纳米材料的开发并实现其商业潜力，我们需要更好地了解它们的相行为。这项研究的主要目标是(I)加深对带电约束下纳米尺度自组装的基本了解，以及(Ii)探索这些系统的新应用，特别是在环境工程中。将使用蒙特卡罗和分子动力学模拟来研究(I)各种参数，如约束几何形状、颗粒大小和电荷不对称性对受限粒子结构性质的影响，以及(Ii)表面活性剂在约束下的自组装。此外，密度泛函理论将被应用于分析粒子间和粒子约束之间的相互作用。利用填砂柱研究胶束增溶有机物和表面活性剂在多孔介质中的吸附，并系统地研究了表面活性剂分子结构和溶液条件的影响。这项研究还将探索亚微米颗粒在有机污染物的固化/稳定中的应用。特别是，我们将通过测量污染物的浸出率来研究这些颗粒在水泥基质中作为有机物吸附剂的效果。这项研究的结果有望有助于我们对受限纳米颗粒和表面活性剂溶液的基本了解，特别是它们的自组装行为。更重要的是，对这些体系的增强知识将被证明对纳米材料的研究和开发有价值。此外，对受限纳米颗粒的研究也将有助于我们了解它们对环境的影响，这在最近几年已经成为一个越来越令人关注的问题。

The development of nanomaterials have been progressing rapidly in recent years. An example of these new materials consists of nanoparticles such as fullerene confined in a nanotube, and ordered phases have been observed in these systems.  Such self-ordering phenomena may be key to their unique electrical and optical properties, which are now being exploited in biomedical applications and sensor technologies.  To facilitate the development of these nanomaterials and to realize their commercial potential, we need a better knowledge of their phase behaviour. The primary objectives of this research are (i) to develop a fundamental understanding of nanoscale self-assembly in charged confinements, and (ii) to explore novel applications of these systems, particularly in environmental engineering.  Monte Carlo and molecular dynamics simulation will be used to study (i) the effects of various parameters, such as confinement geometry and particle size and charge asymmetry, on the structural properties of confined particles, and (ii) surfactant self-assembly in confinement.  In addition, density functional theory will be applied to analyze interparticle and particle-confinement interactions.  In the proposed experimental program, micellar solubilization of organics and surfactant adsorption in porous media will be studied using a sand-packed column, and a systematic study of the effects of surfactant molecular structure and solution conditions will also be conducted. This research will also explore the use of submicron particles in the solidification/stabilization of organic contaminants. In particular, we will study the efficacy of these particles as an organics adsorbent in cement matrices by measuring the contaminant leaching rate.  The results of this research are expected to contribute to our fundamental understanding of confined nanoparticles and surfactant solutions, particularly their self-assembling behaviour.  More importantly, the enhanced knowledge of these systems will prove to be valuable to nanomaterial research and development. In addition, the study of confined nanoparticles would also contribute to our knowledge of their environmental impact, which has become a growing concern in recent years.