Thermoelectric performance and the role of anti-site disorder in the 24-electron Heusler TiFe₂Sn

Abstract

Abstract. Heusler compounds XY 2 Z with 24 valence electrons per formula unit are potential thermoelectric materials, given their thermal and chemical stability and their relatively earth-abundant constituent elements. First principal calculations on this compound suggest semiconducting behavior of TiFe 2 Sn, and a relatively flat conduction band that could be associated with a high Seebeck coefficient upon electron doping. TiFe 2 Sn as a thermoelectric material has been studied via synchrotron Xray and neutron diffraction studies that characterize site order/disorder phenomena. Samples fabricated by a three step processing approach were subjected to high temperature Seebeck and electrical resistivity measurements. Ti:Fe anti-site disorder is present in the stoichiometric compound and these defects are reduced in Ti-rich compositions. Additionally, we investigate control of the Seebeck coefficient through the introduction of carriers through the substitution of Sb on the Sn site in these intrinsically p-type materials. Thermoelectric performance in Heusler TiFe

Decisive role of interstitial defects in half-Heusler semiconductors: An ab initio study

“…Our calculations using equations ( 1 the above Ni-and Co-based alloys, are more likely to occupy vacant interstitial sites. Our study of intrinsic point defects for the half-Heusler alloys can also be interesting in the context of full-Heusler thermoelectric materials for which such defects are found to play decisive role in determining their thermoelectric performance [76][77][78][79].…”

Unconventional Materials: the mismatch between electronic charge centers and atomic positions

“…The results in SM show that the essential BR is A g @16d for Al 2 Ru/Ga 2 Ru, A g @2b for In 3 Ru and A g @24d for TiFe 2 Sn/AlVFe 2 /VGaFe 2 . Thermoelectric properties, superparamagnetism and negative giant magnetoresistance have been widely studied in the Heusler compounds XY 2 Z with 24 valence electrons [39,[41][42][43].…”

Влияние легирования ванадием на термоэлектрические свойства сплавов Гейслера Fe-=SUB=-2-=/SUB=-Ti-=SUB=-1-x-=/SUB=-V-=SUB=-x-=/SUB=-Sn

“…4 приведена температурная зависимость коэффициента термоэдс, измеренная в нашей работе; для сравнения показаны также результаты измерений термоэдс, опубликованные в работах других научных групп. Из сравнения этих данных видно, что результаты наших измерений хорошо коррелируют с исследованиями, опубликованными в работах [10][11][12].…”