Collaborative Research: Guiding synthesis of nanoparticles with nanometric phase diagram and in situ X-ray diffraction

合作研究：用纳米相图和原位X射线衍射指导纳米颗粒的合成

• 批准号: 2004837
• 负责人: Yifei Mo
• 金额: $ 25.08万
• 依托单位: University of Maryland, College Park
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-08-01 至 2024-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2004837&HistoricalAwards=false
• 关键词: Collaborative; Research; Guiding; synthesis; nanoparticles

Non-technical SummaryMetallic nanostructures are widely used in many important applications, such as catalysts, energy storage and biomedical engineering. The synthesis of metallic nanostructures is more difficult than that of bulk metals and alloys. Conventional phase diagrams are used as road maps to guide the synthesis and processing of bulk metals and alloys, but they are not suitable for nanoparticles, which have drastically increased surface area and surface energy. Nanometric phase diagrams as the counterpart of conventional phase diagram is highly desired. This project aims to establish nanometric phase diagrams for guiding synthesis of nanoparticles using advanced experimental characterizations and atomistic modeling. Experiments are conducted to observe the formation and growth of metal/alloy nanoparticles in real time, and atomistic modeling provides theoretical understanding of these processes. The synthesis of new forms of metal and alloy nanoparticles is guided by the novel nanometric phase diagrams. This project adds to the fundamental knowledge about the formation process of nanoparticles, and provides a new avenue of synthesizing novel nanoparticles for a range of applications. The scientific findings from this project are integrated as education components into undergraduate and graduate courses. Students at different stages of education participate through a variety of research, education, and outreach activities. Technical SummaryMany metallic nanostructures show unique physical and chemical properties that are different from their bulk forms. Previous researches have demonstrated that these metallic nanomaterials often form phases that are not stable in conventional phase diagram. However, it is not yet fully understood why this can happen and in what condition this would happen. This project aims to answer these fundamental questions via a novel approach combining computational and experimental research efforts. State-of-the-art in situ X-ray characterization techniques are developed and employed to monitor the nucleation and growth processes of metallic nanoparticles in solutions, both qualitatively and quantitatively. First principles computations are used to evaluate the bulk, surface and total energies of nanoparticles in different synthesis conditions and at different length scales. By coupling computational and experimental investigations, the formation mechanisms of metallic nanostructures are revealed and the nanometric phase diagrams are established to predict and guide the syntheses of metallic nanomaterials. The findings and outcome of this project have impacts and implications in multiple fields, such as solid state chemistry, metallurgy, and nanotechnology.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.

非技术总结纳米结构在许多重要的应用中广泛使用，例如催化剂，储能和生物医学工程。金属纳米结构的合成比散装金属和合金的合成更加困难。常规的相图用作路线图，以指导散装金属和合金的合成和加工，但它们不适合纳米颗粒，纳米颗粒大大增加了表面积和表面能。高度需要纳米相图作为常规相图的对应物。该项目旨在建立使用先进的实验特征和原子模型来指导纳米颗粒合成的纳米相图。进行实验以实时观察金属/合金纳米颗粒的形成和生长，而原子建模提供了对这些过程的理论理解。新型金属和合金纳米颗粒的合成由新型纳米相图指导。该项目增加了有关纳米颗粒形成过程的基本知识，并为一系列应用提供了合成新型纳米颗粒的新途径。该项目的科学发现是作为教育组成部分纳入本科和研究生课程的。不同教育阶段的学生通过各种研究，教育和外展活动参与。技术总结金属纳米结构显示出独特的物理和化学特性，与它们的大量形式不同。先前的研究表明，这些金属纳米材料通常形成在常规相图中不稳定的相。但是，尚不完全了解为什么会发生这种情况以及在什么情况下发生。该项目旨在通过结合计算和实验研究工作的新方法来回答这些基本问题。开发和采用了最先进的原位X射线表征技术来监测溶液中金属纳米颗粒的成核和生长过程，无论是在定性和定量上。 第一原理计算用于评估在不同的合成条件下和不同长度尺度下的纳米颗粒的大量，表面和总能量。通过耦合计算和实验研究，揭示了金属纳米结构的形成机理，并建立了纳米相图，以预测和指导金属纳米材料的合成。该项目的发现和结果在多个领域都具有影响和影响，例如固态化学，冶金和纳米技术。该奖项反映了NSF的法定任务，并被认为是值得通过基金会的知识分子优点和更广泛的影响评估来评估的。标准。