Thermoelectrics, a direct energy conversion technology between thermal and electrical energy, could generate significant impact on many energy-related issues the world is facing. Over the past decade, significant progress has been made in creating better nanostructured materials to improve the efficiency of thermoelectric energy conversion. However, to date, most efforts have been focused on low temperature thermoelectric materials for refrigeration applications. High temperature nanostructured thermoelectric materials, which could harvest electricity from waste heat, have not received as much attention. Boron carbides, a class of complex ceramic materials, have been projected as promising candidates for thermoelectric applications. Boron carbide nanowires, with desirable confinement effects to the transport of charge and energy carriers, could have even better thermoelectric performance than bulk boron carbides. In this project, the fundamental structure-property relations for boron carbide nanowires of different diameters, crystalline structures, and compositions are being constructed, which is critical for manufacturing the best performance boron carbide nanowires for high performance thermoelectric energy conversion. The project has integrated research and education components to train graduate students in an interdisciplinary environment, and to extend the impact to underrepresented minorities and K-12 students through demonstration of the importance of nanomaterials in energy technology.
TECHNICAL DETAILS: This project aims at constructing the structure-transport property relations of boron carbide nanowires, a class of complex ceramic nanowires that is promising for high temperature thermoelectric power generation. The approach is to integrate rational materials synthesis, transport property measurements at individual nanostructure level, thorough structure characterization of measured samples, and theoretical analysis to achieve in-depth understanding of charge and energy transport. The structure-property relation is critical to design and fabricate boron carbide nanowires with the best thermoelectric properties, which could generate significant impact on industrial waste heat recovery. The project tackles an area where little research has focused to date, namely, nanostructured high temperature thermoelectrics, that has the potential to make use of waste heat. Successful implementation of the project can lead to an in-depth understanding of transport properties of boron carbide nanowires, and create a class of high performance thermoelectric nanomaterials. The project trains students in an interdisciplinary environment, which prepare them well for today's cutting-edge multidisciplinary research.
