NSF-DFG Confine: Building functional supraparticles through directed assembly of nonspherical nanoparticles under confinement

结晶是一种普遍现象，是许多自然和合成过程的基础。例如雪花的生长，蛋白质结构的解决，以及药物的发现。与在无限空间中对结晶进行广泛的实验研究不同，在有限几何空间中对结晶的研究较少，但研究内容丰富，对细胞聚集体的生长、生物模式的形成、病毒衣壳内DNA的包装、光电子学和高效食品包装运输等现象具有深远的影响。纳米粒子（NPs）在约束条件下（例如，在乳状液滴中）的胶体结晶产生了明确的和可分散的超结构，即所谓的超粒子。本提案的首要目标是通过利用限制几何来直接NP组装和结晶来推进超粒子的设计和合成。与广泛的计算和实验研究不同，我们的超粒子将由数万个形状各向异性的NPs组成。我们的中心假设是NP形状，表面化学和约束环境的影响的相互作用将解锁具有精确三维排列的丰富多样性的超粒子。我们位于美国和德国的实验计算团队将研究NP特性（大小、形状、组成和配体化学）和约束条件（约束的维度和曲率）的影响，以揭示控制超粒子组装途径和相行为的原理。我们的工作将扩展超粒子设计的工具箱，并将通过结合现实的粒子间相互作用来刺激未来超越硬多面体的计算研究。所获得的超粒子在等离子体超材料、多孔材料、可回收催化剂、药物输送、化妆品、制药和食品科学等领域有很好的应用前景。我们的长期目标是创建具有定制属性和最大性能的分层有序，应用就绪的超粒子。

Crystallization is a universal phenomenon that underpins many natural and synthetic processes. Examples are the growth of snowflakes, solving the structure of proteins, and pharmaceutical drug discovery. Unlike the extensive experimental studies on crystallization in infinite space, crystallization in a confining geometry is a less explored, yet rich research topic with profound implications in phenomena as diverse as the growth of cellular aggregates, biological pattern formation, DNA packaging inside virus capsids, optoelectronics and efficient food packaging and transport. Colloidal crystallization of nanoparticles (NPs) under confinement (e.g., in emulsion droplets) creates defined and dispersible superstructures, so-called supraparticles. The over-arching objective of this proposal is to advance the design and synthesis of supraparticles by leveraging confined geometries to direct NP assembly and crystallization. Distinct from extensive computational and experimental studies on spherical NPs under confinement, our supraparticles will consist of tens to thousands of shape-anisotropic NPs. Our central hypothesis is that the in-terplay of NP shape, surface chemistry, and the influence of the confinement environment will unlock a rich diversity of supraparticles with precise three-dimensional arrangements. Our ex-perimental-computational team located in the USA and Germany will study the effects of NP characteristics (size, shape, composition, and ligand chemistries) and confinement conditions (dimensionality and curvature of confinement) to uncover the principles governing assembly pathways and phase behaviors of supraparticles. Our work will expand the toolbox of supra-particle-by-design and will stimulate future computational studies that go beyond hard polyhedra by incorporating realistic interparticle interactions. The supraparticles obtained are promising candidates for applications in plasmonic metamaterials, porous materials, recyclable catalysts, drug delivery, cosmetics, pharmaceutical and food sciences, among others. Our long-term goal is to create hierarchically ordered, application-ready supraparticles with tailored properties and maximum performance.