Colloidal membranes and assembly of heterogeneous 2D materials

非技术性：两亲性分子由亲水组分和亲油组分组成，这些组分彼此永久相连，因此阻碍了批量分离。当这些分子加入水中时，它们会自组装成薄膜，这些薄膜具有显著的特性，在生物学、物理学和材料科学中发挥着至关重要的作用。通常认为，两亲性分子的对抗性是膜组装的基本要求。在这项建议中，PI将研究一种完全不同的胶体基膜状材料的组装方法。这种新型胶体膜的组装是在化学上均一的丝状病毒和聚合物的简单混合物中进行的，丝状病毒具有台球球杆的形状，聚合物类似台球。除了提供对所有膜状材料通用方面的基本见解外，结果还将描述一种新的、可轻松扩展的过程，将棒状纳米颗粒组装成可用作高效光伏设备的新型纳米结构。PI的研究和教育计划通过相互强调可视化技术和跨学科的科学方法无缝地结合在一起。具体地说，国际和平研究所将继续与行动中的发现博物馆建立现有的成功合作关系，以便组织一年两次的博物馆参观，亲身演示光学显微镜和材料科学的各种概念。PI还将通过参加科学博览会、组织班级访问和在他的实验室接待学生来扩大与当地中小学的联系。最后，PI将继续为本科生提供从事研究项目的机会，并将继续建立现有的本地和全国联系，以招收在STEM领域中代表性不足的学生团体。技术：胶体膜是由一棒长的厚液体状排列的棒组成的单分子层，通过包裹聚合物溶液的渗透压力将其结合在一起。这项建议的目的是阐明胶体膜组装过程的基本规律，并将胶体膜作为设计新一代空间非均质、形状变化的功能材料的基础。PI将首先使用胶体膜作为一个强大的平台，用于组装定义良好的介观簇和具有预定异质性的宏观2D材料。同时，PI将设计新的方法来测量胶体膜的机械性能，并利用这一知识来设计形状变化的3D材料。胶体膜本身就很有趣，因为它们提供了在微米尺度上组织复杂2D材料的独特机会。此外，尽管在分子尺度上不同，但胶体单层和脂双层的连续变形可以用相同的自由能表达式来描述。因此，它们提供了一个独特的机会来深入了解普遍的膜过程，这些过程主要由系统的基本对称性决定。

Non-technical: Amphiphilic molecules consist of water loving and oil loving components that are permanently linked to each other, thus frustrating bulk separation. When added to water these molecules self-assemble into membranes, thin flexible sheets with remarkable properties that play an essential role in biology, physics, and material science. It is commonly believed that the antagonistic nature of the amphiphilic molecules is an essential requirement for membrane assembly. In this proposal PI will study a fundamentally different method for assembly of colloidal based membrane-like materials. Assembly of the novel colloidal membranes takes place in a simple mixture of chemically homogeneous filamentous viruses, which have the shape of billiard cues, and polymers, which resemble billiard balls. Besides providing fundamental insight into universal aspects of all membrane-like materials, results will also describe a new and easily scalable process for assembly of rod-like nanoparticles into novel nanostructures that could act as efficient photovoltaic devices. The PI's research and education plans are seamlessly joined together through their mutual emphasis on visualization techniques and an interdisciplinary approach to science. Specifically, the PI will continue to build upon existing successful collaborations with The Discovery Museum in Action, in order to organize biannual visits to the museum for hands-on demonstrations of various concepts in optical microscopy and materials science. The PI will also extend connections with the local elementary and middle schools by participating in Science Fairs, by organizing class visits, and hosting students in his laboratory. Finally, the PI will continue to provide opportunities to undergraduate students to pursue research projects and will continue to build upon existing local and national connections in order to recruit students form groups that are underrepresented in STEM fields.Technical: Colloidal membranes are comprised from a one-rod-length thick liquid-like monolayer of aligned rods that is held together by the osmotic pressure of the enveloping polymer solution. The goal of this proposal is to elucidate the fundamental laws that govern the assembly processes of colloidal membranes and to use colloidal membranes as a basis for engineering of a new generation of spatially heterogeneous, shape-changing functional materials. The PI will first use colloidal membranes as a robust platform for assembly of well-defined mesoscopic clusters and macroscopic 2D materials with predetermined heterogeneities. In parallel, the PI will devise new methods to measure the mechanical properties of colloidal membranes, and use this knowledge to engineer shape-changing 3D materials. Colloidal membranes are interesting in their own right as they offer a unique opportunity to organize complex 2D materials on micron scales. Furthermore, although distinct on molecular scales, the continuum deformations of colloidal monolayers and lipid bilayers are described by the same free energy expressions. Thus they provide a unique opportunity to gain insight into universal membrane processes that are mainly determined by the fundamental symmetries of the system.