Preparation and oxidation resistance of single crystalline β-Zn4Sb3

This study prepared a Zn-rich single crystal beta-Zn4Sb3 using a Sn flux method based on the stoichiometric ratios of Zn4.4Sb3Sn3. The oxidation resistance of the sample was determined by exploring the effects of heat treatment in air on electrical transport properties and thermal stability, which is of practical importance in the application of the material at high temperatures. Results showed that the prepared sample possessed high electrical transport properties, with a high power factor of 1.67x10(-3) W m(-1) K-2 at 563 K. The heat treatment in air weakened the electrical conductivity of the single crystalline beta-Zn4Sb3, whereas the Seebeck coefficients were rarely independent of the annealing condition. Eventually, the power factor obtained after the first heating at 523 K for 4 h became comparable to that of the as-prepared sample, although it decreased after the second heating at 573 K for 5 h. Nevertheless, the single crystalline beta-Zn4Sb3 still possessed a good thermal stability after the heat treatment process. (C) 2016 Elsevier B.V. All rights reserved.