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Author Sarmadian, N.; Saniz, R.; Partoens, B.; Lamoen, D.
Title First-principles study of the optoelectronic properties and photovoltaic absorber layer efficiency of Cu-based chalcogenides Type A1 Journal article
Year 2016 Publication Journal of applied physics Abbreviated Journal J Appl Phys
Volume 120 Issue 120 Pages 085707
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
Abstract Cu-based chalcogenides are promising materials for thin-film solar cells with more than 20% measured

cell efficiency. Using first-principles calculations based on density functional theory, the

optoelectronic properties of a group of Cu-based chalcogenides Cu2-II-IV-VI4 is studied. They are

then screened with the aim of identifying potential absorber materials for photovoltaic applications.

The spectroscopic limited maximum efficiency (SLME) introduced by Yu and Zunger [Phys. Rev.

Lett. 108, 068701 (2012)] is used as a metric for the screening. After constructing the currentvoltage

curve, the SLME is calculated from the maximum power output. The role of the nature of

the band gap, direct or indirect, and also of the absorptivity of the studied materials on the maximum

theoretical power conversion efficiency is studied. Our results show that Cu2II-GeSe4 with

II¼ Cd and Hg, and Cu2-II-SnS4 with II ¼ Cd, Hg, and Zn have a higher theoretical efficiency

compared with the materials currently used as absorber layer.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000383913400074 Publication Date 2016-08-30
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 29 Open Access
Notes We acknowledge the financial support from the FWO-Vlaanderen through project G.0150.13N and a GOA fund from the University of Antwerp. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), bothfunded by the FWO-Vlaanderen and the Flemish Government–department EWI. Approved Most recent IF: 2.068
Call Number c:irua:135089 Serial (up) 4113
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Author Pant, A.; Torun, E.; Chen, B.; Bhat, S.; Fan, X.; Wu, K.; Wright, D.P.; Peeters, F.M.; Soignard, E.; Sahin, H.; Tongay, S.
Title Strong dichroic emission in the pseudo one dimensional material ZrS3 Type A1 Journal article
Year 2016 Publication Nanoscale Abbreviated Journal Nanoscale
Volume 8 Issue 8 Pages 16259-16265
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract Zirconium trisulphide (ZrS3), a member of the layered transition metal trichalcogenides (TMTCs) family, has been studied by angle-resolved photoluminescence spectroscopy (ARPLS). The synthesized ZrS3 layers possess a pseudo one-dimensional nature where each layer consists of ZrS3 chains extending along the b-lattice direction. Our results show that the optical properties of few-layered ZrS3 are highly anisotropic as evidenced by large PL intensity variation with the polarization direction. Light is efficiently absorbed when the E-field is polarized along the chain (b-axis), but the field is greatly attenuated and absorption is reduced when it is polarized vertical to the 1D-like chains as the wavelength of the exciting light is much longer than the width of each 1D chain. The observed PL variation with polarization is similar to that of conventional 1D materials, i.e., nanowires, and nanotubes, except for the fact that here the 1D chains interact with each other giving rise to a unique linear dichroism response that falls between the 2D (planar) and 1D (chain) limit. These results not only mark the very first demonstration of PL polarization anisotropy in 2D systems, but also provide novel insight into how the interaction between adjacent 1D-like chains and the 2D nature of each layer influences the overall optical anisotropy of pseudo-1D materials. Results are anticipated to have an impact on optical technologies such as polarized detectors, near-field imaging, communication systems, and bio-applications relying on the generation and detection of polarized light.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000384531600018 Publication Date 2016-08-09
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 54 Open Access
Notes ; S. Tongay gratefully acknowledges support from NSF DMR-1552220. This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). HS is supported by a FWO postdoctoral fellowship. ; Approved Most recent IF: 7.367
Call Number UA @ lucian @ c:irua:144656 Serial (up) 4116
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Author Hill, E.H.; Claes, N.; Bals, S.; Liz-Marzán, L.M.
Title Layered Silicate Clays as Templates for Anisotropic Gold Nanoparticle Growth Type A1 Journal article
Year 2016 Publication Chemistry of materials Abbreviated Journal Chem Mater
Volume 28 Issue 28 Pages 5131-5139
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Clay minerals are abundant natural materials arising in the presence of water and are composed of small particles of different sizes and shapes. The interlamellar space between layered silicate clays can also be used to host a variety of different organic and inorganic guest molecules or particles. Recent studies of clay−metal hybrids formed by impregnation of nanoparticles into the interlayer spaces of the clays have not demonstrated the ability for templated growth following the shape of the particles. Following this line of interest, a method for the synthesis of gold nanoparticles on the synthetic layered silicate clay laponite was developed. This approach can be used to make metal−clay nanoparticles with a variety of morphologies while retaining the molecular adsorption properties of the clay. The surface enhanced Raman scattering enhancement of these particles was also found to be greater than that obtained from other metal nanoparticles of a similar morphology, likely due to increased dye adsorption by the presence of the clay. The hybrid particles presented herein will contribute to further study of plasmonic

sensing, catalysis, dye aggregation, and novel composite materials.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000380576700031 Publication Date 2016-07-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0897-4756 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 9.466 Times cited 13 Open Access OpenAccess
Notes This work has been supported by the European Research Council (ERC Advanced Grant No. 267867, PLASMAQUO). E.H.H. thanks the Spanish Ministry of Economy and Competitiveness for providing a Juan de la Cierva Fellowship (FJCI-2014-22598). N.C. and S.B. acknowledge financial support from European Research Council (ERC Starting Grant #335078-COLOURATOM). We gratefully acknowledge A. B. Serrano-Montes for providing the seed-mediated Au nanostars.; ECAS_Sara; (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); Approved Most recent IF: 9.466
Call Number c:irua:135178 c:irua:135178 Serial (up) 4117
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Author De Keukeleere, K.; Cayado, P.; Meledin, A.; Vallès, F.; De Roo, J.; Rijckaert, H.; Pollefeyt, G.; Bruneel, E.; Palau, A.; Coll, M.; Ricart, S.; Van Tendeloo, G.; Puig, T.; Obradors, X.; Van Driessche, I.
Title Superconducting YBa2Cu3O7-δNanocomposites Using Preformed ZrO2Nanocrystals: Growth Mechanisms and Vortex Pinning Properties Type A1 Journal article
Year 2016 Publication Advanced Electronic Materials Abbreviated Journal
Volume 2 Issue 2 Pages 1600161
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Although high temperature superconductors are promising for power applications, the production of low-cost coated conductors with high current densities—at high magnetic fields—remains challenging. A superior superconducting YBa2Cu3O7–δ nanocomposite is fabricated via chemical solution deposition (CSD) using preformed nanocrystals (NCs). Preformed, colloidally stable ZrO2 NCs are added to the trifluoroacetic acid based precursor solution and the NCs' stability is confirmed up to 50 mol% for at least 2.5 months. These NCs tend to disrupt the epitaxial growth of YBa2Cu3O7–δ, unless a thin seed layer is applied. A 10 mol% ZrO2 NC addition proved to be optimal, yielding a critical current density JC of 5 MA cm−2 at 77 K in self-field. Importantly, this new approach results in a smaller magnetic field decay of JC(H//c) for the nanocomposite compared to a pristine film. Furthermore, microstructural analysis of the YBa2Cu3O7–δ nanocomposite films reveals that different strain generation mechanisms may occur compared to the spontaneous segregation approach. Yet, the generated nanostrain in the YBa2Cu3O7–δ nanocomposite results in an improvement of the superconducting properties similar to the spontaneous segregation approach. This new approach, using preformed NCs in CSD coatings, can be of great potential for high magnetic field applications.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000386624100003 Publication Date 2016-09-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2199160X ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 26 Open Access
Notes This work was financially supported by a BOF research fund of Ghent University (BOF11/DOC/286), FWO Flanders (F08512), and Eurotapes, a collaborative project funded by the European Community’s Seven Framework Program (EU-FP7 NMP-LA-2012-280432). We also acknowledge MINECO and FEDER funds for MAT2014-51778-C2-1-R and the Center of Excellence award Severo Ochoa SEV-2015-0496, and SGR753 from the Generalitat of Catalunya. MC acknowledges RyC contract 2013-12448 Approved Most recent IF: NA
Call Number EMAT @ emat @ c:irua:135171 Serial (up) 4118
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Author Sankaran, K.J.; Hoang, D.Q.; Kunuku, S.; Korneychuk, S.; Turner, S.; Pobedinskas, P.; Drijkoningen, S.; Van Bael, M.K.; D' Haen, J.; Verbeeck, J.; Leou, K.-C.; Lin, I.-N.; Haenen, K.
Title Enhanced optoelectronic performances of vertically aligned hexagonal boron nitride nanowalls-nanocrystalline diamond heterostructures Type A1 Journal article
Year 2016 Publication Scientific reports Abbreviated Journal Sci Rep-Uk
Volume 6 Issue 6 Pages 29444
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Field electron emission (FEE) properties of vertically aligned hexagonal boron nitride nanowalls (hBNNWs) grown on Si have been markedly enhanced through the use of nitrogen doped nanocrystalline diamond (nNCD) films as an interlayer. The FEE properties of hBNNWs-nNCD heterostructures show a low turn-on field of 15.2 V/mum, a high FEE current density of 1.48 mA/cm(2) and life-time up to a period of 248 min. These values are far superior to those for hBNNWs grown on Si substrates without the nNCD interlayer, which have a turn-on field of 46.6 V/mum with 0.21 mA/cm(2) FEE current density and life-time of 27 min. Cross-sectional TEM investigation reveals that the utilization of the diamond interlayer circumvented the formation of amorphous boron nitride prior to the growth of hexagonal boron nitride. Moreover, incorporation of carbon in hBNNWs improves the conductivity of hBNNWs. Such a unique combination of materials results in efficient electron transport crossing nNCD-to-hBNNWs interface and inside the hBNNWs that results in enhanced field emission of electrons. The prospective application of these materials is manifested by plasma illumination measurements with lower threshold voltage (370 V) and longer life-time, authorizing the role of hBNNWs-nNCD heterostructures in the enhancement of electron emission.
Address IMOMEC, IMEC vzw, 3590 Diepenbeek, Belgium
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Wos 000379391000001 Publication Date 2016-07-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2045-2322 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.259 Times cited 15 Open Access
Notes The authors like to thank the financial support of the Research Foundation Flanders (FWO) via Research Project G.0456.12, G0044.13N and the Methusalem “NANO” network. Kamatchi Jothiramalingam Sankaran, Stuart Turner, and Paulius Pobedinskas are Postdoctoral Fellows of the Research Foundations Flanders (FWO). Approved Most recent IF: 4.259
Call Number c:irua:134643 c:irua:134643UA @ admin @ c:irua:134643 Serial (up) 4119
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Author Ekimov, E.A.; Kudryavtsev, O.S.; Turner, S.; Korneychuk, S.; Sirotinkin, V.P.; Dolenko, T.A.; Vervald, A.M.; Vlasov, I.I.
Title The effect of molecular structure of organic compound on the direct high-pressure synthesis of boron-doped nanodiamond: Effect of organic compound on synthesis of boron-doped nanodiamond Type A1 Journal article
Year 2016 Publication Physica status solidi : A : applications and materials science Abbreviated Journal Phys Status Solidi A
Volume 213 Issue 213 Pages 2582-2589
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Evolution of crystalline phases with temperature has been studied in materials produced by high-pressure high-temperature treatment of 9-borabicyclo[3.3.1]nonane dimer (9BBN), triphenylborane and trimesitylborane. The boron-doped diamond nanoparticles with a size below 10 nm were obtained at 8–9 GPa and temperatures 970–1250 °C from 9BBN only. Bridged structure and the presence of boron atom in the carbon cycle of 9BBN were revealed to be a key point for the direct synthesis of doped diamond nanocrystals. The diffusional transformation of the disordered carbon phase is suggested to be the main mechanism of the nanodiamond formation from 9BBN in the temperature range of 970–1400 °C. Aqueous suspensions of primary boron-doped diamond nanocrystals were prepared upon removal of non-diamond phases that opens wide opportunities for application of this new nanomaterial in electronics and biotechnologies.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000388321500006 Publication Date 2016-07-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1862-6300 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.775 Times cited 8 Open Access
Notes Approved Most recent IF: 1.775
Call Number EMAT @ emat @ c:irua:135175 Serial (up) 4120
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Author Turner, S.; Idrissi, H.; Sartori, A.F.; Korneychuck, S.; Lu, Y.-G.; Verbeeck, J.; Schreck, M.; Van Tendeloo, G.
Title Direct imaging of boron segregation at dislocations in B:diamond heteroepitaxial films Type A1 Journal article
Year 2016 Publication Nanoscale Abbreviated Journal Nanoscale
Volume 8 Issue 8 Pages 2212-2218
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract A thin film of heavily B-doped diamond has been grown epitaxially by microwave plasma chemical vapor deposition on an undoped diamond layer, on top of a Ir/YSZ/Si(001) substrate stack, to study the boron segregation and boron environment at the dislocations present in the film. The density and nature of the dislocations were investigated by conventional and weak-beam dark-field transmission electron microscopy techniques, revealing the presence of two types of dislocations: edge and mixed-type 45 degrees dislocations. The presence and distribution of B in the sample was studied using annular dark-field scanning transmission electron microscopy and spatially resolved electron energy-loss spectroscopy. Using these techniques, a segregation of B at the dislocations in the film is evidenced, which is shown to be intermittent along the dislocation. A single edge-type dislocation was selected to study the distribution of the boron surrounding the dislocation core. By imaging this defect at atomic resolution, the boron is revealed to segregate towards the tensile strain field surrounding the edge-type dislocations. An investigation of the fine structure of the B-K edge at the dislocation core shows that the boron is partially substitutionally incorporated into the diamond lattice and partially present in a lower coordination (sp(2)-like hybridization).
Address EMAT, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp, Belgium. stuart.turner@uantwerpen.be
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Wos 000368860900053 Publication Date 2015-12-21
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 15 Open Access
Notes S. T. acknowledges the fund for scien tific research Flanders (FWO) for a post-doctoral scholarship and under contract number G.0044.13N Approved Most recent IF: 7.367
Call Number c:irua:131597UA @ admin @ c:irua:131597 Serial (up) 4121
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Author Babynina, A.; Fedoruk, M.; Kuhler, P.; Meledin, A.; Doblinger, M.; Lohmueller, T.
Title Bending Gold Nanorods with Light Type A1 Journal article
Year 2016 Publication Nano letters Abbreviated Journal Nano Lett
Volume 16 Issue 16 Pages 6485-6490
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract V-shaped gold nanoantennas are the functional components of plasmonic metasurfaces, which are capable of manipulating light in unprecedented ways. Designing a metasurface requires the custom arrangement of individual antennas with controlled shape and orientation. Here, we show how highly crystalline gold nanorods in solution can be bend, one-by one, into a V-shaped geometry and printed to the surface of a solid support through a combination of plasmonic heating and optical force. Significantly, we demonstrate that both the bending angle and the orientation of each rod-antenna can be adjusted independent from each other by tuning the laser intensity and polarization. This approach is applicable for the patterning of V-shaped plasmonic antennas on almost any substrate, which holds great potential for the fabrication of ultrathin optical components and devices.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Wos 000385469800072 Publication Date 2016-09-06
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 24 Open Access
Notes PMID:27598653 We would also like to thank Prof. Jochen Feldmann and Bernhard Bohn for fruitful discussions. Approved Most recent IF: 12.712
Call Number c:irua:135172 Serial (up) 4122
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Author Goris, B.; Meledina, M.; Turner, S.; Zhong, Z.; Batenburg, K.J.; Bals, S.
Title Three dimensional mapping of Fe dopants in ceria nanocrystals using direct spectroscopic electron tomography Type A1 Journal article
Year 2016 Publication Ultramicroscopy Abbreviated Journal Ultramicroscopy
Volume 171 Issue 171 Pages 55-62
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Electron tomography is a powerful technique for the 3D characterization of the morphology of nanostructures. Nevertheless, resolving the chemical composition of complex nanostructures in 3D remains challenging and the number of studies in which electron energy loss spectroscopy (EELS) is combined with tomography is limited. During the last decade, dedicated reconstruction algorithms have been developed for HAADF-STEM tomography using prior knowledge about the investigated sample. Here, we will use the prior knowledge that the experimental spectrum of each reconstructed voxel is a linear combination of a well-known set of references spectra in a so-called direct spectroscopic tomography technique. Based on a simulation experiment, it is shown that this technique provides superior results in comparison to conventional reconstruction methods for spectroscopic data, especially for spectrum images containing a relatively low signal to noise ratio. Next, this technique is used to investigate the spatial distribution of Fe dopants in Fe:Ceria nanoparticles in 3D. It is shown that the presence of the Fe2+ dopants is correlated with a reduction of the Ce atoms from Ce4+ towards Ce3+. In addition, it is demonstrated that most of the Fe dopants are located near the voids inside the nanoparticle.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000389106200007 Publication Date 2016-09-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0304-3991 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.843 Times cited 13 Open Access OpenAccess
Notes The work was supported by the Research Foundation Flanders (FWO Vlaanderen) by project funding (G038116N, 3G004613) and by a post-doctoral research grants to B.G. S.B. acknowledges funding from the European Research Council (Starting Grant no. COLOURATOMS 335078). K.J.B. acknowledges funding from The Netherlands Organization for Scientific Research (NWO) (program 639.072.005.). We would like to thank Dr. Hilde Poelman, Dr. Vladimir Galvita and Prof. Dr. Guy B. Marin for the synthesis of the investigated sample.; ECAS_Sara; (ROMEO:green; preprint:; postprint:can ; pdfversion:cannot); Approved Most recent IF: 2.843
Call Number c:irua:135185 c:irua:135185 Serial (up) 4123
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Author Kirilenko, D.A.; Brunkov, P.N.
Title Measuring the height-to-height correlation function of corrugation in suspended graphene Type A1 Journal article
Year 2016 Publication Ultramicroscopy Abbreviated Journal Ultramicroscopy
Volume 165 Issue 165 Pages 1-7
Keywords A1 Journal article; Electron Microscopy for Materials Science (EMAT);
Abstract Nanocorrugation of 2D crystals is an important phenomenon since it affects their electronic and mechanical properties. The corrugation may have various sources; one of them is flexural phonons that, in particular, are responsible for the thermal conductivity of graphene. A study of corrugation of just the suspended graphene can reveal much of valuable information on the physics of this complicated phenomenon. At the same time, the suspended crystal nanorelief can hardly be measured directly because of high flexibility of the 2D crystal. Moreover, the relief portion related to rapid out-of-plane oscillations (flexural phonons) is also inaccessible by such measurements. Here we present a technique for measuring the Fourier components of the height-height correlation function H(q) of suspended graphene which includes the effect of flexural phonons. The technique is based on the analysis of electron diffraction patterns. The H(q) is measured in the range of wavevectors q approximately 0.4-4.5nm(-1). At the upper limit of this range H(q) does follow the T/kappaq(4) law. So, we measured the value of suspended graphene bending rigidity kappa=1.2+/-0.4eV at ambient temperature T approximately 300K. At intermediate wave vectors, H(q) follows a slightly weaker exponent than theoretically predicted q(-3.15) but is closer to the results of the molecular dynamics simulation. At low wave vectors, the dependence becomes even weaker, which may be a sign of influence of charge carriers on the dynamics of undulations longer than 10nm. The technique presented can be used for studying physics of flexural phonons in other 2D materials.
Address Ioffe Institute, Politekhnicheskaya ul. 26, 194021 St-Petersburg, Russia; ITMO University, Kronverksky pr. 49, 197101 St. Petersburg, Russia
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Wos 000375946200001 Publication Date 2016-03-28
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0304-3991 ISBN Additional Links
Impact Factor 2.843 Times cited 3 Open Access
Notes D.K. thanks the RFBR (Grant no. 16-32-60165) for the partial support of this research. The work was carried out in part at the Joint Research Center “Material Science and Characterization in Advanced Technologies” (St-Petersburg, Russia) under the financial support from the Ministry of Education and Science of the Russian Federation (Agreement 14.621.21.0007, 04.12.2014, id RFMEFI62114X0007, the use of the Jeol JEM-2100F microscope) and at EMAT, Universiteit Antwerpen (Antwerpen, Belgium), (the use of the FEI Tecnai G2 microscope). Approved Most recent IF: 2.843
Call Number EMAT @ emat @ Serial (up) 4124
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Author Sobrino Fernandez, M.M.; Neek-Amal, M.; Peeters, F.M.
Title 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 (up) 4127
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Author Gonnissen, J.; De Backer, A.; den Dekker, A.J.; Sijbers, J.; Van Aert, S.
Title Detecting and locating light atoms from high-resolution STEM images: The quest for a single optimal design Type A1 Journal article
Year 2016 Publication Ultramicroscopy Abbreviated Journal Ultramicroscopy
Volume 170 Issue 170 Pages 128-138
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab
Abstract In the present paper, the optimal detector design is investigated for both detecting and locating light atoms from high resolution scanning transmission electron microscopy (HR STEM) images. The principles of detection theory are used to quantify the probability of error for the detection of light atoms from HR STEM images. To determine the optimal experiment design for locating light atoms, use is made of the so-called Cramer-Rao Lower Bound (CRLB). It is investigated if a single optimal design can be found for both the detection and location problem of light atoms. Furthermore, the incoming electron dose is optimised for both research goals and it is shown that picometre range precision is feasible for the estimation of the atom positions when using an appropriate incoming electron dose under the optimal detector settings to detect light atoms.
Address Electron Microscopy for Materials Science (EMAT), University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp, Belgium. Electronic address: sandra.vanaert@uantwerpen.be
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Wos 000386925500014 Publication Date 2016-07-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0304-3991 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.843 Times cited 6 Open Access
Notes The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0368.15, G.0369.15 and G.0374.13) and a postdoctoral research grant to A. De Backer. The research leading to these results has also received funding from the European Union Seventh Framework Programme [FP7/2007-2013] under Grant agreement no. 312483 (ESTEEM2). The authors would also like to thank A. Rosenauer for providing access to the STEMsim software and Gerardo T. Martinez for fruitful discussions.; esteem2_jra2 Approved Most recent IF: 2.843
Call Number c:irua:135337 c:irua:135337 Serial (up) 4128
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Author Gonnissen, J.; Batuk, D.; Nataf, G.F.; Jones, L.; Abakumov, A.M.; Van Aert, S.; Schryvers, D.; Salje, E.K.H.
Title Direct Observation of Ferroelectric Domain Walls in LiNbO3: Wall-Meanders, Kinks, and Local Electric Charges Type A1 Journal article
Year 2016 Publication Advanced functional materials Abbreviated Journal Adv Funct Mater
Volume 26 Issue 26 Pages 7599-7604
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Direct observations of the ferroelectric domain boundaries in LiNbO3 are performed using high-resolution high-angle annular dark field scanning transmission electron microscopy imaging, revealing a very narrow width of the domain wall between the 180° domains. The domain walls demonstrate local side-way meandering, which results in inclinations even when the overall wall orientation follows the ferroelectric polarization. These local meanders contain kinks with “head-to-head” and “tail-to-tail” dipolar configurations and are therefore locally charged. The charged meanders are confined to a few cation layers along the polarization direction and are separated by longer stretches of straight domain walls.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000388166700006 Publication Date 2016-09-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1616-301X ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 12.124 Times cited 23 Open Access
Notes J.G. acknowledges the support from the Research Foundation Flanders (FWO, Belgium) through various project fundings (G.0368.15N, G.0369.15N, and G.0374.13N), as well as the financial support from the European Union Seventh Framework Program (FP7/2007–2013) under Grant agreement no. 312483 (ESTEEM2). The authors thank J. Hadermann for useful suggestions on the interpretation of the HAADFSTEM images. E.K.H.S. thanks the EPSRC (EP/K009702/1) and the Leverhulme Trust (EM-2016-004) for support. G.F.N. thanks the National Research Fund, Luxembourg (FNR/P12/4853155/Kreisel) for support.; esteem2_jra2 Approved Most recent IF: 12.124
Call Number c:irua:135336 c:irua:135336 Serial (up) 4129
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Author Spadaro, M.C.; Luches, P.; Bertoni, G.; Grillo, V.; Turner, S.; Van Tendeloo, G.; Valeri, S.; D'Addato, S.
Title Influence of defect distribution on the reducibility of CeO2-x nanoparticles Type A1 Journal article
Year 2016 Publication Nanotechnology Abbreviated Journal Nanotechnology
Volume 27 Issue 27 Pages 425705
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Ceria nanoparticles (NPs) are fundamental in heterogeneous catalysis because of their ability to store or release oxygen depending on the ambient conditions. Their oxygen storage capacity is strictly related to the exposed planes, crystallinity, density and distribution of defects. In this work a study of ceria NPs produced with a ligand-free, physical synthesis method is presented. The NP films were grown by a magnetron sputtering based gas aggregation source and studied by high resolution- and scanning-transmission electron microscopy and x-ray photoelectron spectroscopy. In particular, the influence of the oxidation procedure on the NP reducibility has been investigated. The different reducibility has been correlated to the exposed planes, crystallinity and density and distribution of structural defects. The results obtained in this work represent a basis to obtain cerium oxide NP with desired oxygen transport properties.
Address Dipartimento FIM, Universita di Modena e Reggio Emilia, via G. Campi 213/a, I-41125 Modena, Italy. CNR-NANO, via G. Campi 213/a, I-41125 Modena, Italy
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Wos 000385483900004 Publication Date 2016-09-15
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0957-4484 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.44 Times cited 11 Open Access
Notes The authors gratefully acknowledge financial support by the Italian MIUR under grant FIRB RBAP115AYN (Oxides at the nanoscale: multifunctionality and applications). The activity is performed within the COST Action CM1104 'Reducible oxide chemistry, structure and functions'. The research leading to these results has received funding also from the European Union Seventh Framework Programme under Grant Agreement 312483—ESTEEM2 (Integrated Infrastructure Initiative–I3).; esteem2_ta Approved Most recent IF: 3.44
Call Number EMAT @ emat @ c:irua:135424 Serial (up) 4130
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Author Aierken, Y.; Leenaerts, O.; Peeters, F.M.
Title A first-principles study of stable few-layer penta-silicene Type A1 Journal article
Year 2016 Publication Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys
Volume 18 Issue 18 Pages 18486-18492
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Recently penta-graphene was proposed as a stable two-dimensional carbon allotrope consisting of a single layer of interconnected carbon pentagons [Zhang et al., PNAS, 2015, 112, 2372]. Its silicon counterpart, penta-silicene, however, is not stable. In this work, we show that multilayers of penta-silicene form stable materials with semiconducting or metallic properties, depending on the stacking mode. We demonstrate their dynamic stability through their phonon spectrum and using molecular dynamics. A particular type of bilayer penta-silicene is found to have lower energy than all of the known hexagonal silicene bilayers and forms therefore the most stable bilayer silicon material predicted so far. The electronic and mechanical properties of these new silicon allotropes are studied in detail and their behavior under strain is investigated. We demonstrate that strain can be used to tune its band gap.
Address
Corporate Author Thesis
Publisher Place of Publication Cambridge Editor
Language Wos 000379486200077 Publication Date 2016-06-15
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1463-9076 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.123 Times cited 42 Open Access
Notes ; This work was supported by the Fonds Wetenschappelijk Onderzoek (FWO-Vl). The computational resources used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the Hercules Foundation and the Flemish Government-department EWI. ; Approved Most recent IF: 4.123
Call Number UA @ lucian @ c:irua:134942 Serial (up) 4132
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Author Paolella, A.; Turner, S.; Bertoni, G.; Hovington, P.; Flacau, R.; Boyer, C.; Feng, Z.; Colombo, M.; Marras, S.; Prato, M.; Manna, L.; Guerfi, A.; Demopoulos, G.P.; Armand, M.; Zaghib, K.;
Title Accelerated removal of Fe-antisite defects while nanosizing hydrothermal LiFePO4 with Ca2+ Type A1 Journal article
Year 2016 Publication Nano letters Abbreviated Journal Nano Lett
Volume 16 Issue 16 Pages 2692-2697
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Based on neutron powder diffraction (NPD) and high angle annular dark field scanning transmission electron microscopy (HAADF-STEM), we show that calcium ions help eliminate the Fe-antisite defects by controlling the nucleation and evolution of the LiFePO4 particles during their hydrothermal synthesis. This Ca-regulated formation of LiFePO4 particles has an overwhelming impact on the removal of their iron antisite defects during the subsequent carbon coating step since (i) almost all the Fe-antisite defects aggregate at the surface of the LiFePO4 crystal when the crystals are small enough and (ii) the concomitant increase of the surface area, which further exposes the Fe-antisite defects. Our results not only justify a low-cost, efficient and reliable hydrothermal synthesis method for LiFePO4 but also provide a promising alternative viewpoint on the mechanism controlling the nanosizing of LiFePO4, which leads to improved electrochemical performances.
Address
Corporate Author Thesis
Publisher Place of Publication Washington Editor
Language Wos 000374274600084 Publication Date 2016-03-11
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 30 Open Access
Notes Approved Most recent IF: 12.712
Call Number UA @ lucian @ c:irua:133600 Serial (up) 4134
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Author Zhong, R.; Peng, L.; de Clippel, F.; Gommes, C.; Goderis, B.; Ke, X.; Van Tendeloo, G.; Jacobs, P.A.; Sels, B.F.
Title An eco-friendly soft template synthesis of mesostructured silica-carbon nanocomposites for acid catalysis Type A1 Journal article
Year 2015 Publication ChemCatChem Abbreviated Journal Chemcatchem
Volume 7 Issue 7 Pages 3047-3058
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The synthesis of ordered mesoporous silica-carbon composites was explored by employing TEOS and sucrose as the silica and carbon precursor respectively, and the triblock copolymer F127 as a structure-directing agent via an evaporation-induced self-assembly (EISA) process. It is demonstrated that the synthesis procedures allow for control of the textural properties and final composition of these silica-carbon nanocomposites via adjustment of the effective SiO2/C weight ratio. Characterization by SAXS, N-2 physisorption, HRTEM, TGA, and C-13 and Si-29 solid-state MAS NMR show a 2D hexagonal mesostructure with uniform large pore size ranging from 5.2 to 7.6nm, comprising of separate carbon phases in a continuous silica phase. Ordered mesoporous silica and non-ordered porous carbon can be obtained by combustion of the pyrolyzed nanocomposites in air or etching with HF solution, respectively. Sulfonic acid groups can be readily introduced to such kind of silica-carbon nanocomposites by a standard sulfonation procedure with concentrated sulfuric acid. Excellent acid-catalytic activities and selectivities for the dimerization of styrene to produce 1,3-diphenyl-1-butene and dimerization of -methylstyrene to unsaturated dimers were demonstrated with the sulfonated materials.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000361189400037 Publication Date 2015-09-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1867-3880; 1867-3899 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.803 Times cited 13 Open Access
Notes Approved Most recent IF: 4.803; 2015 IF: 4.556
Call Number UA @ lucian @ c:irua:127836 Serial (up) 4138
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Author Arsoski, V.V.; Čukarić, N.A.; Tadic, M.Z.; Peeters, F.M.
Title An efficient finite-difference scheme for computation of electron states in free-standing and core-shell quantum wires Type A1 Journal article
Year 2015 Publication Computer physics communications Abbreviated Journal Comput Phys Commun
Volume 197 Issue 197 Pages 17-26
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The electron states in axially symmetric quantum wires are computed by means of the effective-mass Schrodinger equation, which is written in cylindrical coordinates phi, rho, and z. We show that a direct discretization of the Schrodinger equation by central finite differences leads to a non-symmetric Hamiltonian matrix. Because diagonalization of such matrices is more complex it is advantageous to transform it in a symmetric form. This can be done by the Liouville-like transformation proposed by Rizea et al. (2008), which replaces the wave function psi(rho) with the function F(rho) = psi(rho)root rho and transforms the Hamiltonian accordingly. Even though a symmetric Hamiltonian matrix is produced by this procedure, the computed wave functions are found to be inaccurate near the origin, and the accuracy of the energy levels is not very high. In order to improve on this, we devised a finite-difference scheme which discretizes the Schrodinger equation in the first step, and then applies the Liouville-like transformation to the difference equation. Such a procedure gives a symmetric Hamiltonian matrix, resulting in an accuracy comparable to the one obtained with the finite element method. The superior efficiency of the new finite-difference scheme (FDM) is demonstrated for a few p-dependent one-dimensional potentials which are usually employed to model the electron states in free-standing and core shell quantum wires. The new scheme is compared with the other FDM schemes for solving the effective-mass Schrodinger equation, and is found to deliver energy levels with much smaller numerical error for all the analyzed potentials. It also gives more accurate results than the scheme of Rizea et al., except for the ground state of an infinite rectangular potential in freestanding quantum wires. Moreover, the PT symmetry is invoked to explain similarities and differences between the considered FDM schemes. (C) 2015 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000362919500003 Publication Date 2015-08-08
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0010-4655 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.936 Times cited 4 Open Access
Notes ; This work was supported by the Ministry of Education, Science, and Technological Development of Serbia (project III 45003) and the Fonds Wetenschappelijk Onderzoek (Belgium). ; Approved Most recent IF: 3.936; 2015 IF: 3.112
Call Number UA @ lucian @ c:irua:129412 Serial (up) 4139
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Author Chaves, A.; Low, T.; Avouris, P.; Çakir, D.; Peeters, F.M.
Title Anisotropic exciton Stark shift in black phosphorus 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 155311
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We calculate the excitonic spectrum of few-layer black phosphorus by direct diagonalization of the effective mass Hamiltonian in the presence of an applied in-plane electric field. The strong attractive interaction between electrons and holes in this system allows one to investigate the Stark effect up to very high ionizing fields, including also the excited states. Our results show that the band anisotropy in black phosphorus becomes evident in the direction-dependent field-induced polarizability of the exciton.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000353459200005 Publication Date 2015-04-27
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 88 Open Access
Notes ; Discussions with J. M. Pereira Jr. and J. S. de Souza are gratefully acknowledged. This work was supported by the Brazilian Council for Research (CNPq) through the PQ and Science Without Borders programs, the Flemish Science Foundation (FWO-Vl), the Methusalem programme of the Flemish government, and the Bilateral program (CNPq-FWO) between Flanders and Brazil. ; Approved Most recent IF: 3.836; 2015 IF: 3.736
Call Number UA @ lucian @ c:irua:132506 Serial (up) 4141
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Author Guidini, A.; Flammia, L.; Milošević, M.V.; Perali, A.
Title BCS-BEC crossover in quantum confined superconductors Type A1 Journal article
Year 2016 Publication Journal of superconductivity and novel magnetism Abbreviated Journal J Supercond Nov Magn
Volume 29 Issue 29 Pages 711-715
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Ultranarrow superconductors are in the strong quantum confinement regime with formation of multiple coherent condensates associated with the many subbands of the electronic structure. Here, we analyze the multiband BCS-BEC crossover induced by the chemical potential tuned close to a subband bottom, in correspondence of a superconducting shape resonance. The evolution of the condensate fraction and of the pair correlation length in the ground state as functions of the chemical potential demonstrates the tunability of the BCS-BEC crossover for the condensate component of the selected subband. The extension of the crossover regime increases when the pairing strength and/or the characteristic energy of the interaction get larger. Our results indicate the coexistence of large and small Cooper pairs in the crossover regime, leading to the optimal parameter configuration for high transition temperature superconductivity.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000371089500034 Publication Date 2015-12-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1557-1939 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.18 Times cited 12 Open Access
Notes ; We acknowledge A. Bianconi and A.A. Shanenko for useful discussions. A.P. acknowledges financial support from the University of Camerino under the project FAR “Control and enhancement of superconductivity by engineering materials at the nanoscale”. M.V.M. acknowledges support from the Research Foundation – Flanders (FWO) and the Special Research Funds of the University of Antwerp (BOF-UA). A.P. and M.V.M. acknowledge the collaboration within the MultiSuper International Network (http://www.multisuper.org) for exchange of ideas and suggestions. ; Approved Most recent IF: 1.18
Call Number UA @ lucian @ c:irua:132287 Serial (up) 4143
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Author Bacaksiz, C.; Cahangirov, S.; Rubio, A.; Senger, R.T.; Peeters, F.M.; Sahin, H.
Title Bilayer SnS2 : tunable stacking sequence by charging and loading pressure Type A1 Journal article
Year 2016 Publication Physical review B Abbreviated Journal Phys Rev B
Volume 93 Issue 93 Pages 125403
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Employing density functional theory-based methods, we investigate monolayer and bilayer structures of hexagonal SnS2, which is a recently synthesized monolayer metal dichalcogenide. Comparison of the 1H and 1T phases of monolayer SnS2 confirms the ground state to be the 1T phase. In its bilayer structure we examine different stacking configurations of the two layers. It is found that the interlayer coupling in bilayer SnS2 is weaker than that of typical transition-metal dichalcogenides so that alternative stacking orders have similar structural parameters and they are separated with low energy barriers. A possible signature of the stacking order in the SnS2 bilayer has been sought in the calculated absorbance and reflectivity spectra. We also study the effects of the external electric field, charging, and loading pressure on the characteristic properties of bilayer SnS2. It is found that (i) the electric field increases the coupling between the layers at its preferred stacking order, so the barrier height increases, (ii) the bang gap value can be tuned by the external E field and under sufficient E field, the bilayer SnS2 can become a semimetal, (iii) the most favorable stacking order can be switched by charging, and (iv) a loading pressure exceeding 3 GPa changes the stacking order. The E-field tunable band gap and easily tunable stacking sequence of SnS2 layers make this 2D crystal structure a good candidate for field effect transistor and nanoscale lubricant applications.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000371405000005 Publication Date 2016-03-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2469-9950;2469-9969; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 38 Open Access
Notes ; The calculations were performed at TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). C.B., H.S., and R.T.S. acknowledge support from TUBITAK Project No. 114F397. H.S. is supported by an FWO Pegasus Marie Curie Fellowship. S.C. and A.R. acknowledge financial support from the Marie Curie grant FP7-PEOPLE-2013-IEF Project No. 628876, the European Research Council (ERC-2010-AdG-267374), and Spanish grant Grupos Consolidados (IT578-13). S.C. acknowledges support from the Scientific and Technological Research Council of Turkey (TUBITAK) under Project No. 115F388. ; Approved Most recent IF: 3.836
Call Number UA @ lucian @ c:irua:132345 Serial (up) 4144
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Author Van Aelst, J.; Verboekend, D.; Philippaerts, A.; Nuttens, N.; Kurttepeli, M.; Gobechiya, E.; Haouas, M.; Sree, S.P.; Denayer, J.F.M.; Martens, J.A.; Kirschhock, C.E.A.; Taulelle, F.; Bals, S.; Baron, G.V.; Jacobs, P.A.; Sels, B.F.
Title Catalyst design by NH4OH treatment of USY zeolite Type A1 Journal article
Year 2015 Publication Advanced functional materials Abbreviated Journal Adv Funct Mater
Volume 25 Issue 25 Pages 7130-7144
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Hierarchical zeolites are a class of superior catalysts which couples the intrinsic zeolitic properties to enhanced accessibility and intracrystalline mass transport to and from the active sites. The design of hierarchical USY (Ultra-Stable Y) catalysts is achieved using a sustainable postsynthetic room temperature treatment with mildly alkaline NH4OH ( 0.02(M)) solutions. Starting from a commercial dealuminated USY zeolite (Si/Al = 47), a hierarchical material is obtained by selective and tuneable creation of interconnected and accessible small mesopores (2- 6 nm). In addition, the treatment immediately yields the NH4+ form without the need for additional ion exchange. After NH4OH modification, the crystal morphology is retained, whereas the microporosity and relative crystallinity are decreased. The gradual formation of dense amorphous phases throughout the crystal without significant framework atom leaching rationalizes the very high material yields (>90%). The superior catalytic performance of the developed hierarchical zeolites is demonstrated in the acid-catalyzed isomerization of alpha-pinene and the metal-catalyzed conjugation of safflower oil. Significant improvements in activity and selectivity are attained, as well as a lowered susceptibility to deactivation. The catalytic performance is intimately related to the introduced mesopores, hence enhanced mass transport capacity, and the retained intrinsic zeolitic properties.
Address
Corporate Author Thesis
Publisher Place of Publication Weinheim Editor
Language Wos 000366503700003 Publication Date 2015-10-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1616-301x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 12.124 Times cited 64 Open Access OpenAccess
Notes ; The authors thank Dr. M. Thommes and Dr. K. Cychosz for numerous and helpful discussions on the correct evaluation of the Ar isotherms. I. Cuppens is acknowledged for ICP-AES analyses. Research was funded through a PhD grant to J.V.A. of the Agency for Innovation by Science and Technology in Flanders (IWT). D.V. and A.P. acknowledge F.W.O.-Vlaanderen (Research Foundation Flanders) for a postdoctoral fellowship. N.N. thanks the KU Leuven for financial support (FLOF). E.G., C.K., and J.M. acknowledge the long-term structural funding by the Flemish Government (Methusalem). S.B. acknowledges the European Research Council for funding under the European Union's Seventh Framework Programme (FP7/2007-2013)/ERC grant agreement No. 335078-COLOURATOMS. The authors are grateful for financial support by the Belgian government through Interuniversity Attraction Poles (IAP-PAI). They also thank Oleon NV for supplying safflower oil. ; ecas_Sara Approved Most recent IF: 12.124; 2015 IF: 11.805
Call Number UA @ lucian @ c:irua:130214 Serial (up) 4147
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Author Galvan-Moya; Misko, V.R.; Peeters, F.M.
Title Chainlike transitions in Wigner crystals : sequential versus nonsequential 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 064112
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The structural transitions of the ground state of a system of repulsively interacting particles confined in a quasi-one-dimensional channel, and the effect of the interparticle interaction as well as the functional form of the confinement potential on those transitions are investigated. Although the nonsequential ordering of transitions (non-SOT), i.e., the 1 – 2 – 4 – 3 – 4 – 5 – 6 – ... sequence of chain configurations with increasing density, is widely robust as predicted in a number of theoretical studies, the sequential ordering of transitions (SOT), i.e., the 1 – 2 – 3 – 4 – 5 – 6 – ... chain, is found as the ground state for long-ranged interparticle interaction and hard-wall-like confinement potentials. We found an energy barrier between every two different phases around its transition point, which plays an important role in the preference of the system to follow either a SOT or a non-SOT. However, that preferential transition requires also the stability of the phases during the transition. Additionally, we analyze the effect of a small structural disorder on the transition between the two phases around its transition point. Our results show that a small deformation of the triangular structure changes dramatically the picture of the transition between two phases, removing in a considerable region the non-SOT in the system. This feature could explain the fact that the non-SOT is, up to now, not observed in experimental systems, and suggests a more advanced experimental setup to detect the non-SOT.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000359859400003 Publication Date 2015-08-21
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 3 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Odysseus and Methusalem programmes of the Flemish government. Computational resources were provided by HPC infrastructure of the University of Antwerp (CalcUA) a division of the Flemish Supercomputer Center (VSC). ; Approved Most recent IF: 3.836; 2015 IF: 3.736
Call Number UA @ lucian @ c:irua:127753 Serial (up) 4148
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Author Homm, P.; Dillemans, L.; Menghini, M.; Van Bilzen, B.; Bakalov, P.; Su, C.Y.; Lieten, R.; Houssa, M.; Nasr Esfahani, D.; Covaci, L.; Peeters, F.M.; Seo, J.W.; Locquet, J.P.;
Title Collapse of the low temperature insulating state in Cr-doped V2O3 thin films Type A1 Journal article
Year 2015 Publication Applied physics letters Abbreviated Journal Appl Phys Lett
Volume 107 Issue 107 Pages 111904
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We have grown epitaxial Cr-doped V2O3 thin films with Cr concentrations between 0% and 20% on (0001)-Al2O3 by oxygen-assisted molecular beam epitaxy. For the highly doped samples (>3%), a regular and monotonous increase of the resistance with decreasing temperature is measured. Strikingly, in the low doping samples (between 1% and 3%), a collapse of the insulating state is observed with a reduction of the low temperature resistivity by up to 5 orders of magnitude. A vacuum annealing at high temperature of the films recovers the low temperature insulating state for doping levels below 3% and increases the room temperature resistivity towards the values of Cr-doped V2O3 single crystals. It is well-know that oxygen excess stabilizes a metallic state in V2O3 single crystals. Hence, we propose that Cr doping promotes oxygen excess in our films during deposition, leading to the collapse of the low temperature insulating state at low Cr concentrations. These results suggest that slightly Cr-doped V2O3 films can be interesting candidates for field effect devices. (C) 2015 AIP Publishing LLC.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000361639200020 Publication Date 2015-09-19
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 ; The authors acknowledge financial support from the FWO Project No. G052010N10 as well as the EU-FP7 SITOGA Project. P.H. acknowledges support from Becas Chile-CONICYT. ; Approved Most recent IF: 3.411; 2015 IF: 3.302
Call Number UA @ lucian @ c:irua:128728 Serial (up) 4149
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Author Chinchilla, L.E.; Olmos, C.; Kurttepeli, M.; Bals, S.; Van Tendeloo, G.; Villa, A.; Prati, L.; Blanco, G.; Calvino, J.J.; Chen, X.; Hungría, A.B.
Title Combined macroscopic, nanoscopic, and atomic-scale characterization of gold-ruthenium bimetallic catalysts for octanol oxidation Type A1 Journal article
Year 2016 Publication Particle and particle systems characterization Abbreviated Journal Part Part Syst Char
Volume 33 Issue 33 Pages 419-437
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract A series of gold-ruthenium bimetallic catalysts of increasing Au:Ru molar ratios supported on a Ce0.62Zr0.38O2 mixed oxide are prepared and their structural and chemical features characterized by a combination of macroscopic and atomic-scale techniques based on scanning transmission electron microscopy. The influence of the temperature of the final reduction treatment used as activation step (350-700 degrees C range) is also investigated. The preparation method used allows catalysts to be successfully prepared where a major fraction of the metal nanoparticles is in the size range below 5 nm. The structural complexities characteristic of this type of catalysts are evidenced, as well as the capabilities and limitations of both the macroscopic and microscopic techniques in the characterization of the system of metal nanoparticles. A positive influence of the addition of Ru on both the resistance against sintering and the catalytic performance of the starting supported Au catalyst is evidenced.
Address
Corporate Author Thesis
Publisher Place of Publication Weinheim Editor
Language Wos 000379970000011 Publication Date 2016-05-24
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0934-0866 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.474 Times cited 7 Open Access OpenAccess
Notes ; This work was supported by the Ministry of Science and Innovation of Spain/ FEDER Program of the EU (Project Nos.: MAT 2013-40823-R and CSD2009-00013), ESTEEM2 (FP7-INFRASTUCTURE-2012-1-312493), Junta de Andalucia (FQM334 and FQM110 and Project: FQM3994). S.B. acknowledges the European Research Council, ERC grant No. 335078 – Colouratom. M.K. is grateful to the Fund for Scientific Research Flanders. X.C. thanks the Ramon y Cajal Program. ; ecas_sara Approved Most recent IF: 4.474
Call Number UA @ lucian @ c:irua:134958 Serial (up) 4150
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Author Agarwal, T.; Sorée, B.; Radu, I.; Raghavan, P.; Fiori, G.; Iannaccone, G.; Thean, A.; Heyns, M.; Dehaene, W.
Title Comparison of short-channel effects in monolayer MoS2 based junctionless and inversion-mode field-effect transistors Type A1 Journal article
Year 2016 Publication Applied physics letters Abbreviated Journal Appl Phys Lett
Volume 108 Issue 108 Pages 023506
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Conventional junctionless (JL) multi/gate (MuG) field-effect transistors (FETs) require extremely scaled channels to deliver high on-state current with low short-channel effect related leakage. In this letter, using ultra-thin 2D materials (e.g., monolayer MoS2), we present comparison of short-channel effects in JL, and inversion-mode (IM) FETs. We show that JL FETs exhibit better sub-threshold slope (S.S.) and drain-induced-barrier-lowering (DIBL) in comparison to IM FETs due to reduced peak electric field at the junctions. But, threshold voltage (VT) roll-off with channel length downscaling is found to be significantly higher in JL FETs than IM FETs, due to higher source/drain controlled charges (dE/dx) in the channel. Further, we show that although VT roll-off in JL FETs improves by increasing the gate control, i.e., by scaling the oxide, or channel thickness, the sensitivity of threshold voltage on structural parameters is found out to be high. (C) 2016 AIP Publishing LLC.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000370258400056 Publication Date 2016-01-16
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 13 Open Access
Notes ; ; Approved Most recent IF: 3.411
Call Number UA @ lucian @ c:irua:132318 Serial (up) 4152
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Author de de Meux, A.J.; Pourtois, G.; Genoe, J.; Heremans, P.
Title Comparison of the electronic structure of amorphous versus crystalline indium gallium zinc oxide semiconductor : structure, tail states and strain effects Type A1 Journal article
Year 2015 Publication Journal of physics: D: applied physics Abbreviated Journal J Phys D Appl Phys
Volume 48 Issue 48 Pages 435104
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract We study the evolution of the structural and electronic properties of crystalline indium gallium zinc oxide (IGZO) upon amorphization by first-principles calculation. The bottom of the conduction band (BCB) is found to be constituted of a pseudo-band of molecular orbitals that resonate at the same energy on different atomic sites. They display a bonding character between the s orbitals of the metal sites and an anti-bonding character arising from the interaction between the oxygen and metal s orbitals. The energy level of the BCB shifts upon breaking of the crystal symmetry during the amorphization process, which may be attributed to the reduction of the coordination of the cationic centers. The top of the valence band (TVB) is constructed from anti-bonding oxygen p orbitals. In the amorphous state, they have random orientation, in contrast to the crystalline state. This results in the appearance of localized tail states in the forbidden gap above the TVB. Zinc is found to play a predominant role in the generation of these tail states, while gallium hinders their formation. Last, we study the dependence of the fundamental gap and effective mass of IGZO on mechanical strain. The variation of the gap under strain arises from the enhancement of the anti-bonding interaction in the BCB due to the modification of the length of the oxygen-metal bonds and/or to a variation of the cation coordination. This effect is less pronounced for the amorphous material compared to the crystalline material, making amorphous IGZO a semiconductor of choice for flexible electronics. Finally, the effective mass is found to increase upon strain, in contrast to regular materials. This counterintuitive variation is due to the reduction of the electrostatic shielding of the cationic centers by oxygen, leading to an increase of the overlaps between the metal orbitals at the origin of the delocalization of the BCB. For the range of strain typically met in flexible electronics, the induced variation in the effective mass is found to be negligible (less than 1%).
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000365876300012 Publication Date 2015-09-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-3727 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.588 Times cited 23 Open Access
Notes Approved Most recent IF: 2.588; 2015 IF: 2.721
Call Number UA @ lucian @ c:irua:130277 Serial (up) 4153
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Author Sahin, H.; Torun, E.; Bacaksiz, C.; Horzum, S.; Kang, J.; Senger, R.T.; Peeters, F.M.
Title Computing optical properties of ultra-thin crystals Type A1 Journal article
Year 2016 Publication Wiley Interdisciplinary Reviews: Computational Molecular Science Abbreviated Journal Wires Comput Mol Sci
Volume 6 Issue 6 Pages 351-368
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract An overview is given of recent advances in experimental and theoretical understanding of optical properties of ultra-thin crystal structures (graphene, phosphorene, silicene, MoS2 , MoSe2, WS2, WSe2, h-AlN, h-BN, fluorographene, and graphane). Ultra-thin crystals are atomically thick-layered crystals that have unique properties which differ from their 3D counterpart. Because of the difficulties in the synthesis of few-atom-thick crystal structures, which are thought to be the main building blocks of future nanotechnology, reliable theoretical predictions of their electronic, vibrational, and optical properties are of great importance. Recent studies revealed the reliable predictive power of existing theoretical approaches based on density functional theory. (C) 2016 John Wiley & Sons, Ltd WIREs Comput Mol Sci 2016, 6:351-368. doi: 10.1002/wcms.1252 For further resources related to this article, please visit the .
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000379267300002 Publication Date 2016-02-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1759-0876 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 14.016 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. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H.S. is supported by a FWO Pegasus Long Marie Curie Fellowship. J.K. is supported by a FWO Pegasus short Marie Curie Fellowship. ; Approved Most recent IF: 14.016
Call Number UA @ lucian @ c:irua:134649 Serial (up) 4155
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Author Buh, J.; Kabanov, V.; Baranov, V.; Mrzel, A.; Kovic, A.; Mihailovic, D.
Title Control of switching between metastable superconducting states in delta-MoN nanowires Type A1 Journal article
Year 2015 Publication Nature communications Abbreviated Journal Nat Commun
Volume 6 Issue 6 Pages 10250
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract The superconducting state in one-dimensional nanosystems is very delicate. While fluctuations of the phase of the superconducting wave function lead to the spontaneous decay of persistent supercurrents in thin superconducting wires and nanocircuits, discrete phase-slip fluctuations can also lead to more exotic phenomena, such as the appearance of metastable superconducting states in current-bearing wires. Here we show that switching between different metastable superconducting states in d-MoN nanowires can be very effectively manipulated by introducing small amplitude electrical noise. Furthermore, we show that deterministic switching between metastable superconducting states with different numbers of phase-slip centres can be achieved in both directions with small electrical current pulse perturbations of appropriate polarity. The observed current-controlled bi-stability is in remarkable agreement with theoretically predicted trajectories of the system switching between different limit cycle solutions of a model one-dimensional superconductor.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000367576600002 Publication Date 2015-12-21
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 8 Open Access
Notes ; ; Approved Most recent IF: 12.124; 2015 IF: 11.470
Call Number UA @ lucian @ c:irua:131108 Serial (up) 4156
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Author Semkina, A.; Abakumov, M.; Grinenko, N.; Abakumov, A.; Skorikov, A.; Mironova, E.; Davydova, G.; Majouga, A.G.; Nukolova, N.; Kabanov, A.; Chekhonin, V.;
Title Core-shell-corona doxorubicin-loaded superparamagnetic Fe3O4 nanoparticles for cancer theranostics Type A1 Journal article
Year 2015 Publication Colloids and surfaces: B : biointerfaces Abbreviated Journal Colloid Surface B
Volume 136 Issue 136 Pages 1073-1080
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Superparamagnetic iron oxide magnetic nanoparticles (MNPs) are successfully used as contrast agents in magnetic-resonance imaging. They can be easily functionalized for drug delivery functions, demonstrating great potential for both imaging and therapeutic applications. Here we developed new pH-responsive theranostic core-shell-corona nanoparticles consisting of superparamagentic Fe3O4 core that displays high T2 relaxivity, bovine serum albumin (BSA) shell that binds anticancer drug, doxorubicin (Dox) and poly(ethylene glycol) (PEG) corona that increases stability and biocompatibility. The nanoparticles were produced by adsorption of the BSA shell onto the Fe3O4 core followed by crosslinking of the protein layer and subsequent grafting of the PEG corona using monoamino-terminated PEG via carbodiimide chemistry. The hydrodynamic diameter, zeta-potential, composition and T2 relaxivity of the resulting nanoparticles were characterized using transmission electron microscopy, dynamic light scattering, thermogravimetric analysis and T2-relaxometry. Nanoparticles were shown to absorb Dox molecules, possibly through a combination of electrostatic and hydrophobic interactions. The loading capacity (LC) of the nanoparticles was 8 wt.%. The Dox loaded nanoparticles release the drug at a higher rate at pH 5.5 compared to pH 7.4 and display similar cytotoxicity against C6 and HEK293 cells as the free Dox. (C) 2015 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000367408100131 Publication Date 2015-11-10
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0927-7765 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.887 Times cited 37 Open Access
Notes Approved Most recent IF: 3.887; 2015 IF: 4.152
Call Number UA @ lucian @ c:irua:131075 Serial (up) 4157
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