Search

The change in the density of electronic states (DOS) near the Fermi level induced by doping, ionic and thermal treatments, is studied. The model of band structure of multi-walled carbon nanotubes (MWCNTs) containing various types of defects, is constructed using experimental data of the DOS near the Fermi level. In the framework of the temperature Green functions method the expression for DOS near the Fermi level is received for MWCNTs of large diameter with impurities and structural defects of short-range order type. The results of theoretical investigations are in a good agreement with the experimental data. The phenomenon of gap opening or closing in the DOS is explained. [ABSTRACT FROM AUTHOR]

One of the most rapidly developing areas of modern materials science is the study of graphene and materials on its basis. The experimental investigations have revealed different types of defects on the surface of graphene that form the ordered structures of atomic configurations. In the present work, the value of short-range order parameter for different configurations of foreign atoms in a graphene layer was calculated. The effect of various factors on the density of electronic states and electrical resistance in graphene was also investigated. The type of the ordering of foreign atoms in graphene rather than the concentration of impurities, was shown to be responsible for the change in the conductivity of graphene. [ABSTRACT FROM AUTHOR]