Aliovalence-doped thermoelectrics

In a recent Nature Physics article, Han et al. demonstrate the efficacy of aliovalent doping in simultaneously optimizing the electrical and thermal properties of half-Heusler NbFeSb thermoelectrics. Heavy aliovalent dopant slows both optical and acoustic phonons via effective screening of Coulomb interactions and avoided crossing, respectively. Simultaneous optimization offers a pathway for high-efficiency thermoelectrics.