Thermoelectric properties of ternary transition metal antimonides

摘要

Novel compounds T_6Mbi_2, where T=Zr, Hf;M=Fe, Co, Ni, were synthesised by arc melting elementalcombinations. Isotypism of these compounds with the orderedFe_2P-type was established from Rietveld X-ray powder data.Physical properties (electrical resistivity and thermoelectric power)were investigated for a series of ternary transition metalcompounds with stoichiometries such as TM_(1-x)X andT_6MX_2,where T is an electropositive transition metal (Zr, Hfand Nb), M is a metal from the iron group (Fe, Co, Ni) and X is Sbor Bi. Resistivities reveal a general metallic behaviour except forZrCoSb and NbFeSb which are characterized by variable rangehopping conductivity in a substantial temperature region.Thermoelectric power of these materials does not exceed 100 #mu#V K~(-1).