Computational prediction of high thermoelectric performance in As₂Se₃ by engineering out-of-equilibrium defects

Author(s)

Chaves, Anderson Silva ; Silva, Murilo Aguiar ; Antonelli, Alex

• Document type: Journal article
• Source: Physical Chemistry Chemical Physics; v. 26, n. 5, p. 7-pg., 2024-01-09.

Abstract

We employed first-principles calculations to investigate the thermoelectric transport properties of the compound As2Se3. Early experiments and calculations have indicated that these properties are controlled by a kind of native defect called antisites. Our calculations using the linearized Boltzmann transport equation within the relaxation time approximation show good agreement with the experiments for defect concentrations of the order of 10(19) cm(-3). Based on our total energy calculations, we estimated the equilibrium concentration of antisite defects to be about 10(14) cm(-3). These results suggest that the large concentration of defects in the experiments is due to kinetic and/or off-stoichiometry effects and in principle it could be lowered, yielding relaxation times similar to those found in other chalcogenide compounds. In this case, for relaxation time higher than 10 fs, we obtained high thermoelectric figures of merit of 3 for the p-type material and 2 for the n-type one. (AU)

• FAPESP's process: 17/26105-4 - Multi-user equipment approved in grant 2016/23891-6 high performace computational cluster
• Grantee: Alex Antonelli
• Support Opportunities: Multi-user Equipment Program
• FAPESP's process: 15/26434-2 - Study of the electronic, structural, and transport properties of materials for thermoelectric applications via ab initio calculations
• Grantee: Anderson Silva Chaves
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 16/23891-6 - Computer modeling of condensed matter
• Grantee: Alex Antonelli
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 19/26088-8 - Study of doping effects in As2Se3 and As2S3 from first-principles calculations
• Grantee: Anderson Silva Chaves
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 10/16970-0 - Computational modeling of condensed matter: a multiscale approach
• Grantee: Alex Antonelli
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 13/08293-7 - CCES - Center for Computational Engineering and Sciences
• Grantee: Munir Salomao Skaf
• Support Opportunities: Research Grants - Research, Innovation and Dissemination Centers - RIDC