Recent NMR Studies of Thermoelectric Materials

Thermoelectric materials can directly convert heat to electricity and are expected to lead to new devices to harvest waste heat for energy efficiency as well as new cooling technologies. Optimization of these properties requires tailoring vibrational properties as well as the entropy carried by electrical charges and spins. NMR measurements have been important for understanding these processes, providing a measure of anharmonic “rattling” phonon behavior, local fluctuations in charge carrier and magnetic properties, and atomic-scale symmetries and distortions within these materials. Here we report recent NMR results focusing on inorganic clathrates, skutterudites, oxides, noble metal chalcogenides, complex tellurides, and half-Heusler compounds in which high thermoelectric efficiencies have been reported.