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.
