Enhancement of thermoelectric properties by Se substitution in layered bismuth-chalcogenide LaOBiS2-xSex

TL;DR

This study explores how substituting selenium for sulfur in LaOBiS2-xSex enhances its thermoelectric properties, notably increasing electrical conductivity and power factor, with potential implications for thermoelectric applications.

Contribution

It demonstrates that Se substitution in LaOBiS2-xSex improves thermoelectric performance, providing new insights into material optimization.

Findings

Electrical conductivity increased with Se substitution.

Maximum power factor achieved was 4.5 μW/cmK^2 at 470°C.

ZT value reached 0.17 at 470°C for LaOBiS1.2Se0.8.

Abstract

We have investigated the thermoelectric properties of the novel layered bismuth chalcogenides LaOBiS2-xSex. The partial substitution of S by Se produced the enhancement of electrical conductivity (metallic characteristics) in LaOBiS2-xSex. The power factor largely increased with increasing Se concentration. The highest power factor was 4.5 uW/cmK2 at around 470 deg. C for LaOBiS1.2Se0.8. The obtained dimensionless figure-of-merit (ZT) was 0.17 at around 470 deg. C in LaOBiS1.2Se0.8.