title: Thermoelectric properties and electronic structure of the Zintl phase Sr₅In₂Sb₆ and the Ca(5-x)Sr(x)In₂Sb₆ solid solution.
abstract: The Zintl phase Sr5In2Sb6 is isostructural with Ca5In2Sb6-a promising thermoelectric material with a peak zT of 0.7 when the carrier concentration is optimized by doping. Density functional calculations for Sr5In2Sb6 reveal a decreased energy gap and decreased valence band effective mass relative to the Ca analog. Chemical bonding analysis using the electron localizability indicator was found to support the Zintl bonding scheme for this structure type. High temperature transport measurements of the complete Ca(5-x)Sr(x)In2Sb6 solid solution were used to investigate the influence of the cation site on the electronic and thermal properties of A5In2Sb6 compounds. Sr was shown to be fully miscible on the Ca site. The higher density of the Sr analog leads to a slight reduction in lattice thermal conductivity relative to Ca5In2Sb6, and, as expected, the solid solution samples have significantly reduced lattice thermal conductivities relative to the end member compounds.
authors.affiliation: Department of Applied Physics and Materials Science, California Institute of Technology, 1200 E California Blvd, Pasadena, CA, USA. Thermal Energy Conversion Technologies Group, Jet Propulsion Laboratory, 4800 Oak Grove Drive, Pasadena, CA, USA.
authors.forename: Alex
authors.initials: A
authors.lastname: Zevalkink
authors.forename: Sevan
authors.initials: S
authors.lastname: Chanakian
authors.forename: Umut
authors.initials: U
authors.lastname: Aydemir
authors.forename: Alim
authors.initials: A
authors.lastname: Ormeci
authors.forename: Gregory
authors.initials: G
authors.lastname: Pomrehn
authors.forename: Sabah
authors.initials: S
authors.lastname: Bux
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Fleurial
authors.forename: G Jeffrey
authors.initials: GJ
authors.lastname: Snyder