Thermoelectric Properties of Intermetallic Semiconducting RuIn3 and Metallic IrIn3

TL;DR

This study investigates the thermoelectric properties of RuIn3 and IrIn3, revealing that iridium substitution significantly enhances thermoelectric efficiency, with potential implications for low-temperature thermoelectric applications.

Contribution

It demonstrates how iridium substitution in RuIn3 improves thermoelectric performance, providing new insights into material optimization for thermoelectric devices.

Findings

RuIn3 has a large Seebeck coefficient but low ZT due to high resistivity.

IrIn3 is metallic with low thermopower at room temperature.

Iridium substitution enhances ZT from 0.007 to 0.053 at 380 K.

Abstract

Low temperature (<400 K) thermoelectric properties of semiconducting RuIn3 and metallic IrIn3 are reported. RuIn3 is a narrow band gap semiconductor with a large n-type Seebeck coefficient at room temperature (S(290K)~400 {\mu}V/K), but the thermoelectric Figure of merit (ZT(290K) = 0.007) is small because of high electrical resistivity and thermal conductivity ({\kappa}(290 K) ~ 2.0 W/m K). IrIn3 is a metal with low thermopower at room temperature (S(290K)~20 {\mu}V/K) . Iridium substitution on the ruthenium site has a dramatic effect on transport properties, which leads to a large improvement in the power factor and corresponding Figure of merit (ZT(380 K) = 0.053), improving the efficiency of the material by an over of magnitude.