More efficient materials are needed to expand the commercial applications of thermoelectric devices. CoSb3 is the most promising thermoelectric material to replace PbTe-based alloys. The binary skutterudite compound cobalt triantimonide CoSb3 is particularly interesting because it displays remarkable electrical properties. The overall performance of this material remains however low due to an excessive value of its lattice thermal conductivity.
Our approach to develop high-efficiency thermoelectric materials is to combine the chemistry and the size effects. Our group has already obtained CoSb3 nanowires using template synthesis and demonstrated compositional and crystalline requirements for this compound. We investigate thermoelectric properties and their dependence on size, composition and surface modifications.
The template-based technology for nanostructure synthesis is very versatile and the nanostructures can be made on virtually any substrate and template. Combining the phonon-glass-electron-crystal approach with the quantum confinement effects to create new thermoelectric materials has the potential to result in a significant improvement in the power to weight ratio of the thermoelectric device. Eventually, this technology has the potential to yield the ultimate goal for thermoelectric systems, efficient solid-state devices for cooling and harvesting waste thermal energy. Addressing these challenges requires an interdisciplinary approach, which is fueled by recent advances on thermoelectric nanostructures.