CAREER: Novel Engineered Nanostructured Complex Oxide Thermoelectric Materials for High Temperature Power Generation

非技术描述：工业发电厂、来自涡轮机发动机和汽车的废气产生大量的热量，这些热量被无效地释放到环境中，从而浪费了大量的热能。提高我们能源基础设施和电力基础可持续性的一个潜在方法是利用热电发电机回收废热，热电发电机能够直接将温差转化为电能。 氧化物材料，例如新开发的无毒钴酸钙（CCO），由于其即使在高温下在空气中的稳定性，特别有希望应用于热电发电机。热电氧化物的能量转换效率目前低于传统热电材料，其发展面临的挑战是提高能量转换效率。这个CAREER项目探索了提高热电氧化物能量转换效率所必需的关键纳米结构科学和工程过程。该项目的教育方面涉及培训研究生和本科生，并扩大材料科学和工程研究中代表性不足的学生群体的参与。为了向更广泛的社会介绍热电材料和能源可持续性的新概念，高中教师通过西弗吉尼亚大学现有的教师研究经验促进知识计划参与该项目。高中教师们正在将实验室的经验收集在期刊上，并为他们的教室设计和开发关于能源应用的先进材料的教材。技术问题：目前热电氧化物的开发面临的挑战是提高转换效率，目前它比传统的热电材料低。该CAREER项目的目标是通过纳米结构工程方法改善氧化物CCO的能量转换性能。该项目通过实验合成/测量和透射电子显微镜，探索了具有工程纳米级夹杂物的CCO中的新型掺杂和热输运定制策略。特别是，该项目利用CCO中不同缺陷（包括掺杂剂和纳米级夹杂物）的协同组合来增强电输运性能并同时最小化热导率。该项目的成功完成预计将确定关键的纳米结构工程工艺，以提高氧化物陶瓷的能量转换效率，可用于高温应用，如化石能源发电厂和汽车的应用。虽然上述研究将对热电氧化物的发展产生直接影响，但从研究中获得的陶瓷材料纳米结构工程的基础知识将有助于许多其他陶瓷系统。这些系统包括用于燃气涡轮机的氧化物耐火材料和氧化物热障涂层，它们可以显著受益于设计的热导率降低。这个职业生涯项目非常注重本科和研究生阶段的研究和教育的整合，以开展先进陶瓷能源收集和纳米科学技术的前沿研究。

NON-TECHNICAL DESCRIPTION: Industry power plants, exhaust from turbine engines and automobiles generate an enormous amount of heat that is unproductively released into the environment, thereby wasting vast amount of thermal energy. A potential way to improve the sustainability of our energy infrastructure and electricity base is through waste heat recovery using thermoelectric power generators that possess the ability to directly transform temperature differentials into electrical power. Oxide materials, such as newly developed non-toxic calcium cobaltite (CCO) are particularly promising for applications in thermoelectric power generators because of their stability in air even at high temperatures. The current challenge for developing thermoelectric oxide is to improve the energy conversion efficiency, which is currently lower than that of the conventional thermoelectric materials. This CAREER project explores the key nanostructure science and engineering processes necessary to improve the energy conversion efficiency of thermoelectric oxide. The educational aspect of this project involves training both graduate and undergraduate students, and broadening the participation of underrepresented student groups in materials science and engineering research. To introduce the novel concept of thermoelectric materials and energy sustainability to the broader society, high school teachers are involved in the project through the existing Teachers Research Experience for the Advancement of Knowledge program at West Virginia University. The high school teachers are collecting their lab experiences in a journal, and designing and developing teaching materials about advanced materials for energy application for their classrooms.TECHNICAL DETAILS: The current challenge for developing thermoelectric oxide is to improve the conversion efficiency, which is currently lower than that of the conventional thermoelectric materials. The objective of this CAREER project is to improve the energy conversion properties of oxide CCO, through nanostructure engineering approaches. This project explores novel doping and thermal transport tailoring strategies in CCO with engineered nanoscale inclusions, through experimental synthesis/measurement and transmission electron microscopy. In particular, this project utilizes the synergetic combination of different defects including dopants, and nanoscale inclusions in CCO to enhance the electrical transport properties and minimize thermal conductivity simultaneously. The successful completion of this project is expected to identify the key nanostructure engineering processes necessary to improve the energy conversion efficiency of oxide ceramics that could be utilized for high temperature applications, such as applications in fossil energy power plants and automobiles. While the above research will have direct impact on the development of thermoelectric oxide, the fundamental knowledge on the nanostructure engineering of ceramic materials gained from the research will be instrumental to many other ceramic systems. Those systems include oxide refractory materials and oxide thermal barrier coatings for gas turbines that can benefit significantly from engineered thermal conductivity reductions. This CAREER project has a strong focus on integration of research and education at both the undergraduate and graduate levels, for carrying out cutting-edge research in advanced ceramics for energy harvesting, and nanoscale science and technology.