The Doping Strategies for Modulation of Transport Properties in Thermoelectric Materials

Abstract

AbstractDoping is a key method employed in semiconductor technology for tuning the carrier‐density‐dependent electrical properties. In thermoelectric materials, which are typically heavily doped semiconductors, more impact factors are needed to be considered due to the heavy dose doping compared to normal semiconductors beyond carrier concentration optimization, such as band structure modification, carrier scattering mechanism and even thermal transport property. In this review, the doping effect determined by the intrinsic band features and vice versa the influence of dopants on band structure is first illustrated; and then introduce the approaches to overcoming the dilemma in effective doping caused by the temperature‐dependent optimal carrier concentration. Second, the strategies including rational vacancy design, proper selection of dopants and lattice purification toward high efficient doping and weakened carrier scattering strength are reviewed. Third, the recent discovery of the effect of dopant on thermal transport is highlighted covering the dopant‐induced local lattice distortion and exceptional strong electron‐phonon coupling. Finally, a perspective is given for the doping strategies to further boost the performance of thermoelectric materials.