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Ab Initio Computational Study of Chromate Molecular Anion Adsorption on the Surfaces of Pristine and B- or N-Doped Carbon Nanotubes and Graphene

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 CrO(4) (2−) were performed within molecular cluster approach. Relaxed geometries, binding energies, charge differences...

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Detalles Bibliográficos
Autores principales: Hizhnyi, Yuriy, Nedilko, Sergii, Borysiuk, Viktor, Shyichuk, Andrii
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Springer US 2017
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5265242/
https://www.ncbi.nlm.nih.gov/pubmed/28120246
http://dx.doi.org/10.1186/s11671-017-1846-x
Descripción
Sumario: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 CrO(4) (2−) were performed within molecular cluster approach. Relaxed geometries, binding energies, charge differences of the adsorbed CrO(4) (2−) anions, and electronic wave function contour plots were calculated using B3LYP hybrid exchange-correlation functional. Oscillator strengths of electronic transitions of CrO(4) (2−) 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 CrO(4) (2−) anions, providing a ~2-eV increase in binding energies comparatively to adsorption of the anion on undoped adsorbents. Additional electronic transitions of CrO(4) (2−) 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).