Effect of the liquid environment on the formation of carbon nanotubes and graphene layers by arcing processes

The influence of the liquid environment on the formation of different carbon nanostructures by arcing processes, in particular liquid nitrogen (LN2) and de-ionised water (DI-H2O), has been investigated. Large structural differences between the nanomaterials produced in the two cases are shown: the use of DI-H2O induces a large number of pentagon–heptagon defects in the nanotubes, compared to the use of LN2. A large amount of graphene layers has been observed by scanning electron microscopy and transmission electron microscopy in the case of arc discharge in DI-H2O. Micro-Raman analysis confirms the electron microscopy results.