Influence of the pressure of a propane-butane mixture on the morphology of carbon nanomaterial formed in an arc discharge

The morphology of carbon material formed in an arc discharge in a mixture of i-butane, n-butane, and propane when spraying a graphite-nickel electrode was studied. The experiments were carried out with changing the gas medium pressure. Carbon globules, graphene structures, and carbon nanotubes have been discovered. It was found that at pressures of 75 and 400 torr, carbon globules predominate in the resulting materials. At gas pressures of 200 torr, the material collected from the cold screen surface contains both graphene-like structures and significant amounts of carbon nanotubes. The physical reasons influencing the observed phenomena are discussed.