Synergistic regulation of sulfur-group elements doping and strain on the thermoelectric performance of innovative material Er2Te3

Abstract

The rare-earth chalcogenide Er2Te3 exhibits substantial promise as an innovative thermoelectric material. However, there have been limited studies exploring its thermoelectric properties in depth. Our study employed a first-principles approach in conjunction with the semi-classical Boltzmann transport theory to investigate the collaborative modulation of the thermoelectric transport properties of Er2Te3 through the concurrent application of sulfur-group elements doping and strain engineering. The findings demonstrate that, in the presence of the synergistic interplay of doping and strain, the maximum power factor (PF) of p-type Er2Te3 at 300 K increases to approximately 1.8 mW·m−1·K−2, while n-type Er2Te3 is elevated to approximately 18 mW·m−1·K−2. Furthermore, the cooperative effects of doping and strain augmentation raise the optimal thermoelectric figure of merit (ZT) of p-type Er2Te3 material to 0.3 at 300 K and n-type Er2Te3 material to 1.35 when subjecting the n-type Er2Te2.82Po0.18 system to a −2% strain. These results suggest that even minor doping can yield similar enhancements in the thermoelectric performance of Er2Te3, particularly under conditions of smaller strain. Consequently, our work underscores the significance of synergistic interactions between doping and strain engineering as potent means to augment the thermoelectric performance of Er2Te3 materials. In light of the practical feasibility of the fabrication techniques employed, this novel rare-earth chalcogenide material warrants further scrutiny and subsequent exploration within experimental domains.