MECHANISM OF LUMINESCENCE OF CARBON MATERIALS

The article proposes a new mechanism for the occurrence of luminescence in graphite and graphene when excited by an electric field, laser, or external deformation. Most authors believe that there are two mechanisms in graphite that emit photons with a broadband spectrum. When graphite is excited by an electric current, radiation similar to thermal radiation occurs. When graphite is excited by a laser, anti-Stokes luminescence occurs. In a number of studies, photoluminescence of the forbidden band of carbon nanotubes was discovered. The observed luminescence of graphene is explained in terms of the mechanism of hot luminescence. A common characteristic of the radiation of carbon materials is broadband spectra, the causes of which are still not clear. A discrete system is responsible for the luminescence of graphite, which is in three electronic states - the ground, excited, and a state with separated charges. It is the processes of separation and recombination of charges that represent the luminescence process. The process of charge separation itself is inherent in the non-equilibrium of the nuclear subsystem, associated with the deformation of the crystal lattice due to the reconstruction of the graphite surface. This means that the glow of graphite, graphene and nanotubes, like hot luminescence, is carried out by converting the energy of surface deformation into the glow of a defect-free crystal.