title: Role of Nanostructuring and Microstructuring in Silver Antimony Telluride Compounds for Thermoelectric Applications.
abstract: Thermoelectric (TE) materials are of utmost significance for conversion of heat flux into electrical power in the low-power regime. Their conversion efficiency depends strongly on the microstructure. AgSbTe2-based compounds are high-efficiency TE materials suitable for the mid-temperature range. Herein, we explore an Ag16.7Sb30Te53.3alloy (at %) subjected to heat treatments at 380 °C for different durations aimed at nucleation and coarsening of Sb2Te3-precipitates. To characterize the Sb2Te3-precipitation, we use a set of methods combining thermal and electrical measurements in concert with transmission electron microscopy and atom probe tomography. We find correlations between the measured TE transport coefficients and the applied heat treatments. Specifically, the lowest electrical and thermal conductivity values are obtained for the as-quenched state, whereas the highest values are observed for alloys aged for 8 h. In turn, long-term heat treatments result in intermediate values of transport coefficients. We explain these findings in terms of interplay between precipitate formation and variations in the matrix composition, highlighting the importance of thermal stability of the material under service conditions.
authors.affiliation: I. Institut of Physics, RWTH Aachen University , Sommerfeldstraße 14, 52056 Aachen, Germany.|Max-Planck Institut für Eisenforschung GmbH , Max-Planck Straße 1, D-40237 Düsseldorf, Germany.
authors.forename: Oana
authors.identifier: http://orcid.org/0000-0001-6543-203X
authors.initials: O
authors.lastname: Cojocaru-Mirédin
authors.affiliation: Max-Planck Institut für Eisenforschung GmbH , Max-Planck Straße 1, D-40237 Düsseldorf, Germany.
authors.forename: Lamya
authors.initials: L
authors.lastname: Abdellaoui
authors.affiliation: Department of Materials Science and Engineering, Technion-Israel Institute of Technology , Technion City, 32000 Haifa, Israel.
authors.forename: Michael
authors.identifier: http://orcid.org/0000-0001-9807-3432
authors.initials: M
authors.lastname: Nagli
authors.affiliation: Max-Planck Institut für Eisenforschung GmbH , Max-Planck Straße 1, D-40237 Düsseldorf, Germany.
authors.forename: Siyuan
authors.initials: S
authors.lastname: Zhang
authors.affiliation: I. Institut of Physics, RWTH Aachen University , Sommerfeldstraße 14, 52056 Aachen, Germany.
authors.forename: Yuan
authors.identifier: http://orcid.org/0000-0002-3148-6600
authors.initials: Y
authors.lastname: Yu
authors.affiliation: Max-Planck Institut für Eisenforschung GmbH , Max-Planck Straße 1, D-40237 Düsseldorf, Germany.|Materials Analytics, RWTH Aachen University , Kopernikusstraße 10, 52074 Aachen, Germany.
authors.forename: Christina
authors.identifier: http://orcid.org/0000-0001-7916-1533
authors.initials: C
authors.lastname: Scheu
authors.affiliation: Max-Planck Institut für Eisenforschung GmbH , Max-Planck Straße 1, D-40237 Düsseldorf, Germany.
authors.forename: Dierk
authors.initials: D
authors.lastname: Raabe
authors.affiliation: I. Institut of Physics, RWTH Aachen University , Sommerfeldstraße 14, 52056 Aachen, Germany.
authors.forename: Matthias
authors.identifier: http://orcid.org/0000-0003-1498-1025
authors.initials: M
authors.lastname: Wuttig
authors.affiliation: Department of Materials Science and Engineering, Technion-Israel Institute of Technology , Technion City, 32000 Haifa, Israel.
authors.forename: Yaron
authors.initials: Y
authors.lastname: Amouyal
keywords: atom probe tomography; electron microscopy; silver−antimony−telluride compounds; thermal conductivity; thermoelectric materials