Published in

Royal Society of Chemistry, Journal of Materials Chemistry C Materials for optical and electronic devices, 12(4), p. 2329-2338, 2016

DOI: 10.1039/c5tc04267d

Links

Tools

Export citation

Search in Google Scholar

High thermoelectric performance in Sn-substituted α-As2Te3

This paper is available in a repository.
This paper is available in a repository.

Full text: Download

Green circle
Preprint: archiving allowed
Orange circle
Postprint: archiving restricted
Red circle
Published version: archiving forbidden
Data provided by SHERPA/RoMEO

Abstract

Lead chalcogenides PbX (X = Te, Se, S) have been the materials of choice for thermoelectric power generation at mid-range temperatures (500 – 700 K). Here, we report on a new family of chalcogenides α-As2Te3 that exhibits similar thermoelectric performances near 500 K. Sn doping in p-type polycrystalline α-As2-xSnxTe3 (x ≤ 0.075) provides an efficient control parameter to tune the carrier concentration leading to thermopower values that exceed 300 μV K-1 at 500 K. Combined with the structural complexity of the monoclinic lattice that results in extremely low thermal conductivity (0.55 W m-1 K-1 at 523 K), a peak ZT value of 0.8 is achieved at 523 K for x = 0.05. A single-parabolic band model is found to capture well the variations in the transport properties with the Sn concentration and suggests that higher ZT values could be achieved through band structure engineering. These results surpass those obtained in the sister compounds β-As2-xSnxTe3 and further show that α-As2Te3 based materials are competitive with other chalcogenides for thermoelectric applications at intermediate temperatures.