Defect induced structural and thermoelectric properties of Sb2Te3 alloy

TL;DR

This study investigates how defects in Sb2Te3 influence its structural and thermoelectric properties, revealing that higher defect densities enhance resistivity, thermopower, and power factor, with implications for thermoelectric applications.

Contribution

It provides new insights into the defect-induced variations in Sb2Te3's properties and discusses the impact of different scattering mechanisms on its thermoelectric performance.

Findings

Semiconducting Sb2Te3 has higher defect density than metallic samples.

Defects act as scattering centers, increasing resistivity and thermopower.

Surface states contribute to metallicity in Sb2Te3.

Abstract

Structural and thermoelectric properties of metallic and semiconducting Sb2Te3 are reported. X-Ray diffraction and Raman spectroscopy studies reveal that semiconducting sample have higher defect density. Nature and origin of possible defects are highlighted. Semiconducting Sb2Te3 hosts larger numbers of defects, which act as scattering center and give rise to the increased value of resistivity, thermopower and power factor. Thermopower data indicates p-type nature of the synthesized samples. It is evidenced that the surface states are often mixed with the bulk state, giving rise to metallicity in Sb2Te3. Role of different scattering mechanism on the thermoelectric property of Sb2Te3 is discussed.