High Thermoelectric Performance of Au@Sb2Te3 Heterostructure Derived from the Potential Barriers

TL;DR

This paper demonstrates that embedding Au nanostructures in Sb2Te3 enhances thermoelectric performance by increasing electrical conductivity and Seebeck coefficient while reducing thermal conductivity, leading to doubled ZT values.

Contribution

It introduces a novel Au@Sb2Te3 heterostructure that simultaneously improves electrical and thermal properties for better thermoelectric efficiency.

Findings

Electrical conductivity increased due to Au nanostructures injecting carriers.

Seebeck coefficient enhanced by energy filtering at Au-Sb2Te3 interfaces.

Thermal conductivity reduced by increased boundaries and nanodomains.

Abstract

The correlated couple of electrical and thermal property is the challenge to realize a substantial leap in thermoelectric materials.Synthesis of semiconductor and metal composites is a significant and versatile design strategy to optimize the thermoelectric performance driven by tailored interface between nanoinclusions and matrix.In this study, we present the simultaneous increase of electrical conductivity and Seebeck coefficient, and reduction of thermal conductivity in Sb2Te3-Au system.The enhanced electrical conductivity lies in the incorporated Au nanostructures contributing to injecting carriers to Sb2Te3 matrix.The appropriate barriers originated from the Au-Sb2Te3 interface, which filter low energy carriers, results in enhancement of Seebeck coefficient.The increased boundaries and nanodomains block the transport of phonons, subsequently reducing the thermal conductivity.As a consequence, combination of these effects promote double of ZT value in 1% Au@ Sb2Te3 composites with respect to the pristine Sb2Te3.