In Situ Imaging and Analysis of Solid Oxide Fuel Cell Anodes during Degradation

1134052 Pi Chiu这项研究的主要目标是开发能够在运行条件下直接观察固体氧化物燃料电池(SOFC)阳极的原位成像技术，并提供对SOFC阳极退化的科学和工程理解。实现这一目标将有助于提高SOFC的长期性能和可靠性，并使SOFC成为一种有效和可持续的能源转换的可行技术。使用新开发的透射式X射线显微镜(TXM)的高分辨率原位X射线成像将用于实现这一目标。PI将使用他在阿贡国家实验室先进光子源(APS)开发的硬X射线纳米层析成像技术，以非破坏性地获得运行中的SOFC阳极的高分辨率(32 Nm)三维图像。PI将开发现场X射线成像和光谱技术，以观察运行过程中的阳极退化，并进行详细的微观结构分析，以了解SOFC阳极的退化机理。老化的SOFC阳极将由洛桑联邦理工学院(EPFL)提供。SOFC阳极非原位三维无损成像的初步结果表明，操作时间对镍相颗粒粗化有显著影响。该项目将以初步结果为基础，阐明有关导致退化的机制和途径的基本知识。该项目将涉及两名研究生，并将有针对本科生和高中生的外展活动。智力方面的优点包括详细了解SOFC阳极在运行过程中由于镍的粗化而发生的退化及其对性能的影响。从这项研究中获得的知识将用于阐明降解机制，特别是不同粗化机制(Ostwald成熟、颗粒迁移和蒸发)的作用，它们发生的相应操作条件，以及这些机制如何以及在微观结构中起源于哪里。为这项研究组建的研究团队在SOFC领域开展了广泛的工作，包括SOFC材料的X射线成像、详细的电荷转移建模和测试、热应力和材料表征。这项研究的更广泛影响包括外部合作，这些合作将为我们的社会探索新的可持续能源技术。EPFL将提供SOFC样品，进行实验，并为模型验证提供数据。APS将提供同步加速器设施，使用32纳米分辨率的硬X射线显微镜系统对SOFC电极样品进行成像。在教育方面，PI将与康涅狄格州大学工程多样性计划密切合作，从超过25所当地高中挑选几名顶尖高中生，特别是来自代表人数不足的群体，在PI的实验室进行暑期实习。PI和他的学生将在EPFL和APS进行现场研究。

1134052 PI ChiuThe principal objective of this study is to develop in situ imaging techniques that allow the direct observation of solid oxide fuel cell (SOFC) anodes under operational conditions and provide a scientific and engineering understanding of degradation in SOFC anodes. Meeting this objective will help enhance SOFC long term performance and reliability and enable SOFCs as a viable technology for efficient and sustainable energy conversion. High resolution in situ x-ray imaging using a newly developed transmission x-ray microscope (TXM) will be used to achieve this goal. The PI will use hard x-ray nanotomography developed by him at the Argonne National Laboratory Advanced Photon Source (APS) to nondestructively obtain high resolution (32 nm) 3-D images of an operating SOFC anode. The PI will develop in situ x-ray imaging and spectroscopy techniques to observe anode degradation during operation and perform detailed microstructural analysis to understand degradation mechanisms in SOFC anodes. Aged SOFC anodes will be provided by the Ecole Polytechnique Federale de Lausanne (EPFL). Preliminary results obtained from ex situ nondestructive 3-D imaging of SOFC anodes indicate Ni-phase particle coarsening is significantly affected by operational time. This project will build on the preliminary results to elucidate fundamental knowledge regarding the mechanisms and pathways that cause degradation. This project will involve two graduate students and will have outreach activities for undergraduate and high school students.Intellectual merit includes a detailed understanding of SOFC anode degradation due to Ni coarsening during operation and its effect on performance. Knowledge obtained from this study will be used to elucidate degradation mechanisms, especially the role of different coarsening mechanisms (Ostwald ripening, particle migration, and evaporation), the corresponding operating conditions in which they occur, and how and where such mechanisms originate in the microstructure. The research team assembled for this study works extensively in the area of SOFCs including x-ray imaging of SOFC materials, detailed charge-transfer modeling and testing, thermal stress, and material characterization. Broader impacts of this study include external collaborations that will explore new sustainable energy technologies for our society. EPFL will provide SOFC samples, perform experiments, and provide data for model validation. APS will provide synchrotron facilities to image SOFC electrode samples using a 32 nm resolution hard x-ray microscope system. In terms of education, the PI will work closely with the UConn Engineering Diversity Program to identify several top high school students, especially from underrepresented groups, from over 25 local area high schools for a summer internship in the PI's lab. The PI and his students will engage in on-site research at EPFL and APS.