investigation of adsorption of aromatic dyes by carbon nanotubes: a dft study of nmr parameters

in this study, the adsorption of aromatic dyes on the surface of carbon nanotubes was investigated by quantum mechanical calculations. exploring a novel sensor for detection of toxic aromatic compounds, interaction of pristine single-walled carbon nanotubes (5, 0) zigzag cnt (swcnt) was investigated using the density functional theory (dft) within the local density approximation. it was found that the pristine cnt can effectively interact with aromatic dyes. so that their electronic and structural properties are changed upon exposure to aromatic compounds. in the most stable configuration, the binding energy is negative (e_ad= -3.922 kcal/mol) and suggesting that the absorption reaction is possible. the impacts of the estereoelectronic effect associated with donor-acceptor electron delocalizations on the structural and electronic properties and reactivity of zigzag open-end single wall carbon nanotubes (swcnts) as nano adsorbents in interaction with aromatic dyes was studied based on the dft calculations. the total electronic energy, orbital energies, density of state (dos), lumo-homo energy bond gaps, adsorption energies (ead) were calculated. moreover, nuclear magnetic resonance (nmr) shielding tensors were calculated by using the gauge independent atomic orbital (giao) method in order to determination of intramolecular interactions and chemical properties of molecules.