New technique of amorphous metal nanoparticles production by liquid drop breakup in an electron beam

Abstract

Phone: þ7 (812) 292 73 92, Fax: þ7 (812) 297 10 17 We report a new technique of amorphous metal nanoparticles fabrication based on generation of liquid metal microdrops, their charging in electron flux with subsequent drops fission. Fission of charged metal drop occurs when its charge exceeds a critical value given by Rayleigh instability condition. Nanosize droplets, resulted from fission, cool down at extremely high rate to produce amorphous metal nanoparticles. Initial metal microdrops are generated at the end of an anode tip exposed to strong electric field and electron flux focused to the tip. The emitted drops then enter an electron beam where they are charged up to instability and are involved in fission process. To eliminate secondary electron emission (SEE) which can prevent drop charging we used electron beams of low energy. With beam energy properly chosen, SEE coefficient is less then unity for all drop sizes and drop charging up to unstable state is ensured. Granular films consisting of amorphous copper particles 2 nm in size are fabricated by the described technique. The results of atomic force microscopy (AFM) and transmission electron microscopy (TEM) studies of the fabricated films are presented. Possible applications of the fabricated structures related to their unusual properties are considered.

Fabrication of Amorphous Silver Nanowires by Helium Ion Beam Irradiation

“…Several methods including liquid metal micro drops, [6] pulse sonoelectrochemical technique and ion irradiation have been used to synthesize amorphous metals. [7−9] Li et al have synthesized the amorphous CoPt nanowires through direct current electrodeposition.…”