Investigation of Oxide Thermoelectrics based on Indium and Tin

Abstract

Thermoelectric materials are those materials, which can directly converts a temperature difference into a useful electric energy. Looking forward to the applications of such a material, this project mainly aims at investigating naive Thermoelectric materials based on Indium and Tin. As part of the project, Indium based delafossites and Sn based perovskites where synthesized using solid state reactions and reactive flux method. The structural analysis was done by using powder XRD and SEM. The optical band gap for this materials were calculated from the Tauc’s plot and thermal conductivity is measured using TTO in PPMS. NaInO2 has the least thermal conductivity and optical band gap. After analysis we chose NaInO2 as the best candidate for further doping with aim to tune its properties for a Thermoelectric material. We doped the samples with hole and electron and studied the electronic and thermal conductivity of these samples. We found that 10% & 15% doped compounds could be good thermoelectrics at high temperatures. NaInO2, 10% & 15% doped compounds have very low thermal conductivity below room temperature, which is far less than the thermal conductivity of conventional thermoelectric materials.