Manufacturing and characterization of nano-sized PbTe powders

Nano-sized PbTe powders were manufactured by the high energy ball milling of a PbTe bulk, obtained by the water quenching of a melt. The wet milling using an ethanol were applied during the ball milling. The prepared powders were characterized by the X-ray powder diffraction pattern analysis to obtain crystallographic parameters such as the crystallite size and the misfit strain. A pseudo-Voigt function was used for the determination of the integral breadth and the full width at half maximum (FWHM) of peaks broadened by the effect of crystallite size and misfit strain. The Scherrer method, the Williamson-Hall plot and the single peak analysis were employed to calculate the size of crystallite and misfit strain with the consideration of instrumental broadening using standard sample. As results, we can observe the tendency that the crystallite size decreases and the misfit strain increases with increasing milling time. The crystallite size of powders was determined at the range of 15∼100 nm in 50∼150 hours milling time. The crystallite size and the misfit strain were different from crystallographic directions in this material, according to the Williamson-Hall plot and the single peak analysis.