Field Mediated Assembly of Anisotropic Colloids on Surfaces

该项目的目标是了解如何创建具有先进材料特性的不同形状颗粒的有序涂层。该项目旨在了解具有不同纵横比和曲率的不同形状的粒子如何相互作用，并动态地组装成具有有用特性的微结构。总体方法是使用光学显微镜实验和计算机模拟一起来测量和模拟粒子相互作用、动力学和组装过程。通过微电极施加的电场将被用来控制粒子如何集中，通过可调和定向吸引相互作用，并在避免无序状态的同时组装成有序的构型。该项目将为控制不同形状的胶体颗粒之间的相互作用和微结构的形成提供新的基本见解。这一认识将为设计组装具有新型电磁性能的表面涂层的工艺提供基础。该项目的其他好处包括培训未来的高级劳动力和扩大代表不足群体在当地学校的参与。为了实现这些目标，该项目将系统地提高各向异性胶体相互作用、微观结构和动力学的显微测量和分析模型的复杂性。在第一步中，目标是了解如何操纵单个和整体各向异性粒子的位置、方向和结构。这一目标将通过测量和建模各向异性粒子之间的电场中介相互作用来实现，以实现粒子形状的系统变化。下一步的目标是了解平衡相行为和非平衡微结构的形成对各向异性颗粒基材料性能的重要作用。这一目标将通过测量和建模不同的热力学条件和场中介相互作用如何控制微结构来实现。在第三步中，目的是了解各向异性粒子系统中朝向有序状态的动态路径如何决定目标微结构的处理。这一目标将通过测量和模拟相互作用和粒子形状如何决定集体动力学和缺陷弛豫作为浓度和构型的函数来实现。最后，将尝试扩大使用电极阵列的过程。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

The goal of this project is to understand how to create ordered coatings of different shaped particles with advanced material properties. The project aims to understand how different shaped particles, with different aspect ratios and curvature, interact with each other and dynamically assemble into microstructures with useful properties. The overall approach is to use optical microscopy experiments and computer simulations together to measure and model particle interactions, dynamics, and assembly processes. Electric fields applied through microelectrodes will be used to control how particles are concentrated, interact through tunable and directional attraction, and assemble into ordered configurations while avoiding disordered states. This project will provide new fundamental insights into the mechanisms governing the interactions among colloidal particles of different shape and the formation of microstructures. This understanding will provide a basis to engineer processes for assembling surface coatings with novel electromagnetic properties. Other benefits of the project include training a future advanced workforce and broadening participation of underrepresented groups in local schools. To achieve these goals, the project will systematically escalate complexity in microscopy measurements and analytical models of anisotropic colloidal interactions, microstructure, and dynamics. In the first step, the aim is to understand how to manipulate single and ensemble anisotropic particle position, orientation, and structure. This aim will be addressed by measuring and modeling electric field mediated interactions between anisotropic particles for systematic variations in particle shape. In the next step, the aim is to understand equilibrium phase behavior and non-equilibrium microstructure formation important to anisotropic particle based material properties. This aim will be attained by measuring and modeling how different thermodynamic conditions and field-mediated interactions control microstructures. In the third step, the aim is to understand how dynamic pathways towards ordered states in anisotropic particle systems determine processing of target microstructures. This aim will be achieved by measuring and modeling how interactions and particle shape determine collective dynamics and defect relaxation as functions as concentration and configuration. Finally, attempts will be made to scale-up processes using electrode arrays.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.