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Title: First-principles calculations of the indigo encapsulation and adsorption by MgO nanotubes

Abstract

We have performed ab-initio calculations to investigate the structural and electronic properties of (m,m) chiral magnesium oxide nanotubes, (m,m)MgONTs, to explore the encapsulation, inclusion, and adsorption of dyes (organic molecules) such as Indigo (IND). Studies start by determining the structural parameters of the MgO nanotubes with different diameters and the IND. The indigo encapsulation into the MgONT is studied considering four (m,m) chiralities which yield 4 different NT diameters. In the endohedral functionalization, the indigo is within the NT at a tilt angle as in previous theoretical studies of organic molecules inside carbon and boron-nitride nanotubes. Results show that the encapsulation is a strong exothermic process with the m = 6 case exhibiting the largest encapsulation energy. It is also explored the indigo adsorption on the NT surface in the parallel and perpendicular configurations. The perpendicular configuration of the IND adsorption on the (8,8)MgONT exhibits the largest energy. The indigo inclusion within the NTs meets a potential barrier when m < 6, however this barrier diminishes as the index increases. Additionally, we have determined the total density of states (DOS), partial DOS, electron charge redistributions, and the highest occupied molecular orbital–lowest unoccupied molecular orbital levels for the NTs with m = 6. Very strong binding energiesmore » and electron charge transfer from the IND to NTs is present in the atomic structures.« less

Authors:
;  [1];  [2];  [3]
  1. Instituto de Física “Ing. Luis Rivera Terrazas,” Benemérita Universidad Autónoma de Puebla, Av. San Claudio y Blvd. 18 Sur, Col. San Manuel, C.P. 72570 Puebla, Pue (Mexico)
  2. Departamento de Materiales y Corrosión, Centro de Investigación en Corrosión, Universidad Autónoma de Campeche, Col. Buenavista, C.P. 24039 San Francisco de Campeche, Campeche (Mexico)
  3. Centro de Nanociencias y Nanotecnología, Universidad Nacional Autónoma de México, Km 107 Carretera Tijuana-Ensenada, CP. 22800 Ensenada, B.C (Mexico)
Publication Date:
OSTI Identifier:
22304249
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 115; Journal Issue: 21; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
77 NANOSCIENCE AND NANOTECHNOLOGY; ADSORPTION; BINDING ENERGY; BORON NITRIDES; CARBON; CHIRALITY; CONFIGURATION; DENSITY; DIFFUSION BARRIERS; ENCAPSULATION; INDIGO; MAGNESIUM OXIDES; MOLECULAR ORBITAL METHOD; MOLECULES; NANOTUBES; SURFACES

Citation Formats

Sánchez-Ochoa, F., E-mail: fsanchez@ifuap.buap.mx, Cocoletzi, Gregorio H., Canto, Gabriel I., and Takeuchi, Noboru. First-principles calculations of the indigo encapsulation and adsorption by MgO nanotubes. United States: N. p., 2014. Web. doi:10.1063/1.4881455.
Sánchez-Ochoa, F., E-mail: fsanchez@ifuap.buap.mx, Cocoletzi, Gregorio H., Canto, Gabriel I., & Takeuchi, Noboru. First-principles calculations of the indigo encapsulation and adsorption by MgO nanotubes. United States. doi:10.1063/1.4881455.
Sánchez-Ochoa, F., E-mail: fsanchez@ifuap.buap.mx, Cocoletzi, Gregorio H., Canto, Gabriel I., and Takeuchi, Noboru. Sat . "First-principles calculations of the indigo encapsulation and adsorption by MgO nanotubes". United States. doi:10.1063/1.4881455.
@article{osti_22304249,
title = {First-principles calculations of the indigo encapsulation and adsorption by MgO nanotubes},
author = {Sánchez-Ochoa, F., E-mail: fsanchez@ifuap.buap.mx and Cocoletzi, Gregorio H. and Canto, Gabriel I. and Takeuchi, Noboru},
abstractNote = {We have performed ab-initio calculations to investigate the structural and electronic properties of (m,m) chiral magnesium oxide nanotubes, (m,m)MgONTs, to explore the encapsulation, inclusion, and adsorption of dyes (organic molecules) such as Indigo (IND). Studies start by determining the structural parameters of the MgO nanotubes with different diameters and the IND. The indigo encapsulation into the MgONT is studied considering four (m,m) chiralities which yield 4 different NT diameters. In the endohedral functionalization, the indigo is within the NT at a tilt angle as in previous theoretical studies of organic molecules inside carbon and boron-nitride nanotubes. Results show that the encapsulation is a strong exothermic process with the m = 6 case exhibiting the largest encapsulation energy. It is also explored the indigo adsorption on the NT surface in the parallel and perpendicular configurations. The perpendicular configuration of the IND adsorption on the (8,8)MgONT exhibits the largest energy. The indigo inclusion within the NTs meets a potential barrier when m < 6, however this barrier diminishes as the index increases. Additionally, we have determined the total density of states (DOS), partial DOS, electron charge redistributions, and the highest occupied molecular orbital–lowest unoccupied molecular orbital levels for the NTs with m = 6. Very strong binding energies and electron charge transfer from the IND to NTs is present in the atomic structures.},
doi = {10.1063/1.4881455},
journal = {Journal of Applied Physics},
number = 21,
volume = 115,
place = {United States},
year = {Sat Jun 07 00:00:00 EDT 2014},
month = {Sat Jun 07 00:00:00 EDT 2014}
}
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