CAREER: Multi-scale Mechanical Behavior of Quantum Dot Nanocomposites: Towards Data-driven Automatic Discovery of High-performance Structures

职业：量子点纳米复合材料的多尺度机械行为：迈向数据驱动的高性能结构的自动发现

• 批准号: 2145604
• 负责人: Ozgur Keles
• 金额: $ 59.93万
• 依托单位: San Jose State University Foundation
• 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: 2022-09-01 至 2027-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2145604&HistoricalAwards=false
• 关键词: CAREER; Multi; scale; Mechanical; Behavior

This Faculty Early Career Development (CAREER) grant will support fundamental research on processing-structure-mechanics relationships in thermosetting nanocomposites containing ultrasmall two-dimensional quantum dot nanoparticles. Thermosetting polymers are used by aerospace, defense, transportation, electronics, and many other industries. Moreover, fiber reinforced thermoset composites dominate high-performance structural applications. Despite their common use, thermosets are brittle. Quantum dot nanoparticles, on the other hand, simultaneously enhance the toughness and strength of the thermosets. Yet, we don’t know how the ultrasmall two-dimensional particles enhance mechanical properties of the thermosets. The researched project will reveal the molecular origins of these enhancements using systematic simulations and experiments. This new knowledge is potentially transformative because quantum dots can enhance all the other larger-scale-filler composites, such as continuous fiber, graphene, and carbon nanotube composites. The education objective is to create open-source virtual reality engineering education tools and cultivate creative engineers. Unique collaborative design projects are planned to enhance student creativity that can impact innovation potential of the next-generation engineers. Outreach activities will also be performed in the elementary/high schools that serve underrepresented groups in the Silicon Valley.This study will improve our understanding of molecular level damage/deformation mechanisms as well as macroscopic fracture behavior of quantum dot nanocomposites. A specific focus is given to unique sub-20 nm structures containing up to three different quantum dot sizes that can react with thermosets and with each other. During this CAREER award, a combination of experimental, theoretical, computational, and informatics approaches will be used to answer: (a) How do quantum dot nanocomposites deform and break? (b) What are their main toughening mechanisms? The research objectives are to (i) reveal the load transfer and debonding mechanisms, (ii) identify the plastic deformation, damage initiation, and damage accumulation mechanisms, and (iii) observe, quantify, and model the toughening mechanisms in thermosets containing multi-modal size quantum dots below 20 nm. To achieve these objectives, molecular dynamics synthesis and mechanical tests will be performed. Positron annihilation time spectroscopy, in-situ Raman spectroscopy, in-situ synchrotron X-ray characterization, and ex-situ mechanical tests will be performed. A molecular dynamics-informed multi-scale model will be used to quantify the toughening behavior. In addition, a new atomistic data-driven predictive framework will be created to quickly discover nanocomposites with high mechanical performance.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.

这项教师早期职业发展（职业）赠款将支持对含有超巨大二维量子点纳米粒子的热固性纳米复合材料中的处理结构机械关系的基础研究。热固性聚合物由航空航天，国防，运输，电子产品和许多其他行业使用。此外，纤维增强的热固性复合材料主导了高性能结构应用。尽管它们常用，但另一方面，热固性量子点纳米颗粒只需增强热固体的韧性和强度即可。但是，我们不知道超质二维颗粒如何增强热固性的机械性能。研究的项目将使用系统的模拟和实验揭示这些增强功能的分子起源。这种新知识具有潜在的变革性，因为量子点可以增强所有其他大型填充物复合材料，例如连续纤维，石墨烯和碳纳米管组成。教育目标是创建开源虚拟现实工程教育工具并培养创意工程师。计划实现独特的协作设计项目，以增强学生创意，从而影响下一代工程师的创新潜力。外展活动还将在为硅谷中代表性不足的群体服务的小学/高中进行。这项研究将提高我们对分子水平损伤/变形机制的理解以及量子点纳米复合岩的宏观裂缝行为。特定的焦点是独特的低于20 nm结构，其中包含多达三个不同的量子点大小，它们可以与热固性和彼此反应。在这个职业奖中，将使用实验，理论，计算和信息性方法的结合来回答：（a）量子点纳米复合材料如何变形和破裂？ （b）他们的主要韧性机制是什么？研究目标是（i）揭示负载转移和脱束机制，（ii）确定塑性变形，损伤起始和损伤加速机制，以及（iii）观察，量化和模拟含有多模式尺寸量子点20 NM低于20 NM的热温器中的韧性机制。为了实现这些目标，将执行分子动力学合成和机械测试。将执行正电子歼灭时间光谱，原位拉曼光谱，原位同步加速器X射线表征和前坐PITU机械测试。分子动力学的多尺度模型将用于量化韧性行为。此外，将创建一个新的原子数据驱动的预测框架，以快速发现具有高机械性能的纳米复合材料。该奖项反映了NSF的法定任务，并通过使用基金会的知识分子优点和更广泛的影响审查标准来评估被认为是宝贵的支持。