Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
11006854 | Journal of Physics and Chemistry of Solids | 2018 | 29 Pages |
Abstract
First-principles calculations were performed to study the electronic and thermoelectric transport properties of Ca-substituted Sr3SnO (Sr3âxCaxSnO, 3â¯â¥â¯xâ¯â¥â¯0). The effects of Ca substitution on the bandgap are studied, and detailed mechanisms are proposed to explain the results obtained. We found that an increase of the hole concentration reduces the effective mass and the Seebeck coefficient of Ca-substituted Sr3SnO. The optimum hole concentration was obtained for Sr2CaSnO, and the corresponding maximum Seebeck coefficient of 219â¯Î¼V/K was obtained at 500â¯K. The electrical conductivity of Sr3SnO and its alloys has a semiconducting nature, which contradicts experimental results for Ca3SnO. We found that Ca-deficient Ca3SnO exhibits metallic conductivity, and this removes the contradiction with our results. The lattice thermal conductivities (κl) of Sr3SnO and Ca3SnO were calculated by use of both the Perdew-Burke-Ernzerhof functional and the GW functional. The total thermal conductivity for Sr3SnO and Ca3SnO at 300â¯K is 3.03 and 2.06â¯W/(m K), respectively. The figure of merit (ZT) for Sr2CaSnO at 500â¯K is 0.6, making it promising for thermoelectric applications.
Keywords
Related Topics
Physical Sciences and Engineering
Materials Science
Electronic, Optical and Magnetic Materials
Authors
Enamul Haque, M. Anwar Hossain,