▎ 摘　　要

A multiscale theoretical model to study the effect of different gas mixtures on the nucleation and growth kinetics of a graphene nanosheet in the reactive low-temperature plasma environment has been developed. The model includes the plasma sheath formalization, kinetics of all the plasma species, charging of the graphene sheet, plasma-surface interaction, clusters and graphene islands nucleation, and vertical growth of a graphene nanosheet. The three different gas mixtures, i.e., C2H2, CH4, and CF4 with hydrogen and argon, are considered in the present investigation to examine the variations in the number densities of carbon and hydrogen species generated on the catalyst surface and their consecutive effects on the dimensions ( i.e., height and thickness) and number density profiles of the graphene nanosheet. It is found that the thickness and height of the graphene sheet are maximum for C2H2 gas mixtures and least for CH4 and CF4, respectively. On the basis of the results obtained, the field emission characteristics of the graphene sheet have been analyzed, and it is estimated that C2H2 contained gas mixture enhances the field emission characteristics of the graphene sheet followed by CH4 and CF4. The presented results are in good agreement with the existing experimental observations. Published by AIP Publishing.