Nanostructured Thermoelectric Materials

Abstract

Thermoelectric energy conversion technique has been used as the power supply for the deep-space exploring missions, now showing notable advantages to harvest the widely distributed waste heat and convert the abundant solar energy into electricity. Recent years have witnessed big advances in the nanostructure thermoelectric bulk materials in both synthesis technique and fundamental understanding. In this book chapter, various strategies towards novel nanostructured bulk material with improved ZT value were summarized according to different synthesis routes, including reduced grain size by physical, or chemical powder metallurgy method, surface or interface modification by introduce second phase, and forming precipitations by molten casting method. We also theoretically explained the importance of the interface/boundary scattering to phonon and electron within the various thermoelectric materials. We finally proposed a new nanocomposite with ordered nanostructure, named as “ordered nanocomposite”, which is expected to achieve new breakthrough if we could create some sort of channels for the easy transport of electrons but difficult for the phonons.