Encapsulation of Pollutant Gaseous Molecules by Adsorption on Boron Nitride Nanotubes: A Quantum Chemistry Study

Abstract

Based on density functional theory (DFT) and the semiempirical method PM7, we analyze the encapsulation process of polluting gases and/or their adsorption on different sites, viz., on the inner wall, the outer wall, and on the boron nitride (BN) nanotube ends, with chirality (7,7) armchair. DFT calculations are performed using the Perdew–Burke–Ernzerhof (PBE) functional and the M06-2X method through the 6-31G(d) divided valence orbitals as an atomic basis. Various geometrical configurations were optimized by minimizing the total energy for all analyzed systems, including the calculation of vibrational frequencies, which were assumed to be of a nonmagnetic nature, and where the total charge was kept neutral. Results are interpreted in terms of adsorption energy and electronic force, as well as on the analysis of quantum molecular descriptors for all systems considered. The study of six molecules, namely, CCl 4 , CS 2 , CO 2 , CH 4 , C 4 H 10 , and C 6 H 12 , in gas phase is addressed. Our results show that C 4 H 10 , C 6 H 12 , and CCl 4 are chemisorbed on the inner surfaces (encapsulation) and on the nanotube ends. In contrast, the other molecules CS 2 , CO 2 , and CH 4 show weak interaction with the nanotube surface, leading thereby to physisorption. Our findings thus suggest that this kind of polluting gases can be transported within nanotubes by encapsulation.

New Cap-Holed AlP, GaP, and InP Nanotubes

“…Table S1 shows the dipole moment, polarizability, and solvation energy of all investigated NTs. It is well-known that the open-end armchair NTs display null polarity as a consequence of the structural symmetry, regardless of the atomic species of which they are made. ,,,, The μ → values close to zero indicate that the curvature at the end of the new armchair cap-hole nanotubes induces only small distortions to the structure in such a way that they remain nonpolar systems. The polarizability (α) increases as one changes atoms from Al to In.…”

“…The global molecular descriptors are widely invoked to theoretically study the stability and reactivity of different molecular systems, among them are the III–V nanotubes. − …”

Structural Stability and Electronic Properties of Boron Phosphide Nanotubes: A Density Functional Theory Perspective

“…The reactivity chemical stability of the nanotubes was measured through global quantum molecular descriptors such as chemical potential (µ), global hardness (η) and electrophilicity index (ω), energy gap (E g ), ionization potential (I) and electronic affinity (A), as summarized in Tables 4 and 5. These parameters have been widely used for many years in computational chemistry studies [38][39][40][41] and, recently, to study the functionalization and stability of some III-V nanotubes [42][43][44][45][46]. The global hardness represents the system resistance to a charge transfer, that is, high values of η indicate greater electronic stability.…”

Insights on α‐Glucose Biosensors/Carriers Based on Boron‐Nitride Nanomaterials from an Atomistic and Electronic Point of View

“…PBE functional has a good performance for adsorption processes or sensing studies in BN nanomaterials and other low-dimensional systems. [31][32][33][34][35] The systems were considered with a neutral charge (Q = 0) and multiplicity 1 (M = 2S T + 1; S T = total spin). To ensure the stability of the systems, a vibrational frequency analysis was carried out for each.…”

“…Of the conformers analyzed with MOPAC, ∼20 structures were re‐optimized in the Kohn‐Sham scheme at the DFT framework applying the PBE functional [29] coupled to 6‐31G(d) basis set, [30] was done. PBE functional has a good performance for adsorption processes or sensing studies in BN nanomaterials and other low‐dimensional systems [31–35] . The systems were considered with a neutral charge (Q=0) and multiplicity 1 (M=2S T +1; S T =total spin).…”