Nanocrystals synthesized by electron-beam induced fragmentation of vacancy-containing metals microspheres

Abstract

Dynamic behavior of gold spheres ranging from 5 to 50 μm in diameter under pulsed electron beam irradiation was observed in situ by a scanning and transmission electron microscope. Unusually large amounts of dropletlike fragments were found to be ejected out from spheres containing vacancies such as voids or holes. Crystals ranging from 1 nm to 1 μm in size were formed on a carbon substrate from the fragments. The ejection phenomenon may offer an alternative to laser ablation as a means of forming small particles.