GOALI - Collaborative Research: The Impact of Chemically Induced Stresses on Kinetic Processes and Degradation Mechanisms in Non-Stoichiometric Oxides

非技术描述：本研究项目侧重于几种在能源相关应用中很重要的氧化物材料。感兴趣的中心现象与由成分变化（例如，在电池材料中添加和去除锂）产生的内应力有关。该项目的具体发现将直接有助于开发用于混合动力和电动汽车的高能量密度锂离子电池的改进电极，以及用于燃料电池和催化的改进材料。知识转移是通过公共传播和与研究人员和通用汽车公司的直接互动进行的。技术细节：在离子材料中，内应力、材料缺陷、电化学现象和动力学过程（如扩散和相变）之间存在复杂的相互作用。这些压力导致固体氧化物燃料电池和锂离子电池正在开发的新材料的退化和性能限制。对这些压力相关问题的科学理解目前非常有限。在本项目中，对这些现象的研究是基于系统的、战略性的、理论与实验紧密结合的调查。布朗大学的努力采用精确的应力原位测量以及其他实验方法来开发新方法，用于探测各种复杂现象，其中应力与基本机制的相互作用知之甚少（例如，缺陷关联，晶界偏析，多组分扩散等）。对这些数据的解释依赖于密歇根州立大学的原子尺度模型。两所大学的学生和教师直接与吴琰博士和通用汽车的其他研究人员合作，以扩大教育成果和加强知识向工业转移的方式。从这个项目中获得的应力对动力学过程和降解机制的总体理解也与更广泛的离子固体有关。

NON-TECHNICAL DESCRIPTION: This research project focuses on several oxide materials that are important in energy related applications. The central phenomena of interest are linked to internal stresses that are created by changes in composition (for example, adding and removing lithium in a battery material). The specific findings from this project are contributing directly to the development of improved electrodes for high energy density lithium ion batteries for hybrid and electric vehicles, and improved materials for applications in fuel cells and catalysis. Knowledge transfer is occurring through both public dissemination and direct interactions with researchers and General Motors. TECHNICAL DETAILS: In ionic materials there is a complex interplay between internal stresses, defects in the material, electrochemical phenomena and kinetic processes (e.g., diffusion and phase transformations). These stresses lead to degradation and performance limitations in new materials that are being explored for both solid oxide fuel cells and lithium ion batteries. Scientific understanding of these stress-related issues is currently very limited. In this project, research into these phenomena is based on systematic and strategically planned investigations that closely integrate theory and experiments. The efforts at Brown University employ precise in situ measurements of stresses along with other experimental methods to develop novel approaches for probing a variety of complex phenomena where stress interactions with fundamental mechanisms are poorly understood (e.g., defect association, grain boundary segregation, multicomponent diffusion, etc.). Interpretation of these data relies on atomic scale modeling at Michigan State University. Students and faculty from both Universities are working directly with Dr. Yan Wu and other researchers at General Motors, in ways that expand educational outcomes and enhance knowledge transfer to industry. The overall understanding of stress effects on kinetic processes and degradation mechanisms obtained from this project is also relevant to a broader range of ionic solids.