CAREER: Tuning Interface Atomic Structure and Composition for Fast Ion Conduction

非技术描述：陶瓷材料是当前和未来能量转换和存储技术的关键部件，如燃料电池、电池和用于生产氢气和处理二氧化碳的设备。改进这些技术有赖于了解和提高关键陶瓷材料的离子导电性。这项研究产生的新知识将产生高性能工程材料的设计规则，并使前所未有的陶瓷能够用于能量转换、能量存储和化学转换应用。该项目结合了最先进的纳米材料制备方法和先进的电子显微镜表征，在原子水平上解释了陶瓷材料的行为。这项研究被整合到一项新的推广和教育活动中，该活动让高中生和教师参与丰富的科学和技术活动，并旨在将不同的学生培养成进入科学和工程领域的渠道。新的“成像和记录的科学、技术和艺术”(STAIR)推广活动让来自当地低收入地区代表性不足群体的高中教师和学生在创作艺术的同时学习成像物理和技术。STAIR利用一般知识来接触和教育成像硬件(相机、显微镜)、物理(光学、颜色、辐射)、艺术(摄影、摄像)和技术(虚拟现实、计算机视觉)。由该项目资助的材料科学研究生在先进的纳米材料合成和表征方面进行培训，为他们在制造、清洁能源和半导体的研究和开发中的就业做准备。技术细节：这项研究阐明了离子导电陶瓷材料中材料缺陷的原子结构、化学组成和氧离子导电性之间的联系。研究了基于脉冲激光沉积的纳米加工技术合成的模型多层薄膜和双晶中的二维缺陷(界面)。这种界面对各种工程材料的电学和电化学性能至关重要，而不仅仅是电陶瓷。结合使用能够直接成像和识别原子的先进的电子显微镜成像和光谱技术的实验，以及阴离子扩散系数的模拟，回答了围绕界面附近移动离子行为的基本问题。这项研究试图推进离子导电陶瓷导电性的基本理论，揭示跨界面质量传输的原子水平机制，并最终解释如何最佳地设计材料以获得最佳的电性能。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。

NON-TECHNICAL DESCRIPTION: Ceramic materials are key components in current and future energy conversion and storage technologies, such as fuel cells, batteries, and devices used to produce hydrogen gas and process carbon dioxide. Improving these technologies relies on understanding and enhancing the ionic conductivity of crucial ceramic materials. New knowledge produced by this research will yield design rules for high-performance engineering materials, and enable unprecedented ceramics for energy conversion, energy storage, and chemical conversion applications. This project combines state-of-the-art nanomaterials fabrication methods, and advanced electron microscopy characterization to explain the behavior of ceramic materials at the atomic level. The research is integrated into a novel outreach and education activity which engages high school students and teachers in activities rich in science and technology, and designed to develop a pipeline of diverse students into science and engineering fields. The new “Science, Technology and Art of Imaging and Recording” (STAIR) outreach activity is bringing high school teachers and students from underrepresented groups in local low-income areas to learn about imaging physics and technology while making art. STAIR leverages general knowledge to engage and educate about imaging hardware (cameras, microscopes), physics (optics, colors, radiation), art (photography, videography), and technology (virtual reality, computer vision). Materials science graduate students funded by this project are trained in advanced nanomaterials synthesis and characterization, preparing them for employment in manufacturing, and research and development in clean energy and semiconductors.TECHNICAL DETAILS: This research elucidates the links between atomic structure, chemical composition, and oxygen anion conductivity across material defects in ion-conducting ceramic materials. Two-dimensional defects (interfaces) are investigated in model multilayer thin films and bicrystals synthesized by state-of-the-art nanofabrication techniques based on pulsed laser deposition. Such interfaces are key to the electrical and electrochemical performance of a wide variety of engineering materials, not just electroceramics. A combination of experiments using advanced transmission electron microscopy (TEM) imaging and spectroscopy techniques capable of directly imaging and identifying atoms, and simulations of anion diffusivity, answer fundamental questions surrounding the behavior of mobile ions near interfaces. This research is attempting to advance fundamental theories of electrical conductivity in ionically-conducting ceramics, uncover atomic-level mechanisms of mass transport across interfaces, and ultimately explain how to best design materials for optimal electrical 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.