Nanomanufacturing of Hierarchical Colloidal Nanomaterials Using Multi-scale Interactions

一个重要的纳米制造挑战是开发快速和连续的制造方案，以控制材料结构，从单个纳米粒子的尺寸(纳米)，到组装的微结构(微米)，到感兴趣的电磁波长(微米到米)量级的设备特征。这种多尺度材料在自然界中经常被观察到，在蝴蝶和甲虫翅膀内的光子建筑中，或者在木材、丝绸和海贝壳中的常见机械元件中。不幸的是，创造大规模材料的合成方法仍然缺乏，这些材料既包括自然材料的复杂性，也包括自然材料中的分层特征。该奖项的目的是为创造一种制造多尺度胶体纳米材料的方法发展必要的基本理解。该项目将在运输、组装和聚合等关键科学和技术领域取得进展。生产胶体纳米材料的组装工艺的开发对任何旨在操纵电磁辐射的应用都很有用，例如传感器和太阳能电池，以及更具新奇色彩的新兴应用，如光学计算和光学隐身。外展工作包括让高中生和本科生参与实验室工作。参与该项目的学生将被鼓励出席会议，并参与当地小学的额外外展工作。分级胶体材料纳米制造项目基于将强相互作用和弱相互作用结合起来，以实现一种在大范围内连续组装纳米颗粒结构的加工方法。这种方法依赖于耦合流体动力学和毛细管相互作用来快速传输和组织预定义图案表面上的纳米颗粒液滴，通过场中介相互作用平衡整体对流和局部扩散介导的纳米颗粒微结构组装，并通过可聚合介质快速阻止或固定结构以冷却纳米颗粒构型。单独而言，现有技术可以满足这些步骤，但将它们结合在一起会带来重大的工程和科学挑战。例如，有必要协调与扩散、毛细和流体动力传输相关的不同的时间和长度尺度，以便能够在单一步骤中形成多尺度结构。考虑到这些过程运行的尺度之间不完全分离，理解如何在它们竞争和/或耦合的制度下控制相互作用，将通过光学显微镜和模拟完成。

An important nanomanufacturing challenge is to develop rapid and continuous manufacturing schemes to control material structures from the dimensions of individual nanoparticles (nanometers), to assembled microstructures (micrometers), to device features on the order of the electromagnetic wavelengths of interest (micrometer to meters). Such multi-scale materials are routinely observed in nature in photonic architectures within butterfly and beetle wings, or in common mechanical elements within wood, silk, and sea shells. Unfortunately, synthetic approaches to create large scale materials that encompass both the complexity and hierarchical features found in natural materials are still lacking. The objective of this award is to develop the fundamental understanding necessary for the creation of a method to fabricate multiscale colloidal nanomaterials. The project will result in advancements in critical scientific and technological areas such as transport, assembly and polymerization. The development of assembly processes to produce colloidal nanomaterials is useful for any application that aims to manipulate electromagnetic radiation, for example, sensors and solar cells, and more exotic emerging applications like optical computing and optical cloaking. Outreach efforts include engagement and participation of high school and undergraduate students in the laboratory. Students participating in the project will be encouraged to present at conferences and be involved with additional outreach efforts at local elementary schools.The hierarchical colloidal materials nanomanufacturing project is based on combining strong and weak interactions towards a processing method that continuously assembles nanoparticle structures over a large area. This approach relies on coupling hydrodynamics and capillary interactions for rapid transport and organization of nanoparticle-loaded droplets on predefined patterned surfaces, balancing bulk convection and local diffusion-mediated assembly of nanoparticle microstructures via field-mediated interactions, and rapidly arresting or immobilizing structures through polymerizable media to quench nanoparticle configurations. Individually, these steps can be met with existing technologies, but combining them brings significant engineering and scientific challenges. For example, it is necessary to orchestrate the disparate time- and length-scales associated with diffusive, capillary, and hydrodynamic transport to enable multiscale structure formation in a single step. Given the imperfect separation between the scales at which these processes operate, understanding of how to control interactions in regimes where they compete and/or are coupled will be accomplished via optical microscopy, and simulations.