Research of Thermoelectric Material Ti1-xNbxNiSn
DOI:
https://doi.org/10.63527/1607-8829-2025-1-5-15Keywords:
thermoelectric material, thermoelectric figure of merit, electronic structure, electrical resistivity, thermopower coefficientAbstract
The structural, kinetic, energetic, and magnetic properties of the semiconductor thermoelectric material Ti1-xNbxNiSn, obtained by doping n-TiNiSn with Nb atoms, have been studied. It has been shown that Nb atoms (4d45s1) simultaneously occupy different crystallographic positions, generating structural defects of donor and acceptor nature. At Ti1-xNbxNiSn concentrations, х=0–0.04, Nb atoms predominantly replace Ti (3d24s2) and Ni (3d84s2) atoms present there in position 4a, generating donor and acceptor states in the band gap εg, respectively. At higher concentrations, х˃0.04, Nb atoms replace only Ti atoms, generating structural defects and energetic states of donor nature. It is shown that the semiconducting solid solution Ti1-xNbxNiSn is a promising thermoelectric material, and at T≈650 K and Ti0.99Nb0.01NiSn concentration ZT is equal to 0.76. The studies allowed us to identify the mechanisms of electrical conductivity to determine the conditions for the synthesis of thermoelectric materials Ti1-xNbxNiSn with maximum efficiency of converting thermal energy into electrical energy.
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