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

The rare-earth chalcogenide Er ₂Te ₃ 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 Er ₂Te ₃ 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 Er ₂Te ₃ at 300 K increases to approximately 1.8 mW·m ⁻¹·K ⁻², while n-type Er ₂Te ₃ 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 Er ₂Te ₃ material to 0.3 at 300 K and n-type Er ₂Te ₃ material to 1.35 when subjecting the n-type Er ₂Te _2.82Po _0.18 system to a −2% strain. These results suggest that even minor doping can yield similar enhancements in the thermoelectric performance of Er ₂Te ₃, 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 Er ₂Te ₃ 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.