CAREER: Atomic-level understanding of stability and transition kinetics of 3-dimensional interfaces under irradiation

科学家们正在进行一项令人着迷的任务，即创造出能够承受极端条件（如酷热、巨大压力甚至辐射）的超级坚韧材料。实现这一目标的一种方法是使用一种被称为“界面”的特殊成分，它就像纳米结构复合材料中的密码，决定了它们的独特性能。最近，一个令人兴奋的发现——揭示了一种被称为“3D界面”的新型界面。这就像给材料增加了一个新的维度，拥有巨大的潜力。然而，有一个问题——科学家们并不完全了解这些3D界面是如何工作的，尤其是当它们面临辐射时。这项研究的重点是使用一种叫做Cu-Nb的材料作为模型来解码这些3D界面的秘密。我们设定了两个主要目标：首先，在最小的原子水平上理解这些3D界面的内部工作原理，本质上是对它们进行超近距离观察。其次，探索这些3D界面在暴露于辐射时的反应。这项研究将招募高中生。其目的是通过提供研究机会、研讨会和动手实验室经验来激发下一代对科学和工程的兴趣，并帮助他们为能源行业的职业生涯做好准备。因为这些新材料有可能彻底改变我们建造东西的方式，特别是在核能领域，它们可以以更低的成本使核反应堆更安全。但其影响远不止于此——它可以影响各个领域，比如改进计算机晶体管等电子设备。因此，我们的使命是理解科学，培养学生的好奇心，为他们从事令人兴奋的职业做好准备，并最终与能源公司合作，创造一个更美好、更可持续的世界。技术概述PI的研究基本上侧重于开发具有特殊弹性的先进材料，以适应极端环境条件，包括高温，机械应力和辐射暴露。所讨论的材料的特点是其复杂的微观结构，特别是存在于其中的界面，这在决定其性能方面起着决定性的作用。随着3D界面的发现，材料科学的一个新维度被揭开，3D界面是一种相对较新的复杂的界面结构。这些3D界面表现出独特的特征，其特征是化学和结构属性的变化，沿着界面的法向跨越几个原子层到几十纳米。然而，控制三维界面行为的潜在机制，特别是对辐射的响应，仍然是一个有限理解的主题。本研究的重点是模型材料系统Cu-Nb，选择它是因为它适合探索3D界面的复杂性。主要研究目标包括量化三维界面结构中变化的短期结构和化学顺序，并预测和验证这些三维界面在暴露于辐射时的稳定性和转变动力学。这需要多方面的方法，包括综合实验和计算建模，交叉验证起着关键作用。这项工作的意义远远超出了材料科学的范围，进入了各种实用领域。它有可能帮助识别能够承受先进核反应堆中极端辐射条件的结构材料，这是核能领域一个持续和关键的挑战。此外，从这项研究中获得的见解可以与不同背景下的界面主导行为相关，包括先进电子元件（如FinFET晶体管）中超薄掺杂层的行为。除了它的技术优点，这项研究强烈强调推广和教育。它旨在激励和支持大学生和当地高中生，特别是那些来自弱势群体的学生，在能源行业寻求职业发展。这一教育组成部分包括研究机会、研讨会和动手实验室经验，与为能源部门及其他领域的一系列应用准备下一代材料科学家和工程师的总体目标保持一致。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

NON-TECHNICAL SUMMARYScientists are on a fascinating mission to create super-tough materials that withstand extreme conditions like blistering heat, immense pressure, and even radiation. One way to achieve this is to use a special ingredient known as "interfaces," which are like secret codes in nanostructured composites that determine their unique properties. Recently, an exciting discovery was made – unveiling a new type of interface known as a "3D interface." It's like adding a new dimension to materials and holds immense potential. However, there's a twist – scientists don't fully understand how these 3D interfaces function, especially when they face radiation. The focus of this research is to use a material called Cu-Nb as a model to decode the secrets of these 3D interfaces. Two primary goals have been set: firstly, to understand the inner workings of these 3D interfaces at the tiniest atomic level, essentially taking a super-close look at them. Secondly, to explore how these 3D interfaces respond when exposed to radiation. This research will recruit high school students. The aim is to inspire the next generation's interest in science and engineering by offering research opportunities, workshops, and hands-on lab experiences, and to help prepare them for careers in the energy industry. Because these new materials have the potential to revolutionize the way we build things, particularly in the realm of nuclear energy, they could make nuclear reactors safer at lower cost. But the impact goes far beyond that – it can influence various areas, such as improving electronic devices like computer transistors. So, this mission is about understanding science and nurturing students' curiosity, preparing them for exciting careers, and ultimately collaborating with energy companies to create a better, more sustainable world. TECHNICAL SUMMARYThe PI’s research fundamentally focuses on developing advanced materials with exceptional resilience to extreme environmental conditions, encompassing high temperatures, mechanical stress, and radiation exposure. The materials in question are distinguished by their intricate microstructures, particularly the interfaces existing within them, which play a defining role in dictating their properties. A novel dimension in material science was unveiled with the discovery of 3D interfaces, a relatively new and intricate class of interfacial structures. These 3D interfaces exhibit a unique character, characterized by variations in chemical and structural attributes spanning a few atomic layers to tens of nanometers along the interface's normal direction. However, the underlying mechanisms governing the behavior of 3D interfaces, particularly in response to radiation, have remained a subject of limited understanding. This research focuses on a model material system, Cu-Nb, chosen for its suitability in exploring the intricacies of 3D interfaces. The primary research objectives encompass quantifying the varying short-range structural and chemical ordering within 3D interface structures and predicting and validating the stability and transition kinetics of these 3D interfaces when exposed to radiation. This entails a multi-faceted approach involving integrated experiments and computational modeling, with cross-validation playing a pivotal role. The significance of this work extends far beyond the confines of material science and into various practical domains. It has the potential to help identify structural materials that can endure the extreme irradiation conditions found in advanced nuclear reactors, which is an ongoing and critical challenge in the realm of nuclear energy. Furthermore, the insights derived from this research could hold relevance for interface-dominant behavior in diverse contexts, including the behavior of ultra-thin doping layers in advanced electronic components, such as FinFET transistors. Beyond its technical merits, this research strongly emphasizes outreach and education. It seeks to inspire and support both university students and local high school students, especially those from underrepresented groups, in their pursuit of careers in the energy industry. This educational component encompasses research opportunities, workshops, and hands-on laboratory experiences, aligning with the overarching goal of preparing the next generation of materials scientists and engineers for a range of applications across the energy sector and beyond.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.