Multilayered thin films for oxidation protection of Mg2Si thermoelectric material at middle-high temperatures

Multilayered molybdenum silicide-based thin films were deposited via radio frequency magnetron sputtering in order to obtain efficient barrier against oxidation process which affected Mg2Si thermoelectric materials at middle-high temperatures. X ray diffraction, energy dispersive spectroscopy, secondary ion mass spectroscopy, field emission scanning electron microscopy (FE-SEM) and electrical measurements at high temperature were carried out in order to obtain, respectively, the structural, compositional, morphological and electrical characterization of coatings. Furthermore, the mechanical behavior of the thin film/Mg2Si-pellet system was observed in situ as a function of temperature by FE-SEM employing a heating module. Moreover, the barrier properties for oxygen protection after thermal treatment in air at high temperature were qualitatively evaluated.