Structural phase transformation of FePt nanoparticles by ion irradiation

Abstract

In the present study, post-deposition 5 keV He irradiation has been performed on such gas phase prepared FePt nanoparticles. Structural characterization of the samples is carried out by means of high resolution transmission electron microscopy (HRTEM). The power spectra obtained by Fourier transform of the original images clearly show that the particles are multiply twinned and of icosahedral structure but after irradiation, the particles are now of single crystal fcc structure and their mean diameter is reduced. This size reduction is ascribed to irradiation induced sputtering of the particles.