Features of microstructure and thermoelectric properties of the cermet composites based on grained Bi2Te3 matrix with locally-gradient Ni@NiTe2 inclusions

Starting Bi2Te3 and Ni powders were spark-plasma-sintered (SPS) to prepare thermoelectric cermet composites consisting of matrix with different content, x, ferromagnetic filler (x = 0.00, 0.50, 0.85, 1.25 1.50 at. %). Grained is texturing under sintering. Texturing degree x-dependent that attributed ability particles act as lubricant. New trigonal NiTe2 phase formed SPS-process. The phases correspond [email protected]2 (“core”-“shell”) inclusions. Forming these inclusions originated from chemical interaction between during A Ni→NiTe2 reaction accelerated increasing x results in growing fraction shell. Thermoelectric properties are due non-monotonic changes degree, size the concentration majority carriers x. figure-of-merit remarkably enhancing compared matrix.