Multiscale approaches to thermoelectric materials and devices

Performance of thermoelectric materials and devices depends upon various features on different levels from microscopic to macroscopic scales. On the atomic scale, to find new multi-component compounds with complex electronic and crystal structures is a way to high-Z thermoelectric materials. On the nano-scale, quantum wells, wires and dots are considered to be the dawn for breaking the traditional barrier of ZT/spl sim/1 existing for several decades. From the point of view of microstructure, inhomogeneities in thermoelectric materials, such as interfaces/grain-boundaries and inclusions, have significant influences on their thermoelectric properties. On the macroscopic scale, the thermoelectric device functions depend on thermoelectric materials used for building the device and device configuration (such as multistage or segmented devices). This review briefly presents the state-of-the-art and perspectives in the multiscale understanding of thermoelectric materials and devices.