CAREER: Understanding Nanoparticle Adhesion to Guide the Surface Engineering of Supporting Structures

职业：了解纳米粒子粘附以指导支撑结构的表面工程

• 批准号: 1844739
• 负责人: Tevis Jacobs
• 金额: $ 50万
• 依托单位: University of Pittsburgh
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-04-01 至 2024-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1844739&HistoricalAwards=false
• 关键词: CAREER; Understanding; Nanoparticle; Adhesion; Guide

This Faculty Early Career Development (CAREER) Program grant supports fundamental research on metal nanoparticles, a class of materials that can be as small as 10 atoms in diameter and are widely used in advanced technologies such as catalysis. A critical challenge in the use of these nanoparticles is their loss of functionality via particle coarsening; a phenomenon in which the average particle size increases over time, thus degrading their performance. This grant seeks to mitigate such coarsening allowing for improved performance, thus advance knowledge to sustain global leadership in these critical materials technologies and aid in the development of national prosperity. Coarsening is countered through the use of stabilizing support materials, but at present these materials are mostly found through time-consuming and costly trial-and-error testing. The present research seeks to enable the rational design of new and better stabilizing support materials by elucidating the dependence of particle coarsening on the supporting surface structure. The grant develops new approaches to measure the attachment and stability of nanoparticles on well-defined surfaces under various conditions, enabling the rational engineering of surfaces to optimize the performance and lifetime of the nanoparticles. Ultimately, more stable nanoparticles will lead to significant advances in human and environmental health, clean energy, and more efficient manufacturing. Educational activities include collaborates with the University of Pittsburgh's School of Education and a local elementary school to create and nationally disseminate surface engineering focused curricular units for 6th-to-8th-grade students and professional development training modules for teachers. Nanoparticle coarsening occurs by two mechanisms, atomic diffusion (Ostwald ripening) and particle migration and coalescence; both are hypothesized to depend exponentially on the strength of adhesion between the nanoparticle and its substrate. The research will investigate this link using in situ adhesion tests in a transmission electron microscope, thus enabling direct measurements of adhesion energy with simultaneous sub-nm-scale materials characterization for individual nanoparticles. The research objective is to establish structure-function relationships that link surface chemistry, crystallinity, and morphology to nanoparticle adhesion and the rate of particle coarsening. The central hypothesis is that the substrate surface can be rationally modified to tune adhesion, and thus control the rate of particle coarsening. The knowledge developed will improve performance in applications of metal nanoparticles on oxide supports, specifically: plasmonic sensors for detection of pollutants and as biosensors for disease; nanophotonics for improved conversion of solar energy; and heterogeneous catalysis, which contributes to the production chain of one-third of the US gross national product.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.

这项学院早期职业发展(Career)计划拨款支持金属纳米颗粒的基础研究，金属纳米颗粒是一种直径小至10个原子的材料，广泛应用于催化等先进技术。使用这些纳米粒子的一个关键挑战是它们因颗粒粗化而失去功能；这种现象是平均颗粒尺寸随着时间的推移而增大，从而降低它们的性能。这笔赠款旨在缓解这种粗制滥造，从而改善业绩，从而增进知识，以保持在这些关键材料技术方面的全球领先地位，并帮助发展国家繁荣。粗化是通过使用稳定支持材料来对抗的，但目前这些材料大多是通过耗时和昂贵的反复试验来找到的。本研究旨在通过阐明颗粒粗化与载体表面结构的关系，来合理设计新的、更稳定的载体材料。这笔赠款开发了新的方法，在各种条件下测量纳米颗粒在定义良好的表面上的附着和稳定性，使表面的合理设计能够优化纳米颗粒的性能和寿命。最终，更稳定的纳米粒子将在人类和环境健康、清洁能源和更高效的制造方面取得重大进展。教育活动包括与匹兹堡大学教育学院和当地一所小学合作，为6至8年级学生创建并在全国传播以表面工程为重点的课程单元，以及为教师提供专业发展培训模块。纳米颗粒粗化通过两种机制发生，原子扩散(Ostwald熟化)和颗粒迁移和合并；这两种机制都被假设为指数依赖于纳米颗粒与其底物之间的粘合强度。这项研究将使用透射电子显微镜中的原位附着测试来研究这种联系，从而能够直接测量附着能，同时对单个纳米颗粒进行亚纳米尺度的材料表征。研究的目标是建立结构-功能关系，将表面化学、结晶度和形态与纳米颗粒的附着力和颗粒粗化率联系起来。中心假设是，可以对基材表面进行合理的修饰，以调整附着力，从而控制颗粒粗化的速度。所开发的知识将提高金属纳米颗粒在氧化物载体上的应用性能，特别是：用于检测污染物和用作疾病生物传感器的等离子传感器；用于提高太阳能转换的纳米光子学；以及多相催化，其贡献了美国国民生产总值的三分之一。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

Contact.engineering—Create, analyze and publish digital surface twins from topography measurements across many scales

Contact.engineering – 根据多种尺度的地形测量创建、分析和发布数字表面双胞胎

• DOI: 10.1088/2051-672x/ac860a
• 发表时间: 2022
• 期刊: Surface Topography: Metrology and Properties
• 作者: Röttger, Michael C.;Sanner, Antoine;Thimons, Luke A.;Junge, Till;Gujrati, Abhijeet;Monti, Joseph M.;Nöhring, Wolfram G.;Jacobs, Tevis D. B.;Pastewka, Lars
• 通讯作者: Pastewka, Lars

Scale-dependent roughness parameters for topography analysis

用于形貌分析的尺度相关粗糙度参数

• DOI: 10.1016/j.apsadv.2021.100190
• 发表时间: 2021
• 期刊: Applied surface science advances
• 影响因子: 6.2
• 作者: Sanner, Antoine;Nohring, Wolfram G.;Thimons, Luke A.;Jacobs, Tevis D.;Pastewka, Lars
• 通讯作者: Pastewka, Lars