2, Jet Propulsion Laboratory, Pasadena, California, United States
Thermoelectric (TE) power generation is the direct conversion of thermal energy into electrical work. The search for novel TE materials is necessary in the pursuit of higher efficiency TE devices. Layered tetrel pnictides have shown promise as TEs due to their anisotropic crystal structure and weak van der Waals interactions between the layers. The binary GeAs is a p-type semiconductor with a narrow indirect bandgap of 0.57eV and high Seebeck coefficient (~250 µV/K at 300 K). The main drawback of this compound is its poor electrical conductivity due to the relatively low charge carrier concentration. This work investigates the aliovalent doping of the Ge and As sublattice in the GeAs structure. The synthesis, structure, and transport properties of Ga- and Se-doped GeAs will be discussed.