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Simulating of Boron Atoms Interacting with a (10,0) Carbon Nano Tube: A DFT Study
Abstract
Using Density functional theory, I report the effects of adsorption and substitution of boron atoms on structural and electrical properties of a (10,0) carbon nanotubes (CNTs). By considering formation energy, I found that the substitution process is an exothermic process. On the opposite the adsorption process has positive formation energy. When CNT was contaminated by boron atoms, boron atoms behave as acceptors. Boron will turn the semiconducting (10,0) CNT into a metallic nanostructure. Boron induced high polarization on the tube. When boron atoms substitute with carbon atoms, the polarization is stronger in comparison when they adsorb with CNT.
... As the insertion energy increases, a majority of the B atoms tend to adsorb onto the inner wall of the DWNTs. This process involves either replacing carbon atoms in the first layer (i.e., doping), pulling carbon atoms out of the system, or breaking the first layer and adsorbing onto the second layer [51,52]. In our case, adsorbtion onto second wall of DWNT start at 6 eV energy of B atoms. ...
... The findings show that increasing the doping index of B atoms led to the corresponding result partial charge increase. This result is consistent with previous research findings [52]. B atoms are added (doped) to two DWNTs according to the maximum adsorption coverage (ρ%) and the partial charge (e) is compared. ...
Boron-adsorbing carbon nanotubes receive considerable attention in materials science due to their unique properties and potential applications. In particular, boron-adsorbing double-walled carbon nanotubes (DWNTs) exhibit a wide range of tunable electronic and optoelectronic properties. This study explores the influence of boron atoms on metallic (5,5@10,10) and semiconducting (8,0@17,0) DWNTs. We examine alterations in partial charge depending on the quantity of boron atoms adsorbed and affixed to the DWNT surface across temperatures from 300 K to 900 K. The results show that in both DWNTs, with the increase of energy corresponding to the temperature, the adsorption index of boron atoms (adsorbed to the first layer of DWNT) and the positive partial charge increase. Specifically, the maximum partial charge of DWNT(8,0)@(17,0) and DWNT(5,5)@(10,10) is 1.94 e and 1.30 e (at 300 K), 4.87 e and 3.66 e (at 600 K), 6.97 e and 6.16 e (at 900 K). Increasing boron concentration leads to heightened positive partial charge of DWNTs. This, in turn, affects the conductivity of the nanotube.
... The structural and physical properties of CNTs have been the subject of numerous studies during the last two decades, with the addition of dopants such as Li, B, N, Si, and Ge attracting attention from many researchers. DFT was applied to ascertain the electronic characteristics, geometric structures, and relative stabilities of endohedrally Lidoped zigzag and armchair SWCNTs [5], while Pyawarai (2020) [7] explained the influence of boron atom adsorption and substitution on the characteristics of (10, 0) CNTs. DFT calculations were also performed on (4, 0) SWCNTs doped with B, Ge, and Ga atoms by Gecim and Ozekmekci [6] to examine the molecular adsorption of hydrogen sulphide in SWCNTs, and Tavakol and Haghshenas [8] evaluated the interactions between pure and Al-, S-, P-, B-, N-, and Si-doped carbon nanotubes alongside three sulphur-containing compounds as a way to predict the resulting adsorption capacities and sensor capabilities. ...
... Finding a relation between bandgap ban effective mas that is one of important factor playing important role in transport, is also demanding. According to the band structure of a semiconductor, based on the relationship between energy and the k-wave vector, the effective mass can be expressed as [1][2][3][4][5][6][7][8]. ...
Dilute Nitride Semiconductor (low nitrogen-containing ternary and quaternary alloys) have recently attracted much attention due to their fundamental properties promising for device applications in optoelectronics and photonics such as highly efficient near infrared lasers, multi-junction solar cells, as well as heterojunction bipolar transistors (HBTs). The effect of N on the electronic band structure in dilute III-N-V nitrides has been explained in terms of a band anticrossing interaction between highly localized N states and the extended conduction band states of the semiconductor matrix. The interaction leads to a splitting of the conduction band into two non-parabolic subbands. The downward shift of the lower subband edge relative to the valence band is responsible for the reduction of the fundamental band gap. The profound effects on the optical and electrical properties of the dilute nitrides such as the significant increase in the electron effective mass can be quantitatively account for using this model.
... The chain modes have a more negative CE compared with random modes. Since more negative CE means a more stable structure [33,34], we expect the chain modes to be more stable than random modes. Figure 5 shows the density of states for pristine (a) and Au-doped BNNTs (b to i). ...
In this work, structural and electronic properties of zigzag single-walled boron nitride nanotube (BNNT) are considered through density functional theory. In order to reduce the large band gap of BNNT, the effects of 2-5 Au atoms are reported as impurities in two different patterns. We selected two dispersions for Au atoms: one for the random dispersion and the other for the chain dispersion. Our results show that the chain modes have lower formation energy and their band gap is smaller, as well. We could tune the large band gap of BNNT from 5.96 eV to 0.41 eV in chain mode. In the random mode, the band gap could reach a minimum level of 1.01 eV.
Carbon monoxide (CO) is known as a deathful gas produced by burning of hydrocarbons in a lack of enough oxygen, in which breathing CO leads to serious issues on human life health quality. Therefore, adsorption of CO gas is an essential task for diagnosis or removal of this dreadful gas in environment. To do this, a HEME-like model of iron-nitrogen-doped beryllium oxide (FeNBeO) monolayer was investigated for adsorbing CO gas by performing density functional theory (DFT) calculations. Two models were obtained for this process, in which relaxation of CO with C-head or O-head towards Fe region of monolayer. The results indicated that the formation of FeNBeO-CO model could be achieved more favorable than the formation of FeNBeO-OC model. The obtained optimized geometers and energies all approved this achievement for favorability of FeNBeO-CO model formation. Moreover, molecular orbital based electronic features indicated variations of such features for the models upon adsorption of CO substance, in which the models could be detectable in a sensor function for the existence of CO gas in the environment. As a consequence, the investigated FeNBeO monolayer could be proposed useful for adsorption of CO gas at least for the CO deathful gas diagnosis purposes.
The molecular adsorption of hydrogen sulfide has been investigated theoretically by using Density Functional Theory for gallium (Ga), germanium (Ge) and boron (B) doped (4,0) single-walled carbon nanotubes (SWCNTs). The method of B3LYP was utilized with basis sets of 6-31G(d,p) and LANL2DZ. Adsorption energy and adsorption enthalpy, HOMO and LUMO energy values, HOMO-LUMO energy gap, chemical hardness, chemical potential, electronegativity and Gibbs free energy values have been evaluated in this study. All doped SWCNT structures have negative Gibbs free energy and adsorption energy values which make these clusters promising for the removal of H2S by adsorption. However, Ge doped SWCNT cluster has the lowest HOMO-LUMO energy gap and chemical potential, highest electronegativity with minimum adsorption energy values when compared to other clusters. Furthermore, it is softer than other metal doped SWCNT clusters due to the lower chemical hardness value.
In this paper, structural and electronic properties and stability of (10, 0) born nitride nanotube (BNNT) are considered within density functional theory by doping group IV elements of the periodic table. The HOMO-LUMO gap has been strongly modified and treated a dual manner by choosing B or N sites for dopant atoms. Formation energy calculation shows that B site doping is more stable than N site doping. Results also show that all dopants turn the pristine BNNT into a p-type semiconductor except for carbon-doped BNNT at B site.
We use a simple picture based on theelectron approximation to study the bandgap variation of carbon nanotubes with uniaxial and torsional strain. We find (i) that the magnitude of slope of bandgap versus strain has an almost universal behaviour that depends on the chiral angle, (ii) that the sign of slope depends on the value of (n m) mod 3 and (iii) a novel change in sign of the slope of bandgap versus uniaxial strain arising from a change in the value of the quantum number corresponding to the minimum bandgap. Four orbital calculations are also presented to show that theorbital results are valid.
Substitutionally boron-doped multiwalled carbon nanotubes (B-CNTs) with lengths mainly less than 0.5μm and diameters 10–30 nm have been obtained by arc-discharge evaporation of the graphite anode containing boron material. The broad peak has been observed in the midinfrared conductivity spectra of the thin film comprising B-CNTs. The peak was suggested to be associated with a phenomenon known as localized plasmon resonance. Theoretical analysis has been done to confirm the possibility of this phenomenon to occur in the B-CNTs.
An atmospheric pressure, solution-assisted substitution process has been developed to produce boron-doped carbon nanotubes (BCNTs) with tunable boron dopant concentrations precisely from atomic percent of 0.4–3.9% by controlling the reaction conditions. The systematic material characterizations and detailed electrochemical sensor applications were studied. The electrochemical detection of dopamine (DA) can be improved by the enhanced electrocatalytic activity and reduced electron transfer resistance of BCNTs due to the boron doping. The effects of boron dopant concentrations on the electrocatalytic activity and electron transfer resistance of the BCNTs were investigated thoroughly in this study. It was found experimentally that the anodic peak current density (ipa) of DA is the highest (169.6 ± 8.9 μA cm⁻²) on the BCNTs (B 2.1 at.%) modified screen printed carbon electrode (SPCE). In this study, we have successfully developed a highly efficient and tunable synthesis of BCNTs in bulk quantities as the potential electrocatalysts for DA oxidation reaction. Also, it is noteworthy from a practical point of view that the developed atmospheric-pressure BCNTs synthesis method is amenable to industrial-scale production since it avoids the need for a vacuum system.
We report the fabrication of high-performance, self-standing composite sp2-carbon supercapacitor electrodes using single-walled carbon nanotubes as conductive binder. The 3-D mesoporous mesh architecture of CNT-based composite electrodes grants un-impaired ionic transport throughout relatively thick films and allows superior performance compared to graphene-based devices at a ac-line frequency of 120 Hz. Metrics of 601 µF/cm2 with a -81º phase angle and an RC time constant of 199 µs are obtained. The free-standing carbon films were obtained from a chlorosulfonic acid dispersion and interfaced to stainless steel current collectors with various surface treatments. CNT-electrodes were able to cycle at 200 V/s and beyond, still showing a characteristic parallelepipedic CV shape at 1 kV/s. Current densities are measured in excess of 6400 A/g and the electrodes retain more than 98% of capacity after one million cycles. These results are attributed to a reduction of series resistance in the film through the CNT conductive network and the surface treatment of the stainless steel current collector.
Density-functional theory methods are used to investigate the adsorption of nine prevalent gas molecules (H2, O2, CO, CO2, NO, NO2, H2O, CH3OH, and NH3) on a carbon nanotube-based support material. The support is a boron-doped, single-walled carbon nanotube, which has been sensitized by the adsorption of tungsten metal clusters. Our calculations demonstrate that this hybrid adsorbent material is able to adsorb the gas molecules with varied affinity, and these interactions are characterized by analyzing the features in the projected density-of-states for each system. These calculations represent a critical step in designing high-fidelity sensor materials, selective adsorbents, and more effective catalysts.
We have performed first-principles calculation to investigate the adsorption of a single palladium atom on the surface of the pristine and boron- or nitrogen-doped carbon nanotubes (CNTs). The results show that for the adsorption of a single palladium atom on the pristine CNT surface, the most stable site is Bridge1 site above the axial carbon–carbon bond. Either boron- or nitrogen-doped CNTs can assist palladium surface adsorption, but the detailed mechanisms are different. The enhanced palladium adsorption on boron-doped CNT is attributed to the palladium d orbital strongly hybridized with both boron p orbital and carbon p orbital. The enhancement in palladium adsorption on nitrogen-doped CNT results from activating the nitrogen-neighboring carbon atoms due to the large electron affinity of nitrogen. Furthermore, the axial bond is preferred over the zigzag bond for a palladium atom adsorbed on the surface of all three types of CNTs. The most energetically favorable site for a palladium atom adsorbed on three types of CNTs is above the axial boron–carbon bond in boron-doped CNT. The enhancement in palladium adsorption is more significant for the boron-doped CNT than it is for nitrogen-doped CNT with a similar configuration. So we conclude that accordingly, the preferred adsorption site is determined by the competition between the electron affinity of doped and adsorbed atoms and preferred degree of the axial bond over the zigzag bond.
We present a systematic study for numerical atomic basis orbitals ranging from H to Kr, which could be used in large scale O(N) electronic structure calculations based on density-functional theories (DFT). The comprehensive investigation of convergence properties with respect to our primitive basis orbitals provides a practical guideline in an optimum choice of basis sets for each element, which well balances the computational efficiency and accuracy. Moreover, starting from the primitive basis orbitals, a simple and practical method for variationally optimizing basis orbitals is presented based on the force theorem, which enables us to maximize both the computational efficiency and accuracy. The optimized orbitals well reproduce convergent results calculated by a larger number of primitive orbitals. As illustrations of the orbital optimization, we demonstrate two examples: the geometry optimization coupled with the orbital optimization of a C60 molecule and the preorbital optimization for a specific group such as proteins. They clearly show that the optimized orbitals significantly reduce the computational efforts, while keeping a high degree of accuracy, thus indicating that the optimized orbitals are quite suitable for large scale DFT calculations.
A simple and practical method for variationally optimizing numerical atomic orbitals used in density functional calculations is presented based on the force theorem. The derived equation provides the same procedure for the optimization of atomic orbitals as that for the geometry optimization. The optimized orbitals well reproduce convergent results calculated by a larger number of unoptimized orbitals. In addition, we demonstrate that the optimized orbitals significantly reduce the computational effort in the geometry optimization, while keeping a high degree of accuracy.
We have performed first-principles calculations to investigate the origin of adsorption of platinum on nitrogen- and boron-doped carbon nanotubes (CNTs). Our calculation results reveal that both nitrogen- and boron-doped CNTs can assist the reactivity of platinum adsorption on the CNT surface, although the detailed mechanisms are very different. For nitrogen-doped CNTs, the enhanced adsorption results from activation of the nitrogen-neighboring carbon atoms due to the large electron affinity of nitrogen. In this case, the nitrogen atoms mediate the platinum adsorption enhancement on the CNT surface. In contrast, the enhanced platinum adsorption in boron-doped CNTs can be attributed to the strong hybridization between the platinum d orbital and boron p orbital. Our results explain the experimentally observed enhanced adsorption of platinum on nitrogen-doped CNTs and also suggest that boron-doped CNTs may be a better candidate for fuel cell applications.
A systematic study was carried out to dope single-walled carbon nanotube (SWNT) bundles with varying amounts of boron using the pulsed laser vaporization technique. Targets containing boron concentrations ranging from 0.5 to 10 at.% boron were prepared by mixing elemental boron with carbon paste and the Co/Ni catalysts. The laser-generated products that were obtained from these targets were characterized by high resolution transmission electron microscopy, electron energy loss spectroscopy (EELS), thermoelectric power (TEP) measurements, and Raman scattering experiments. Electron microscopy and Raman studies revealed that the presence of various levels of boron concentration in the target strongly affected the products that were prepared. SWNTs were found in the products prepared from targets containing up through 3 at.% boron, and high resolution EELS estimated that less than 0.05–0.1 at.% boron is present in the SWNT lattice. The absence of SWNT bundles in the products derived from targets containing more than 3 at.% boron implies that the presence of excess boron in the carbon plume severely inhibits the carbon nanotube growth. The overall effect of the boron incorporation primarily leads to: (i) a systematic increase in intensity of the disorder-induced band (D-band) upon boron doping, with increasing D-band intensity observed for higher doping levels, (ii) a systematic downshift in the G′-band frequency due the relatively weaker C–B bond, and (iii) a non-linear variation in the RBM and G′-band intensities which is attributed to shifts in resonance conditions in the doped tubes. Resonant Raman spectroscopy thus provides large changes in the intensity of prominent features even when the dopant concentration is below the detectable limit of EELS (0.05–0.1 at.%). Thermoelectric power data also provide complementary evidence for the presence of a small boron concentration in the SWNT lattice which transforms the SWNTs into a permanently p-type material.
Carbon materials should have specific centers for hydrogen adsorption/absorption. The Universal Force Field and Density Functional Theory have been used to find the role of heteroatom substitution in carbon nanotubes as an activator. The effect of various heteroatoms like nitrogen, phosphorus, sulphur and boron for hydrogen activation and their geometrical positions has been identified for easy hydrogenation. This will be one of the possible centers where hydrogen adsorption/absorption is initiated.
A metal-free electrocatalyst has been developed by doping carbon nanotubes with electron-deficient boron. The good performance in the oxygen reduction reaction originates from the enhanced O2 chemisorption and effective utilization of π electrons in the conjugated carbon from the boron doping, as revealed by DFT calculations.
The stability and electronic structure of single-walled carbon nanotubes with B/N co-doping are investigated in detail by using the first-principles theory. From eight possible B/N co-doping configurations, it is found that the one with substitutional B and N atoms located at neighboring sites has a smaller formation energy than that with separate B/N atoms. The electronic structure of armchair carbon nanotubes evolves from metallic to semiconducting as a result of B/N co-doping, whereas the energy gaps of the intrinsically semiconducting nanotubes are reduced significantly. In contrast, the small zigzag nanotubes always remain metallic properties due to their large curvature effects except (5, 0) after B/N co-doping. As the atomic concentration of B/N co-doping is increased, the energy gaps of carbon nanotubes oscillate around a constant level, which is much lower than the energy gap of BC(2)N nanotubes. Moreover, the B/N co-doped carbon nanotubes with B- or N-rich impurities exhibit the characteristics of an acceptor or donor, respectively, since their electronic structures are significantly influenced by the occupied states in the valence and conduction bands due to the shifting of the Fermi level.
Generalized gradient approximations (GGA{close_quote}s) for the exchange-correlation energy improve upon the local spin density (LSD) description of atoms, molecules, and solids. We present a simple derivation of a simple GGA, in which all parameters (other than those in LSD) are fundamental constants. Only general features of the detailed construction underlying the Perdew-Wang 1991 (PW91) GGA are invoked. Improvements over PW91 include an accurate description of the linear response of the uniform electron gas, correct behavior under uniform scaling, and a smoother potential. {copyright} {ital 1996 The American Physical Society.}
First principles study of a heavily nitrogen-doped (10, 0) carbon nanotube, Physica E: Low-dimensional Systems and Nanostructures
- M Jamshidi
- M Razmara
- B Nikfar
- M Amiri
M. Jamshidi, M. Razmara, B. Nikfar, M. Amiri, First principles
study of a heavily nitrogen-doped (10, 0) carbon nanotube,
Physica E: Low-dimensional Systems and Nanostructures, (2018).