Prepartion and characterisation of thermoelectric materials

Abstract

The polycrystalline samples of Mn50-xCoGa25+x and Ga50-xMnCo25+x have been prepared using Tri-Arc melting technique. The phase purity of the prepared samples is confirmed by powder x-ray diffraction measurements followed by Rietveld analysis. Transport properties of the samples have been studied at low temperature using four-probe method and magnetic measurements were done using a SQUID magnetometer. Metallic behavior and magnetic phase transition is observed in all the samples. The magnetic phase transition is shifted from 710 K to 163 K with varying concentration x. Our result will specify how the band structure at Fermi level is related to thermoelectric properties of the samples which may help in designing Mn, Co based thermoelectric material and spintronic devices.