Thermoelectric Properties of Carbon-rich Boron Carbide Nanocomposites

Boron carbide is widely used in industry and military because of its low mass-density, super high hardness, good electric conductivity, and excellent mechanical properties. The material is also one high-temperature thermoelectric compound capable for applications above 1000 ^oC. However, its thermoelectric properties, such as Seebeck coefficient and figure-of-merit, are low and need to be enhanced significantly for high-efficiency energy applications. Nanostructuring is an effective approach to improve thermoelectric properties. Here boron carbide nanomaterials with various chemical composites are prepared and their physical properties (crystallinity, chemical composition, band-gap, defects etc) are characterized. The as-synthesized nanomaterials are then bottom-up-ed to bulk nanocomposites. Thermoelectric properties of the bulks are measured. Their microstructures are characterized by X-ray powder diffraction, scanning electron microscopy, transmission electron microscopy, Raman scattering, and UV-vis spectroscopy etc. The enhanced performances of the carbide nanocomposites are like a result of their unique nanostructures.