RESEARCH OF SENSITIVE ELEMENTS OF THERMOELECTRIC CONVERTERS BASED ON Hf1-xNbxNiSn

The results of modeling and experimental studies of the structural, magnetic, electrokinetic and energy properties of the thermometric material Hf1-xNbxNiSn, as well as the conversion functions of the sensitive elements of a thermoelectric thermometer based on it at temperatures of 4.2–1000 K are presented. For the case of an ordered variant of the crystal structure of the thermometric material, the simultaneous generation of donor and acceptor states in the forbidden band εg of the semiconductor is established. The dependence between the spatial arrangement of atoms in the nodes of the Hf1-xNbxNiSn unit cell and the mechanisms of electrical conductivity is revealed, which allows us to determine the conditions for the synthesis of materials with the maximum efficiency of converting thermal energy into electrical energy. It is shown that at Hf1-xNbxNiSn concentrations, x=0–0.02, the substitution of Hf atoms (5d26s2) by Nb atoms (4d45s1) in position 4a mainly occurs, which generates donor states. In the concentration range Hf1- xNbxNiSn, x=0.02–0.05, the substitution of Ni atoms (3d84s2) in position 4a by Nb atoms mainly occurs, which generates acceptor states, and at concentrations 0.05