scholarly journals Integrating single-cobalt-site and electric field of boron nitride in dechlorination electrocatalysts by bioinspired design

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Yuan Min ◽  
Xiao Zhou ◽  
Jie-Jie Chen ◽  
Wenxing Chen ◽  
Fangyao Zhou ◽  
...  
Keyword(s):  
Boron Nitride ◽  
Electric Field ◽  
Active Sites ◽  
Density Functional ◽  
Electric Field Effect ◽  
Theory Analysis ◽  
Functional Theory ◽  
Co Catalyst ◽  
Carbon Doped ◽  
Organic Chloride

AbstractThe construction of enzyme-inspired artificial catalysts with enzyme-like active sites and microenvironment remains a great challenge. Herein, we report a single-atomic-site Co catalyst supported by carbon doped boron nitride (BCN) with locally polarized B–N bonds (Co SAs/BCN) to simulate the reductive dehalogenases. Density functional theory analysis suggests that the BCN supports, featured with ionic characteristics, provide additional electric field effect compared with graphitic carbon or N-doped carbon (CN), which could facilitate the adsorption of polarized organochlorides. Consistent with the theoretical results, the Co SAs/BCN catalyst delivers a high activity with nearly complete dechlorination (~98%) at a potential of −0.9 V versus Ag/AgCl for chloramphenicol (CAP), showing that the rate constant (k) contributed by unit mass of metal (k/ratio) is 4 and 19 times more active than those of the Co SAs/CN and state-of-the-art Pd/C catalyst, respectively. We show that Co single atoms coupled with BCN host exhibit high stability and selectivity in CAP dechlorination and suppress the competing hydrogen evolution reaction, endowing the Co SAs/BCN as a candidate for sustainable conversion of organic chloride.

Density Functional Theory Study of Antioxidant Adsorption onto Single- Wall Boron Nitride Nanotubes: Design of New Antioxidant Delivery Systems

2019 ◽  
Vol 22 (7) ◽  
pp. 470-482
Author(s):  
Samereh Ghazanfary ◽  
Fatemeh Oroojalian ◽  
Rezvan Yazdian-Robati ◽  
Mehdi Dadmehr ◽  
Amirhossein Sahebkar
Keyword(s):  
Density Functional Theory ◽  
Boron Nitride ◽  
Vitamin C ◽  
Electric Field ◽  
External Electric Field ◽  
Lipoic Acid ◽  
Density Functional ◽  
Cell Interaction ◽  
Boron Nitride Nanotubes ◽  
Functional Theory

Background: Boron Nitride Nanotubes (BNNTs) have recently emerged as an interesting field of study, because they could be used for the realization of developed, integrated and compact nanostructures to be formulated. BNNTs with similar surface morphology, alternating B and N atoms completely substitute for C atoms in a graphitic-like sheet with nearly no alterations in atomic spacing, with uniformity in dispersion in the solution, and readily applicable in biomedical applications with no obvious toxicity. Also demonstrating a good cell interaction and cell targeting. Aim and Objective: With a purpose of increasing the field of BNNT for drug delivery, a theoretical investigation of the interaction of Melatonin, Vitamin C, Glutathione and lipoic acid antioxidants using (9, 0) zigzag BNNTs is shown using density functional theory. Methods: The geometries corresponding to Melatonin, Vitamin C, Glutathione and lipoic acid and BNNT with different lengths were individually optimized with the DMOL3 program at the LDA/ DNP (fine) level of theory. Results: In the presence of external electric field Melatonin, Vitamin C, Glutathione and lipoic acid could be absorbed considerably on BNNT with lengths 22 and 29 Å, as the adsorption energy values in the presence of external electric field are considerably increased. Conclusion: The external electric field is an appropriate technique for adsorbing and storing antioxidants on BNNTs. Moreover, it is believed that applying the external electric field may be a proper method for controlling release rate of drugs.

scholarly journals Tuning Electronic Structures of BN and C Double-Wall Hetero-Nanotubes

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Xueran Liu ◽  
Meijun Han ◽  
Xinjiang Zhang ◽  
Haijun Hou ◽  
Shaoping Pang ◽  
...  
Keyword(s):  
Boron Nitride ◽  
Electric Field ◽  
Electronic Structures ◽  
Density Functional ◽  
Transverse Electric ◽  
First Principle ◽  
Generalized Gradient ◽  
Functional Theory ◽  
Generalized Gradient Approximation ◽  
Double Wall

First principle calculations based on density functional theory with the generalized gradient approximation were carried out to investigate the energetic and electronic properties of carbon and boron nitride double-wall hetero-nanotubes (C/BN-DWHNTs) with different chirality and size, including an armchair (n,n) carbon nanotube (CNT) enclosed in (m,m) boron nitride nanotube (BNNT) and a zigzag (n, 0) CNT enclosed in (m, 0) BNNT. The electronic structure of these DWHNTs under a transverse electric field was also investigated. The ability to tune the band gap with changing the intertube distance (di) and imposing an external electric field (F) of zigzag DWHNTs provides the possibility for future electronic and electrooptic nanodevice applications.

Selective heterogeneous hydrodeoxygenation of acetophenone over monometallic and bimetallic Pt–Co catalyst

2021 ◽  
Vol 379 (2209) ◽  
pp. 20200346
Author(s):  
Natalia Pino ◽  
Jennifer Quinchia ◽  
Santiago Gómez ◽  
Juan F. Espinal ◽  
Alejandro Montoya ◽  
...  
Keyword(s):  
Gas Phase ◽  
Density Functional ◽  
Bimetallic Catalyst ◽  
Advanced Materials ◽  
Theory Analysis ◽  
Theme Issue ◽  
Functional Theory ◽  
Co Catalyst ◽  
Bimetallic Systems ◽  
Products Of Reaction

The hydrodeoxygenation (HDO) of acetophenone was evaluated in liquid phase and gas phase over monometallic Pt/SiO 2 , Co/SiO 2 and bimetallic Pt–Co/SiO 2 catalysts. The influence of reaction time and loading of the catalyst were analysed by following the conversion and products selectivity. Phenylethanol, cyclohexylethanone and cyclohexylethanol are the main products of reaction using the Pt/SiO 2 catalyst. By contrast, ethylbenzene and phenylethanol are the only products formed on the Co/SiO 2 and Pt–Co/SiO 2 catalysts. The bimetallic catalyst is more stable as a function of time and more active towards the HDO process than the monometallic systems. The presence of an organic solvent showed only minor changes in product yields with no effect on the product speciation. Periodic density functional theory analysis indicates a stronger interaction between the carbonyl group of acetophenone with Co than with Pt sites of the mono and bimetallic systems, indicating a key activity of oxophilic sites towards improved selectivity to deoxygenated products. This article is part of the theme issue ‘Bio-derived and bioinspired sustainable advanced materials for emerging technologies (part 2)’.

Influence of Electric Field on the Mechanical Properties of Hexagonal Boron-Nitride Sheets Using ab-initio Calculations

NANO ◽  
2015 ◽  
Vol 10 (03) ◽  
pp. 1550047 ◽  
Author(s):  
R. Ansari ◽  
S. Malakpour ◽  
M. Faghihnasiri ◽  
S. Ajori
Keyword(s):  
Mechanical Properties ◽  
Boron Nitride ◽  
Electric Field ◽  
Density Functional ◽  
Hexagonal Boron Nitride ◽  
High Sensitivity ◽  
Functional Theory ◽  
Zigzag Direction ◽  
Electric Filed ◽  
Armchair Direction

In some cases such as assembling nanodevices and nanobiosensing, the effect of electric filed on the mechanical properties of nanomaterials is important and should be taken into account. The aim of this work is to investigate the effect of electric field on the mechanical properties of hexagonal boron-nitride (h-BN) using density functional theory (DFT) calculations. The results show the high sensitivity of mechanical properties to the magnitude and direction of electric field. It is observed that imposing the electric field on the armchair direction, unlike the zigzag direction, increases the magnitude of elastic properties of h-BN especially in the case of Poisson's ratio. It is further observed that the electric field perpendicular to h-BN has a negligible effect on its mechanical properties.

scholarly journals Reactivity of Atomically Functionalized C-Doped Boron Nitride Nanoribbons and Their Interaction with Organosulfur Compounds

Nanomaterials ◽  
2019 ◽  
Vol 9 (3) ◽  
pp. 452
Author(s):  
Francisco Villanueva-Mejia ◽  
Pedro Navarro-Santos ◽  
Peter Rodríguez-Kessler ◽  
Rafael Herrera-Bucio ◽  
José Rivera
Keyword(s):  
Boron Nitride ◽  
Density Functional ◽  
Stable Solution ◽  
Electronic States ◽  
Organosulfur Compounds ◽  
Generalized Gradient ◽  
Functional Theory ◽  
Carbon Doped ◽  
The Density Functional Theory ◽  
Boron Nitride Nanoribbons

The electronic and reactivity properties of carbon doped (C-doped) boron nitride nanoribbons (BNNRs) as a function of the carbon concentration were investigated in the framework of the density functional theory within the generalized gradient approximation. We found that the main routes to stabilize energetically the C-doped BNNRs involve substituting boron atoms near the edges. However, the effect of doping on the electronic properties depends of the sublattice where the C atoms are located; for instance, negative doping (partial occupations of electronic states) is found replacing B atoms, whereas positive doping (partial inoccupation of electronic states) is found when replacing N atoms with respect to the pristine BNNRs. Independently of the even or odd number of dopants of the C-doped BNNRs studied in this work, the solutions of the Kohn Sham equations suggest that the most stable solution is the magnetic one. The reactivity of the C-doped BNNRs is inferred from results of the dual descriptor, and it turns out that the main electrophilic sites are located near the dopants along the C-doped BNNRs. The reactivity of these nanostructures is tested by calculating the interaction energy between undesirable organosulfur compounds present in oil fuels on the C-doped BNNRs, finding that organosulfur compounds prefer to interact over nanosurfaces with dopants substituted on the B sublattice of the C-doped BNNRs. Most importantly, the selective C doping on the BNNRs offers the opportunity to tune the properties of the BNNRs to fit novel technological applications.

A density functional theory analysis for the adsorption of the amine group on graphene and boron nitride nanosheets

2012 ◽  
Vol 19 (1) ◽  
pp. 321-328 ◽  
Author(s):  
Ernesto Chigo Anota ◽  
Alejandro Rodríguez Juárez ◽  
Miguel Castro ◽  
Heriberto Hernández Cocoletzi
Keyword(s):  
Density Functional Theory ◽  
Boron Nitride ◽  
Density Functional ◽  
Amine Group ◽  
Theory Analysis ◽  
Functional Theory ◽  
Boron Nitride Nanosheets

CARBON-SUBSTITUTING IN (4,4) BORON NITRIDE NANOTUBE: DENSITY FUNCTIONAL STUDY OF BORON-11 AND NITROGEN-14 ELECTRIC FIELD GRADIENT TENSORS

2008 ◽  
Vol 07 (03) ◽  
pp. 447-455 ◽  
Author(s):  
AHMAD SEIF ◽  
ASADOLLAH BOSHRA ◽  
MAHMOUD MIRZAEI ◽  
MEHRAN AGHAIE
Keyword(s):  
Boron Nitride ◽  
Electric Field ◽  
Electric Field Gradient ◽  
Electronic Properties ◽  
Field Gradient ◽  
Active Sites ◽  
Density Functional ◽  
Functional Study ◽  
Significant Difference ◽  
Nqr Parameters

Density functional theory (DFT) study is performed to investigate the influence of carbon substituting in a representative model of armchair boron nitride nanotubes (BNNTs). To this aim, the electric field gradient (EFG) tensors at the sites of11B and11N nuclei are calculated in two models of (4,4) single-walled BNNT. Model one (raw) consists of 36 B and 36 N atoms with 12 saturating H atoms of two mouths while 7 B and 7 N atoms are substituted by 14 C atoms like a wire in model two ( C -substituted). The converted EFG tensors to measurable nuclear quadrupole resonance (NQR) parameters, quadrupole coupling constant (CQ) and asymmetry parameter (ηQ), reveal that the CQvalues in the length of raw BNNT are divided into some layers with equal magnitude and among them the mouth layers have the largest CQmagnitudes. In the C -substituted model, in addition to the mouth layers, the CQof those B and N nuclei directly bonded to C atoms are increased to the magnitudes as large as those mouth nuclei meaning that the active sites are increased in the C -substituted BNNT model. It is worth noting that the NQR parameters of other nuclei rather than those directly bonded to C and also those in the first neighborhood of C atoms are almost in equal values in the two models. Comparing the results with a recent study on zigzag BNNT (Mirzaei M et al., Z. Naturforsch A62:56, 2007) reveals that armchair and zigzag BNNTs show almost similar electronic properties. However, there is a significant difference in the electronic properties of those B and N atoms located at the mouth of the two BNNTs whose mouths are similar in armchair, whereas there are two different mouths ( B -mouth and N -mouth) in zigzag BNNT.

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