Abstract

Multi shell graphite coated Ag nano particles with core/shell structure were successfully synthesized by pulsed wire evaporation (PWE) method. Ar and CH_4 (10 vol.%) gases were mixed in chamber, which played a role of carrier gas and reaction gas, respectively. Graphite layers on the surface of silver nano particles were coated indiscretely. However, the graphite layers are detached, when the particles are heated up to 250°C in the air atmosphere. In contrast, the graphite coated layer was stable under Ar and N_2 atmosphere, though the core/shell structured particles were heated up to 800°C. The presence of graphite coated layer prevent agglomeration of nanoparticles during heat treatment. The dispersion stability of the carbon coated Ag nanoparticles was higher than those of pure Ag nanoparticles.

• Keywords: Core/shell structure;Carbon coated Ag;Nano particles;