“Speciation of aerosols by combining bulk ion chromatography and thin-window electron probe micro analysis”. Eyckmans K, de Hoog J, van der Auwera L, Van Grieken R, International journal of environmental analytical chemistry 83, 777 (2003). http://doi.org/10.1080/0306731031000118934
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1080/0306731031000118934
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“Leaching of nutrients and trace metals from aerosol samples: a comparison between a re-circulation and an ultrasound system”. Eyckmans K, Zhang J, de Hoog J, Joos P, Van Grieken R, International journal of environmental analytical chemistry 80, 227 (2001). http://doi.org/10.1080/03067310108044372
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1080/03067310108044372
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“Elemental composition of bottom-sediments from Pangani river basin, Tanzania : lithogenic and anthropogenic sources”. Hellar-Kihampa H, Potgieter-Vermaak S, van Meel K, Gatto Rotondo G, Kishimba M, Van Grieken R, Toxicological and environmental chemistry 94, 525 (2012). http://doi.org/10.1080/02772248.2011.648940
Abstract: River-bed sediments from the Pangani basin, Tanzania, were characterized for elemental compositions, following contamination risks from rapid expansions of human activities in the area. Samples were collected during two individual seasons and analyzed by high-polarizing beam energy dispersive X-ray fluorescence (EDXRF) for eight major and 14 trace elements. Evaluation of enrichment factors (EFs) was used to investigate the elemental flux and assess the contributions of natural and anthropogenic influences. The abundances of the major elements followed the order Si > Al > Fe > Ca > K > Ti > Mn > P, similar to that of the upper earth's crust, and were generally from the weathering of the bed-rock. The high concentrations of typical anthropogenic trace-elements (Cr < 160 mg kg−1, V < 85 mg kg−1, Ni < 60 mg kg−1, Cu < 87 mg kg−1, La < 90 mg kg−1) coupled with high EFs (>2) in some locations indicated contamination associated with agricultural and industrial activities. Factor analysis extracted five principal components that contributed to 96.0% of the total observed variance. The results indicated that river-bed sediments of the Pangani basin were influenced to a larger extent by lithogenic sources than anthropogenic impacts.
Keywords: A1 Journal article; Pharmacology. Therapy; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1080/02772248.2011.648940
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“Assessing the acidification risk in the Lake Baikal region”. Semenov MY, Khodzher TV, Obolkin VA, Domysheva VM, Golobokova LP, Kobeleva NA, Netsvetaeva OG, Potemkin VL, Van Grieken R, Fukuzaki N, Chemistry and ecology 22, 1 (2006). http://doi.org/10.1080/02757540500456955
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1080/02757540500456955
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“Supercooled molecular liquids and the glassy phases of chemically bonded N, P, As, Si and Ge”. Matthai CC, March NH, Lamoen D, Physics and chemistry of liquids 47, 607 (2009). http://doi.org/10.1080/00319100903148553
Abstract: Glassy phases which have insulating character exist for a variety of monatomic species. By contrast, until recently, it has been possible to make bulk metallic glasses (BMG) by vitrification only for multicomponent systems. After a relatively brief summary on supercooling of a few molecular liquids, we review some of the recently reported results on molecular assemblies of the series N, P, As and amorphous Si and Ge. Based on these results, we suggest that the transition metals with their directional bonding might be suitable candidates for the production of BMG by vitrification.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 1.145
Times cited: 1
DOI: 10.1080/00319100903148553
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“Relativistic virial relations for both homogeneous and spatially varying electron liquids”. Leys FE, March NH, Lamoen D, Physics And Chemistry Of Liquids 42, 423 (2004). http://doi.org/10.1080/00319100410001697873
Keywords: A1 Journal article; Electron Microscopy for Materials Science (EMAT);
Impact Factor: 1.145
DOI: 10.1080/00319100410001697873
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“Some properties of a model liquid of C60 buckyballs”. Alonso JA, López MJ, March NH, Lamoen D, Physics And Chemistry Of Liquids 40, 457 (2002). http://doi.org/10.1080/00319100290010809
Keywords: A1 Journal article; Electron Microscopy for Materials Science (EMAT);
Impact Factor: 1.145
Times cited: 4
DOI: 10.1080/00319100290010809
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“Gradient expansion and beyond for stress tensor and tangential pressure deficit through a planar liquid-vapour interface”. Lamoen D, March NH, Physics And Chemistry Of Liquids 38, 495 (2000). http://doi.org/10.1080/00319100008030296
Keywords: A1 Journal article; Electron Microscopy for Materials Science (EMAT);
Impact Factor: 1.145
Times cited: 1
DOI: 10.1080/00319100008030296
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“Stable single-layers of calcium halides (CaX₂, X = F, Cl, Br, I)”. Baskurt M, Yagmurcukardes M, Peeters FM, Sahin H, Journal Of Chemical Physics 152, 164116 (2020). http://doi.org/10.1063/5.0006011
Abstract: By means of density functional theory based first-principles calculations, the structural, vibrational, and electronic properties of 1H- and 1T-phases of single-layer CaX2 (X = F, Cl, Br, or I) structures are investigated. Our results reveal that both the 1H- and 1T-phases are dynamically stable in terms of their phonon band dispersions with the latter being the energetically favorable phase for all single-layers. In both phases of single-layer CaX2 structures, significant phonon softening occurs as the atomic radius increases. In addition, each structural phase exhibits distinctive Raman active modes that enable one to characterize either the phase or the structure via Raman spectroscopy. The electronic band dispersions of single-layer CaX2 structures reveal that all structures are indirect bandgap insulators with a decrease in bandgaps from fluorite to iodide crystals. Furthermore, the calculated linear elastic constants, in-plane stiffness, and Poisson ratio indicate the ultra-soft nature of CaX2 single-layers, which is quite important for their nanoelastic applications. Overall, our study reveals that with their dynamically stable 1T- and 1H-phases, single-layers of CaX2 crystals can be alternative ultra-thin insulators.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 4.4
Times cited: 14
DOI: 10.1063/5.0006011
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“Monitoring the effect of asymmetrical vertical strain on Janus single layers of MoSSe via spectrum”. Kandemir A, Peeters FM, Sahin H, The journal of chemical physics 149, 084707 (2018). http://doi.org/10.1063/1.5043207
Abstract: Using first principles calculations, we study the structural and phononic properties of the recently synthesized Janus type single layers of molybdenum dichalcogenides. The Janus MoSSe single layer possesses 2H crystal structure with two different chalcogenide sides that lead to out-of-plane anisotropy. By virtue of the asymmetric structure of the ultra-thin Janus type crystal, we induced the out-of-plane anisotropy to show the distinctive vertical pressure effect on the vibrational properties of the Janus material. It is proposed that for the corresponding Raman active optical mode of the Janus structure, the phase modulation and the magnitude ratio of the strained atom and its first neighbor atom adjust the distinctive change in the eigen-frequencies and Raman activity. Moreover, a strong variation in the Raman activity of the Janus structure is obtained under bivertical and univertical strains. Not only eigen-frequency shifts but also Raman activities of the optical modes of the Janus structure exhibit distinguishable features. This study reveals that the vertical anisotropic feature of the Janus structure under Raman measurement allows us to distinguish which side of the Janus crystal interacts with the externals (substrate, functional adlayers, or dopants). Published by AIP Publishing.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.965
Times cited: 11
DOI: 10.1063/1.5043207
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“Structural transitions and long-time self-diffusion of interacting colloids confined by a parabolic potential”. Euan-Diaz E, Herrera-Velarde S, Misko VR, Peeters FM, Castaneda-Priego R, The journal of chemical physics 142, 024902 (2015). http://doi.org/10.1063/1.4905215
Abstract: We report on the ordering and dynamics of interacting colloidal particles confined by a parabolic potential. By means of Brownian dynamics simulations, we find that by varying the magnitude of the trap stiffness, it is possible to control the dimension of the system and, thus, explore both the structural transitions and the long-time self-diffusion coefficient as a function of the degree of confinement. We particularly study the structural ordering in the directions perpendicular and parallel to the confinement. Further analysis of the local distribution of the first-neighbors layer allows us to identify the different structural phases induced by the parabolic potential. These results are summarized in a structural state diagram that describes the way in which the colloidal suspension undergoes a structural re-ordering while increasing the confinement. To fully understand the particle dynamics, we take into account hydrodynamic interactions between colloids; the parabolic potential constricts the available space for the colloids, but it does not act on the solvent. Our findings show a non-linear behavior of the long-time self-diffusion coefficient that is associated to the structural transitions induced by the external field. (C) 2015 AIP Publishing LLC.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.965
Times cited: 7
DOI: 10.1063/1.4905215
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“Electronic properties of graphene nano-flakes : energy gap, permanent dipole, termination effect, and Raman spectroscopy”. Singh SK, Neek-Amal M, Peeters FM, The journal of chemical physics 140, 074304 (2014). http://doi.org/10.1063/1.4865414
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.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.965
Times cited: 30
DOI: 10.1063/1.4865414
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“Charge transfer and polymer phases in AC60 (A=K, Rb, Cs) fullerides”. Nikolaev AV, Prassides K, Michel KH, The journal of chemical physics 108, 4912 (1998). http://doi.org/10.1063/1.475900
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.965
Times cited: 14
DOI: 10.1063/1.475900
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“Adsorption of potassium and oxygen on graphite: a theoretical study”. Lamoen D, Persson BNJ, Journal Of Chemical Physics 108, 3332 (1998). http://doi.org/10.1063/1.475732
Keywords: A1 Journal article; Electron Microscopy for Materials Science (EMAT);
Impact Factor: 2.965
Times cited: 91
DOI: 10.1063/1.475732
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“Crystal field, orientational order, and lattice contraction in solid C60”. Lamoen D, Michel KH, The journal of chemical physics 101, 1435 (1994). http://doi.org/10.1063/1.467768
Abstract: A model of the intermolecular potential in solid C-60, which is based on Born-Mayer repulsions, van der Waals attractions, and electrostatic multipoles, is presented. The potential is expanded in terms of multipolar rotator functions. The orientation-orientation interaction and the crystal field are calculated. The orientational phase transition to the Pa3 phase is studied with the methods of statistical mechanics. The discontinuity of the order parameter at the transition and the temperature evolution of the order parameter are calculated. The lattice contraction at the phase transition is evaluated. The influence of the lattice contraction on the crystal field and on the orientational order is studied.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.952
Times cited: 39
DOI: 10.1063/1.467768
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“Molecular structure and orientational ordering in solid C60”. Michel KH, The journal of chemical physics 97, 5155 (1992). http://doi.org/10.1063/1.463813
Abstract: A microscopic theory, which describes the orientational dynamics of C60 molecules in the face-centered cubic phase of C60-fullerite, is formulated or the case of a complex molecular structure. Interaction centers which comprise atoms, double bonds, and single bonds as molecular constituents contribute to the intermolecular potential. Orientation dependent physical properties are described in terms of symmetry-adapted rotator functions. It is found that a same set of rotator functions is sufficient even in the case of a complex molecular structure. Phase transition temperatures are discussed for various models of molecular structure.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.952
Times cited: 20
DOI: 10.1063/1.463813
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“Orientational ordering in solid C60 fullerene-cubane”. Verberck B, Vliegenthart GA, Gompper G, The journal of chemical physics 130, 154510 (2009). http://doi.org/10.1063/1.3098550
Abstract: We study the structure and phase behavior of fullerene-cubane C60·C8H8 by Monte Carlo simulation. Using a simple potential model capturing the icosahedral and cubic symmetries of its molecular constituents, we reproduce the experimentally observed phase transition from a cubic to an orthorhombic crystal lattice and the accompanying rotational freezing of the C60 molecules. We elaborate a scheme to identify the low-temperature orientations of individual molecules and to detect a pattern of orientational ordering similar to the arrangement of C60 molecules in solid C60. Our configuration of orientations supports a doubled periodicity along one of the crystal axes.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.965
Times cited: 8
DOI: 10.1063/1.3098550
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“Superposition of quantum and classical rotational motions in Sc2C2@C84 fullerite”. Michel KH, Verberck B, Hulman M, Kuzmany H, Krause M, The journal of chemical physics 126, 064304 (2007). http://doi.org/10.1063/1.2434175
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.965
Times cited: 14
DOI: 10.1063/1.2434175
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“Valence electronic charge density of distorted C60-monomers in polymerized KC60 and RbC60”. Verberck B, Popov VN, Nikolaev AV, Lamoen D, The journal of chemical physics 121, 321 (2004). http://doi.org/10.1063/1.1755676
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.965
Times cited: 7
DOI: 10.1063/1.1755676
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“Thermodynamic consistency and integral equations for the liquid structure”. Leys FE, March NH, Lamoen D, Journal Of Chemical Physics 117, 10726 (2002). http://doi.org/10.1063/1.1522377
Keywords: A1 Journal article; Electron Microscopy for Materials Science (EMAT);
Impact Factor: 2.965
DOI: 10.1063/1.1522377
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“Single chain elasticity and thermoelasticity of polyethylene”. Titantah JT, Pierleoni C, Ryckaert J-P, The journal of chemical physics 117, 9028 (2002). http://doi.org/10.1063/1.1514974
Abstract: Single-chain elasticity of polyethylene at theta point up to 90% of stretching with respect to its contour length is computed by Monte Carlo simulation of an atomistic model in continuous space. The elasticity law together with the free-energy and the internal energy variations with stretching are found to be very well represented by the wormlike chain model up to 65% of the chain elongation, provided the persistence length is treated as a temperature-dependent parameter. Beyond this value of elongation simple ideal chain models are not able to describe the Monte Carlo data in a thermodynamic consistent way. This study reinforces the use of the wormlike chain model to interpret experimental data on the elasticity of synthetic polymers in the finite extensibility regime, provided the chain is not yet in its fully stretched regime. Specific solvent effects on the elasticity law and the partition between energetic and entropic contributions to single chain elasticity are investigated. (C) 2002 American Institute of Physics.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 2.965
Times cited: 5
DOI: 10.1063/1.1514974
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“Crystal structures of polymerized fullerides AC60, A=K, Rb, Cs, and alkali-mediated interactions”. Verberck B, Michel KH, Nikolaev AV, The journal of chemical physics 116, 10462 (2002). http://doi.org/10.1063/1.1475745
Abstract: Starting from a model of rigid interacting C-60 polymer chains on an orthorhombic lattice, we study the mutual orientation of the chains and the stability of the crystalline structures Pmnn and I2/m. We take into account (i) van der Waals interactions and electric quadrupole interactions between C-60 monomers on different chains as well as (ii) interactions of the monomers with the surrounding alkali atoms. The direct interactions (i) always lead to an antiferrorotational structure Pmnn with alternate orientation of the C-60 chains in planes (001). The interactions (ii) with the alkalis consist of two parts: translation-rotation (TR) coupling where the orientations of the chains interact with displacements of the alkalis, and quadrupolar electronic polarizability (ep) coupling, where the electric quadrupoles on the C-60 monomers interact with induced quadrupoles due to excited electronic d-states of the alkalis. Both interactions (ii) lead to an effective orientation-orientation interaction between the C-60 chains and always favor the ferrorotational structure I2/m, where C-60 chains have a same orientation. The structures Pmnn for KC60 and I2/m for Rb- and CsC60 are the result of a competition between the direct interaction (i) and the alkali-mediated interactions (ii). In Rb- and CsC60 the latter are found to be dominant, the preponderant role being played by the quadrupolar electronic polarizability of the alkali ions. (C) 2002 American Institute of Physics.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.965
Times cited: 12
DOI: 10.1063/1.1475745
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“From Bi4V2O11 to Bi4V2O10.66: the VV-VIV transformation in the Aurovillius-type framework”. Huvé, M, Vannier R-N, Nowogrocki G, Mairesse G, Van Tendeloo G, Journal of materials chemistry 6, 1339 (1996). http://doi.org/10.1039/jm9960601339
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Times cited: 63
DOI: 10.1039/jm9960601339
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“Plasma-catalytic one-step steam reforming of CH₄, to CH₃OH and H₂, promoted by oligomerized [Cu-O-Cu] species on zeolites”. Fang W, Wang X, Li S, Hao Y, Yang Y, Zhao W, Liu R, Li D, Li C, Gao X, Wang L, Guo H, Yi Y, Green chemistry : cutting-edge research for a greener sustainable future 26, 5150 (2024). http://doi.org/10.1039/D4GC00265B
Abstract: Oligomerized [Cu-O-Cu] species are reported to be efficient in promoting plasma catalytic one-step steam reforming of methane to methanol and hydrogen, achieving 6.8% CH4 conversion and 73.1% CH3OH selectivity without CO2.
Keywords: A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 9.8
DOI: 10.1039/D4GC00265B
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“High thermoelectric figure of merit in p-type Mg₃Si₂Te₆: role of multi-valley bands and high anharmonicity”. Pandey T, Peeters FM, Milošević, MV, Journal of materials chemistry C : materials for optical and electronic devices 11, 11185 (2023). http://doi.org/10.1039/D3TC02169F
Abstract: Silicon-based materials are attractive for thermoelectric applications due to their thermal stability, chemical inertness, and natural abundance of silicon. Here, using a combination of first-principles and Boltzmann transport calculations we report the thermoelectric properties of the recently synthesized compound Mg3Si2Te6. Our analysis reveals that Mg3Si2Te6 is a direct bandgap semiconductor with a bandgap of 1.6 eV. The combination of heavy and light valence bands, along with a high valley degeneracy, results in a large power factor under p-type doping. We also find that Mg is weakly bonded both within and between the layers, leading to low phonon group velocities. The vibrations of the Mg atoms are localized and make a significant contribution to phonon-phonon scattering. This high anharmonicity, coupled with low phonon group velocity, results in a low lattice thermal conductivity of & kappa;(l) = 0.5 W m(-1) K-1 at room temperature, along the cross-plane direction. Combining excellent electronic transport properties and low & kappa;(l), p-type Mg3Si2Te6 achieves figure-of-merit (zT) values greater than 1 at temperatures above 600 K. Specifically, a zT of 2.0 is found at 900 K along the cross-plane direction. Our findings highlight the importance of structural complexity and chemical bonding in electronic and phonon transport, providing guiding insights for further design of Si-based thermoelectrics.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 6.4
Times cited: 1
DOI: 10.1039/D3TC02169F
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“Interface thermal conductivities induced by van der Waals interactions”. Dong HM, Liang HP, Tao ZH, Duan YF, Milošević, MV, Chang K, Physical chemistry, chemical physics 26, 4047 (2024). http://doi.org/10.1039/D3CP05377F
Abstract: The interface heat transfer of two layers induced by van der Waals (vdW) contacts is theoretically investigated, based on first-principles calculations at low temperatures. The results suggest that out-of-plane acoustic phonons with low frequencies dominate the interface thermal transport due to the vdW interaction. The interface thermal conductivity is proportional to the cubic of temperature at very low temperatures, but becomes linearly proportional to temperature as temperature increases. We show that manipulating the strain alters vdW coupling, leading to increased interfacial thermal conductivity at the interface. Our findings provide valuable insights into the interface heat transport in vdW heterostructures and support further design and optimization of electronic and optoelectronic nanodevices based on vdW contacts. The heat transfer induced by van der Waals contacts is dominated by ZA phonons. The interface thermal conductivity is proportional to the cubic of temperature, but becomes linearly proportional to temperature as temperature increases.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.3
DOI: 10.1039/D3CP05377F
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“Reduction-enhanced water flux through layered graphene oxide (GO) membranes stabilized with H3O+ and OH- ions”. Gogoi A, Neyts EC, Peeters FM, Physical chemistry, chemical physics 26, 10265 (2024). http://doi.org/10.1039/D3CP04097F
Abstract: Graphene oxide (GO) is one of the most promising candidates for next generation of atomically thin membranes. Nevertheless, one of the major issues for real world application of GO membranes is their undesirable swelling in an aqueous environment. Recently, we demonstrated that generation of H3O+ and OH- ions (e.g., with an external electric field) in the interlayer gallery could impart aqueous stability to the layered GO membranes (A. Gogoi, ACS Appl. Mater. Interfaces, 2022, 14, 34946). This, however, compromises the water flux through the membrane. In this study, we report on reducing the GO nanosheets as a solution to this issue. With the reduction of the GO nanosheets, the water flux through the layered GO membrane initially increases and then decreases again beyond a certain degree of reduction. Here, two key factors are at play. Firstly, the instability of the H-bond network between water molecules and the GO nanosheets, which increases the water flux. Secondly, the pore size reduction in the interlayer gallery of the membranes, which decreases the water flux. We also observe a significant improvement in the salt rejection of the membranes, due to the dissociation of water molecules in the interlayer gallery. In particular, for the case of 10% water dissociation, the water flux through the membranes can be enhanced without altering its selectivity. This is an encouraging observation as it breaks the traditional tradeoff between water flux and salt rejection of a membrane.
Keywords: A1 Journal article; Condensed Matter Theory (CMT); Modelling and Simulation in Chemistry (MOSAIC)
Impact Factor: 3.3
DOI: 10.1039/D3CP04097F
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“Experimental and theoretical investigation of synthesis and properties of dodecanethiol-functionalized MoS₂”. Duran TA, Šabani D, Milošević, MV, Sahin H, Physical chemistry, chemical physics 25, 27141 (2023). http://doi.org/10.1039/D3CP02631K
Abstract: Herein, we investigate the DDT (1-dodecanethiol) functionalization of exfoliated MoS2 by using experimental and theoretical tools. For the functionalization of MoS2, DDT treatment was incorporated into the conventional NMP (N-methyl pyrrolidone) exfoliation procedure. Afterward, it has been demonstrated that the functionalization process is successful through optical, morphological and theoretical analysis. The D, G and 2LA peaks seen in the Raman spectrum of exfoliated NMP-MoS2 particles, indicate the formation of graphitic species on MoS2 sheets. In addition, as the DDT ratio increases, the vacant sites on MoS2 sheets diminish. Moreover, at an optimized ratio of DDT-NMP, the maximum number of graphitic quantum dots (GQDs) is observed on MoS2 nanosheets. Specifically, the STEM and AFM data confirm that GQDs reside on the MoS2 nano-sheets and also that the particle size of the DDT-MoS2 is mostly fixed, while the NMP-MoS2 show many smaller and distributed sizes. The comparison of PL intensities of the NMP-MoS2 and DDT-MoS2 samples states a 10-fold increment is visible, and a 60-fold increment in NIR region photoluminescent properties. Moreover, our results lay out understanding and perceptions on the surface and edge chemistry of exfoliated MoS2 and open up more opportunities for MoS2 and GQD particles with broader applications.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.3
DOI: 10.1039/D3CP02631K
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“High-throughput analysis of tetragonal transition metal Xenes”. Yorulmaz U, Šabani D, Yagmurcukardes M, Sevik C, Milošević, MV, Physical chemistry, chemical physics 24, 29406 (2022). http://doi.org/10.1039/D2CP04191J
Abstract: We report a high-throughput first-principles characterization of the structural, mechanical, electronic, and vibrational properties of tetragonal single-layer transition metal Xenes (t-TMXs). Our calculations revealed 22 dynamically, mechanically and chemically stable structures among the 96 possible free-standing layers present in the t-TMX family. As a fingerprint for their structural identification, we identified four characteristic Raman active phonon modes, namely three in-plane and one out-of-plane optical branches, with various intensities and frequencies depending on the material in question. Spin-polarized electronic calculations demonstrated that anti-ferromagnetic (AFM) metals, ferromagnetic (FM) metals, AFM semiconductors, and non-magnetic semiconductor materials exist within this family, evidencing the potential of t-TMXs for further use in multifunctional heterostructures.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.3
Times cited: 1
DOI: 10.1039/D2CP04191J
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“Stability of adsorption of Mg and Na on sulfur-functionalized MXenes”. Chaney G, Cakir D, Peeters FM, Ataca C, Physical Chemistry Chemical Physics 23, 25424 (2021). http://doi.org/10.1039/D1CP03433B
Abstract: Two-dimensional materials composed of transition metal carbides and nitrides (MXenes) are poised to revolutionize energy conversion and storage. In this work, we used density functional theory (DFT) to investigate the adsorption of Mg and Na adatoms on five M2CS2 monolayers (where M = Mo, Nb, Ti, V, and Zr) for battery applications. We assessed the stability of the adatom (i.e. Na and Mg)-monolayer systems by calculating adsorption and formation energies, as well as voltages as a function of surface coverage. For instance, we found that Mo2CS2 cannot support a full layer of Na nor even a single Mg atom. Na and Mg exhibit the strongest binding on Zr2CS2, followed by Ti2CS2, Nb2CS2 and V2CS2. Using the nudged elastic band method (NEB), we computed promising diffusion barriers for both dilute and nearly full ion surface coverage cases. In the dilute ion adsorption case, a single Mg and Na atom on Ti2CS2 experience similar to 0.47 eV and similar to 0.10 eV diffusion barriers between the lowest energy sites, respectively. For a nearly full surface coverage, a Na ion moving on Ti2CS2 experiences a similar to 0.33 eV energy barrier, implying a concentration-dependent diffusion barrier. Our molecular dynamics results indicate that the three (one) layers (layer) of the Mg (Na) ion on both surfaces of Ti2CS2 remain stable at T = 300 K. While, according to voltage calculations, Zr2CS2 can store Na up to three atomic layers, our MD simulations predict that the outermost layers detach from the Zr2CS2 monolayer due to the weak interaction between Na ions and the monolayer. This suggests that MD simulations are essential to confirm the stability of an ion-electrode system – an insight that is mostly absent in previous studies.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 4.123
Times cited: 7
DOI: 10.1039/D1CP03433B
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