Effect of the annealing treatment on structural and transport properties of thermoelectric Sm y(Fe x Ni1- x)4Sb12thin films

Giovanna Latronico; Paolo Mele; Chihiro Sekine; Pan Sian Wei; Saurabh Singh; Tsunehiro Takeuchi; Cédric Bourgès; Takahiro Baba; Takao Mori; Pietro Manfrinetti; Cristina Artini

doi:10.1088/1361-6528/aca980

Effect of the annealing treatment on structural and transport properties of thermoelectric Sm _y(Fe _x Ni_{1- x})4Sb₁₂thin films

Nanotechnology. 2023 Jan 4;34(11). doi: 10.1088/1361-6528/aca980.

Authors

Affiliations

¹ College of Engineering, Shibaura Institute of Technology, Omiya Campus, 307 Fukasaku, Minuma-ku, Saitama City, Saitama 337-8570, Japan.
² Muroran Institute of Technology, 27-1 Mitsumoto-cho, Muroran 050-8585, Hokkaido, Japan.
³ Toyota Technological Institute, 2-12-1 Hisakata Tenpaku, Nagoya 468-8511, Aichi, Japan.
⁴ International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), Namiki 1-1, Tsukuba 305-0044, Ibaraki, Japan.
⁵ Department of Chemistry and Industrial Chemistry, DCCI, - University of Genova, Via Dodecaneso 31, I-16146 Genova, Italy.
⁶ Institute of Condensed Matter Chemistry and Technologies for Energy, National Research Council, CNR-ICMATE, Via De Marini 6, I-16149 Genova, Italy.

PMID: 36595242
DOI: 10.1088/1361-6528/aca980

Abstract

The crystallographic and transport properties of thin films fabricated by pulsed laser deposition and belonging to the Sm_y(Fe_xNi_1-x)₄Sb₁₂filled skutterudite system were studied with the aim to unveil the effect exerted by temperature and duration of thermal treatments on structural and thermoelectric features. The importance of annealing treatments in Ar atmosphere up to 523 K was recognized, and the thermal treatment performed at 473 K for 3 h was selected as the most effective in improving the material properties. With respect to the corresponding bulk compositions, a significant enhancement in phase purity, as well as an increase in electrical conductivity and a drop in room temperature thermal conductivity, were observed in annealed films. The low thermal conductivity, in particular, can be deemed as deriving from the reduced dimensionality and the consequent substrate/film interfacial stress, coupled with the nanometric grain size.

Keywords: skutterudites; thermoelectric materials; thin films.