US-Ireland R&D Partnership: Mechanics of the Formation and Function of 2D Material Pleats

美国-爱尔兰 R

• 批准号: 2041662
• 负责人: Robert Carpick
• 金额: $ 53万
• 依托单位: University of Pennsylvania
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-09-01 至 2025-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2041662&HistoricalAwards=false
• 关键词: US; Ireland; R&D; Partnership; Mechanics

A central challenge in fulfilling the tremendous potential of nanoscale materials is that they are hard to control, manipulate, and mass-produce into useful structures and devices. This is in part due to the small size, their tendency to stick to one another, and their susceptibility to thermal vibrations. Thus, it is important to understand the nanoscale forces behind these effects, including adhesion and friction. The key to developing this knowledge lies in understanding and taking advantage of the beneficial aspects of these forces. One such case is the phenomenon of self-assembly, where nanoscale materials organize themselves into ordered structures. This award supports research which aims to understand how forces conspire in a particularly striking case of such behavior: the spontaneous formation of long, folded pleats of atomically thin, two-dimensional materials that can be seen with a simple magnifying glass. Experiments and simulations will be used to understand what controls and drives this process, conducted by an interdisciplinary team of collaborators who will combine their unique and ideal expertise to tackle the problem. The goal is to uncover the mechanical principles governing the formation of these pleats. The work has broad scientific and technological impact, as it focuses on the fundamental mechanics of these materials but with a view toward controlling their assembly and construction into useful structures and devices. The award will also support educational outreach by training undergraduate, graduate, and postdoctoral researchers. This will include mentored international personnel exchanges between the collaborators’ laboratories; engaging K-12 students and the public in outreach events; and developing an online short course for researchers about the nanoscale mechanics of these materials. Two-dimensional material pleats are long, folded structures that have been recently discovered. Their formation is triggered by puncturing a substrate-supported two-dimensional materials like graphene with a nanoindenter tip. This is followed by subsequent growth of a folded ribbon of the two-dimensional material, up to 10’s of micrometers. However, little is known about the fundamental mechanics of these remarkable structures. While a continuum-level model has been developed that gives some qualitative insight into pleat formation, there is no atomistic-level understanding of the mechanisms that govern the phenomenon. This project addresses this gap by performing an atomistically-informed investigation of the mechanics of pleat formation and their mechanical properties once formed. Doing this requires an effort that integrates material synthesis, nanomechanical characterization, and atomistic and coarse-grained simulations. An interdisciplinary team of collaborators from the US, the Republic of Ireland, and Northern Ireland, UK will use their unique combination of expertise to tackle this problem. The primary goal is to uncover the fundamental mechanical principles governing pleat nucleation, growth, and interaction with the environment. A long-term, broad impact of this work will be to establish design principles for fabricating useful devices from the wide and growing array of two-dimensional and thin materials.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.

实现纳米级材料的巨大潜力的核心挑战是，它们很难控制，操纵和大规模生产成有用的结构和设备。这部分是由于尺寸很小，它们彼此坚持的趋势以及对热振动的敏感性。这是重要的是要了解这些效果背后的纳米级力量，包括广告和摩擦。发展这种知识的关键在于理解和利用这些力量的有益方面。一种情况是自组装现象，纳米级材料将自己组织成有序结构。该奖项支持研究，旨在了解这种行为特别引人注目的情况下强迫如何共谋：赞助商样形成的长而折叠的原子上薄的二维材料，可以用简单的放大镜可以看出。实验和模拟将用于了解由跨学科的合作者团队进行的控制和驱动过程，这些团队将结合其独特而理想的专业知识以解决问题。目的是揭示有关这些乐趣形成的机械原理。这项工作具有广泛的科学和技术影响，因为它着重于这些材料的基本机制，但要将其组装和构造控制为有用的结构和设备。该奖项还将支持培训本科，研究生和博士后研究人员的教育宣传。这将包括合作者实验室之间的指导国际人员交流；吸引K-12学生和公众参加外展活动；并为研究人员开发有关这些材料的纳米级机制的在线短期课程。二维物质褶皱是最近发现的长折叠结构。它们的形成是通过刺穿底物支撑的二维材料（如用纳米Indenter尖端的石墨烯）触发的。接下来是二维材料的折叠色带的随后生长，最多10毫米。但是，对于这些杰出结构的基本机制知之甚少。尽管已经开发了一个连续的模型，该模型对褶皱形成有一些定性的见解，但对控制现象的机制没有原子级的理解。该项目通过对褶皱形成机械及其机械性能的原子化投资来解决这一差距。这样做需要一项努力，以整合材料合成，纳米力学的特征以及原子和粗粒的模拟。来自美国，爱尔兰共和国和英国北爱尔兰的合作者的跨学科团队将利用其独特的专业知识来解决这个问题。主要目标是揭示有关褶皱成核，生长和与环境相互作用的基本机械原理。这项工作的长期，广泛的影响将是建立设计原则，以制造一系列二维和薄薄材料中的有用设备。该奖项反映了NSF的法定任务，并被认为是通过基金会的智力优点和更广泛影响的评估标准，认为通过评估来获得珍贵的支持。