Enhancement of thermoelectric power of PbTe:Ag nanocomposite thin films

Autor: Shikha Varma, Srashti Gupta, K. Asokan, Manju Bala, Surya Kant Tripathi, D.K. Avasthi, T. S. Tripathi
Rok vydání: 2015
Předmět:
Zdroj: RSC Advances. 5:25887-25895
ISSN: 2046-2069
DOI: 10.1039/c5ra01000d
Popis: The present study focuses on the enhancement of thermoelectric power of PbTe:Ag nanocomposite thin films, synthesized by the thermal evaporation technique. Thermoelectric measurements were carried out from room temperature to 400 K. It is observed that Ag addition improves the thermoelectric power and crystalline nature of the PbTe thin films. Synchrotron based X-ray diffraction was performed to confirm the phases of the Pb–Ag–Te alloy. This was further reconfirmed by X-ray photoelectron spectroscopy (XPS) and showed the precipitation of Pb on the surface of the PbTe:Ag films. The enhancement of thermoelectric power is thus attributed to the formation of Ag2−xTe alloy and the precipitation of Pb nanostructures on the surface. The origin of such enhancement is understood based on the phenomenon of energy dependent filtering of charge carriers.
Databáze: OpenAIRE