Thermal properties of X-ray study of Bi metal Nanopowders Prepared by Mechanical Milling

Bismuth metal nanopowders have been prepared by a Retsch Planetary PM 100-ball mill. The time of milling has been extended
up to 32 hours. After every spell of 4 hours of milling, XRD patterns have been recorded for Bi sample. The particle size has been
estimated using Hall-Williamson method. The Debye temperatures, Debye-waller factors and amplitudes of vibration of Bi metal
nanopowders have been obtained from integrated X-ray intensities. The intensities have been measured with an upgraded JEOL JDX
8P powder diffractometer fitted with a scintillation counter using filtered CuK radiation at room temperature and have been
corrected for TDS effect. The values of Debye temperature obtained for Bi metal nanoparticles have been compared with the values
obtained from other methods. The X-ray Debye temperatures obtained in the present work have been used to estimate the Ef values
for Bi metal nanoparticles. The Debye temperature of metal nanopowders of bismuth decreases from 122 K to 75 K with decreasing
particle size from 96 nm to 15 nm.