Effects of gas pressure and plasma power on the growth of carbon nanostructures

Effects of gas pressure and plasma power on the growth of carbon-based nanostructures (CNSs) have been studied in detail. Multi-walled carbon nanotube (MWCNTs) and carbon nanowalls (CNWs) were synthesized on glass substrates via radio frequency plasma-enhanced chemical vapor deposition (RFPECVD) technique. Surface morphologies of the films have been studied by SEM and TEM. When the gas pressure increases from 120 to 300 Pa, the deposited carbon material changes from MWCNTs to carbon nanowalls (CNWs). Additionally, the density of carbon nanostructures increases with the gas pressure. The radio frequency (RF) plasma power ranging from 600 to 2400 W was applied during the activation and deposition process. The plasma enhances the decomposition of carbon atoms to deposit onto the surfaces of catalyst particles. Whereas an exorbitant RF plasma power can destroy the already deposited carbon nanostructures.