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Author Sobrino Fernandez, M.M.; Neek-Amal, M.; Peeters, F.M.
Title (up) AA-stacked bilayer square ice between graphene layers Type A1 Journal article
Year 2015 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 92 Issue 92 Pages 245428
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Water confined between two graphene layers with a separation of a few A forms a layered two-dimensional ice structure. Using large scale molecular dynamics simulations with the adoptable ReaxFF interatomic potential we found that flat monolayer ice with a rhombic-square structure nucleates between the graphene layers which is nonpolar and nonferroelectric. We provide different energetic considerations and H-bonding results that explain the interlayer and intralayer properties of two-dimensional ice. The controversial AA stacking found experimentally [Algara-Siller et al., Nature (London) 519, 443 (2015)] is consistent with our minimum-energy crystal structure of bilayer ice. Furthermore, we predict that an odd number of layers of ice has the same lattice structure as monolayer ice, while an even number of ice layers exhibits the square ice AA stacking of bilayer ice.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000366731800004 Publication Date 2015-12-17
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121; 1550-235x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 40 Open Access
Notes ; This work was supported by the ESF-Eurographene project CONGRAN, and the Flemish Science Foundation (FWO-Vl). ; Approved Most recent IF: 3.836; 2015 IF: 3.736
Call Number c:irua:130203 Serial 4127
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Author Hamid, I.; Jalali, H.; Peeters, F.M.; Neek-Amal, M.
Title (up) Abnormal in-plane permittivity and ferroelectricity of confined water : from sub-nanometer channels to bulk Type A1 Journal article
Year 2021 Publication Journal Of Chemical Physics Abbreviated Journal J Chem Phys
Volume 154 Issue 11 Pages 114503
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Dielectric properties of nano-confined water are important in several areas of science, i.e., it is relevant in the dielectric double layer that exists in practically all heterogeneous fluid-based systems. Molecular dynamics simulations are used to predict the in-plane dielectric properties of confined water in planar channels of width ranging from sub-nanometer to bulk. Because of suppressed rotational degrees of freedom near the confining walls, the dipole of the water molecules tends to be aligned parallel to the walls, which results in a strongly enhanced in-plane dielectric constant (epsilon (parallel to)) reaching values of about 120 for channels with height 8 angstrom < h < 10 angstrom. With the increase in the width of the channel, we predict that epsilon (parallel to) decreases nonlinearly and reaches the bulk value for h > 70 angstrom. A stratified continuum model is proposed that reproduces the h > 10 angstrom dependence of epsilon (parallel to). For sub-nanometer height channels, abnormal behavior of epsilon (parallel to) is found with two orders of magnitude reduction of epsilon (parallel to) around h similar to 7.5 angstrom, which is attributed to the formation of a particular ice phase that exhibits long-time (similar to mu s) stable ferroelectricity. This is of particular importance for the understanding of the influence of confined water on the functioning of biological systems.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000629831900001 Publication Date 2021-03-17
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0021-9606 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.965 Times cited 9 Open Access OpenAccess
Notes Approved Most recent IF: 2.965
Call Number UA @ admin @ c:irua:177579 Serial 6967
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Author Ackerman, M.L.; Kumar, P.; Neek-Amal, M.; Thibado, P.M.; Peeters, F.M.; Singh, S.
Title (up) Anomalous dynamical behavior of freestanding graphene membranes Type A1 Journal article
Year 2016 Publication Physical review letters Abbreviated Journal Phys Rev Lett
Volume 117 Issue 117 Pages 126801
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We report subnanometer, high-bandwidth measurements of the out-of-plane (vertical) motion of atoms in freestanding graphene using scanning tunneling microscopy. By tracking the vertical position over a long time period, a 1000-fold increase in the ability to measure space-time dynamics of atomically thin membranes is achieved over the current state-of-the-art imaging technologies. We observe that the vertical motion of a graphene membrane exhibits rare long-scale excursions characterized by both anomalous mean-squared displacements and Cauchy-Lorentz power law jump distributions.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000383171800010 Publication Date 2016-09-13
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0031-9007 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 8.462 Times cited 46 Open Access
Notes ; The authors thank Theodore L. Einstein, Michael F. Shlesinger, and Woodrow L. Shew for their careful reading of the manuscript and insightful comments. This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem Foundation of the Flemish Government. P. M. T. was supported by the Office of Naval Research under Grant No. N00014-10-1-0181 and the National Science Foundation under Grant No. DMR-0855358. M.N.-A. was supported by Iran Science Elites Federation (ISEF) under Grant No. 11/66332. ; Approved Most recent IF: 8.462
Call Number UA @ lucian @ c:irua:137125 Serial 4347
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Author Neek-Amal, M.; Beheshtian, J.; Sadeghi, A.; Michel, K.H.; Peeters, F.M.
Title (up) Boron nitride mono layer : a strain-tunable nanosensor Type A1 Journal article
Year 2013 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C
Volume 117 Issue 25 Pages 13261-13267
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract The influence of triaxial in-plane strain on the electronic properties of a hexagonal boron-nitride sheet is investigated using density functional theory. Different from graphene, the triaxial strain localizes the molecular orbitals of the boron-nitride flake in its center depending on the direction of the applied strain. The proposed technique for localizing the molecular orbitals that are close to the Fermi level in the center of boron nitride flakes can be used to actualize engineered nanosensors, for instance, to selectively detect gas molecules. We show that the central part of the strained flake adsorbs polar molecules more strongly as compared with an unstrained sheet.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000321236400041 Publication Date 2013-06-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-7447;1932-7455; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.536 Times cited 38 Open Access
Notes ; This work was supported by the EU-Marie Curie IIF postdoc Fellowship/299855 (for M.N.-A.), the ESF EuroGRAPHENE project CONGRAN, the Flemish Science Foundation (FWO-VI), and the Methusalem Funding of the Flemish government. AS. would like to thank the Universiteit Antwerpen for its hospitality. ; Approved Most recent IF: 4.536; 2013 IF: 4.835
Call Number UA @ lucian @ c:irua:109829 Serial 249
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Author Villarreal, R.; Lin, P.-C.; Faraji, F.; Hassani, N.; Bana, H.; Zarkua, Z.; Nair, M.N.; Tsai, H.-C.; Auge, M.; Junge, F.; Hofsaess, H.C.; De Gendt, S.; De Feyter, S.; Brems, S.; Ahlgren, E.H.; Neyts, E.C.; Covaci, L.; Peeters, F.M.; Neek-Amal, M.; Pereira, L.M.C.
Title (up) Breakdown of universal scaling for nanometer-sized bubbles in graphene Type A1 Journal article
Year 2021 Publication Nano Letters Abbreviated Journal Nano Lett
Volume 21 Issue 19 Pages 8103-8110
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract We report the formation of nanobubbles on graphene with a radius of the order of 1 nm, using ultralow energy implantation of noble gas ions (He, Ne, Ar) into graphene grown on a Pt(111) surface. We show that the universal scaling of the aspect ratio, which has previously been established for larger bubbles, breaks down when the bubble radius approaches 1 nm, resulting in much larger aspect ratios. Moreover, we observe that the bubble stability and aspect ratio depend on the substrate onto which the graphene is grown (bubbles are stable for Pt but not for Cu) and trapped element. We interpret these dependencies in terms of the atomic compressibility of the noble gas as well as of the adhesion energies between graphene, the substrate, and trapped atoms.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000709549100026 Publication Date 2021-09-14
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1530-6984 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 12.712 Times cited 12 Open Access OpenAccess
Notes Approved Most recent IF: 12.712
Call Number UA @ admin @ c:irua:184137 Serial 6857
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Author Neek-Amal, M.; Peeters, F.M.
Title (up) Buckled circular monolayer graphene : a graphene nano-bowl Type A1 Journal article
Year 2011 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat
Volume 23 Issue 4 Pages 045002-045002,8
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We investigate the stability of circular monolayer graphene subjected to a radial load using non-equilibrium molecular dynamics simulations. When monolayer graphene is radially stressed, after some small circular strain (~0.4%) it buckles and bends into a new bowl-like shape. Young's modulus is calculated from the linear relation between stress and strain before the buckling threshold, which is in agreement with experimental results. The prediction of elasticity theory for the buckling threshold of a radially stressed plate is presented and its results are compared to the one of our atomistic simulation. The Jarzynski equality is used to estimate the difference between the free energy of the non-compressed states and the buckled states. From a calculation of the free energy we obtain the optimum radius for which the system feels the minimum boundary stress.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000286142800003 Publication Date 2010-12-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0953-8984;1361-648X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.649 Times cited 27 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Belgian Science Policy (IAP). ; Approved Most recent IF: 2.649; 2011 IF: 2.546
Call Number UA @ lucian @ c:irua:88043 Serial 259
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Author Faraji, F.; Neek-Amal, M.; Neyts, E.C.; Peeters, F.M.
Title (up) Cation-controlled permeation of charged polymers through nanocapillaries Type A1 Journal article
Year 2023 Publication Physical review E Abbreviated Journal Phys Rev E
Volume 107 Issue 3 Pages 034501-34510
Keywords A1 Journal article; Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Molecular dynamics simulations are used to study the effects of different cations on the permeation of charged polymers through flat capillaries with heights below 2 nm. Interestingly, we found that, despite being monovalent, Li+ , Na+ , and K+ cations have different effects on polymer permeation, which consequently affects their transmission speed throughout those capillaries. We attribute this phenomenon to the interplay of the cations' hydration free energies and the hydrodynamic drag in front of the polymer when it enters the capillary. Different alkali cations exhibit different surface versus bulk preferences in small clusters of water under the influence of an external electric field. This paper presents a tool to control the speed of charged polymers in confined spaces using cations.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000955986000006 Publication Date 2023-03-17
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2470-0053 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.4 Times cited Open Access Not_Open_Access
Notes Approved Most recent IF: 2.4; 2023 IF: 2.366
Call Number UA @ admin @ c:irua:196089 Serial 7586
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Author Hassani, N.; Yagmurcukardes, M.; Peeters, F.M.; Neek-Amal, M.
Title (up) Chlorinated phosphorene for energy application Type A1 Journal article
Year 2024 Publication Computational materials science Abbreviated Journal
Volume 231 Issue Pages 112625-112628
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The influence of decoration with impurities and the composition dependent band gap in 2D materials has been the subject of debate for a long time. Here, by using Density Functional Theory (DFT) calculations, we systematically disclose physical properties of chlorinated phosphorene having the stoichiometry of PmCln. By analyzing the adsorption energy, charge density, migration energy barrier, structural, vibrational, and electronic properties of chlorinated phosphorene, we found that (I) the Cl-P bonds are strong with binding energy Eb =-1.61 eV, decreases with increasing n. (II) Cl atoms on phosphorene have anionic feature, (III) the migration path of Cl on phosphorene is anisotropic with an energy barrier of 0.38 eV, (IV) the phonon band dispersion reveal that chlorinated phosphorenes are stable when r <= 0.25 where r = m/n, (V) chlorinated phosphorenes is found to be a photonic crystal in the frequency range of 280 cm-1 to 325 cm-1, (VI) electronic band structure of chlorinated phosphorenes exhibits quasi-flat bands emerging around the Fermi level with widths in the range of 22 meV to 580 meV, and (VII) Cl adsorption causes a semiconducting to metallic/semi-metallic transition which makes it suitable for application as an electroactive material. To elucidate this application, we investigated the change in binding energy (Eb), specific capacity, and open-circuit voltage as a function of the density of adsorbed Cl. The theoretical storage capacity of the chlorinated phosphorene is found to be 168.19 mA h g-1with a large average voltage (similar to 2.08 V) which is ideal number as a cathode in chloride-ion batteries.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001110003400001 Publication Date 2023-11-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0927-0256 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access Not_Open_Access
Notes Approved no
Call Number UA @ admin @ c:irua:202125 Serial 9008
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Author Javdani, Z.; Hassani, N.; Faraji, F.; Zhou, R.; Sun, C.; Radha, B.; Neyts, E.; Peeters, F.M.; Neek-Amal, M.
Title (up) Clogging and unclogging of hydrocarbon-contaminated nanochannels Type A1 Journal article
Year 2022 Publication The journal of physical chemistry letters Abbreviated Journal J Phys Chem Lett
Volume 13 Issue 49 Pages 11454-11463
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract The recent advantages of the fabrication of artificial nanochannels enabled new research on the molecular transport, permeance, and selectivity of various gases and molecules. However, the physisorption/chemisorption of the unwanted molecules (usually hydrocarbons) inside nanochannels results in the alteration of the functionality of the nanochannels. We investigated contamination due to hydrocarbon molecules, nanochannels made of graphene, hexagonal boron nitride, BC2N, and molybdenum disulfide using molecular dynamics simulations. We found that for a certain size of nanochannel (i.e., h = 0.7 nm), as a result of the anomalous hydrophilic nature of nanochannels made of graphene, the hydrocarbons are fully adsorbed in the nanochannel, giving rise to full uptake. An increasing temperature plays an important role in unclogging, while pressure does not have a significant role. The results of our pioneering work contribute to a better understanding and highlight the important factors in alleviating the contamination and unclogging of nanochannels, which are in good agreement with the results of recent experiments.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000893147700001 Publication Date 2022-12-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1948-7185 ISBN Additional Links UA library record; WoS full record
Impact Factor 5.7 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 5.7
Call Number UA @ admin @ c:irua:192815 Serial 7263
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Author Neek-Amal, M.; Peeters, F.M.; Grigorieva, I.V.; Geim, A.K.
Title (up) Commensurability Effects in Viscosity of Nanoconfined Water Type A1 Journal article
Year 2016 Publication ACS nano Abbreviated Journal Acs Nano
Volume 10 Issue 10 Pages 3685-3692
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract The rate of water flow through hydrophobic nanocapillaries is greatly enhanced as compared to that expected from macroscopic hydrodynamics. This phenomenon is usually described in terms of a relatively large slip length, which is in turn defined by such microscopic properties as the friction between water and capillary surfaces and the viscosity of water. We show that the viscosity of water and, therefore, its flow rate are profoundly affected by the layered structure of confined water if the capillary size becomes less than 2 nm. To this end, we study the structure and dynamics of water confined between two parallel graphene layers using equilibrium molecular dynamics simulations. We find that the shear viscosity is not only greatly enhanced for subnanometer capillaries, but also exhibits large oscillations that originate from commensurability between the capillary size and the size of water molecules. Such oscillating behavior of viscosity and, consequently, the slip length should be taken into account in designing and studying graphene-based and similar membranes for desalination and filtration.
Address School of Physics and Astronomy, University of Manchester , Manchester M13 9PL, United Kingdom
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Wos 000372855400073 Publication Date 2016-02-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1936-0851 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 13.942 Times cited 160 Open Access
Notes ; M.N.A. was support by Shahid Rajaee Teacher Training University under contract number 29605. ; Approved Most recent IF: 13.942
Call Number c:irua:133237 Serial 4012
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Author Neek-Amal, M.; Peeters, F.M.
Title (up) Defected graphene nanoribbons under axial compression Type A1 Journal article
Year 2010 Publication Applied physics letters Abbreviated Journal Appl Phys Lett
Volume 97 Issue 15 Pages 153118,1-153118,3
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The buckling of defected rectangular graphene nanoribbons when subjected to axial stress with supported boundary conditions is investigated using atomistic simulations. The buckling strain and mechanical stiffness of monolayer graphene decrease with the percentage of randomly distributed vacancies. The elasticity to plasticity transition in the stress-strain curve, at low percentage of vacancies, are found to be almost equal to the buckling strain thresholds and they decrease with increasing percentage of vacancies.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000283216900069 Publication Date 2010-10-14
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0003-6951; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.411 Times cited 43 Open Access
Notes ; This work was supported by the Flemish Science Foundation (WO-Vl) and the Belgian Science Policy (IAP) ; Approved Most recent IF: 3.411; 2010 IF: 3.841
Call Number UA @ lucian @ c:irua:85789 Serial 624
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Author Ghorbanfekr-Kalashami, H.; Vasu, K.S.; Nair, R.R.; Peeters, F.M.; Neek-Amal, M.
Title (up) Dependence of the shape of graphene nanobubbles on trapped substance Type A1 Journal article
Year 2017 Publication Nature communications Abbreviated Journal Nat Commun
Volume 8 Issue 8 Pages 15844
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract Van der Waals (vdW) interaction between two-dimensional crystals (2D) can trap substances in high pressurized (of order 1 GPa) on nanobubbles. Increasing the adhesion between the 2D crystals further enhances the pressure and can lead to a phase transition of the trapped material. We found that the shape of the nanobubble can depend critically on the properties of the trapped substance. In the absence of any residual strain in the top 2D crystal, flat nanobubbles can be formed by trapped long hydrocarbons (that is, hexadecane). For large nanobubbles with radius 130 nm, our atomic force microscopy measurements show nanobubbles filled with hydrocarbons (water) have a cylindrical symmetry (asymmetric) shape which is in good agreement with our molecular dynamics simulations. This study provides insights into the effects of the specific material and the vdW pressure on the microscopic details of graphene bubbles.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000403417500001 Publication Date 2017-06-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2041-1723 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 12.124 Times cited 44 Open Access
Notes We acknowledge fruitful discussion with Irina Grigorieva and Andre K. Geim. This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem program, the Royal Society and the Engineering and Physical Sciences Research Council, UK (EP/K016946/1). M.N.-A. was supported by Iran National Science Foundation (INSF). Approved Most recent IF: 12.124
Call Number CMT @ cmt @ c:irua:144189 Serial 4580
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Author Sadeghi, A.; Neek-Amal, M.; Berdiyorov, G.R.; Peeters, F.M.
Title (up) Diffusion of fluorine on and between graphene layers Type A1 Journal article
Year 2015 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 91 Issue 91 Pages 014304
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Using first-principles calculations and reactive force field molecular dynamics simulations, we study the structural properties and dynamics of a fluorine (F) atom, either adsorbed on the surface of single layer graphene (F/GE) or between the layers of AB stacked bilayer graphene (F@ bilayer graphene). It is found that the diffusion of the F atom is very different in those cases, and that the mobility of the F atom increases by about an order of magnitude when inserted between two graphene layers. The obtained diffusion constant for F/GE is twice larger than that experimentally found for gold adatom and theoretically found for C-60 molecule on graphene. Our study provides important physical insights into the dynamics of fluorine atoms between and on graphene layers and explains the mechanism behind the separation of graphite layers due to intercalation of F atoms.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000349125800002 Publication Date 2015-01-08
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121; 1550-235x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 15 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-VI) and the Methusalem Foundation of the Flemish Government. ; Approved Most recent IF: 3.836; 2015 IF: 3.736
Call Number UA @ lucian @ c:irua:132561 Serial 4161
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Author Seyed-Talebi, S.M.; Beheshtian, J.; Neek-Amal, M.
Title (up) Doping effect on the adsorption of NH3 molecule onto graphene quantum dot : from the physisorption to the chemisorption Type A1 Journal article
Year 2013 Publication Journal of applied physics Abbreviated Journal J Appl Phys
Volume 114 Issue 12 Pages 124307-7
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The adsorption of ammonia molecule onto a graphene hexagonal flake, aluminum (Al) and boron (B) doped graphene flakes (graphene quantum dots, GQDs) are investigated using density functional theory. We found that NH3 molecule is absorbed to the hollow site through the physisorption mechanism without altering the electronic properties of GQD. However, the adsorption energy of NH3 molecule onto the Al- and B-doped GQDs increases with respect GQD resulting chemisorption. The adsorption of NH3 onto the Al-doped and B-doped GQDs makes graphene locally buckled, i.e., B-doped and Al-doped GQDs are not planar. The adsorption mechanism onto a GQD is different than that of graphene. This study reveals important features of the edge passivation and doping effects of the adsorption mechanism of external molecules onto the graphene quantum dots. (C) 2013 AIP Publishing LLC.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000325391100057 Publication Date 2013-09-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0021-8979; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.068 Times cited 10 Open Access
Notes ; This work was supported by the EU-Marie Curie IIF Fellowship/299855 for M.-N.A. ; Approved Most recent IF: 2.068; 2013 IF: 2.185
Call Number UA @ lucian @ c:irua:112201 Serial 750
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Author Neek-Amal, M.; Peeters, F.M.
Title (up) Effect of grain boundary on the buckling of graphene nanoribbons Type A1 Journal article
Year 2012 Publication Applied physics letters Abbreviated Journal Appl Phys Lett
Volume 100 Issue 10 Pages 101905-101905,4
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The buckling of graphene nano-ribbons containing a grain boundary is studied using atomistic simulations where free and supported boundary conditions are invoked. We consider the buckling transition of two kinds of grain boundaries with special symmetry. When graphene contains a large angle grain boundary with theta = 21.8 degrees, the buckling strains are larger than those of perfect graphene when the ribbons with free (supported) boundary condition are subjected to compressive tension parallel (perpendicular) to the grain boundary. This is opposite for the results of theta = 32.2 degrees. The shape of the deformations of the buckled graphene nanoribbons depends on the boundary conditions, the presence of the particular used grain boundaries, and the direction of applied in-plane compressive tension. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.3692573]
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000301655500021 Publication Date 2012-03-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0003-6951; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.411 Times cited 18 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Belgian Science Policy (IAP). ; Approved Most recent IF: 3.411; 2012 IF: 3.794
Call Number UA @ lucian @ c:irua:97794 Serial 809
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Author Neek-Amal, M.; Rashidi, R.; Nair, R.R.; Neilson, D.; Peeters, F.M.
Title (up) Electric-field-induced emergent electrical connectivity in graphene oxide Type A1 Journal article
Year 2019 Publication Physical review B Abbreviated Journal Phys Rev B
Volume 99 Issue 11 Pages 115425
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Understanding the appearance of local electrical connectivity in liquid filled layered graphene oxide subjected to an external electric field is important to design electrically controlled smart permeable devices and also to gain insight into the physics behind electrical effects on confined water permeation. Motivated by recent experiments [K. G. Zhou et al. Nature (London) 559, 236 (2018)], we introduce a new model with random percolating paths for electrical connectivity in micron thick water filled layered graphene oxide, which mimics parallel resistors connected across the top and bottom electrodes. We find that a strong nonuniform radial electric field of the order similar to 10-50 mV/nm can be induced between layers depending on the current flow through the formed conducting paths. The maxima of the induced fields are not necessarily close to the electrodes and may be localized in the middle region of the layered material. The emergence of electrical connectivity and the associated electrical effects have a strong influence on the surrounding fluid in terms of ionization and wetting which subsequently determines the permeation properties.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000461960100001 Publication Date 2019-03-19
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2469-9969; 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 3 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem program. ; Approved Most recent IF: 3.836
Call Number UA @ admin @ c:irua:158534 Serial 5206
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Author Fernandez, M.S.; Peeters, F.M.; Neek-Amal, M.
Title (up) Electric-field-induced structural changes in water confined between two graphene layers Type A1 Journal article
Year 2016 Publication Physical review B Abbreviated Journal Phys Rev B
Volume 94 Issue 4 Pages 045436
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract An external electric field changes the physical properties of polar liquids due to the reorientation of their permanent dipoles. Using molecular dynamics simulations, we predict that an in-plane electric field applied parallel to the channel polarizes water molecules which are confined between two graphene layers, resulting in distinct ferroelectricity and electrical hysteresis. We found that electric fields alter the in-plane order of the hydrogen bonds: Reversing the electric field does not restore the system to the nonpolar initial state, instead a residual dipole moment remains in the system. The square-rhombic structure of 2D ice is transformed into two rhombic-rhombic structures. Our study provides insights into the ferroelectric state of water when confined in nanochannels and shows how this can be tuned by an electric field.
Address
Corporate Author Thesis
Publisher American Physical Society Place of Publication New York, N.Y Editor
Language Wos 000381485200005 Publication Date 2016-07-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2469-9969; 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 31 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. ; Approved Most recent IF: 3.836
Call Number UA @ lucian @ c:irua:144684 Serial 4649
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Author Zhou, K.-G.; Vasu, K.S.; Cherian, C.T.; Neek-Amal, M.; Zhang, J.C.; Ghorbanfekr-Kalashami, H.; Huang, K.; Marshall, O.P.; Kravets, V.G.; Abraham, J.; Su, Y.; Grigorenko, A.N.; Pratt, A.; Geim, A.K.; Peeters, F.M.; Novoselov, K.S.; Nair, R.R.
Title (up) Electrically controlled water permeation through graphene oxide membranes Type A1 Journal article
Year 2018 Publication Nature Abbreviated Journal Nature
Volume 559 Issue 7713 Pages 236-+
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract Controlled transport of water molecules through membranes and capillaries is important in areas as diverse as water purification and healthcare technologies(1-7). Previous attempts to control water permeation through membranes (mainly polymeric ones) have concentrated on modulating the structure of the membrane and the physicochemical properties of its surface by varying the pH, temperature or ionic strength(3,8). Electrical control over water transport is an attractive alternative; however, theory and simulations(9-14) have often yielded conflicting results, from freezing of water molecules to melting of ice(14-16) under an applied electric field. Here we report electrically controlled water permeation through micrometre-thick graphene oxide membranes(17-21). Such membranes have previously been shown to exhibit ultrafast permeation of water(17,22) and molecular sieving properties(18,21), with the potential for industrial-scale production. To achieve electrical control over water permeation, we create conductive filaments in the graphene oxide membranes via controllable electrical breakdown. The electric field that concentrates around these current-carrying filaments ionizes water molecules inside graphene capillaries within the graphene oxide membranes, which impedes water transport. We thus demonstrate precise control of water permeation, from ultrafast permeation to complete blocking. Our work opens up an avenue for developing smart membrane technologies for artificial biological systems, tissue engineering and filtration.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000438240900052 Publication Date 2018-07-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0028-0836 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 40.137 Times cited 216 Open Access
Notes ; This work was supported by the Royal Society, Engineering and Physical Sciences Research Council, UK (EP/K016946/1, EP/N013670/1 and EP/P00119X/1), British Council (award reference number 279336045), European Research Council (contract 679689) and Lloyd's Register Foundation. We thank J. Waters for assisting with X-ray measurements and G. Yu for electrical measurements. ; Approved Most recent IF: 40.137
Call Number UA @ lucian @ c:irua:152420UA @ admin @ c:irua:152420 Serial 5096
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Author Singh, S.K.; Neek-Amal, M.; Peeters, F.M.
Title (up) Electronic properties of graphene nano-flakes : energy gap, permanent dipole, termination effect, and Raman spectroscopy Type A1 Journal article
Year 2014 Publication The journal of chemical physics Abbreviated Journal J Chem Phys
Volume 140 Issue 7 Pages 074304-74309
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The electronic properties of graphene nano-flakes (GNFs) with different edge passivation are investigated by using density functional theory. Passivation with F and H atoms is considered: C-Nc X-Nx (X = F or H). We studied GNFs with 10 < N-c < 56 and limit ourselves to the lowest energy configurations. We found that: (i) the energy difference Delta between the highest occupied molecular orbital and the lowest unoccupied molecular orbital decreases with N-c, (ii) topological defects (pentagon and heptagon) break the symmetry of the GNFs and enhance the electric polarization, (iii) the mutual interaction of bilayer GNFs can be understood by dipole-dipole interaction which were found sensitive to the relative orientation of the GNFs, (iv) the permanent dipoles depend on the edge terminated atom, while the energy gap is independent of it, and (v) the presence of heptagon and pentagon defects in the GNFs results in the largest difference between the energy of the spin-up and spin-down electrons which is larger for the H-passivated GNFs as compared to F-passivated GNFs. Our study shows clearly the effect of geometry, size, termination, and bilayer on the electronic properties of small GNFs. This study reveals important features of graphene nano-flakes which can be detected using Raman spectroscopy. (C) 2014 AIP Publishing LLC.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000332039900020 Publication Date 2014-02-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0021-9606;1089-7690; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.965 Times cited 30 Open Access
Notes ; This work was supported by the EU-Marie Curie IIF postdoctoral Fellowship/ 299855 (for M. N.-A.), the ESF-EuroGRAPHENE project CONGRAN, the Flemish Science Foundation (FWO-Vl), and the Methusalem Foundation of the Flemish Government. ; Approved Most recent IF: 2.965; 2014 IF: 2.952
Call Number UA @ lucian @ c:irua:115857 Serial 1002
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Author Alihosseini, M.; Ghasemi, S.; Ahmadkhani, S.; Alidoosti, M.; Esfahani, D.N.; Peeters, F.M.; Neek-Amal, M.
Title (up) Electronic properties of oxidized graphene : effects of strain and an electric field on flat bands and the energy gap Type A1 Journal article
Year 2021 Publication The journal of physical chemistry letters Abbreviated Journal J Phys Chem Lett
Volume Issue Pages
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract A multiscale modeling and simulation approach, including first-principles calculations, ab initio molecular dynamics simulations, and a tight binding approach, is employed to study band flattening of the electronic band structure of oxidized monolayer graphene. The width offlat bands can be tuned by strain, the external electric field, and the density of functional groups and their distribution. A transition to a conducting state is found for monolayer graphene with impurities when it is subjected to an electric field of similar to 1.0 V/angstrom. Several parallel impurity-induced flat bands appear in the low-energy spectrum of monolayer graphene when the number of epoxy groups is changed. The width of the flat band decreases with an increase in tensile strain but is independent of the electric field strength. Here an alternative and easy route for obtaining band flattening in thermodynamically stable functionalized monolayer graphene is introduced. Our work discloses a new avenue for research on band flattening in monolayer graphene.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000737988100001 Publication Date 2021-12-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1948-7185 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 9.353 Times cited 1 Open Access Not_Open_Access
Notes Approved Most recent IF: 9.353
Call Number UA @ admin @ c:irua:184725 Serial 6987
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Author Neek-Amal, M.; Covaci, L.; Shakouri, K.; Peeters, F.M.
Title (up) Electronic structure of a hexagonal graphene flake subjected to triaxial stress Type A1 Journal article
Year 2013 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 88 Issue 11 Pages 115428
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The electronic properties of a triaxially strained hexagonal graphene flake with either armchair or zigzag edges are investigated using molecular dynamics simulations and tight-binding calculations. We found that (i) the pseudomagnetic field in strained graphene flakes is not uniform neither in the center nor at the edge of zigzag terminated flakes, (ii) the pseudomagnetic field is almost zero in the center of armchair terminated flakes but increases dramatically near the edges, (iii) the pseudomagnetic field increases linearly with strain, for strains lower than 15% but increases nonlinearly beyond it, (iv) the local density of states in the center of the zigzag hexagon exhibits pseudo-Landau levels with broken sublattice symmetry in the zeroth pseudo-Landau level, and in addition there is a shift in the Dirac cone due to strain induced scalar potentials, and (v) there is size effect in pseudomagnetic field. This study provides a realistic model of the electronic properties of inhomogeneously strained graphene where the relaxation of the atomic positions is correctly included together with strain induced modifications of the hopping terms up to next-nearest neighbors.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000324690400008 Publication Date 2013-09-24
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 46 Open Access
Notes ; This work was supported by the EU-Marie Curie IIF postdoctoral Fellowship/ 299855 (for M.N.-A.), the ESF EuroGRAPHENE project CONGRAN, the Flemish Science Foundation (FWO-Vl) and the Methusalem Funding of the Flemish government. ; Approved Most recent IF: 3.836; 2013 IF: 3.664
Call Number UA @ lucian @ c:irua:111168 Serial 1011
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Author de Aquino, B.R.H.; Ghorbanfekr-Kalashami, H.; Neek-Amal, M.; Peeters, F.M.
Title (up) Electrostrictive behavior of confined water subjected to GPa pressure Type A1 Journal article
Year 2018 Publication Physical review B Abbreviated Journal Phys Rev B
Volume 97 Issue 14 Pages 144111
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Water inside a nanocapillary exhibits unconventional structural and dynamical behavior due to its ordered structure. The confining walls, density, and lateral pressures control profoundly the microscopic structure of trapped water. Here we study the electrostriction of confined water subjected to pressures of the order of GPa for two different setups: (i) a graphene nanochannel containing a constant number of water molecules independent of the height of the channel, (ii) an open nanochannel where water molecules can be exchanged with those in a reservoir. For the former case, a square-rhombic structure of confined water is formed when the height of the channel is d = 6.5 angstrom having a density of rho = 1.42 g cm(-3). By increasing the height of the channel, a transition from a flat to a buckled state occurs, whereas the density rapidly decreases and reaches the bulk density for d congruent to 8.5 angstrom. When a perpendicular electric field is applied, the water structure and the lateral pressure change. For strong electric fields (similar to 1 V/angstrom), the square-rhombic structure is destroyed. For an open setup, a solid phase of confined water consisting of an imperfect square-rhombic structure is formed. By applying a perpendicular field, the density and phase of confined water change. However, the density and pressure inside the channel decrease as compared to the first setup. Our study is closely related to recent experiments on confined water, and it reveals the sensitivity of the microscopic structure of confined water to the size of the channel, the external electric field, and the experimental setup.
Address
Corporate Author Thesis
Publisher American Physical Society Place of Publication New York, N.Y Editor
Language Wos 000430809300002 Publication Date 2018-04-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2469-9969; 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 6 Open Access
Notes ; This work was supported by the Fund for Scientific Research-Flanders (FWO-Vl) and the Methusalem programe. ; Approved Most recent IF: 3.836
Call Number UA @ lucian @ c:irua:151574UA @ admin @ c:irua:151574 Serial 5023
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Author Neek-Amal, M.; Peeters, F.M.
Title (up) Graphene nanoribbons subjected to axial stress Type A1 Journal article
Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 82 Issue 8 Pages 085432-085432,6
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Atomistic simulations are used to study the bending of rectangular graphene nanoribbons subjected to axial stress both for free boundary and supported boundary conditions. The shapes of the deformations of the buckled graphene nanoribbons, for small values of the stress, are sine waves where the number of nodal lines depend on the longitudinal size of the system and the applied boundary condition. The buckling strain for the supported boundary condition is found to be independent of the longitudinal size and estimated to be 0.86%. From a calculation of the free energy at finite temperature we find that the equilibrium projected two-dimensional area of the graphene nanoribbon is less than the area of a flat sheet. At the optimum length the boundary strain for the supported boundary condition is 0.48%.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000281065100007 Publication Date 2010-08-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 92 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Belgian Science Policy (IAP). ; Approved Most recent IF: 3.836; 2010 IF: 3.774
Call Number UA @ lucian @ c:irua:84583 Serial 1373
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Author Neek-Amal, M.; Peeters, F.M.
Title (up) Graphene on boron-nitride : Moiré pattern in the van der Waals energy Type A1 Journal article
Year 2014 Publication Applied physics letters Abbreviated Journal Appl Phys Lett
Volume 104 Issue 4 Pages 041909-4
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The spatial dependence of the van der Waals (vdW) energy between graphene and hexagonal boron-nitride (h-BN) is investigated using atomistic simulations. The van der Waals energy between graphene and h-BN shows a hexagonal superlattice structure identical to the observed Moire pattern in the local density of states, which depends on the lattice mismatch and misorientation angle between graphene and h-BN. Our results provide atomistic features of the weak van der Waals interaction between graphene and BN which are in agreement with experiment and provide an analytical expression for the size of the spatial variation of the weak van der Waals interaction. We also found that the A-B-lattice symmetry of graphene is broken along the armchair direction. (C) 2014 AIP Publishing LLC.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000331209900028 Publication Date 2014-01-31
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0003-6951;1077-3118; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.411 Times cited 61 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem Foundation of the Flemish Government. M.N.-A was supported by the EU-Marie Curie IIF postdoctoral Fellowship/299855. ; Approved Most recent IF: 3.411; 2014 IF: 3.302
Call Number UA @ lucian @ c:irua:115802 Serial 1374
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Author Neek-Amal, M.; Peeters, F.M.
Title (up) Graphene on hexagonal lattice substrate : stress and pseudo-magnetic field Type A1 Journal article
Year 2014 Publication Applied physics letters Abbreviated Journal Appl Phys Lett
Volume 104 Issue 17 Pages 173106
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Moire patterns in the pseudo-magnetic field and in the strain profile of graphene (GE) when put on top of a hexagonal lattice substrate are predicted from elasticity theory. The van der Waals interaction between GE and the substrate induces out-of-plane deformations in graphene which results in a strain field, and consequently in a pseudo-magnetic field. When the misorientation angle is about 0.5 degrees, a three-fold symmetric strain field is realized that results in a pseudo-magnetic field very similar to the one proposed by F. Guinea, M. I. Katsnelson, and A. K. Geim [Nature Phys. 6, 30 (2010)]. Our results show that the periodicity and length of the pseudo-magnetic field can be tuned in GE by changing the misorientation angle and substrate adhesion parameters and a considerable energy gap (23 meV) can be obtained due to out-of-plane deformation of graphene which is in the range of recent experimental measurements (20-30 meV). (C) 2014 AIP Publishing LLC.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000336142500066 Publication Date 2014-05-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0003-6951;1077-3118; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.411 Times cited 14 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem Foundation of the Flemish Government. M.N.-A. was supported by the EU-Marie Curie IIF postdoc Fellowship 299855. ; Approved Most recent IF: 3.411; 2014 IF: 3.302
Call Number UA @ lucian @ c:irua:117724 Serial 1375
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Author Schoelz, J.K.; Xu, P.; Meunier, V.; Kumar, P.; Neek-Amal, M.; Thibado, P.M.; Peeters, F.M.
Title (up) Graphene ripples as a realization of a two-dimensional Ising model : a scanning tunneling microscope study Type A1 Journal article
Year 2015 Publication Physical review: B: condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 91 Issue 91 Pages 045413
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Ripples in pristine freestanding graphene naturally orient themselves in an array that is alternately curved-up and curved-down; maintaining an average height of zero. Using scanning tunneling microscopy (STM) to apply a local force, the graphene sheet will reversibly rise and fall in height until the height reaches 60%-70% of its maximum at which point a sudden, permanent jump occurs. We successfully model the ripples as a spin-half Ising magnetic system, where the height of the graphene plays the role of the spin. The permanent jump in height, controlled by the tunneling current, is found to be equivalent to an antiferromagnetic-to-ferromagnetic phase transition. The thermal load underneath the STM tip alters the local tension and is identified as the responsible mechanism for the phase transition. Four universal critical exponents are measured from our STM data, and the model provides insight into the statistical role of graphene's unusual negative thermal expansion coefficient.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000348762200011 Publication Date 2015-01-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 21 Open Access
Notes ; This work was supported in part by Office of Naval Research (USA) under Grant No. N00014-10-1-0181 and National Science Foundation (USA) under Grant No. DMR-0855358. F. M. Peeters and M. Neek-Amal were supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem Foundation of the Flemish Government. ; Approved Most recent IF: 3.836; 2015 IF: 3.736
Call Number c:irua:123866 Serial 1377
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Author Jalali, H.; Khoeini, F.; Peeters, F.M.; Neek-Amal, M.
Title (up) Hydration effects and negative dielectric constant of nano-confined water between cation intercalated MXenes Type A1 Journal article
Year 2021 Publication Nanoscale Abbreviated Journal Nanoscale
Volume 13 Issue 2 Pages 922-929
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract Using electrochemical methods a profound enhancement of the capacitance of electric double layer capacitor electrodes was reported when water molecules are strongly confined into the two-dimensional slits of titanium carbide MXene nanosheets [A. Sugahara et al., Nat. Commun., 2019, 10, 850]. We study the effects of hydration on the dielectric properties of nanoconfined water and supercapacitance properties of the cation intercalated MXene. A model for the electric double layer capacitor is constructed where water molecules are strongly confined in two-dimensional slits of MXene. We report an abnormal dielectric constant and polarization of nano-confined water between MXene layers. We found that by decreasing the ionic radius of the intercalated cations and in a critical hydration shell radius the capacitance of the system increases significantly (similar or equal to 200 F g(-1)) which can be interpreted as a negative permittivity. This study builds a bridge between the fundamental understanding of the dielectric properties of nanoconfined water and the capability of using MXene films for supercapacitor technology, and in doing so provides a solid theoretical support for recent experiments.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000610368100035 Publication Date 2020-12-08
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2040-3364 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 7.367 Times cited 3 Open Access Not_Open_Access
Notes ; ; Approved Most recent IF: 7.367
Call Number UA @ admin @ c:irua:176141 Serial 6690
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Author Faraji, F.; Neek-Amal, M.; Neyts, E.C.; Peeters, F.M.
Title (up) Indentation of graphene nano-bubbles Type A1 Journal article
Year 2022 Publication Nanoscale Abbreviated Journal Nanoscale
Volume 14 Issue 15 Pages 5876-5883
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Molecular dynamics simulations are used to investigate the effect of an AFM tip when indenting graphene nano bubbles filled by a noble gas (i.e. He, Ne and Ar) up to the breaking point. The failure points resemble those of viral shells as described by the Foppl-von Karman (FvK) dimensionless number defined in the context of elasticity theory of thin shells. At room temperature, He gas inside the bubbles is found to be in the liquid state while Ne and Ar atoms are in the solid state although the pressure inside the nano bubble is below the melting pressure of the bulk. The trapped gases are under higher hydrostatic pressure at low temperatures than at room temperature.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000776763000001 Publication Date 2022-03-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2040-3364; 2040-3372 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.7 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 6.7
Call Number UA @ admin @ c:irua:187924 Serial 7171
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Author Beheshtian, J.; Sadeghi, A.; Neek-Amal, M.; Michel, K.H.; Peeters, F.M.
Title (up) Induced polarization and electronic properties of carbon-doped boron nitride nanoribbons Type A1 Journal article
Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 86 Issue 19 Pages 195433-195438
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The electronic properties of boron nitride nanoribbons (BNNRs) doped with a line of carbon atoms are investigated using density functional calculations. By replacing a line of alternating B and N atoms with carbons, three different configurations are possible depending on the type of the atoms which bond to the carbons. We found very different electronic properties for these configurations: (i) the NCB arrangement is strongly polarized with a large dipole moment having an unexpected direction, (ii) the BCB and NCN arrangements are nonpolar with zero dipole moment, (iii) the doping by a carbon line reduces the band gap regardless of the local arrangement of the borons and the nitrogens around the carbon line, and (iv) the polarization and energy gap of the carbon-doped BNNRs can be tuned by an electric field applied parallel to the carbon line. Similar effects were found when either an armchair or zigzag line of carbon was introduced.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000311694200006 Publication Date 2012-11-29
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 41 Open Access
Notes ; We would like to thank J. M. Pereira and S. Goedecker for helpful discussions. This work was supported by the Flemish Science Foundation (FWO-Vl), the ESF-EuroGRAPHENE project CONGRAN. M. N.-A is supported by EU-Marie Curie IIF postdoc Fellowship/299522. ; Approved Most recent IF: 3.836; 2012 IF: 3.767
Call Number UA @ lucian @ c:irua:105136 Serial 1603
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Author de Aquino, B.R.H.; Ghorbanfekr-Kalashami, H.; Neek-Amal, M.; Peeters, F.M.
Title (up) Ionized water confined in graphene nanochannels Type A1 Journal article
Year 2019 Publication Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys
Volume 21 Issue 18 Pages 9285-9295
Keywords A1 Journal article; Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract When confined between graphene layers, water behaves differently from the bulk and exhibits unusual properties such as fast water flow and ordering into a crystal. The hydrogen-bonded network is affected by the limited space and by the characteristics of the confining walls. The presence of an extraordinary number of hydronium and hydroxide ions in narrow channels has the following effects: (i) they affect water permeation through the channel, (ii) they may interact with functional groups on the graphene oxide surface and on the edges, and (iii) they change the thermochemistry of water, which are fundamentally important to understand, especially when confined water is subjected to an external electric field. Here we study the physical properties of water when confined between two graphene sheets and containing hydronium and hydroxide. We found that: (i) there is a disruption in the solvation structure of the ions, which is also affected by the layered structure of confined water, (ii) hydronium and hydroxide occupy specific regions inside the nanochannel, with a prevalence of hydronium (hydroxide) ions at the edges (interior), and (iii) ions recombine more slowly in confined systems than in bulk water, with the recombination process depending on the channel height and commensurability between the size of the molecules and the nanochannel height – a decay of 20% (40%) in the number of ions in 8 ps is observed for a channel height of h = 7 angstrom (bulk water). Our work reveals distinctive properties of water confined in a nanocapillary in the presence of additional hydronium and hydroxide ions.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000472922500028 Publication Date 2019-03-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1463-9076; 1463-9084 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.123 Times cited 9 Open Access
Notes ; This work was supported by the Fund for Scientific Research Flanders (FWO-Vl) and the Methusalem programe. ; Approved Most recent IF: 4.123
Call Number UA @ admin @ c:irua:161377 Serial 5419
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