Thermal, electro-magnetic and thermoelectric investigation of CoNb1-xTixSn (x = 0, 0.75, 0.5, 1) half-Heusler alloy

Abstract

In this work, structural, thermal, electro-magnetic and thermoelectric attributes of CoNb1-xTixSn (x = 0, 0.75, 0.5, 0.25, 0) alloys have been investigated using density functional theory (DFT). The structural reforms, brought to CoNbSn, portray the increase in its rigidity when increasing the Ti content substituted at the Nb site. They also remodel the character of the alloy from semiconducting paramagnetic to half-metallic ferromagnetic nature. By investigating elastic properties that are interlinked with structural optimizations and enthalpy of formation, studied alloys displayed stable structure. Thermoelectric properties such as Seebeck coefficient (S), electrical conductivity (σ/τ) and power factor (S 2 σ/τ), are calculated based on the Boltzmann transport theory. Results revealed that for x = 0.75 in CoNb1-xTixSn, a temperature dependent switch from n-type to p-type is observed. According to the results obtained, CoNb1-xTixSn alloys could have potential thermoelectric applications.