Synthesis of graphene flakes using a non-thermal plasma based on magnetically stabilized gliding arc discharge

The use of non-thermal plasma at atmospheric pressure has emerged as a technique for the substrate-free, gas-phase synthesis of graphene nanoflakes (GNFs). In this paper, a non-thermal plasma based on magnetically stabilized gliding arc discharge (MSGAD) was employed to prepare GNFs. The effects of the carbon-containing precursor, plasma gas, and arc current on the GNFs synthesis were investigated. The technique produced GNFs with sizes of 50-200 nm and 1-20 layers, spherical carbon nanoparticles with 10-40 nm diameters, and graphitic particles. The results showed that the formation of GNFs depended on the selection of proper process parameters, such as precursors with a high H/C ratio, an Ar-N(2)plasma gas, a low arc current, a low precursor flow rate, and a suitable plasma gas flow rate. Correlations between the process parameters and the product morphology indicated that abundant H atoms and fewer polycyclic aromatic hydrocarbons were favorable for the formation of GNFs.