Patchy Colloids & Colloidal Molecules

斑状胶体

• 批准号: 0706453
• 负责人: David Pine
• 金额: $ 36万
• 依托单位: New York University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-09-01 至 2010-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0706453&HistoricalAwards=false
• 关键词: Patchy; Colloids; & Colloidal; Molecules

Non-Technical Abstract: This project addresses a central goal of contemporary materials science: to create methods for manipulating and assembling materials on the nanoscale. While chemists address such problems on a molecular scale, methods for designing and assembling small molecular aggregates known as "nanoparticles" or "colloids" are poorly developed. Such particles, 100 to 100,000 times smaller than the diameter of a human hair, are usually spherical with surfaces that either uniformly repel or stick to each other where they first happen to touch. However, to design organized useful structures, particles cannot simply stick where they first touch but need to have "hands" that grab onto each other only at specific points on their surfaces and only along certain directions. The goal of this project is to use newly developed nanoparticles that have sticky pads or "hands" arranged in such a way that the particles assemble into structures that have technologically useful optical, electrical, and mechanical properties. The research could lead to new materials for manipulating light, which could be used in optical circuits for enhanced communications and computing. This project, jointly funded by DMR and CBET, also provides a rich multifaceted training for students in the increasingly technologically important areas of colloidal and nanoparticle self assembly and photonic materials. Technical Abstract:The goal of this project is to develop and study self assembly of two new classes of non-spherical colloidal particles: "patchy colloids" and "colloidal molecules." Patchy colloids are nearly spherical particles having highly symmetric directional interactions, for example colloidal spheres with four attractive pads arranged with tetrahedral symmetry on the particle surface. Colloidal molecules are high-symmetry clusters made from colloidal spheres irreversibly linked together. These include dumbbells, triangles, tetrahedra, and octahedra, as well as more exotic clusters. The fundamental motivation is to understand the role of particle shape and directional interactions for self assembly at the micron scale and below. A long-term practical motivation is to develop colloidal crystals that are useful for making complex colloidal crystals and other structures such as photonic band gap crystals. Questions to be addressed include: (1) How can directionality, strength, range, and specificity of interparticle interactions be manipulated to create new colloidal structures? (2) How do particle shapes with lower symmetry than spherical change the phase diagram of condensed phases? (3) What is the effect of external fields on particles of reduced symmetry and how can they be used to manipulate and control the self assembly and structure of these new colloids? This project, jointly funded by DMR and CBET, also provides a rich multifaceted training for students in the increasingly technologically important areas of colloidal and nanoparticle self assembly and photonic materials.

非技术摘要：该项目解决了当代材料科学的一个中心目标：创建在纳米尺度上操纵和组装材料的方法。 虽然化学家在分子尺度上解决了这些问题，但设计和组装被称为“纳米颗粒”或“胶体”的小分子聚集体的方法还很薄弱。 这些颗粒的直径比人类头发的直径小 100 到 100,000 倍，通常是球形的，其表面在它们第一次接触时要么均匀地排斥，要么相互粘附。然而，为了设计有组织的有用结构，粒子不能简单地粘在它们第一次接触的地方，而是需要有“手”，仅在其表面的特定点并且仅沿着某些方向相互抓住。该项目的目标是使用新开发的纳米粒子，这些纳米粒子具有粘性垫或“手”，其排列方式使粒子组装成具有技术上有用的光学、电学和机械特性的结构。 这项研究可能会产生用于操纵光的新材料，这些材料可用于光电路中以增强通信和计算。该项目由 DMR 和 CBET 共同资助，还在胶体和纳米粒子自组装以及光子材料等技术日益重要的领域为学生提供丰富的多方面培训。技术摘要：该项目的目标是开发和研究两类新的非球形胶体颗粒的自组装：“斑状胶体”和“胶体分子”。片状胶体是具有高度对称方向相互作用的近球形颗粒，例如在颗粒表面上具有以四面体对称排列的四个吸引垫的胶体球。胶体分子是由不可逆地连接在一起的胶体球组成的高度对称的簇。 其中包括哑铃形、三角形、四面体和八面体，以及更奇特的簇。根本动机是了解颗粒形状和定向相互作用对于微米级及以下自组装的作用。长期的实际动机是开发可用于制造复杂胶体晶体和其他结构（例如光子带隙晶体）的胶体晶体。需要解决的问题包括：（1）如何操纵颗粒间相互作用的方向性、强度、范围和特异性来创建新的胶体结构？ (2) 对称性低于球形的颗粒形状如何改变凝聚相的相图？ (3) 外部场对对称性降低的粒子有何影响？如何利用外部场来操纵和控制这些新胶体的自组装和结构？ 该项目由 DMR 和 CBET 共同资助，还在胶体和纳米粒子自组装以及光子材料等技术日益重要的领域为学生提供丰富的多方面培训。