CAREER: Electrochemical Ceramics - Understanding the Gap between Localized and Collective Viewpoints of Electronic Structure

电化学陶瓷包括各种现有的和新兴的技术，包括气体传感器、燃料电池、气体分离膜和膜反应器。对电化学陶瓷的性能建模和开发性能改进的新材料的关键是对电子结构的深入了解。由于大多数电化学陶瓷都具有复杂的中长标度有序，从传统的电子结构定域或集体观点来看，它们的性质往往难以解释。为了更全面地了解电化学陶瓷中的电子结构，我们建议使用一种新的高灵敏度法拉第天平测量具有一般组成的LaSrCoFe氧化物(LSCF)的过渡金属钙钛矿中的定域和离域电子布居。这些测量将用于解释对电化学性质的平行研究，包括电子传输、离子缺陷结构、化学膨胀和应力以及催化活性。此外，PI目前正在开发一个新的本科实验室实验项目，将研究与教学相结合。该项目为本科生提供了在现代化学工程增长领域为博士水平的研究做出贡献的正式机会，产生的真实数据将被公布(而不仅仅是进入实验室报告)。通过这种方式，研究和本科教育走在同一条轨道上，有着相辅相成的议程。拟议的项目将为这一教育计划贡献一个实验，该教育计划与我们的电化学陶瓷研究计划相联系(并直接提供给我们)。学生将使用高温磁化率测量和田口分析方法筛选电子结构的新材料。这个项目将有助于我们对复杂材料中电子结构的广泛理解。这些结果对材料科学的所有分支都有普遍的兴趣，包括固态电化学、电子材料、陶瓷以及无机化学和物理学。该项目还将提供一类材料的电子结构的具体信息，对开发反应/分离膜和固体氧化物燃料电池的工作人员具有直接价值。首席研究员在这一领域有8年的学术经验和4年的工业经验，带来了强大的基础和实践观点的结合。这项工作具有很高的原创性，并为经过验证的实验技术贡献了几个新的进展。实验计划组织得很好，提议的机构拥有这一跨学科领域工作的世界级基础设施。此外，PI的职业发展计划将有助于在一个新的、令人兴奋的技术领域建立强大的基础研究和教育计划。该项目不仅将培养所在领域的个别科学家，还将以一种对双方都有利的方式将研究与教学紧密结合，并为本科生(CWRU的许多学生是女性和少数族裔)提供新的机会，在广泛的范围内参与尖端研究。这一方法为教学提供了一个新的模板，其他高等教育机构可能会从中受益。从研究和教育发展中获得的知识将通过文献广泛传播，并直接通过PI与工业和美国工程教育协会的紧密联系来传播。

Electrochemical ceramics encompass a variety of present and emerging technologies, including gas sensors, fuel cells, gas-separation membranes, and membrane reactors. Of critical importance to modeling the properties of electrochemical ceramics, and developing new materials with improved performance, is a strong understanding of electronic structure. Since most electrochemical ceramics possess complex intermediate-length scale order, their properties often defy explanation when viewed from traditional paradigms invoking localized or collective viewpoints of electronic structure. In order to gain a more complete understanding of electronic structure in electrochemical ceramics, we propose to measure the populations of localized and delocalized electrons in transition metal perovskites having general composition LaSrCoFe oxides (LSCF) using a novel high-sensitivity Faraday balance. These measurements will be used to interpret parallel studies of electrochemical properties, including electron transport, ionic defect structure, chemical expansion and stress, and catalytic activity. In addition, the PI is currently developing a new program of undergraduate laboratory experiments that integrate research and teaching. This program provides undergraduates with formal opportunities to contribute to Ph.D.-level research in modern growth areas of chemical engineering, producing real data that will be published (not just put into a lab report). In this way research and undergraduate education are on the same track, with a complementary agenda. The proposed project will contribute one experiment to this educational program, which is linked (and feeds directly into) our research program in electrochemical ceramics. Students will screen new materials for electronic structure using high-temperature magnetic susceptibility measurements and Taguchi analysis methods.%%%This project will contribute broadly to our understanding of electronic structure in complex materials. The results are of general interest to all branches of materials science, including solid-state electrochemistry, electronic materials, ceramics, as well as inorganic chemistry and physics. This project will also provide specific information about electronic structure in one class of materials, of immediate value to workers developing reaction/separation membranes and solid-oxide fuel cells. The principal investigator has 8 years academic and 4 years industrial experience in this field, bringing a strong mix of fundamental and practical perspectives. This work is highly original, and contributes several novel advances to proven experimental techniques. The experimental plan is well organized, and the proposing institution has a world-class infrastructure for work in this cross-disciplinary field. In addition, the career development plan of the PI will help establish a strong fundamental research and educational program in a new, exciting, area of technology. This program will not only educate individual scientists in its field, but will also tightly integrate research and teaching in a way that benefits both, and opens new opportunities for undergraduates (many of whom, at CWRU, are women and minorities) to participate in cutting-edge research on a broad scale. This approach provides a new template for teaching that other higher-educational institutions may benefit from. Knowledge gained from both research and educational development will be disseminated broadly through the literature, and directly through strong ties of the PI to industry and the American Society of Engineering Education.