Synthesis of Copper Nanoparticles on Graphite Using Transient Glow-to-Arc Discharge Plasma

Abstract

A transient glow-to-arc mode developed in a setup for ignition of the glow discharge plasma was employed to synthesize copper nanoparticles with 2 to 5 nm diameters on surfaces of complex 1D and 2D graphite nanostructures grown in craters formed during the arc generation. In the setup, a cathode and an anode were manufactured of graphite and copper, respectively. Graphite samples were arranged on the cathode. When igniting the plasma glow between the electrodes, the anode was considered as a source of a copper atomic flux, while the cathode served as a source of carbon atoms generated in abundant yield during the arc stage of the plasma discharge. Extreme conditions obtained on the surface of the samples subject to the arcing allowed the formation of complex carbon nanostructures densely covered by copper nanoparticles. TEM images obtained during a microscopic stage of the research revealed the sequential growth of the nanostructures, when 2D carbon nanostructures formed in the craters were covered by the copper nanoparticles that, in turn, served as the seeds for the formation of 1D carbon nanostructures on a body of the parent 2D carbon nanostructure. At that, the copper nanoparticles were covered by a few atomic layers of graphite during the growth of the complex carbon nanostructure.