CAREER: Effects of Anelastic Relaxation of Defect Complexes on the Mechanical Behavior of Oxide Ceramics

非技术描述：具有高离子或混合离子电子电导率的氧化物陶瓷是目前高效环保能源技术的重要材料，包括固体氧化物燃料电池和电池。该项目在基本层面上解决了氧化物陶瓷中原子缺陷与其在高温和机械应力综合作用下的机械行为之间的关系。这个项目的结果预计将大大提高对氧化物中原子缺陷形成和相互作用的认识，这是今天进一步开发用于能源产生、转换和储存的可靠和耐用设备所需要的。该项目整合了研究、教育和推广活动，重点是了解极端条件下氧化物的复杂行为，重点是让研究生、本科生、K-12学生和代表性不足的群体参与能源应用新材料的研究。技术细节：尽管在理解氧化物中点缺陷的化学、结构和动力学及其对输运性质的影响方面取得了重大进展，但点缺陷在施加载荷下的行为及其对温度相关机械性能的影响仍然难以捉摸。该项目的主要目标是通过实验量化点缺陷的类型、浓度和关联对具有高离子或混合离子电子导电性的纯和掺杂二元和三元氧化物陶瓷的机械性能的影响。此外，本项目通过将实验结果与不同条件下的结构、化学和点缺陷相互作用联系起来，为陶瓷中的点缺陷理论做出了贡献，并对这些缺陷对机械行为的作用有了更全面的理解。本项目利用新的实验和计算工具来更好地理性化高温下氧化物的结构和热力学性能之间的关系。该资助进一步加强学生的教育和研究经验，让他们密切参与材料科学和可再生能源领域的新课程的实践研究和开发。

NON-TECHNICAL DESCRIPTION: Oxide ceramics with high ionic or mixed ionic-electronic conductivity are currently essential materials for highly-efficient and environmentally-friendly energy technologies, including solid oxide fuel cells and batteries. The project addresses, on a fundamental level, the relationship between atomic defects in oxide ceramics and their mechanical behavior under the combined effects of elevated temperature and mechanical stresses. The results of this project are expected to advance significantly the knowledge on formation and interaction of atomic defects in oxides that is needed today for further development of reliable and durable devices for energy generation, transformation, and storage. This project integrates research, educational and outreach activates that are focused on understanding complex behavior of oxides under extreme conditions, with an emphasis on involving graduate, undergraduate, K-12 students and underrepresented groups in research on novel materials for energy applications. TECHNICAL DETAILS: Although, significant progress has been achieved in understanding the chemistry, structure and kinetics of point defects in oxides and their effect on transport properties, the behavior of point defects under applied loads and their effects on temperature-dependant mechanical properties remain elusive. The main objective of the project is to quantify experimentally the effects of type, concentration and association of point defects on the mechanical properties in pure and doped binary and ternary oxides ceramics with high ionic or mixed ionic-electronic conductivity. Furthermore, this project contributes to the theory of point defects in ceramics and generates a more comprehensive understanding of the role that these defects have on mechanical behavior by linking experimental results to structure, chemistry and point defects interactions under different conditions. New experimental and computational tools are utilized in this project to better rationalize relationship between structural and thermo-mechanical properties of oxides at elevated temperatures. The grant further strengthens the educational and research experience of students through their close involvement in hands-on research and development of new courses in areas of materials science and renewable energy.