Papers by Javad Beheshtian
Journal of Molecular Modeling
Chemistry, an Asian journal, May 4, 2018
The authors found that XPS data for an incorrect sample were presented in Figure 3b, d, and einth... more The authors found that XPS data for an incorrect sample were presented in Figure 3b, d, and einthe original article. The correct spectra for Zn 0.94 Cd 0.06 ON Ps and Zn 0.94 Cd 0.06 O/rGO nanocomposites are presented below.The authors apologize for this mistake.
Structural Chemistry, 2017
We report adsorption energies, structures, energy gap (E g), charge transfer, and electronic prop... more We report adsorption energies, structures, energy gap (E g), charge transfer, and electronic properties of carbon monoxide (CO) on primary, cation Li-, Li-, and two Li-encapsulated fullerene-like beryllium oxide (B e 1
Applied Surface Science, 2016
Abstract First-principles calculations based on density functional theory were performed to study... more Abstract First-principles calculations based on density functional theory were performed to study the hydrogen adsorption and H 2 storage on the beryllium oxide nano-cage (BeONC). The adsorption of H 2 molecules on the nano-cage depends on the polarization and charge of the atom surface. The transfer of charge from the Be atom to its neighboring O atoms in the surface of the cluster indicates the ionic character of the Be O bond, so that Be O bonds are polarized. The results show that the H 2 molecule is significantly adsorbed on the BeONC surface, so that the H 2 prefers to be adsorbed atop a Be atom as compared to oxygen atoms of the cluster surface. Our calculations also reveal that the gravimetric uptake can overpass the value of 7.6 wt% with an average adsorbed energy ( E ads ) of −0.11 eV. These findings have important implications on designing of hydrogen storage materials and significantly broadening the spectrum of strategies for fabricating of new nanostructures to enhance hydrogen storage capacity.
The toxicity of lead associated with the lifecycle of perovskite solar cells (PSCs) is a serious ... more The toxicity of lead associated with the lifecycle of perovskite solar cells (PSCs) is a serious concern which may prove to be a major hurdle in the path toward their commercialization. The current proposed lead-free PSCs including Ag(I), Bi(III), Sb(III), Ti(IV), Ge(II), and Sn(II) low-toxicity cations are still plagued with the critical issues of poor stability and low efficiency. This is mainly because of their chemical stability. In the present research, utilization of all inorganic CsSnGeI3 based materials offers the advantages to enhance resistance of device to degradation, reduce the cost of cells, and minimize the carrier recombination. The presence of inorganic halide perovskite improves the photovoltaic parameters of PCSs via improved surface coverage and stability. The inverted structure of simulated devices using a 1D simulator like solar cell capacitance simulator (SCAPS) version 3308 involves TCOHTL/Perovskite/ETL/Au contact layer. PEDOT:PSS, PCBM, and CsSnGeI3 used as...
Journal of Molecular Modeling
The original article has been corrected. Publisher's note Springer Nature remains neutral with re... more The original article has been corrected. Publisher's note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Nanomaterials
We report a simple strategy to grow a novel cobalt nickel vanadium oxide (CoxNiVyOz) nanocomposit... more We report a simple strategy to grow a novel cobalt nickel vanadium oxide (CoxNiVyOz) nanocomposite on bare and reduced-graphene-oxide (rGO)-coated nickel foam (Ni foam) substrates. In this way, the synthesized graphene oxide is coated on Ni foam, and reduced electrochemically with a negative voltage to prepare a more conductive rGO-coated Ni foam substrate. The fabricated electrodes were characterized with a field-emission scanning electron microscope (FESEM), energy-dispersive X-ray spectra (EDX), X-ray photoelectron spectra (XPS), and Fourier-transform infrared (FTIR) spectra. The electrochemical performance of these CoxNiVyOz-based electrode materials deposited on rGO-coated Ni foam substrate exhibited superior specific capacitance 701.08 F/g, which is more than twice that of a sample coated on bare Ni foam (300.31 F/g) under the same experimental conditions at current density 2 A/g. Our work highlights the effect of covering the Ni foam surface with a rGO film to expedite the sp...
In this study, undoped ZnO, Fe and Mn doped ZnO nanostructures were synthesized by hydrothermal m... more In this study, undoped ZnO, Fe and Mn doped ZnO nanostructures were synthesized by hydrothermal method. The morphology of nanostructures was characterized by Scanning Electron Microscope. The electrochemical response of the carbon paste electrode modified with nanoparticles of ZnO and also ZnO doped with Fe and Mn toward levodopa (L-Dopa) was studied. Studies of cyclic voltammetry using provided modified electrode showed electro catalytic properties for electro-oxidation of L-Dopa, and a significant reduction in anodic over voltage compared to bare electrode was observed. Best response was obtained in terms of the current enhancement, overvoltage reduction, and reversibility improvement of the L-Dopa oxidation reaction under experimental conditions by modified electrode with zinc oxide nanoparticles doped with iron.
Applied Surface Science, 2021
Abstract The potential application of BN nanocone (BNNC) and AlN nanocone (AlNNC) as the anode ma... more Abstract The potential application of BN nanocone (BNNC) and AlN nanocone (AlNNC) as the anode material for the potassium-ion batteries (PIBs) was explored by means of the density functional theory calculations. The K cation adsorbed over the center of the apex ring of BNNC and AlNNC with the adsorption energies of -24.1 and -38.0 kcal/mol, respectively. While the K atom was physically adsorbed with a small adsorption energy. The maximum energy barrier which should be passed by the K cation to migrate over the surface of BNNC and AlNNC is 7.2 and 5.7 kcal/mol, respectively. These values are very small which yield a high ion mobility and quick charge/discharge rate. The minimum diffusion coefficient for K cation on the BNNC or AlNNC is computed to be 9.72 × 10-8 or 2.89 × 10-6 cm2/s. The cell voltage belonging to BNNC or AlNNC are nearly 0.90 or 1.47 V. We concluded that the AlNNC is a more promising anode material for PIB compared to the BNNC because of its higher voltage, ion mobility, and diffusion coefficient. By using diethyl ether as a solvent, the cell voltage is decreased by about 0.03 and 0.15 V in the case of BNNC and AlNNC, respectively.
Journal of Molecular Modeling, 2011
The thermodynamic and kinetic feasibility of H(2) dissociation on the BN, AlN, BP and AlP zigzag ... more The thermodynamic and kinetic feasibility of H(2) dissociation on the BN, AlN, BP and AlP zigzag nanotubes has been investigated theoretically by calculating the dissociation and activation energies. We determined the BN and AlP tubes to be inert toward H(2) dissociation, both thermodynamically and kinetically. The reactions are endothermic by 5.8 and 3 kcal mol(-1), exhibiting high activation energies of 38.8 and 30.6 kcal mol(-1), respectively. Our results indicated that H(2) dissociation is thermodynamically favorable on both PB and AlN nanotubes. However, in spite of the thermodynamic feasibility of H(2) dissociation on PB types, this process is kinetically unfavorable due to partly high activation energy. Generally, we concluded that among the four studied tubes, the AlN nanotube may be an appropriate model for H(2) dissociation process, from a thermodynamic and kinetic stand point. We also indicated that H(2) dissociation is not homolytic, rather it takes place via a heterolytic bond cleavage. In addition, a comparative study has been performed on the electrical and geometrical properties of the tubes. Our analysis showed that the electrical conductivity of tubes is as follows: BP>AlP>BN>AlN depending on how to combine the electron rich and electron poor atoms.
Journal of Molecular Modeling, 2012
Adsorption of arsenic ions, As (III and V), on the surface of fullerene-like B(12)N(12) cage has ... more Adsorption of arsenic ions, As (III and V), on the surface of fullerene-like B(12)N(12) cage has been explored in vacuum and aqueous phase using density functional theory in terms of Gibbs free energies, enthalpies, geometry, and density of state analysis. It was found that these ions can be strongly chemisorbed on the surface of the cluster in both vacuum and aqueous phase, resulting in significant changes in its electronic properties so that the cluster transforms from a semi-insulator to a semiconductor. The solvent significantly affects the geometry parameters and electronic properties of the As/B(12)N(12) complexes and the interaction between components is considerably weaker in the aqueous phase than that in the vacuum.
Materials Chemistry and Physics, 2021
Abstract The existence of defects in the graphene quantum dots can alter their electronic propert... more Abstract The existence of defects in the graphene quantum dots can alter their electronic properties. In this study, the interaction of sodium ion/atom with defected graphene quantum dots (dGQDs) of F3.Gr, F3H3.Gr, N3.Gr and N3H3.Gr as the anode material for the sodium ion batteries was investigated using density functional theory calculations. The amount of charge transfer from Na atom to F3H3.Gr and from F3.Gr to Na ion is about 0.23 and 0.94|e|, respectively. In the complex of Na atom with dGQDs as an n-type-adsorbed dGQD, the Fermi level shifts towards the higher energy and it can be facilitated charge transfer from Na atom to dGQDs. The estimated electrical conductivity for the complexes of Na atom with F3.Gr and F3H3.Gr is 6.51× 10-13 and 5.26× 10-12, respectively. This can result in a favorable condition in the processes of battery charge and discharge. The cell voltage belonging to F- doped defects or N- doped defects is nearly 1.54 - 1.58 V or 0.58 -0.61 V. It is concluded that the F- doped defects are more promising anode material for sodium ion batteries compared to N- doped defects because of their lower recovery time of adsorption, higher voltage, higher reactivity and better charge transfer.
Journal of Computational and Theoretical Nanoscience
RSC Advances
PSI (ψ)-graphene is a dynamically and thermally stable two-dimensional (2D) allotrope of carbon c... more PSI (ψ)-graphene is a dynamically and thermally stable two-dimensional (2D) allotrope of carbon composed of 5-6-7 carbon rings.
Physical Chemistry Chemical Physics
Double perovskite-based silver and bismuth Cs2AgBiX6 (X = Cl, Br, I) have shown a bright future f... more Double perovskite-based silver and bismuth Cs2AgBiX6 (X = Cl, Br, I) have shown a bright future for the development of low-risk photovoltaic devices due to their high stability and non-toxicity of their elements, unlike Pb-based perovskites.
Nanomaterials
Two-dimensional hexagonal boron nitride (hBN) is an insulator with polar covalent B-N bonds. Mono... more Two-dimensional hexagonal boron nitride (hBN) is an insulator with polar covalent B-N bonds. Monolayer and bilayer pentagonal BN emerge as an optoelectronic material, which can be used in photo-based devices such as photodetectors and photocatalysis. Herein, we implement spin polarized electron density calculations to extract electronic/optical properties of mono- and bilayer pentagonal BN structures, labeled as B 2 N 4 , B 3 N 3 , and B 4 N 2 . Unlike the insulating hBN, the pentagonal BN exhibits metallic or semiconducting behavior, depending on the detailed pentagonal structures. The origin of the metallicity is attributed to the delocalized boron (B) 2p electrons, which has been verified by electron localized function and electronic band structure as well as density of states. Interestingly, all 3D networks of different bilayer pentagonal BN are dynamically stable unlike 2D structures, whose monolayer B 4 N 2 is unstable. These 3D materials retain their metallic and semiconducto...
Materials Research Express
Proceedings of the Institution of Mechanical Engineers, Part L: Journal of Materials: Design and Applications
Calcium silicate hydrate (C–S–H) gel contains almost 50% to 70% of cement paste, which has a sign... more Calcium silicate hydrate (C–S–H) gel contains almost 50% to 70% of cement paste, which has a significant effect on the cement paste properties. An attempt is made to assess the atomistic structure of calcium silicate hydrate and the impact of water on it through molecular dynamics simulation. The most similar compositions (tobermorite 14Å, tobermorite 11Å, and jennite) are chosen and the effect of water thereof is studied. This study is presented in two phases: (1) water removal from the structure and simulating difference of water-to-calcium ratios through grand canonical Monte Carlo method. Next, the effect of water on the mechanical properties of C–S–H gel is examined through molecular dynamics method. (2) Defects in the existing molecular structures were introduced, which lead to newer Ca–Si proportions followed by the examination of the effect of water on the new structures. The obtained results revealed that as W/Ca ratio increases, the Young's modulus decreases. An increa...
Journal of Materials Science: Materials in Electronics
Water through nanochannels of graphene (G) exposes the capillary pressure, calling fundamental un... more Water through nanochannels of graphene (G) exposes the capillary pressure, calling fundamental understanding and predictive design of water within G nanochannels. Nanoconfinement induces switching behaviors at an atomic level, altering electronic and geometric structures. Herein, we study the single-layer water (SLW) and double-layer water (DLW) on monolayer G and encap-sulated in G layers and explore their diverse interfacial properties using a number of high level first principles calculations. By correlating the stability of adsorption, and interfacial properties such as intermediate pressure, charge transfer, structural deformation, one can decode various synergies in interaction properties of water on G nanocapillars. The external electric field (Eext) enhances polarization of system. More especially, changing the strength of Eext can effectively modulate the bandgap of monolayer G and bilayer graphene (BLG), and correspondingly causes a semimetal-semiconductor transition, i.e. Eg = 0.8 and 0.9 eV respectively. We also provide a comparison of phonon vibrational modes of water and heavy water (D2O) encapsulated within BLG, capturing their mobility as a key factor of separation mechanism. Moreover, we propose a nanocapacitor array of graphene-water-graphene composite, which electrodes has been separated by a water layer as a dielectric film. Nanometre-scale G capillaries open up a pathway to fabricate atomically channels walls for nanofluidic technology and nanocapacitor as a key device in integrated circuits (ICs).
Proceedings of The 16th International Electronic Conference on Synthetic Organic Chemistry
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Papers by Javad Beheshtian