Journal
CHEMISTRY OF MATERIALS
Volume 34, Issue 3, Pages 1289-1301Publisher
AMER CHEMICAL SOC
DOI: 10.1021/acs.chemmater.1c03987
Keywords
-
Funding
- U.S. Department of Energy, Office of Science [DE-SC0014520]
- U.S. Department of Energy, Office of Basic Energy Sciences [DE-SC0014520]
- National Institute of Standards and Technology as part of the Center for Hierarchical Materials Design (CHiMaD) [70NANB14H012]
- U.S. Department of Commerce as part of the Center for Hierarchical Materials Design (CHiMaD) [70NANB14H012]
- National Key Research and Development Program of China [2019YFA0704902]
- National Natural Science Foundation of China [51972256, 51872219, 51632006, 51521001]
- 111 Project of China [B07040]
- China Scholarship Council at the Northwestern University [201906950054]
Ask authors/readers for more resources
By introducing weak-bonding elements Ba or Sr into the SnS2 framework, two SnS2-based materials BaSnS3 and SrSnS3 with low thermal conductivity and high carrier mobility were discovered, showing potential for high-performance thermoelectric applications.
SnS2, an earth-abundant and ecofriendly material, is limited as a thermoelectric material because of the high lattice thermal conductivity kappa(L) and low carrier mobility mu. By introducing weak-bonding elements Ba or Sr into the SnS2 framework, we discovered two SnS2-based materials BaSnS3 and SrSnS3 with the calculated low kappa(L) values of 0.15 and 0.17 W m(-1) K-1, respectively, along the a-axis. The low group velocity and high lattice anharmonicity originating from the weakened and distorted Sn-S bonding network are found in both systems. Moreover, the vibrations of Ba and Sr induce low-lying optical phonons, which strongly couple with the acoustic phonons and strengthen the phonon scattering rates. Compared to SnS2, both compounds present lower single-band effective masses, smaller deformation potential constants, and better band convergence, which enhance mu with an insignificantly reduced effective mass. By solving the linearized Boltzmann transport equation with a nonempirical carrier lifetime, we predict excellent ZT values of 2.89 and 2.77 along the a-axis at 900 K in BaSnS3 and SrSnS3, respectively. Further phase diagram calculations of Ba1-xSrxSnS3 solid solutions propose a new compound, Ba0.5Sr0.5SnS3, with an even higher ZT of 3.0. Our work analyzes explicitly how weak-bonding elements enhance mu and suppress kappa(L) simultaneously in SnS2-analogous systems with a series of compounds nominated as potential high-performance thermoelectric materials.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available