Phase-Transition-Dependent Conductivity and Thermoelectric Property of Silver Telluride Nanowires

Abstract

Silver telluride nanowires have been synthesized by the composite-hydroxide-mediated (CHM) method at temperatures of 180−225 °C. The products were single-crystalline nanowires and monoclinic phase Ag2Te with a high purity. The reversible structural phase transition from monoclinic structure (β-Ag2Te) to face-centered cubic structure (α-Ag2Te) around 148/133 °C was observed during the heating/cooling process. The latent heat of the phase transition was calculated. The electrical resistance and thermal emf versus temperature were for the first time investigated on the Ag2Te nanowires. Abrupt changes of conductivity and Seebeck coefficient around the phase transition temperature were observed. The maximum Seebeck coefficient is ∼170 and ∼160 μV K−1 during the heating and cooling process, respectively, indicating a promising one-dimensional thermoelectric material as a building block to construct nanodevices.