Positron Annihilation Spectroscopic Studies of Cu₂Te Thermoelectric Material

Abstract:

Positron annihilation lifetime spectroscopy (PALS) and coincident Doppler-broadening spectroscopy (CDBS) have been used for investigating the evolution of vacancy-type defects in the thermoelectric material Cu₂Te which annealed at different temperatures. The results of PALS show that a fraction of positrons has got annihilated at the surfaces and the sample which annealed at 450 °C has the highest concentration of surface defects. The average positron lifetime and the S parameter have the same trends which gradually increase with the increase of the annealing temperature. This change implies that the total concentration of the defects has been changed with the change of the annealed temperatures. The results of the CDBS ratio spectrum and S-W plot indicate that the defect species have no change after annealing at different temperatures.

• Periodical: Defect and Diffusion Forum (Volume 373)
• Pages: 231-236
• DOI: https://doi.org/10.4028/www.scientific.net/DDF.373.231
• Online since: March 2017
• Authors: Wen Na Ge, Ju Ping Xu, Run Ye, Jian Dang Liu, Bang Jiao Ye*
• Keywords: Defect, Positron, Thermoelectric

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