Abstract Scope |
For thermoelectric conversion realization, dimensionless figure of merit ZT, described as S2s T/k, is required to be high, where S is Seebeck coefficient, s is electrical conductivity, and k is thermal conductivity. However, the correlation among three thermoelectric properties makes it difficult to increase ZT.
Nanostructuring is one of the promising approaches to increase ZT by controlling three thermoelectric properties, where nanostructure design and well-controlled formation of nanostructures are required.
We have developed various kinds of original well-controlled nanostructures: For example, Si-based films including ultrasmall nanodots of group IV semiconductor with controlled interfaces, strains, crystal orientations, and compositions. Therein, phonon was coherently scattered on nanoscale, resulting in the ultralow k and high s. For power factor enhancement, we formed Ca-intercalated multi-layered silicene films. By modifying the silicene bucked structure, S was enhanced with high s. In this talk, we will present our nanostructuring strategies for thermoelectric performance enhancement. |