title: Ab Initio Computational Study of Chromate Molecular Anion Adsorption on the Surfaces of Pristine and B- or N-Doped Carbon Nanotubes and Graphene.
abstract: Density functional theory (DFT) computations of the electronic structures of undoped, B- and N-doped CNT(3,3), CNT(5,5) carbon nanotubes, and graphene with adsorbed chromate anions CrO42-were performed within molecular cluster approach. Relaxed geometries, binding energies, charge differences of the adsorbed CrO42-anions, and electronic wave function contour plots were calculated using B3LYP hybrid exchange-correlation functional. Oscillator strengths of electronic transitions of CrO42-anions adsorbed on the surfaces of studied carbon nanostructures were calculated by the TD-DFT method. Calculations reveal covalent bonding between the anion and the adsorbents in all studied adsorption configurations. For all studied types of adsorbent structures, doping with N strengthens chemical bonding with CrO42-anions, providing a ~2-eV increase in binding energies comparatively to adsorption of the anion on undoped adsorbents. Additional electronic transitions of CrO42-anions appear in the orange-green spectral region when the anions are adsorbed on the N-doped low-diameter carbon nanotubes CNT(3,3) and CNT(5,5).
authors.affiliation: Faculty of Physics, Taras Shevchenko National University of Kyiv, 64/13 Volodymyrska St., 01601, Kyiv, Ukraine. hizhnyi@univ.kiev.ua.
authors.forename: Yuriy
authors.initials: Y
authors.lastname: Hizhnyi
authors.affiliation: Faculty of Physics, Taras Shevchenko National University of Kyiv, 64/13 Volodymyrska St., 01601, Kyiv, Ukraine.
authors.forename: Sergii
authors.initials: S
authors.lastname: Nedilko
authors.affiliation: Faculty of Physics, Taras Shevchenko National University of Kyiv, 64/13 Volodymyrska St., 01601, Kyiv, Ukraine.
authors.forename: Viktor
authors.initials: V
authors.lastname: Borysiuk
authors.affiliation: Department of Rare Earth, Faculty of Chemistry, Adam Mickiewicz University, Umultowska 89b, 61-614, Poznań, Poland.|Faculty of Chemistry, University of Wrocław, Joliot-Curie 14, 50-383, Wrocław, Poland.
authors.forename: Andrii
authors.initials: A
authors.lastname: Shyichuk
keywords: Adsorption; Binding energy; CNT; Chromate; Excited states; Graphene; TD-DFT