elib
DLR-Header
DLR-Logo -> http://www.dlr.de
DLR Portal Home | Impressum | Datenschutz | Kontakt | English
Schriftgröße: [-] Text [+]

On the relevance of point defects for the selection of contacting electrodes: Ag as an example for Mg2(Si,Sn)-based thermoelectric generators

Ayachi, Sahar und Deshpande, Radhika und Ponnusamy, Prasanna und Park, Sungjin und Ryu, Byungki und Müller, Eckhard und de Boor, Johannes (2020) On the relevance of point defects for the selection of contacting electrodes: Ag as an example for Mg2(Si,Sn)-based thermoelectric generators. Materials Today Physics. Elsevier. doi: 10.1016/j.mtphys.2020.100309. ISSN 2542-5293.

[img] PDF - Preprintversion (eingereichte Entwurfsversion)
799kB

Kurzfassung

In developing thermoelectric generators, optimizing interfaces between thermoelectric materials and contacting electrodes is a crucial step. Among the tested electrodes for Mg2(Si,Sn)-based generators, Ag shows good adhesion, controllable interfaces and low electrical contact resistances. However, it induces unexpected changes in the Seebeck coefficient of n-type samples, while no change is observed in p-type. In order to understand said behavior, contacting results for Bi-doped Mg2Si, Mg2Sn and Mg2Si1-xSnx with Ag are compared with predictions based on defect formation energies obtained within hybrid-density functional theory (DFT). A qualitative description of the Ag diffusion mechanism in Mg2X is also introduced. Calculation results show that Ag-induced defects have sufficiently low formation energies to influence charge carrier concentrations, particularly Ag substitution on the Mg site (AgMg). AgMg acts as an acceptor and causes a counter-doping effect by compensating the electrons provided by Bi. However, in Li-doped p-type, as Li-defects have the lowest formation energies, a negligible charge carrier concentration change is predicted, which fits with experimental observations. Concerning solid solutions, interpolation from the binaries predicts a similar behavior, which also meets experimental findings. Therefore, this work not only establishes the calculation method and explains the observed effect, but also proves the importance of defects in selecting contacting electrodes.

elib-URL des Eintrags:https://elib.dlr.de/137155/
Dokumentart:Zeitschriftenbeitrag
Titel:On the relevance of point defects for the selection of contacting electrodes: Ag as an example for Mg2(Si,Sn)-based thermoelectric generators
Autoren:
AutorenInstitution oder E-Mail-AdresseAutoren-ORCID-iDORCID Put Code
Ayachi, SaharGerman aerospace center, institute of materials research, köln, germanyNICHT SPEZIFIZIERTNICHT SPEZIFIZIERT
Deshpande, RadhikaGerman aerospace center, institute of materials research, köln, germanyNICHT SPEZIFIZIERTNICHT SPEZIFIZIERT
Ponnusamy, Prasannagerman aerospace center, institute of materials research, köln, germanyNICHT SPEZIFIZIERTNICHT SPEZIFIZIERT
Park, SungjinEnergy Conversion Research Center, Electrical Materials Research Division, Korea Electrotechnology Research Institute (KERI), Changwon, KoreaNICHT SPEZIFIZIERTNICHT SPEZIFIZIERT
Ryu, ByungkiEnergy Conversion Research Center, Electrical Materials Research Division, Korea Electrotechnology Research Institute (KERI), Changwon, KoreaNICHT SPEZIFIZIERTNICHT SPEZIFIZIERT
Müller, Eckhardgerman aerospace center, institute of materials research, köln, germany and justus liebig university giessen, institute of inorganic and analytical chemistry, 35392 giessen, germanyNICHT SPEZIFIZIERTNICHT SPEZIFIZIERT
de Boor, JohannesGerman aerospace center, institute of materials research, köln, germanyhttps://orcid.org/0000-0002-1868-3167NICHT SPEZIFIZIERT
Datum:31 Oktober 2020
Erschienen in:Materials Today Physics
Referierte Publikation:Ja
Open Access:Ja
Gold Open Access:Nein
In SCOPUS:Ja
In ISI Web of Science:Ja
DOI:10.1016/j.mtphys.2020.100309
Verlag:Elsevier
ISSN:2542-5293
Status:veröffentlicht
Stichwörter:Defects; Contacting electrodes; Ag, Mg2(Si,Sn), Thermoelectric
HGF - Forschungsbereich:Luftfahrt, Raumfahrt und Verkehr
HGF - Programm:Raumfahrt
HGF - Programmthema:Technik für Raumfahrtsysteme
DLR - Schwerpunkt:Raumfahrt
DLR - Forschungsgebiet:R SY - Technik für Raumfahrtsysteme
DLR - Teilgebiet (Projekt, Vorhaben):R - Systemtechnologien (alt)
Standort: Köln-Porz
Institute & Einrichtungen:Institut für Werkstoff-Forschung > Thermoelektrische Materialien und Systeme
Hinterlegt von: Frank, Adina
Hinterlegt am:06 Nov 2020 10:23
Letzte Änderung:23 Okt 2023 14:08

Nur für Mitarbeiter des Archivs: Kontrollseite des Eintrags

Blättern
Suchen
Hilfe & Kontakt
Informationen
electronic library verwendet EPrints 3.3.12
Gestaltung Webseite und Datenbank: Copyright © Deutsches Zentrum für Luft- und Raumfahrt (DLR). Alle Rechte vorbehalten.