Ternary mixed-anion semiconductors with tunable band gaps from machine-learning and crystal structure prediction
Year: 2019
Type: article
Abstract: We report the computational investigation of a series of ternary ${X}_{4}{Y}_{2}Z$ and ${X}_{5}{Y}_{2}{Z}_{2}$ compounds with $X$=Mg, Ca, Sr, Ba; $Y$=P, As, Sb, Bi; and $Z$=S, Se, Te. The compositions for these materials were predicted through a search guided by machine learning, while the structures were resolved using the minima hopping crystal structure prediction method. Based on ab initio calculations, we predict that many of these phases are thermodynamically stable. In particular, 21 of the ${X}_{4}{Y}_{2}Z$ compounds crystallize in a tetragonal structure with $I\overline{4}2d$ symmetry, and exhibit band gaps in the range of 0.8 and 1.8 eV, well suited for various energy applications. We show that several candidates (in particular ${X}_{4}{Y}_{2}\mathrm{Te}$ and ${X}_{4}{\mathrm{Sb}}_{2}\mathrm{Se}$) exhibit good photo absorption in the visible range, while others (e.g., ${\mathrm{Ba}}_{4}{\mathrm{Sb}}_{2}\mathrm{Se}$) show excellent thermoelectric performance due to high power factors and extremely low lattice thermal conductivities.
Source: Physical Review Materials
Authors: Maximilian Amsler, Logan Ward, Vinay I. Hegde, Maarten G. Goesten, Xia Yi, Chris Wolverton
Institutions: Cornell University, Northwestern University
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: green
Funders: National Science Foundation, U.S. Department of Energy, U.S. Department of Commerce, Northwestern University, Universität Basel, Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung, Nederlandse Organisatie voor Wetenschappelijk Onderzoek, National Institute of Standards and Technology, Materials Research Science and Engineering Center, Harvard University, National Supercomputing Center, Korea Institute of Science and Technology Information, Division of Materials Research, Center for Hierarchical Materials Design
Awards: G1169090945, G1286236842, G1314375578, G1676583131, G1863003419, G2517729222, G3059599288, G3295719173, G3967535168, G4285583887, G4289625387, G42916606, G4361631179, MRSEC: Center for Multifunctional Materials, G4778125835, G4796240486, G4912152698, G5218300437, Improved methods for theoretical materials design, ADVANCED MATERIALS CENTER OF EXCELLENCE, Improved methods for theoretical materials design, XSEDE: eXtreme Science and Engineering Discovery Environment, Bridges: From Communities and Data to Workflows and Insight
OpenAlex ID: W2902866852