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“Mo2C as a high capacity anode material: a first-principles study”. Çakir D, Sevik C, Gulseren O, Peeters FM, Journal of materials chemistry A : materials for energy and sustainability 4, 6029 (2016). http://doi.org/10.1039/C6TA01918H
Abstract: The adsorption and diffusion of Li, Na, K and Ca atoms on a Mo2C monolayer are systematically investigated by using first principles methods. We found that the considered metal atoms are strongly bound to the Mo2C monolayer. However, the adsorption energies of these alkali and earth alkali elements decrease as the coverage increases due to the enhanced repulsion between the metal ions. We predict a significant charge transfer from the ad-atoms to the Mo2C monolayer, which indicates clearly the cationic state of the metal atoms. The metallic character of both pristine and doped Mo2C ensures a good electronic conduction that is essential for an optimal anode material. Low migration energy barriers are predicted as small as 43 meV for Li, 19 meV for Na and 15 meV for K, which result in the very fast diffusion of these atoms on Mo2C. For Mo2C, we found a storage capacity larger than 400 mA h g(-1) by the inclusion of multilayer adsorption. Mo2C expands slightly upon deposition of Li and Na even at high concentrations, which ensures the good cyclic stability of the atomic layer. The calculated average voltage of 0.68 V for Li and 0.30 V for Na ions makes Mo2C attractive for low charging voltage applications.
Keywords: A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Impact Factor: 8.867
Times cited: 202
DOI: 10.1039/C6TA01918H
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“Two electron quantum disks”. Peeters FM, Schweigert VA, Physical review : B : condensed matter and materials physics 53, 1468 (1996). http://doi.org/10.1103/PhysRevB.53.1468
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.736
Times cited: 204
DOI: 10.1103/PhysRevB.53.1468
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“Extra Dirac points in the energy spectrum for superlattices on single-layer graphene”. Barbier M, Vasilopoulos P, Peeters FM, Physical review : B : condensed matter and materials physics 81, 075438 (2010). http://doi.org/10.1103/PhysRevB.81.075438
Abstract: We investigate the emergence of extra Dirac points in the electronic structure of a periodically spaced barrier system, i.e., a superlattice, on single-layer graphene, using a Dirac-type Hamiltonian. Using square barriers allows us to find analytic expressions for the occurrence and location of these new Dirac points in k space and for the renormalization of the electron velocity near them in the low-energy range. In the general case of unequal barrier and well widths the new Dirac points move away from the Fermi level and for given heights of the potential barriers there is a minimum and maximum barrier width outside of which the new Dirac points disappear. The effect of these extra Dirac points on the density of states and on the conductivity is investigated.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 211
DOI: 10.1103/PhysRevB.81.075438
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“Confined states and direction-dependent transmission in graphene quantum wells”. Milton Pereira J, Mlinar V, Peeters FM, Vasilopoulos P, Physical review : B : condensed matter and materials physics 74, 045424 (2006). http://doi.org/10.1103/PhysRevB.74.045424
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 212
DOI: 10.1103/PhysRevB.74.045424
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“Direction-dependent tunneling through nanostructured magnetic barriers in graphene”. Masir MR, Vasilopoulos P, Matulis A, Peeters FM, Physical review : B : condensed matter and materials physics 77, 235443 (2008). http://doi.org/10.1103/PhysRevB.77.235443
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 212
DOI: 10.1103/PhysRevB.77.235443
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“High-capacity hydrogen storage in Al-adsorbed graphene”. Ao ZM, Peeters FM, Physical review : B : condensed matter and materials physics 81, 205406 (2010). http://doi.org/10.1103/PhysRevB.81.205406
Abstract: A high-capacity hydrogen storage mediumAl-adsorbed grapheneis proposed based on density-functional theory calculations. We find that a graphene layer with Al adsorbed on both sides can store hydrogen up to 13.79 wt % with average adsorption energy −0.193 eV/H2. Its hydrogen storage capacity is in excess of 6 wt %, surpassing U. S. Department of Energy (DOEs) target. Based on the binding-energy criterion and molecular-dynamics calculations, we find that hydrogen storage can be recycled at near ambient conditions. This high-capacity hydrogen storage is due to the adsorbed Al atoms that act as bridges to link the electron clouds of the H2 molecules and the graphene layer. As a consequence, a two-layer arrangement of H2 molecules is formed on each side of the Al-adsorbed graphene layer. The H2 concentration in the hydrogen storage medium can be measured by the change in the conductivity of the graphene layer.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 219
DOI: 10.1103/PhysRevB.81.205406
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“Tuning of the electronic and optical properties of single-layer black phosphorus by strain”. Çakir D, Sahin H, Peeters FM, Physical review : B : condensed matter and materials physics 90, 205421 (2014). http://doi.org/10.1103/PhysRevB.90.205421
Abstract: Using first principles calculations we showed that the electronic and optical properties of single-layer black phosphorus (BP) depend strongly on the applied strain. Due to the strong anisotropic atomic structure of BP, its electronic conductivity and optical response are sensitive to the magnitude and the orientation of the applied strain. We found that the inclusion of many body effects is essential for the correct description of the electronic properties of monolayer BP; for example, while the electronic gap of strainless BP is found to be 0.90 eV by using semilocal functionals, it becomes 2.31 eV when many-body effects are taken into account within the G(0)W(0) scheme. Applied tensile strain was shown to significantly enhance electron transport along zigzag direction of BP. Furthermore, biaxial strain is able to tune the optical band gap of monolayer BP from 0.38 eV (at -8% strain) to 2.07 eV (at 5.5%). The exciton binding energy is also sensitive to the magnitude of the applied strain. It is found to be 0.40 eV for compressive biaxial strain of -8%, and it becomes 0.83 eV for tensile strain of 4%. Our calculations demonstrate that the optical response of BP can be significantly tuned using strain engineering which appears as a promising way to design novel photovoltaic devices that capture a broad range of solar spectrum.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 219
DOI: 10.1103/PhysRevB.90.205421
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“Tuning of energy levels and optical properties of graphene quantum dots”. Zhang ZZ, Peeters FM, Physical review : B : condensed matter and materials physics 77, 235411 (2008). http://doi.org/10.1103/PhysRevB.77.235411
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 228
DOI: 10.1103/PhysRevB.77.235411
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“Hydrothermal synthesis and characterization of nanorods of various titanates and titanium dioxide”. Kolen'ko YV, Kovnir KA, Gavrilov AI, Garshev AV, Frantti J, Lebedev OI, Churagulov BR, Van Tendeloo G, Yoshimura M, The journal of physical chemistry : B : condensed matter, materials, surfaces, interfaces and biophysical 110, 4030 (2006). http://doi.org/10.1021/jp055687u
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.177
Times cited: 234
DOI: 10.1021/jp055687u
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“Spectral properties of classical two-dimensional clusters”. Schweigert VA, Peeters FM, Physical review : B : condensed matter and materials physics 51, 7700 (1995)
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.736
Times cited: 237
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“Atomic-scale determination of surface facets in gold nanorods”. Goris B, Bals S, van den Broek W, Carbó-Argibay E, Gómez-Graña S, Liz-Marzán LM, Van Tendeloo G, Nature materials 11, 930 (2012). http://doi.org/10.1038/NMAT3462
Abstract: It is widely accepted that the physical properties of nanostructures depend on the type of surface facets1, 2. For Au nanorods, the surface facets have a major influence on crucial effects such as reactivity and ligand adsorption and there has been controversy regarding facet indexing3, 4. Aberration-corrected electron microscopy is the ideal technique to study the atomic structure of nanomaterials5, 6. However, these images correspond to two-dimensional (2D) projections of 3D nano-objects, leading to an incomplete characterization. Recently, much progress was achieved in the field of atomic-resolution electron tomography, but it is still far from being a routinely used technique. Here we propose a methodology to measure the 3D atomic structure of free-standing nanoparticles, which we apply to characterize the surface facets of Au nanorods. This methodology is applicable to a broad range of nanocrystals, leading to unique insights concerning the connection between the structure and properties of nanostructures.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 39.737
Times cited: 261
DOI: 10.1038/NMAT3462
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“Controlled lateral anisotropy in correlated manganite heterostructures by interface-engineered oxygen octahedral coupling”. Liao Z, Huijben M, Zhong Z, Gauquelin N, Macke S, Green RJ, Van Aert S, Verbeeck J, Van Tendeloo G, Held K, Sawatzky GA, Koster G, Rijnders G, Nature materials 15, 425 (2016). http://doi.org/10.1038/nmat4579
Abstract: Controlled in-plane rotation of the magnetic easy axis in manganite heterostructures by tailoring the interface oxygen network could allow the development of correlated oxide-based magnetic tunnelling junctions with non-collinear magnetization, with possible practical applications as miniaturized high-switching-speed magnetic random access memory (MRAM) devices. Here, we demonstrate how to manipulate magnetic and electronic anisotropic properties in manganite heterostructures by engineering the oxygen network on the unit-cell level. The strong oxygen octahedral coupling is found to transfer the octahedral rotation, present in the NdGaO3 (NGO) substrate, to the La2/3Sr1/3MnO3 (LSMO) film in the interface region. This causes an unexpected realignment of the magnetic easy axis along the short axis of the LSMO unit cell as well as the presence of a giant anisotropic transport in these ultrathin LSMO films. As a result we possess control of the lateral magnetic and electronic anisotropies by atomic-scale design of the oxygen octahedral rotation.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 39.737
Times cited: 273
DOI: 10.1038/nmat4579
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“Adsorption of alkali, alkaline-earth, and 3d transition metal atoms on silicene”. Sahin H, Peeters FM, Physical review : B : condensed matter and materials physics 87, 085423 (2013). http://doi.org/10.1103/PhysRevB.87.085423
Abstract: The adsorption characteristics of alkali, alkaline-earth, and transition metal adatoms on silicene, a graphene-like monolayer structure of silicon are analyzed by means of first-principles calculations. In contrast to graphene, interaction between the metal atoms and the silicene surface is quite strong due to its highly reactive buckled hexagonal structure. In addition to structural properties, we also calculate the electronic band dispersion, net magnetic moment, charge transfer, work function, and dipole moment of the metal adsorbed silicene sheets. Alkali metals, Li, Na, and K, adsorb to hollow sites without any lattice distortion. As a consequence of the significant charge transfer from alkalis to silicene, metalization of silicene takes place. Trends directly related to atomic size, adsorption height, work function, and dipole moment of the silicene/alkali adatom system are also revealed. We found that the adsorption of alkaline-earth metals on silicene is entirely different from their adsorption on graphene. The adsorption of Be, Mg, and Ca turns silicene into a narrow gap semiconductor. Adsorption characteristics of eight transition metals Ti, V, Cr, Mn, Fe, Co, Mo, and W are also investigated. As a result of their partially occupied d orbital, transition metals show diverse structural, electronic, and magnetic properties. Upon the adsorption of transition metals, depending on the adatom type and atomic radius, the system can exhibit metal, half-metal, and semiconducting behavior. For all metal adsorbates, the direction of the charge transfer is from adsorbate to silicene, because of its high surface reactivity. Our results indicate that the reactive crystal structure of silicene provides a rich playground for functionalization at nanoscale. DOI: 10.1103/PhysRevB.87.085423
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 281
DOI: 10.1103/PhysRevB.87.085423
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“Electronically coupled complementary interfaces between perovskite band insulators”. Huijben M, Rijnders G, Blank DHA, Bals S, Van Aert S, Verbeeck J, Van Tendeloo G, Brinkman A, Hilgenkamp H, Nature materials 5, 556 (2006). http://doi.org/10.1038/nmat1675
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 39.737
Times cited: 315
DOI: 10.1038/nmat1675
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“Anomalous Raman spectra and thickness-dependent electronic properties of WSe2”. Sahin H, Tongay S, Horzum S, Fan W, Zhou J, Li J, Wu J, Peeters FM, Physical review : B : condensed matter and materials physics 87, 165409 (2013). http://doi.org/10.1103/PhysRevB.87.165409
Abstract: Typical Raman spectra of transition-metal dichalcogenides (TMDs) display two prominent peaks, E-2g and A(1g), that are well separated from each other. We find that these modes are degenerate in bulk WSe2 yielding one single Raman peak in contrast to other TMDs. As the dimensionality is lowered, the observed peak splits in two. In contrast, our ab initio calculations predict that the degeneracy is retained even for WSe2 monolayers. Interestingly, for minuscule biaxial strain, the degeneracy is preserved, but once the crystal symmetry is broken by a small uniaxial strain, the degeneracy is lifted. Our calculated phonon dispersion for uniaxially strained WSe2 shows a good match to the measured Raman spectrum, which suggests that uniaxial strain exists in WSe2 flakes, possibly induced during the sample preparation and/or as a result of the interaction between WSe2 and the substrate. Furthermore, we find that WSe2 undergoes an indirect-to-direct band-gap transition from bulk to monolayers, which is ubiquitous for semiconducting TMDs. These results not only allow us to understand the vibrational and electronic properties of WSe2, but also point to effects of the interaction between the monolayer TMDs and the substrate on the vibrational and electronic properties. DOI: 10.1103/PhysRevB.87.165409
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 365
DOI: 10.1103/PhysRevB.87.165409
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“First-principles investigation of graphene fluoride and graphane”. Leenaerts O, Peelaers H, Hernández-Nieves AD, Partoens B, Peeters FM, Physical review : B : condensed matter and materials physics 82, 195436 (2010). http://doi.org/10.1103/PhysRevB.82.195436
Abstract: Different stoichiometric configurations of graphane and graphene fluoride are investigated within density-functional theory. Their structural and electronic properties are compared, and we indicate the similarities and differences among the various configurations. Large differences between graphane and graphene fluoride are found that are caused by the presence of charges on the fluorine atoms. A configuration that is more stable than the boat configuration is predicted for graphene fluoride. We also perform GW calculations for the electronic band gap of both graphene derivatives. These band gaps and also the calculated Youngs moduli are at variance with available experimental data. This might indicate that the experimental samples contain a large number of defects or are only partially covered with H or F.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 367
DOI: 10.1103/PhysRevB.82.195436
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“Origin of voltage decay in high-capacity layered oxide electrodes”. Sathiya M, Abakumov AM, Foix D, Rousse G, Ramesha K, Saubanère M, Doublet M , Vezin H, Laisa CP, Prakash AS, Gonbeau D, Van Tendeloo G, Tarascon JM, Nature materials 14, 230 (2015). http://doi.org/10.1038/nmat4137
Abstract: Although Li-rich layered oxides (Li1+xNiyCozMn1−x−y−zO2 > 250 mAh g−1) are attractive electrode materials providing energy densities more than 15% higher than todays commercial Li-ion cells, they suffer from voltage decay on cycling. To elucidate the origin of this phenomenon, we employ chemical substitution in structurally related Li2RuO3 compounds. Li-rich layered Li2Ru1−yTiyO3 phases with capacities of ~240 mAh g−1 exhibit the characteristic voltage decay on cycling. A combination of transmission electron microscopy and X-ray photoelectron spectroscopy studies reveals that the migration of cations between metal layers and Li layers is an intrinsic feature of the chargedischarge process that increases the trapping of metal ions in interstitial tetrahedral sites. A correlation between these trapped ions and the voltage decay is established by expanding the study to both Li2Ru1−ySnyO3 and Li2RuO3; the slowest decay occurs for the cations with the largest ionic radii. This effect is robust, and the finding provides insights into new chemistry to be explored for developing high-capacity layered electrodes that evade voltage decay.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 39.737
Times cited: 395
DOI: 10.1038/nmat4137
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“Ordering and phase transitions of charged particles in a classical finite two-dimensional system”. Bedanov VM, Peeters FM, Physical review : B : condensed matter and materials physics 49, 2667 (1994)
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.736
Times cited: 412
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“Bandgap engineering of two-dimensional semiconductor materials”. Chaves A, Azadani JG, Alsalman H, da Costa DR, Frisenda R, Chaves AJ, Song SH, Kim YD, He D, Zhou J, Castellanos-Gomez A, Peeters FM, Liu Z, Hinkle CL, Oh S-H, Ye PD, Koester SJ, Lee YH, Avouris P, Wang X, Low T, npj 2D Materials and Applications 4, 29 (2020). http://doi.org/10.1038/S41699-020-00162-4
Abstract: Semiconductors are the basis of many vital technologies such as electronics, computing, communications, optoelectronics, and sensing. Modern semiconductor technology can trace its origins to the invention of the point contact transistor in 1947. This demonstration paved the way for the development of discrete and integrated semiconductor devices and circuits that has helped to build a modern society where semiconductors are ubiquitous components of everyday life. A key property that determines the semiconductor electrical and optical properties is the bandgap. Beyond graphene, recently discovered two-dimensional (2D) materials possess semiconducting bandgaps ranging from the terahertz and mid-infrared in bilayer graphene and black phosphorus, visible in transition metal dichalcogenides, to the ultraviolet in hexagonal boron nitride. In particular, these 2D materials were demonstrated to exhibit highly tunable bandgaps, achieved via the control of layers number, heterostructuring, strain engineering, chemical doping, alloying, intercalation, substrate engineering, as well as an external electric field. We provide a review of the basic physical principles of these various techniques on the engineering of quasi-particle and optical bandgaps, their bandgap tunability, potentials and limitations in practical realization in future 2D device technologies.
Keywords: A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Times cited: 604
DOI: 10.1038/S41699-020-00162-4
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“From graphene to graphite: electronic structure around the K point”. Partoens B, Peeters FM, Physical review : B : condensed matter and materials physics 74, 075404 (2006). http://doi.org/10.1103/PhysRevB.74.075404
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 738
DOI: 10.1103/PhysRevB.74.075404
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“Adsorption of H2O, NH3, CO, NO2, and NO on graphene: a first-principles study”. Leenaerts O, Partoens B, Peeters FM, Physical review : B : condensed matter and materials physics 77, 125416 (2008). http://doi.org/10.1103/PhysRevB.77.125416
Abstract: Motivated by the recent realization of graphene sensors to detect individual gas molecules, we investigate the adsorption of H2O, NH3, CO, NO2, and NO on a graphene substrate using first-principles calculations. The optimal adsorption position and orientation of these molecules on the graphene surface is determined and the adsorption energies are calculated. Molecular doping, i.e., charge transfer between the molecules and the graphene surface, is discussed in light of the density of states and the molecular orbitals of the adsorbates. The efficiency of doping of the different molecules is determined and the influence of their magnetic moment is discussed.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 1392
DOI: 10.1103/PhysRevB.77.125416
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