Abstract
As a traditional thermoelectric material with high thermoelectric performance at room temperature, antimony telluride (Sb2Te3) has been widely used in energy applications like power generation and refrigeration. By employing the "atomic transmutation" method, three new kinds of Sb2Te3-based monolayers of α-Sb2Te2Se, α-Sb2TeSe2, and β-Sb2TeSe2 are designed, which are expected to possess a high thermoelectric performance due to the quantum-confinement effects. In this work, by using the ab initio calculations, we systematically study electronic structures, vibration modes, optical, transport, and thermoelectric properties for the three kinds of monolayers and find that they are indirect-band-gap semiconductor materials with chemical and thermodynamic stability up to 700 K (α-Sb2TeSe2) or 900 K (α-Sb2Te2Se and β-Sb2TeSe2). The band gaps are around 1.0 eV with five nearly degenerate peaks in valence bands. The three Sb2Te3-xSex monolayers possess high electron mobilities larger than 1000 cm2/(V s), and the maximum zT values of α-Sb2Te2Se/α-Sb2TeSe2/β-Sb2TeSe2 are 0.70/0.71/0.65 at 300 K, respectively. For optical properties, the three Sb2Te3-xSex monolayers possess a wide absorption range from the blue region to the ultraviolet region. Compared with Sb2Te3, the three new kinds of monolayers possess a wider range of absorptions, higher mobilities, and thermoelectric performances, which may lead to promising applications in thermoelectric devices and saturable absorbers.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.