Experimental study of graphene synthesis by different gas-doped plasma

Plasma gas phase synthesis of graphene method is one-step synthesis, without catalyst, acid, solvent and substrate materials. In this paper, plasma pyrolysis of C2H4 for the preparation of graphene was carried out to investigate the effect of doping H2, CO2, and N2 on the morphology characteristics and chemical reaction properties of the synthesized products at different reaction temperatures ranging from 1500 to 4500 K. It was found that an increase in temperature leads to flatter morphology, less agglomeration, and a decrease in defect density and oxygen content in graphene. The addition of H2, CO2, and N2 gases affected the morphology and defect density of the products. In addition, the high temperature conditions increase the hydrogen atom concentration and etch the edges of graphene, while CO2 slows down the etching process and decreases the defect density. Doping with high enthalpy N2 favors the improvement of crystallinity and defect density at low temperatures, but increases the defect density at high temperatures. These findings contribute to further understanding of the application and optimization of the method of plasma gas phase synthesis of graphene.