Modulating the thermoelectric transport properties of the novel material Er2Te3 via strain

The rare-earth chalcogenide Er2Te3, characterized by its low lattice thermal conductivity, represents a highly promising and innovative thermoelectric material. However, there have been limited studies exploring its thermoelectric properties in depth. Additionally, it has been discovered that strain engineering is an effective method for enhancing thermoelectric properties, a technique successfully applied to relevant materials. In this study, we employed a first-principles approach in conjunction with the semi-classical Boltzmann transport theory to investigate the thermoelectric properties of Er2Te3 materials under -4% to 4% strain. The results indicate that applying compressive strain modulates thermoelectric properties more effectively than tensile strain for Er2Te3. Under strain modulation, the maximum power factor for both p-type and n-type Er2Te3 increases significantly, from 0.9 to 2.5 mW m(-1) K-2 and from 14 to 18 mW m(-1) K-2 at 300 K, respectively. Moreover, the figure of merit (ZT) for p-type and n-type Er2Te3 improves notably, from 0.15 to 0.25 and from 1.15 to 1.35, respectively, under -4% strain. Consequently, the thermoelectric properties of Er2Te3 materials can be significantly enhanced through strain application, with n-type Er2Te3 demonstrating substantial potential as a thermoelectric material.