Borysiuk V. Influence of adsorbed atoms, molecules and their clusters on the electronic structure, conductivity and optical properties of carbon nanotubes.

The thesis deals with the study of the interaction of atoms, molecules and their clus-ters with the surface of carbon nanotubes with various defects: boron or nitrogen doping, or functionalization of the surface with oxygen- or ammonia-containing surface groups. The electronic structure of carbon nanotubes for adsorption hydrogen halide molecules HX (X = F, Cl, Br), molecular anions (MA) MVIO42- (MVI = Cr, Mo, W) and molecular complexes MI2CrO4 (MI = Li, Na, K) and MIICrO4 (MII = Ca, Zn, Cd, Hg, Pb) had been studied at the Density Functional Theory (DFT) level within molecular cluster approach using software package Gaussian 09. Calculations were performed for the cluster within B3LYP approximation for exchange-correlation functional. Calculated binding energies and values of electronic charges transferred to adsorbents were analysed, and the types of bonding between the investigated molecular compounds and the surface of carbon nano-tubes were identified. Adsorption characteristics dependence on the position of molecular anions CrO42- on the surface of carbon nanotubes was established. Effect of M+ (M+ =Li, Na, K) and M2+ (M2+ = Ca, Zn, Cd, Hg, Pb) cations on adsorption of molecular anions by the surface of carbon materials was studied. The influence of the most widely distributed atmospheric molecules (H2O, N2, O2) on CrO42- anions adsorption on the surface of carbon nanotubes was modelled in the calculations. It was found that simple organic functional groups increase the adsorption capacity of carbon nanotubes in an aqueous solution with respect to chromatic molecular anions. Experimental studies were carried out and analysis of the data those concern features of the Raman, absorption, diffuse reflection and lumi-nescent spectroscopy of the surfaces containing K2CrO4 molecular complexes adsorbed on the surface of carbon nanotubes was made.