Enhancing thermoelectric performance of p-type Mg2Si through doping: A first-principles study

Abstract

This study investigates the structural and transport properties of p-type doped Mg₂Si using first-principles calculations. The focus is on doping Mg₂Si with Li, Ga, F, and LiGaF to enhance its thermoelectric performance. The formation energy ($\Delta E$), lattice constant, Seebeck coefficient, electrical conductivity, and power factor are systematically analyzed to determine the impact of doping on the material's properties. Our results show that doping with Li at the Mg site, Ga at the Si site, and F at the 4b site results in the most stable p-type Mg₂Si structure, with the lowest $\Delta E$ values. These dopants improve p-type conductivity and optimize the thermoelectric performance, particularly in the temperature range of 500–1000 K. The calculated transport properties reveal that Li- and F-doped Mg₂Si exhibit superior performance at high temperatures, making them promising candidates for thermoelectric applications. This research lays the groundwork for future experimental efforts to enhance the thermoelectric efficiency of p-type Mg₂Si.