NSF-DFG Confine: Drying-induced assembly of colloidal supraparticles from anisotropic nanoparticles

NSF-DFG Confine：干燥诱导各向异性纳米粒子组装胶体超粒子

• 批准号: 2223084
• 负责人: Michael Howard
• 金额: $ 27.14万
• 依托单位: Auburn University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-15 至 2025-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2223084&HistoricalAwards=false
• 关键词: NSF; DFG; Confine; Drying; induced

This project was awarded through the “Chemistry and Transport in Confined Spaces (NSF-DFG Confine)" opportunity, a collaborative solicitation that involves the National Science Foundation and Deutsche Forschungsgemeinschaft (DFG). Colloidal supraparticles - micrometer-sized spheres made from smaller nanoparticles (NPs) - are versatile materials. Porous supraparticles with internal voids are particularly valued for their catalytic, photonic, drug delivery, and physical absorption properties. While supraparticles can be fabricated at scale using solvent drying to assemble NPs inside liquid droplets, these processes are poorly understood. This project will use computer modeling to address this knowledge gap in how porous supraparticles form and how their properties can be engineered. Furthermore, the nanoparticle shape and surface property effects on the assembly process and the characteristics of the product supraparticles will be investigated. The models that will be developed have significant potential to shorten the research & development cycle of new materials in both academic and industrial settings. This international collaboration will train a globally competitive work force. The project will also integrate activities to (1) broaden participation in computational science through a summer research experience for undergraduates underrepresented in STEM, (2) develop a virtual-reality educational activity on diffusion for K-12 students, and (3) disseminate open-source software and training materials.The goal of this project is to develop mathematical models to investigate the drying-induced assembly of nanoparticles (NPs) with interaction or shape anisotropy into colloidal supraparticles. This process is poorly understood because it involves complex molecular thermodynamics and nonequilibrium transport in confinement. Complementary particle-based and continuum models - based on the multiparticle collision dynamics and classical dynamic density functional theory approaches, respectively - will be developed and validated. The models will be applied to “patchy” NPs with anisotropic attraction and rodlike NPs with anisotropic shape that have significant untapped potential for realizing new porous supraparticle assemblies. The local NP density and orientational order will be characterized to systematically interrogate how both the NP properties and the processing conditions (such as the drying speed) determine the porosity distribution in the supraparticle. The proposed research will not only improve our ability to engineer supraparticles but also advance fundamental understanding of confined advection-diffusion processes for NPs, including related processes such as freeze drying, filtration, and sedimentation.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.

该项目是通过“密闭空间的化学与运输（NSF-DFG Confine）”机会获得的，这是一项涉及美国国家科学基金会和德国研究协会（DFG）的合作招标项目——胶体超粒子——由较小纳米颗粒制成的微米级球体（ NPs） - 具有内部空隙的多孔超颗粒因其催化、光子、药物输送和物理特性而特别有价值。虽然可以使用溶剂干燥在液滴内组装纳米粒子来大规模制造超粒子，但该项目将使用计算机建模来解决多孔超粒子如何形成以及如何设计其特性的知识空白。此外，还将研究纳米粒子的形状和表面性质对组装过程以及产品超粒子特性的影响，所开发的模型对于缩短学术和工业新材料的研发周期具有巨大潜力。这项国际合作将培训一支具有全球竞争力的劳动力，以 (1) 通过为 STEM 领域代表性不足的本科生提供暑期研究经验，扩大对计算科学的参与，(2) 开展虚拟现实教育活动。为 K-12 学生进行扩散，(3) 传播开源软件和培训材料。该项目的目标是开发数学模型来研究干燥诱导的具有相互作用或形状各向异性的纳米颗粒 (NP) 组装成人们对该过程知之甚少，因为它涉及复杂的分子热力学和约束中的非平衡传输，将分别基于多粒子碰撞动力学和经典动态密度泛函方法理论来开发和验证。该模型将应用于具有各向异性吸引力的“片状”纳米粒子和具有各向异性形状的棒状纳米粒子，它们在实现新型多孔超粒子方面具有巨大的未开发潜力局部纳米颗粒密度和取向顺序将被表征，以系统地询问纳米颗粒特性和加工条件（例如干燥速度）如何决定超颗粒中的孔隙率分布。超粒子，而且还促进了对纳米粒子的有限平流扩散过程的基本理解，包括冷冻干燥、过滤和沉降等相关过程。该奖项反映了 NSF 的法定使命，并被视为值得通过使用基金会的智力优点和更广泛的影响审查标准进行评估来支持。