Characterization of Ultra Fine Palladium Particles with the Mean Size of 20 A by X-Ray Diffraction

Abstract

Ultra fine palladium particles with the mean size of 20 A, prepared by VEROS (Vacuum Evaporation and Running Oil Substrate) method, were identified to be the same f.c.c. structure as the bulk specimen by X-ray diffraction method. The lattice parameter was found to be larger than the bulk value by an amount of 1.3%. From the profile analysis of the 220 Debye-Scherrer line the size distribution of the specimen was obtained, which is a very sharp distribution with a peak at 21±3 A. This result was confirmed by a direct measurement of electron micrograph.