Heat transfer in nanostructures for solid-state energy conversion

Solid-state energy conversion technologies such as thermoelectric and thermionic refrigeration and power generation require materials with low thermal conductivity but good electrical conductivity and Seebeck coefficient, which are difficult to realize in bulk semi-conductors. Nanostructures such as superlattices, quantum wires, and quantum dots provide alternative approaches to improve the solid-state energy conversion efficiency through size and interface effects on the electron and phonon transport. In this review we discuss recent research and progress using nanostructures for solid-state energy conversion. The emphasis is placed on fundamental issues that distinguish energy transport and conversion between nanoscale and macroscale, as well as heat transfer issues related to device development and property characterization.