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Author Antipov, E.V.; Khasanova, N.R.; Pshirkov, J.S.; Putilin, S.N.; Bougerol, C.; Lebedev, O.I.; Van Tendeloo, G.; Baranov, A.N.; Park, Y.W.
Title The superconducting bismuth-based mixed oxides Type A1 Journal article
Year 2002 Publication Current applied physics T2 – QTSM and QFS 02 Symposium, MAY 08-10, 2002, SEOUL, SOUTH KOREA Abbreviated Journal Curr Appl Phys
Volume (up) 2 Issue 5 Pages 425-430
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The present paper describes the synthesis, characterization of mixed-valence bismuthates with three- or two-dimensional perovskite-like structures and structural criteria that influence superconductivity in these compounds. Single-phase samples of Sr1-xKxBiO3 were prepared for the broad range of K-content: 0.25 less than or equal to x less than or equal to 0.65. For these bismuthates the symmetry of the structure changes from monoclinic to orthorhombic and finally to tetragonal upon increasing the K-content thus resulting in the decrease of the Bi-O distances and reduction of the network distortions. Superconductivity with maximum T-c = 12 K exists in the narrow range (x approximate to 0.5-0.6) within the stability field of the tetragonal phase (0.33 less than or equal to x less than or equal to 0.65), when the three-dimensional octahedral framework has close to the ideal perovskite structure arrangement. The layered type (Ba,K)(3)Bi2O7 and (Ba,K)(2)BiO4 bismuthates belonging to the A(n+1)B(n)O(3n+1) homologous series were investigated. Buckling of the (BiO2) layers in the structure of the n = 2 member occurs due to the ordering of alkaline- and alkaline-earth cations between two independent positions. The formation of the one-layer bismuthate was revealed by Electron Microscopy and XRPD studies. Both types of compounds are considered to be possible candidates for new superconducting materials among bismuthates. (C) 2002 Published by Elsevier Science B.V.
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Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000179330900015 Publication Date 2002-11-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1567-1739; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.971 Times cited 2 Open Access
Notes Approved Most recent IF: 1.971; 2002 IF: NA
Call Number UA @ lucian @ c:irua:103336 Serial 3598
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Author Zhang, H.; Gauquelin, N.; McMahon, C.; Hawthorn, D.G.; Botton, G.A.; Wei, J.Y.T.
Title Synthesis of high-oxidation Y-Ba-Cu-O phases in superoxygenated thin films Type A1 Journal article
Year 2018 Publication Physical review materials Abbreviated Journal
Volume (up) 2 Issue 3 Pages 033803
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract It is known that solid-state reaction in high-pressure oxygen can stabilize high-oxidation phases of Y-Ba-Cu-O superconductors in powder form. We extend this superoxygenation concept of synthesis to thin films which, due to their large surface-to-volume ratio, are more reactive thermodynamically. Epitaxial thin films of YBa2Cu3O7-delta grown by pulsed laser deposition are annealed at up to 700 atm O-2 and 900 degrees C, in conjunction with Cu enrichment by solid-state diffusion. The films show the clear formation of Y2Ba4Cu7O15-delta and Y2Ba4Cu8O16 as well as regions of YBa2Cu5O9-delta and YBa2Cu6O10-delta phases, according to scanning transmission electron microscopy, x-ray diffraction, and x-ray absorption spectroscopy. Similarly annealed YBa2Cu3O7-delta powders show no phase conversion. Our results demonstrate a route of synthesis towards discovering more complex phases of cuprates and other superconducting oxides.
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Publisher American Physical Society Place of Publication College Park, Md Editor
Language Wos 000428244900004 Publication Date 2018-03-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2475-9953 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 2 Open Access Not_Open_Access
Notes ; This work is supported by NSERC, CFI-OIT, and CIFAR. The electron microscopy work was carried out at the Canadian Centre for Electron Microscopy, a National Facility supported by the Canada Foundation for Innovation under the Major Science Initiative program, McMaster University, and NSERC. The XAS work was performed at the Canadian Light Source, which is supported by NSERC, NRC, CIHR, and the University of Saskatchewan. ; Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:150829 Serial 4982
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Author Groenendijk, D.J.; Autieri, C.; van Thiel, T.C.; Brzezicki, W.; Hortensius, J.R.; Afanasiev, D.; Gauquelin, N.; Barone, P.; van den Bos, K.H.W.; van Aert, S.; Verbeeck, J.; Filippetti, A.; Picozzi, S.; Cuoco, M.; Caviglia, A.D.
Title Berry phase engineering at oxide interfaces Type A1 Journal article
Year 2020 Publication Abbreviated Journal Phys. Rev. Research
Volume (up) 2 Issue 2 Pages 023404
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Three-dimensional strontium ruthenate (SrRuO3) is an itinerant ferromagnet that features Weyl points acting as sources of emergent magnetic fields, anomalous Hall conductivity, and unconventional spin dynamics. Integrating SrRuO3 in oxide heterostructures is potentially a novel route to engineer emergent electrodynamics, but its electronic band topology in the two-dimensional limit remains unknown. Here we show that ultrathin SrRuO3 exhibits spin-polarized topologically nontrivial bands at the Fermi energy. Their band anticrossings show an enhanced Berry curvature and act as competing sources of emergent magnetic fields. We control their balance by designing heterostructures with symmetric (SrTiO3/SrRuO3/SrTiO3 and SrIrO3/SrRuO3/SrIrO3) and asymmetric interfaces (SrTiO3/SrRuO3/SrIrO3). Symmetric structures exhibit an interface-tunable single-channel anomalous Hall effect, while ultrathin SrRuO3 embedded in asymmetric structures shows humplike features consistent with multiple Hall contributions. The band topology of two-dimensional SrRuO3 proposed here naturally accounts for these observations and harmonizes a large body of experimental results.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000603642700008 Publication Date 2020-06-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2643-1564 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 58 Open Access OpenAccess
Notes Nederlandse Organisatie voor Wetenschappelijk Onderzoek; Fonds Wetenschappelijk Onderzoek; European Research Council; Horizon 2020, 677458 770887 731473 ; Fondazione Cariplo, 2013-0726 ; Narodowe Centrum Nauki, 2016/23/B/ST3/00839 ; Fundacja na rzecz Nauki Polskiej; Universiteit Antwerpen; Vlaamse regering; Approved Most recent IF: NA
Call Number EMAT @ emat @c:irua:172462 Serial 6401
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Author Wu, S.; Luo, X.; Turner, S.; Peng, H.; Lin, W.; Ding, J.; David, A.; Wang, B.; Van Tendeloo, G.; Wang, J.; Wu, T.;
Title Nonvolatile resistive switching in Pt/LaAlO3/SrTiO3 heterostructures Type A1 Journal article
Year 2013 Publication Physical review X Abbreviated Journal Phys Rev X
Volume (up) 3 Issue 4 Pages 041027-14
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Resistive switching heterojunctions, which are promising for nonvolatile memory applications, usually share a capacitorlike metal-oxide-metal configuration. Here, we report on the nonvolatile resistive switching in Pt/LaAlO3/SrTiO3 heterostructures, where the conducting layer near the LaAlO3/SrTiO3 interface serves as the unconventional bottom electrode although both oxides are band insulators. Interestingly, the switching between low-resistance and high-resistance states is accompanied by reversible transitions between tunneling and Ohmic characteristics in the current transport perpendicular to the planes of the heterojunctions. We propose that the observed resistive switching is likely caused by the electric-field-induced drift of charged oxygen vacancies across the LaAlO3/SrTiO3 interface and the creation of defect-induced gap states within the ultrathin LaAlO3 layer. These metal-oxide-oxide heterojunctions with atomically smooth interfaces and defect-controlled transport provide a platform for the development of nonvolatile oxide nanoelectronics that integrate logic and memory devices.
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Corporate Author Thesis
Publisher Place of Publication College Park, Md Editor
Language Wos 000328862400001 Publication Date 2013-12-17
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2160-3308; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 12.789 Times cited 77 Open Access
Notes FWO;FP7;IFOX; Countatoms; Hercules Approved Most recent IF: 12.789; 2013 IF: 8.463
Call Number UA @ lucian @ c:irua:112524 Serial 2365
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Author Shuhui Sun, Gaixia Zhang, Nicolas Gauquelin, Ning Chen, Jigang Zhou, Songlan Yang, Weifeng Chen, Xiangbo Meng, Dongsheng Geng, Mohammad N. Banis, Ruying Li, Siyu Ye, Shanna Knights, Gianluigi A. Botton, Tsun-Kong Sham & Xueliang Sun
Title Single-atom Catalysis Using Pt/Graphene Achieved through Atomic Layer Deposition Type A1 Journal Article
Year 2013 Publication Scientific Reports Abbreviated Journal
Volume (up) 3 Issue Pages 1775
Keywords A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ;
Abstract Platinum-nanoparticle-based catalysts are widely used in many important chemical processes and

automobile industries. Downsizing catalyst nanoparticles to single atoms is highly desirable to maximize

their use efficiency, however, very challenging. Here we report a practical synthesis for isolated single Pt

atoms anchored to graphene nanosheet using the atomic layer deposition (ALD) technique. ALD offers the

capability of precise control of catalyst size span from single atom, subnanometer cluster to nanoparticle.

The single-atom catalysts exhibit significantly improved catalytic activity (up to 10 times) over that of the

state-of-the-art commercial Pt/C catalyst. X-ray absorption fine structure (XAFS) analyses reveal that the

low-coordination and partially unoccupied densities of states of 5d orbital of Pt atoms are responsible for the

excellent performance. This work is anticipated to form the basis for the exploration of a next generation of

highly efficient single-atom catalysts for various applications.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000318334300004 Publication Date 2013-05-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Additional Links
Impact Factor Times cited 345 Open Access
Notes Approved Most recent IF: NA
Call Number EMAT @ emat @ Serial 4543
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Author Yin, C.; Krishnan, D.; Gauquelin, N.; Verbeeck, J.; Aarts, J.
Title Controlling the interfacial conductance in LaAlO3/SrTiO3 in 90 degrees off-axis sputter deposition Type A1 Journal article
Year 2019 Publication Physical review materials Abbreviated Journal
Volume (up) 3 Issue 3 Pages 034002
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We report on the fabrication of conducting interfaces between LaAlO3 and SrTiO3 by 90 degrees off-axis sputtering in an Ar atmosphere. At a growth pressure of 0.04 mbar the interface is metallic, with a carrier density of the order of 1 x 10(13) cm(-2) at 3 K. By increasing the growth pressure, we observe an increase of the out-of-plane lattice constants of the LaAlO3 films while the in-plane lattice constants do not change. Also, the low-temperature sheet resistance increases with increasing growth pressure, leading to an insulating interface when the growth pressure reaches 0.10 mbar. We attribute the structural variations to an increase of the La/Al ratio, which also explains the transition from metallic behavior to insulating behavior of the interfaces. Our research shows that the control which is furnished by the Ar pressure makes sputtering as versatile a process as pulsed laser deposition, and emphasizes the key role of the cation stoichiometry of LaAlO3 in the formation of the conducting interface.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000461077100002 Publication Date 2019-03-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2475-9953 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.926 Times cited 4 Open Access Not_Open_Access
Notes ; We thank Nikita Lebedev, Aymen Ben Hamida, and Prateek Kumar for useful discussions and Giordano Mattoni, Jun Wang, Vincent Joly, and Hozanna Miro for their technical assistance. We also thank Jean-Marc Triscone and his group for sharing their design of the sputtering system with us. This work is part of the FOM research programme DESCO with Project No. 149, which is (partly) financed by the Netherlands Organisation for Scientific Research (NWO). C.Y. is supported by China Scholarship Council (CSC) with Grant No. 201508110214. N.G., D.K., and J.V. acknowledge financial support from the GOA project “Solarpaint” of the University of Antwerp. ; Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:158547 Serial 5243
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Author Lin, S.-H.; Milošević, M.V.; Covaci, L.; Janko, B.; Peeters, F.M.
Title Quantum rotor in nanostructured superconductors Type A1 Journal article
Year 2014 Publication Scientific reports Abbreviated Journal Sci Rep-Uk
Volume (up) 4 Issue Pages 4542-4546
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract Despite its apparent simplicity, the idealized model of a particle constrained to move on a circle has intriguing dynamic properties and immediate experimental relevance. While a rotor is rather easy to set up classically, the quantum regime is harder to realize and investigate. Here we demonstrate that the quantum dynamics of quasiparticles in certain classes of nanostructured superconductors can be mapped onto a quantum rotor. Furthermore, we provide a straightforward experimental procedure to convert this nanoscale superconducting rotor into a regular or inverted quantum pendulum with tunable gravitational field, inertia, and drive. We detail how these novel states can be detected via scanning tunneling spectroscopy. The proposed experiments will provide insights into quantum dynamics and quantum chaos.
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Corporate Author Thesis
Publisher Nature Publishing Group Place of Publication London Editor
Language Wos 000333555300007 Publication Date 2014-04-01
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 4 Open Access
Notes ; The work was supported by the Flemish Science Foundation (FWO-Vl), the U. S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under contract W-31-109-Eng-38, and the US National Science Foundation via NSF-NIRT ECS-0609249. ; Approved Most recent IF: 4.259; 2014 IF: 5.578
Call Number UA @ lucian @ c:irua:116848 Serial 2785
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Author Neubert, S.; Mitoraj, D.; Shevlin, S.A.; Pulisova, P.; Heimann, M.; Du, Y.; Goh, G.K.L.; Pacia, M.; Kruczała, K.; Turner, S.; Macyk, W.; Guo, Z.X.; Hocking, R.K.; Beranek, R.;
Title Highly efficient rutile TiO2 photocatalysts with single Cu(II) and Fe(III) surface catalytic sites Type A1 Journal article
Year 2016 Publication Journal of materials chemistry A : materials for energy and sustainability Abbreviated Journal J Mater Chem A
Volume (up) 4 Issue 4 Pages 3127-3138
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Highly active photocatalysts were obtained by impregnation of nanocrystalline rutile TiO2 powders with small amounts of Cu(II) and Fe(III) ions, resulting in the enhancement of initial rates of photocatalytic degradation of 4-chlorophenol in water by factors of 7 and 4, compared to pristine rutile, respectively. Detailed structural analysis by EPR and X-ray absorption spectroscopy (EXAFS) revealed that Cu(II) and Fe(III) are present as single species on the rutile surface. The mechanism of the photoactivity enhancement was elucidated by a combination of DFT calculations and detailed experimental mechanistic studies including photoluminescence measurements, photocatalytic experiments using scavengers, OH radical detection, and photopotential transient measurements. The results demonstrate that the single Cu(II) and Fe(III) ions act as effective cocatalytic sites, enhancing the charge separation, catalyzing “dark” redox reactions at the interface, thus improving the normally very low quantum yields of UV light-activated TiO2 photocatalysts. The exact mechanism of the photoactivity enhancement differs depending on the nature of the cocatalyst. Cu(II)-decorated samples exhibit fast transfer of photogenerated electrons to Cu(II/I) sites, followed by enhanced catalysis of dioxygen reduction, resulting in improved charge separation and higher photocatalytic degradation rates. At Fe(III)-modified rutile the rate of dioxygen reduction is not improved and the photocatalytic enhancement is attributed to higher production of highly oxidizing hydroxyl radicals produced by alternative oxygen reduction pathways opened by the presence of catalytic Fe(III/II) sites. Importantly, it was demonstrated that excessive heat treatment (at 450 degrees C) of photocatalysts leads to loss of activity due to migration of Cu(II) and Fe(III) ions from TiO2 surface to the bulk, accompanied by formation of oxygen vacancies. The demonstrated variety of mechanisms of photoactivity enhancement at single site catalyst-modified photocatalysts holds promise for developing further tailored photocatalysts for various applications.
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Corporate Author Thesis
Publisher Place of Publication Cambridge Editor
Language Wos 000371077300040 Publication Date 2015-12-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2050-7488; 2050-7496 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 8.867 Times cited 44 Open Access
Notes Approved Most recent IF: 8.867
Call Number UA @ lucian @ c:irua:132322 Serial 4191
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Author Chen, B.; Gauquelin, N.; Reith, P.; Halisdemir, U.; Jannis, D.; Spreitzer, M.; Huijben, M.; Abel, S.; Fompeyrine, J.; Verbeeck, J.; Hilgenkamp, H.; Rijnders, G.; Koster, G.
Title Thermal-strain-engineered ferromagnetism of LaMnO3/SrTiO3 heterostructures grown on silicon Type A1 Journal article
Year 2020 Publication Physical review materials Abbreviated Journal Phys. Rev. Materials
Volume (up) 4 Issue 2 Pages 024406
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The integration of oxides on Si remains challenging, which largely hampers the practical applications of oxide-based electronic devices with superior performance. Recently, LaMnO3/SrTiO3 (LMO/STO) heterostructures have gained renewed interest for the debating origin of the ferromagnetic-insulating ground state as well as for their spin-filter applications. Here we report on the structural and magnetic properties of high-quality LMO/STO heterostructures grown on silicon. The chemical abruptness across the interface was investigated by atomic-resolution scanning transmission electron microscopy. The difference in the thermal expansion coefficients between LMO and Si imposed a large biaxial tensile strain to the LMO film, resulting in a tetragonal structure with c/a∼ 0.983. Consequently, we observed a significantly suppressed ferromagnetism along with an enhanced coercive field, as compared to the less distorted LMO film (c/a∼1.004) grown on STO single crystal. The results are discussed in terms of tensile-strain enhanced antiferromagnetic instabilities. Moreover, the ferromagnetism of LMO on Si sharply disappeared below a thickness of 5 unit cells, in agreement with the LMO/STO case, pointing to a robust critical behavior irrespective of the strain state. Our results demonstrate that the growth of oxide films on Si can be a promising way to study the tensile-strain effects in correlated oxides, and also pave the way towards the integration of multifunctional oxides on Si with atomic-layer control.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000513552900003 Publication Date 2020-02-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2475-9953 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.4 Times cited 6 Open Access Not_Open_Access
Notes Nederlandse Organisatie voor Wetenschappelijk Onderzoek; Universiteit Antwerpen; Vlaamse regering; Fonds Wetenschappelijk Onderzoek, G093417N ; Javna Agencija za Raziskovalno Dejavnost RS, J2-9237 P2-0091 ; European Commission, H2020-ICT-2016-1-732642 ; Approved Most recent IF: 3.4; 2020 IF: NA
Call Number EMAT @ emat @c:irua:167782 Serial 6375
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Author Araizi-Kanoutas, G.; Geessinck, J.; Gauquelin, N.; Smit, S.; Verbeek, X.H.; Mishra, S.K.; Bencok, P.; Schlueter, C.; Lee, T.-L.; Krishnan, D.; Fatermans, J.; Verbeeck, J.; Rijnders, G.; Koster, G.; Golden, M.S.
Title Co valence transformation in isopolar LaCoO3/LaTiO3 perovskite heterostructures via interfacial engineering Type A1 Journal article
Year 2020 Publication Physical review materials Abbreviated Journal Phys. Rev. Materials
Volume (up) 4 Issue 2 Pages 026001
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We report charge transfer up to a single electron per interfacial unit cell across nonpolar heterointerfaces from the Mott insulator LaTiO3 to the charge transfer insulator LaCoO3. In high-quality bi- and trilayer systems grown using pulsed laser deposition, soft x-ray absorption, dichroism, and scanning transmission electron microscopy-electron energy loss spectroscopy are used to probe the cobalt-3d electron count and provide an element-specific investigation of the magnetic properties. The experiments show the cobalt valence conversion is active within 3 unit cells of the heterointerface, and able to generate full conversion to 3d7 divalent Co, which displays a paramagnetic ground state. The number of LaTiO3/LaCoO3 interfaces, the thickness of an additional, electronically insulating “break” layer between the LaTiO3 and LaCoO3, and the LaCoO3 film thickness itself in trilayers provide a trio of control knobs for average charge of the cobalt ions in LaCoO3, illustrating the efficacy of O−2p band alignment as a guiding principle for property design in complex oxide heterointerfaces.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000513551200007 Publication Date 2020-02-10
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2475-9953 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.4 Times cited 13 Open Access OpenAccess
Notes Nederlandse Organisatie voor Wetenschappelijk Onderzoek; Universiteit Antwerpen; Horizon 2020, 730872 ; Department of Science and Technology, Ministry of Science and Technology, SR/NM/Z-07/2015 ; Jawaharlal Nehru Centre for Advanced Scientific Research; Approved Most recent IF: 3.4; 2020 IF: NA
Call Number EMAT @ emat @c:irua:167787 Serial 6376
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Author Lin, S.-C.; Kuo, C.-T.; Shao, Y.-C.; Chuang, Y.-D.; Geessinck, J.; Huijben, M.; Rueff, J.-P.; Graff, I.L.; Conti, G.; Peng, Y.; Bostwick, A.; Gullikson, E.; Nemsak, S.; Vailionis, A.; Gauquelin, N.; Verbeeck, J.; Ghiringhelli, G.; Schneider, C.M.; Fadley, C.S.
Title Two-dimensional electron systems in perovskite oxide heterostructures : role of the polarity-induced substitutional defects Type A1 Journal article
Year 2020 Publication Physical review materials Abbreviated Journal
Volume (up) 4 Issue 11 Pages 115002
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The discovery of a two-dimensional electron system (2DES) at the interfaces of perovskite oxides such as LaAlO3 and SrTiO3 has motivated enormous efforts in engineering interfacial functionalities with this type of oxide heterostructures. However, the fundamental origins of the 2DES are still not understood, e.g., the microscopic mechanisms of coexisting interface conductivity and magnetism. Here we report a comprehensive spectroscopic investigation on the depth profile of 2DES-relevant Ti 3d interface carriers using depthand element-specific techniques like standing-wave excited photoemission and resonant inelastic scattering. We found that one type of Ti 3d interface carriers, which give rise to the 2DES are located within three unit cells from the n-type interface in the SrTiO3 layer. Unexpectedly, another type of interface carriers, which are polarity-induced Ti-on-Al antisite defects, reside in the first three unit cells of the opposing LaAlO3 layer (similar to 10 angstrom). Our findings provide a microscopic picture of how the localized and mobile Ti 3d interface carriers distribute across the interface and suggest that the 2DES and 2D magnetism at the LaAlO3/SrTiO3 interface have disparate explanations as originating from different types of interface carriers.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000592432200004 Publication Date 2020-11-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2475-9953 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.4 Times cited 7 Open Access OpenAccess
Notes ; We thank G. M. De Luca and L. Braicovich for discussions. Charles S. Fadley was deceased on August 1, 2019. We are grateful for his significant contributions to this work. We thank Advanced Light Source for the access to Beamline 8.0.3 (qRIXS) via Proposal No. 09892 and beamline 7.0.2 (MAESTRO) via Proposal No. RA-00291 that contributed to the results presented here. We thank synchrotron SOLEIL (via Proposal No. 99180118) for the access to Beamline GALAXIES. This work was supported by the U.S. Department of Energy (DOE) under Contract No. DE-AC02-05CH11231 (Advanced Light Source), and by DOE Contract No. DE-SC0014697 through the University of California, Davis (S.-C.L., C.-T.K, and C.S.F.), and from the Julich Research Center, Peter Grunberg Institute, PGI-6. I. L. G. wishes to thank Brazilian scientific agencies CNPQ (Project No. 200789/2017-1) and CAPES (CAPES-PrInt-UFPR) for their financial support. J.V. and N.G. acknowledge funding from the Geconcentreerde Onderzoekacties (GOA) project “Solarpaint” of the University of Antwerp and the European Union's horizon 2020 research and innovation program ES-TEEM3 under grant agreement no 823717. The Qu-Ant-EM microscope used in this study was partly funded by the Hercules fund from the Flemish Government. ; esteem3TA; esteem3reported Approved Most recent IF: 3.4; 2020 IF: NA
Call Number UA @ admin @ c:irua:174316 Serial 6713
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Author Herzog, M.J.; Gauquelin, N.; Esken, D.; Verbeeck, J.; Janek, J.
Title Increased Performance Improvement of Lithium-Ion Batteries by Dry Powder Coating of High-Nickel NMC with Nanostructured Fumed Ternary Lithium Metal Oxides Type A1 Journal article
Year 2021 Publication ACS applied energy materials Abbreviated Journal ACS Appl. Energy Mater.
Volume (up) 4 Issue 9 Pages 8832-8848
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Dry powder coating is an effective approach to protect the surfaces of layered cathode active materials (CAMs) in lithium-ion batteries. Previous investigations indicate an incorporation of lithium ions in fumed Al2O3, ZrO2, and TiO2 coatings on LiNi0.7Mn0.15Co0.15O2 during cycling, improving the cycling performance. Here, this coating approach is transferred for the first time to fumed ternary LiAlO2, Li4Zr3O8, and Li4Ti5O12 and directly compared with their lithium-free equivalents. All materials could be processed equally and their nanostructured small aggregates accumulate on the CAM surfaces to quite homogeneous coating layers with a certain porosity. The LiNixMnyCozO2 (NMC) coated with lithium-containing materials shows an enhanced improvement in overall capacity, capacity retention, rate performance, and polarization behavior during cycling, compared to their lithium-free analogues. The highest rate performance was achieved with the fumed ZrO2 coating, while the best long-term cycling stability with the highest absolute capacity was obtained for the fumed LiAlO2-coated NMC. The optimal coating agent for NMC to achieve a balanced system is fumed Li4Ti5O12, providing a good compromise between high rate capability and good capacity retention. The coating agents prevent CAM particle cracking and degradation in the order LiAlO2 ≈ Al2O3 > Li4Ti5O12 > Li4Zr3O8 > ZrO2 > TiO2. A schematic model for the protection and electrochemical performance enhancement of high-nickel NMC with fumed metal oxide coatings is sketched. It becomes apparent that physical and chemical characteristics of the coating significantly influence the performance of NMC. A high degree of coating-layer porosity is favorable for the rate capability, while a high coverage of the surface, especially in vulnerable grain boundaries, enhances the long-term cycling stability and improves the cracking behavior of NMCs. While zirconium-containing coatings possess the best chemical properties for high rate performances, aluminum-containing coatings feature a superior chemical nature to protect high-nickel NMCs.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000703338600018 Publication Date 2021-09-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2574-0962 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 15 Open Access OpenAccess
Notes For his support in scanning electron microscopy analysis, the authors thank Erik Peldszus. N. G. and J. V. acknowledge funding from GOA project “Solarpaint” of the University of Antwerp and from the Flemish Research Fund (FWO) project G0F1320N. The Qu-Ant-EM microscope and the direct electron detector were partly funded by the Hercules fund from the Flemish Government Approved Most recent IF: NA
Call Number EMAT @ emat @c:irua:183949 Serial 6823
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Author Poulain, R.; Lumbeeck, G.; Hunka, J.; Proost, J.; Savolainen, H.; Idrissi, H.; Schryvers, D.; Gauquelin, N.; Klein, A.
Title Electronic and chemical properties of nickel oxide thin films and the intrinsic defects compensation mechanism Type A1 Journal article
Year 2022 Publication ACS applied electronic materials Abbreviated Journal
Volume (up) 4 Issue 6 Pages 2718-2728
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Although largely studied, contradictory results on nickel oxide (NiO) properties can be found in the literature. We herein propose a comprehensive study that aims at leveling contradictions related to NiO materials with a focus on its conductivity, surface properties, and the intrinsic charge defects compensation mechanism with regards to the conditions preparation. The experiments were performed by in situ photo-electron spectroscopy, electron energy loss spectroscopy, and optical as well as electrical measurements on polycrystalline NiO thin films prepared under various preparation conditions by reactive sputtering. The results show that surface and bulk properties were strongly related to the deposition temperature with in particular the observation of Fermi level pinning, high work function, and unstable oxygen-rich grain boundaries for the thin films produced at room temperature but not at high temperature (>200 degrees C). Finally, this study provides substantial information about surface and bulk NiO properties enabling to unveil the origin of the high electrical conductivity of room temperature NiO thin films and also for supporting a general electronic charge compensation mechanism of intrinsic defects according to the deposition temperature.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000819431200001 Publication Date 2022-06-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2637-6113 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access Not_Open_Access
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:189555 Serial 7081
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Author Birkholzer, Y.A.; Sotthewes, K.; Gauquelin, N.; Riekehr, L.; Jannis, D.; van der Minne, E.; Bu, Y.; Verbeeck, J.; Zandvliet, H.J.W.; Koster, G.; Rijnders, G.
Title High-strain-induced local modification of the electronic properties of VO₂ thin films Type A1 Journal article
Year 2022 Publication ACS applied electronic materials Abbreviated Journal
Volume (up) 4 Issue 12 Pages 6020-6028
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Vanadium dioxide (VO2) is a popular candidate for electronic and optical switching applications due to its well-known semiconductor-metal transition. Its study is notoriously challenging due to the interplay of long- and short-range elastic distortions, as well as the symmetry change and the electronic structure changes. The inherent coupling of lattice and electronic degrees of freedom opens the avenue toward mechanical actuation of single domains. In this work, we show that we can manipulate and monitor the reversible semiconductor-to-metal transition of VO2 while applying a controlled amount of mechanical pressure by a nanosized metallic probe using an atomic force microscope. At a critical pressure, we can reversibly actuate the phase transition with a large modulation of the conductivity. Direct tunneling through the VO2-metal contact is observed as the main charge carrier injection mechanism before and after the phase transition of VO2. The tunneling barrier is formed by a very thin but persistently insulating surface layer of the VO2. The necessary pressure to induce the transition decreases with temperature. In addition, we measured the phase coexistence line in a hitherto unexplored regime. Our study provides valuable information on pressure-induced electronic modifications of the VO2 properties, as well as on nanoscale metal-oxide contacts, which can help in the future design of oxide electronics.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000890974900001 Publication Date 2022-11-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2637-6113 ISBN Additional Links UA library record; WoS full record
Impact Factor Times cited 2 Open Access OpenAccess
Notes This work received financial support from the project Green ICT (grant number 400.17.607) of the research program NWA, which is financed by the Dutch Research Council (NWO), Research Foundation Flanders (FWO grant number G0F1320N), and the European Union’s Horizon 2020 research and innovation program within a contract for Integrating Activities for Advanced Communities (grant number 823717 − ESTEEM3). The K2 camera was funded through the Research Foundation Flanders (FWO-Hercules grant number G0H4316N – “Direct electron detector for soft matter TEM”).; esteem3reported; esteem3jra Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:192712 Serial 7309
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Author Lin, F.; Meng; Kukueva, E.; Mertens, M.; Van Doorslaer, S.; Bals, S.; Cool, P.
Title New insights into the mesophase transformation of ethane-bridged PMOs by the influence of different counterions under basic conditions Type A1 Journal article
Year 2015 Publication RSC advances Abbreviated Journal Rsc Adv
Volume (up) 5 Issue 5 Pages 5553-5562
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA)
Abstract The counterions are of crucial importance in determining the mesostructure and morphology of ethanebridged PMO materials synthesized under basic conditions. By using CTABr as the surfactant, the final PMO materials show a 2-D hexagonal (p6mm) mesophase, while PMO materials with cubic (Pm (3) over barn ) mesostructure are obtained when CTACl or CTA(SO4)(1)/(2) are used. With gradually replacing CTABr by CTACl or CTA(SO4) (1)/(2) while keeping the total surfactant concentration constant, a clear p6mm to Pm (3) over barn 3n mesophase evolution process is observed. For a given gel composition, the mesophase of ethanebridged PMO materials can also be adjusted by the addition of different sodium salts. In short, the effect of the counterions on the mesophase can be attributed to the binding strength of the ions on the surfactant micelles, which follows the Hofmeister series (SO42- < Cl- < Br-< NO3- < SCN-). Furthermore, it is found that the hydrolysis and condensation rate of the organosilica precursor also plays an important role in the formation of the final mesostructure
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000347304900010 Publication Date 2014-12-11
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2046-2069; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.108 Times cited 6 Open Access Not_Open_Access
Notes ; The Erasmus Mundus CONNEC program is acknowledged for PhD funding of F. L. Furthermore, the authors acknowledge support by the GOA-BOF project 'Optimization of the structureactivity relation in nanoporous materials', funded by the University of Antwerp. ; Approved Most recent IF: 3.108; 2015 IF: 3.840
Call Number c:irua:123768 Serial 2317
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Author Mordvinova, N.; Emelin, P.; Vinokurov, A.; Dorofeev, S.; Abakumov, A.; Kuznetsova, T.
Title Surface processes during purification of InP quantum dots Type A1 Journal article
Year 2014 Publication Beilstein journal of nanotechnology Abbreviated Journal Beilstein J Nanotech
Volume (up) 5 Issue Pages 1220-1225
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Recently, a new simple and fast method for the synthesis of InP quantum dots by using phosphine as phosphorous precursor and myristic acid as surface stabilizer was reported. Purification after synthesis is necessary to obtain samples with good optical properties. Two methods of purification were compared and the surface processes which occur during purification were studied. Traditional precipitation with acetone is accompanied by a small increase in photoluminescence. It occurs that during the purification the hydrolysis of the indium precursor takes place, which leads to a better surface passivation. The electrophoretic purification technique does not increase luminescence efficiency but yields very pure quantum dots in only a few minutes. Additionally, the formation of In(OH)(3) during the low temperature synthesis was explained. Purification of quantum dots is a very significant part of post-synthetical treatment that determines the properties of the material. But this subject is not sufficiently discussed in the literature. The paper is devoted to the processes that occur at the surface of quantum dots during purification. A new method of purification, electrophoresis, is investigated and described in particular.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000339912400002 Publication Date 2014-08-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2190-4286; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.127 Times cited 5 Open Access
Notes Approved Most recent IF: 3.127; 2014 IF: 2.670
Call Number UA @ lucian @ c:irua:118748 Serial 3397
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Author N. Gauquelin, D. G. Hawthorn, G. A. Sawatzky, R. X. Liang, D. A. Bonn, W. N. Hardy & G.A. Botton
Title Atomic scale real-space mapping of holes in YBa2Cu3O6+δ Type A1 Journal Article
Year 2014 Publication Nature Communications Abbreviated Journal
Volume (up) 5 Issue Pages 4275
Keywords A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ;
Abstract The high-temperature superconductor YBa2Cu3O6+δ consists of two main structural units—a bilayer of CuO2 planes that are central to superconductivity and a CuO2+δ chain layer. Although the functional role of the planes and chains has long been established, most probes integrate over both, which makes it difficult to distinguish the contribution of each. Here we use electron energy loss spectroscopy to directly resolve the plane and chain contributions to the electronic structure in YBa2Cu3O6 and YBa2Cu3O7. We directly probe the charge transfer of holes from the chains to the planes as a function of oxygen content, and show that the change in orbital occupation of Cu is large in the chain layer but modest in CuO2 planes, with holes in the planes doped primarily into the O 2p states. These results provide direct insight into the local electronic structure and charge transfers in this important high-temperature superconductor.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000340615100002 Publication Date 2014-07-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Additional Links
Impact Factor Times cited 22 Open Access
Notes Approved Most recent IF: NA
Call Number EMAT @ emat @ Serial 4542
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Author Li, L.; Liao, Z.; Gauquelin, N.; Minh Duc Nguyen; Hueting, R.J.E.; Gravesteijn, D.J.; Lobato, I.; Houwman, E.P.; Lazar, S.; Verbeeck, J.; Koster, G.; Rijnders, G.
Title Epitaxial stress-free growth of high crystallinity ferroelectric PbZr0.52Ti0.48O3 on GaN/AlGaN/Si(111) substrate Type A1 Journal article
Year 2018 Publication Advanced Materials Interfaces Abbreviated Journal Adv Mater Interfaces
Volume (up) 5 Issue 2 Pages 1700921
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract <script type='text/javascript'>document.write(unpmarked('Due to its physical properties gallium-nitride (GaN) is gaining a lot of attention as an emerging semiconductor material in the field of high-power and high-frequency electronics applications. Therefore, the improvement in the performance and/or perhaps even extension in functionality of GaN based devices would be highly desirable. The integration of ferroelectric materials such as lead-zirconate-titanate (PbZrxTi1-xO3) with GaN has a strong potential to offer such an improvement. However, the large lattice mismatch between PZT and GaN makes the epitaxial growth of Pb(Zr1-xTix)O-3 on GaN a formidable challenge. This work discusses a novel strain relaxation mechanism observed when MgO is used as a buffer layer, with thicknesses down to a single unit cell, inducing epitaxial growth of high crystallinity Pb(Zr0.52Ti0.48)O-3 (PZT) thin films. The epitaxial PZT films exhibit good ferroelectric properties, showing great promise for future GaN device applications.'));
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000423173800005 Publication Date 2017-11-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2196-7350 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.279 Times cited 15 Open Access Not_Open_Access
Notes ; L.L., Z.L.L., and N.G. contributed equally to this work. L.L. acknowledges financial support from Nano Next NL (Grant no. 7B 04). The authors acknowledge NXP for providing the GaN/AlGaN/Si (111) wafer. N.G. acknowledges funding from the Geconcentreerde Onderzoekacties (GOA) project “Solarpaint” of the University of Antwerp and J.V. acknowledges funding from the Research Foundation Flanders (FWO, Belgium) project 42/FA070100/6088 “nieuwe eigenschappen in complexe Oxides.” N.G. acknowledges the EUROTAPES project (FP7-NMP.2011.2.2-1 Grant no. 280432) which partly funded this study. ; Approved Most recent IF: 4.279
Call Number UA @ lucian @ c:irua:148427UA @ admin @ c:irua:148427 Serial 4872
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Author Ramaneti, R.; Sankaran, K.J.; Korneychuk, S.; Yeh, C.J.; Degutis, G.; Leou, K.C.; Verbeeck, J.; Van Bael, M.K.; Lin, I.N.; Haenen, K.
Title Vertically aligned diamond-graphite hybrid nanorod arrays with superior field electron emission properties Type A1 Journal article
Year 2017 Publication APL materials Abbreviated Journal Apl Mater
Volume (up) 5 Issue 6 Pages 066102
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract A “patterned-seeding technique” in combination with a “nanodiamond masked reactive ion etching process” is demonstrated for fabricating vertically aligned diamond-graphite hybrid (DGH) nanorod arrays. The DGH nanorod arrays possess superior field electron emission (FEE) behavior with a low turn-on field, long lifetime stability, and large field enhancement factor. Such an enhanced FEE is attributed to the nanocomposite nature of theDGHnanorods, which contain sp(2)-graphitic phases in the boundaries of nano-sized diamond grains. The simplicity in the nanorod fabrication process renders the DGH nanorods of greater potential for the applications as cathodes in field emission displays and microplasma display devices. (C) 2017 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000404623000002 Publication Date 2017-06-08
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2166-532x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.335 Times cited 16 Open Access
Notes The authors would like to thank the Methusalem “NANO” network for financial support and Mr. B. Ruttens and Professor Jan D'Haen for technical and experimental assistance. K.J. Sankaran is a Postdoctoral Fellow of the Research Foundation-Flanders (FWO). Approved Most recent IF: 4.335
Call Number UA @ admin @ c:irua:152633 Serial 5369
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Author Wang, Z.; Wang, Y.B.; Yin, J.; Tovari, E.; Yang, Y.; Lin, L.; Holwill, M.; Birkbeck, J.; Perello, D.J.; Xu, S.; Zultak, J.; Gorbachev, R.V.; Kretinin, A.V.; Taniguchi, T.; Watanabe, K.; Morozov, S.V.; Andelkovic, M.; Milovanović, S.P.; Covaci, L.; Peeters, F.M.; Mishchenko, A.; Geim, A.K.; Novoselov, K.S.; Fal'ko, V.I.; Knothe, A.; Woods, C.R.
Title Composite super-moiré lattices in double-aligned graphene heterostructures = Composite super-moire lattices in double-aligned graphene heterostructures Type A1 Journal article
Year 2019 Publication Science Advances Abbreviated Journal
Volume (up) 5 Issue 12 Pages eaay8897
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
Abstract When two-dimensional (2D) atomic crystals are brought into close proximity to form a van der Waals heterostructure, neighbouring crystals may influence each other's properties. Of particular interest is when the two crystals closely match and a moire pattern forms, resulting in modified electronic and excitonic spectra, crystal reconstruction, and more. Thus, moire patterns are a viable tool for controlling the properties of 2D materials. However, the difference in periodicity of the two crystals limits the reconstruction and, thus, is a barrier to the low-energy regime. Here, we present a route to spectrum reconstruction at all energies. By using graphene which is aligned to two hexagonal boron nitride layers, one can make electrons scatter in the differential moire pattern which results in spectral changes at arbitrarily low energies. Further, we demonstrate that the strength of this potential relies crucially on the atomic reconstruction of graphene within the differential moire super cell.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000505069600089 Publication Date 2019-12-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2375-2548 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 71 Open Access
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:165754 Serial 6289
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Author Marinov, D.; de Marneffe, J.-F.; Smets, Q.; Arutchelvan, G.; Bal, K.M.; Voronina, E.; Rakhimova, T.; Mankelevich, Y.; El Kazzi, S.; Nalin Mehta, A.; Wyndaele, P.-J.; Heyne, M.H.; Zhang, J.; With, P.C.; Banerjee, S.; Neyts, E.C.; Asselberghs, I.; Lin, D.; De Gendt, S.
Title Reactive plasma cleaning and restoration of transition metal dichalcogenide monolayers Type A1 Journal article
Year 2021 Publication npj 2D Materials and Applications Abbreviated Journal npj 2D Mater Appl
Volume (up) 5 Issue 1 Pages 17
Keywords A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract The cleaning of two-dimensional (2D) materials is an essential step in the fabrication of future devices, leveraging their unique physical, optical, and chemical properties. Part of these emerging 2D materials are transition metal dichalcogenides (TMDs). So far there is limited understanding of the cleaning of “monolayer” TMD materials. In this study, we report on the use of downstream H<sub>2</sub>plasma to clean the surface of monolayer WS<sub>2</sub>grown by MOCVD. We demonstrate that high-temperature processing is essential, allowing to maximize the removal rate of polymers and to mitigate damage caused to the WS<sub>2</sub>in the form of sulfur vacancies. We show that low temperature in situ carbonyl sulfide (OCS) soak is an efficient way to resulfurize the material, besides high-temperature H<sub>2</sub>S annealing. The cleaning processes and mechanisms elucidated in this work are tested on back-gated field-effect transistors, confirming that transport properties of WS<sub>2</sub>devices can be maintained by the combination of H<sub>2</sub>plasma cleaning and OCS restoration. The low-damage plasma cleaning based on H<sub>2</sub>and OCS is very reproducible, fast (completed in a few minutes) and uses a 300 mm industrial plasma etch system qualified for standard semiconductor pilot production. This process is, therefore, expected to enable the industrial scale-up of 2D-based devices, co-integrated with silicon technology.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000613258900001 Publication Date 2021-01-28
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2397-7132 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access OpenAccess
Notes Daniil Marinov has received funding from the European Union’s Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement No 752164. Ekaterina Voronina, Yuri Mankelevitch, and Tatyana Rakhimova are thankful to the Russian Science Foundation (RSF) for financial support (Grant No. 16-12-10361). This study was carried out using the equipment of the shared research facilities of high-performance computing resources at Lomonosov Moscow State University and the computational resources and services of the HPC core facility CalcUA of the University of Antwerp, and VSC (Flemish Supercomputer Center), funded by the Research Foundation-Flanders (FWO) and the Flemish Government. Patrick With gratefully acknowledges imec’s CTO office for financial support during his stay at imec. The authors thank Mr. Surajit Sutar (imec) for his help during sample electrical characterization, and Patrick Verdonck for lab processing. Jean-François de Marneffe thank Prof. Simone Napolitano from the Free University of Brussels for useful discussions on irreversibly adsorbed polymer layers, and Cédric Huyghebaert (imec) for his continuous support in the framework of the Graphene FET Flagship core project. All authors acknowledge the support of imec’s pilot line and materials characterization and analysis (MCA) group, namely Jonathan Ludwig, Stefanie Sergeant, Thomas Nuytten, Olivier Richard, and Thierry Conard. Finally, Daniil Marinov thank Mikhail Krishtab (imec/KU Leuven) for his help in selecting the optimal plasma etch system for this work. Part of this project has received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement No 649953. Approved Most recent IF: NA
Call Number PLASMANT @ plasmant @c:irua:175871 Serial 6671
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Author Psilodimitrakopoulos, S.; Orekhov, A.; Mouchliadis, L.; Jannis, D.; Maragkakis, G.M.; Kourmoulakis, G.; Gauquelin, N.; Kioseoglou, G.; Verbeeck, J.; Stratakis, E.
Title Optical versus electron diffraction imaging of Twist-angle in 2D transition metal dichalcogenide bilayers Type A1 Journal article
Year 2021 Publication npj 2D Materials and Applications Abbreviated Journal
Volume (up) 5 Issue 1 Pages 77
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Atomically thin two-dimensional (2D) materials can be vertically stacked with van der Waals bonds, which enable interlayer coupling. In the particular case of transition metal dichalcogenide (TMD) bilayers, the relative direction between the two monolayers, coined as twist-angle, modifies the crystal symmetry and creates a superlattice with exciting properties. Here, we demonstrate an all-optical method for pixel-by-pixel mapping of the twist-angle with a resolution of 0.55(degrees), via polarization-resolved second harmonic generation (P-SHG) microscopy and we compare it with four-dimensional scanning transmission electron microscopy (4D STEM). It is found that the twist-angle imaging of WS2 bilayers, using the P-SHG technique is in excellent agreement with that obtained using electron diffraction. The main advantages of the optical approach are that the characterization is performed on the same substrate that the device is created on and that it is three orders of magnitude faster than the 4D STEM. We envisage that the optical P-SHG imaging could become the gold standard for the quality examination of TMD superlattice-based devices.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000694849200001 Publication Date 2021-09-09
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2397-7132 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 4 Open Access OpenAccess
Notes This research has been co-financed by the European Union and Greek national funds through the Operational Program Competitiveness, Entrepreneurship and Innovation, under the call European R & T Cooperation-Grant Act of Hellenic Institutions that have successfully participated in Joint Calls for Proposals of European Networks ERA NETS (National project code: GRAPH-EYE T8 Epsilon Rho Alpha 2-00009 and European code: 26632, FLAGERA). L.M., G.Ko. and G.Ki. acknowledge funding by the Hellenic Foundation for Research and Innovation (H.F.R.I.) under the “First Call for H.F.R.I. Research Projects to support Faculty members and Researchers and the procurement of high-cost research equipment grant” (Project No: HFRI-FM17-3034). GKi, S.P. and G.M.M. acknowledge funding from a research co-financed by Greece and the European Union (European Social Fund-ESF) through the Operational Programme “Human Resources Development, Education and Lifelong Learning 2014-2020” in the context of the project “Crystal quality control of two-dimensional materials and their heterostructures via imaging of their non-linear optical properties” (MIS 5050340)“. J.V acknowledges funding from FWO G093417N ('Compressed sensing enabling low dose imaging in transmission electron microscopy') from the Flanders Research Fund, EU. J.V. and N.G. acknowledge funding from the European Union under the Horizon 2020 programme within a contract for Integrating Activities for Advanced Communities No 823717-ESTEEM3. J.V. N.G. and A.O. acknowledge funding through a GOA project ”Solarpaint" of the University of Antwerp. Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:181610 Serial 6877
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Author Mary Joy, R.; Pobedinskas, P.; Bourgeois, E.; Chakraborty, T.; Görlitz, J.; Herrmann, D.; Noël, C.; Heupel, J.; Jannis, D.; Gauquelin, N.; D'Haen, J.; Verbeeck, J.; Popov, C.; Houssiau, L.; Becher, C.; Nesládek, M.; Haenen, K.
Title Germanium vacancy centre formation in CVD nanocrystalline diamond using a solid dopant source Type A3 Journal article
Year 2023 Publication Science talks Abbreviated Journal Science Talks
Volume (up) 5 Issue Pages 100157
Keywords A3 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date 2023-02-09
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2772-5693 ISBN Additional Links UA library record
Impact Factor Times cited Open Access OpenAccess
Notes Approved Most recent IF: NA
Call Number EMAT @ emat @c:irua:196969 Serial 8791
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Author Saeumel, I.; Ramirez, L.R.; Santolin, J.; Pintado, K.
Title A step to disentangle diversity patterns in Uruguayan grasslands : climatic seasonality, novel land-uses, and landscape context drive diversity of ground flora Type A1 Journal article
Year 2023 Publication Conservation Science and Practice Abbreviated Journal
Volume (up) 5 Issue 9 Pages 1-20
Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
Abstract South American grasslands contain extraordinary biodiversity and play a central role in the subsistence of regional agroecosystems. In recent decades, afforestation, followed by the soybean planting boom, have led to drastic land-use changes at the expense of grasslands. Impacts on local biodiversity have remained understudied. We explored the taxonomic richness and ss-diversity of plants of ground layer (excluding trees and shrubs) at different land uses, its interplay at regional scale with environmental heterogeneity, and at local scale with novel land cover types and landscape configurations. We conducted correlation, principal component, NDMS, and SDR analysis to explore variation of taxonomic richness, richness difference, replacement, and similarity of ground flora as response to environmental filters and land use change across Uruguay. We surveyed 160 plots distributed in 10 land cover types, that is, closed and open native forests, different grasslands, crops, orchards, and timber plantations. We observed overlaying regional patterns driven by seasonality of temperature and precipitation, and land cover shaping taxonomic richness at local scale. Landscape configuration affects diversity patterns of native ground flora, which seems to be sustained mainly by the “old growth grassland” species pool. Taxonomic richness of native species decreases with an increase of distance to grassland. Crops and grasslands harbor a higher number of native species in the ground flora than native forests and timber plantations. The introduction of exotics is driven mostly by crops or highly modified pastures. Diversity patterns only partially reflect the ecoregion concept. Expanding the perspective from conservation in purely natural ecosystems to measures conserving species richness in human-modified landscapes is a powerful tool against species loss in the Anthropocene.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001034673500001 Publication Date 2023-07-24
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2578-4854 ISBN Additional Links UA library record; WoS full record
Impact Factor Times cited Open Access OpenAccess
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:198300 Serial 8828
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Author Nistor, L.C.; van Landuyt, J.; Ralchenko, V.G.; Obratzova, E.D.; Smolin, A.A.
Title Nanocrystalline diamond films: transmission electron microscopy and Raman spectroscopy characterization Type A1 Journal article
Year 1997 Publication Diamond and related materials Abbreviated Journal Diam Relat Mater
Volume (up) 6 Issue Pages 159-168
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos A1997WN37300021 Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0925-9635 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.561 Times cited 116 Open Access
Notes Approved Most recent IF: 2.561; 1997 IF: 1.758
Call Number UA @ lucian @ c:irua:21406 Serial 2249
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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 (up) 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
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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 4119
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Author Kolchina, L. M.; Lyskov, N.V.; Kuznetsov, A.N.; Kazakov, S.M.; Galin, M.Z.; Meledin, A.; Abakumov, A.M.; Bredikhin, S.I.; Mazo, G.N.; Antipov, E.V.
Title Evaluation of Ce-doped Pr2CuO4for potential application as a cathode material for solid oxide fuel cells Type A1 Journal article
Year 2016 Publication RSC advances Abbreviated Journal Rsc Adv
Volume (up) 6 Issue 6 Pages 101029-101037
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Pr2−xCexCuO4 (x = 0.05; 0.1; 0.15) samples were synthesized and systematically characterized towards application as a cathode material for solid oxide fuel cells (SOFCs). High-temperature electrical conductivity, thermal expansion, and electrocatalytic activity in the oxygen reduction reaction (ORR) were examined. The electrical conductivity of Pr2−xCexCuO4 oxides demonstrates semiconducting behavior up to 900 °C. Small Ce-doping (2.5 at%) allows an increase in electrical conductivity from 100 to 130 S cm−1 in air at 500–800 °C. DFT calculations revealed that the density of states directly below the Fermi level, comprised mainly of Cu 3d and O 2p states, is significantly affected by atoms in rare earth positions, which might give an indication of a correlation between calculated electronic structures and measured conducting properties. Ce-doping in Pr2−xCexCuO4 slightly increases TEC from 11.9 × 10−6 K−1 for x = 0 to 14.2 × 10−6 K−1 for x = 0.15. Substitution of 2.5% of Pr atoms in Pr2CuO4 by Ce is effective to enhance the electrochemical performance of the material as a SOFC cathode in the ORR (ASR of Pr1.95Ce0.05CuO4 electrode applied on Ce0.9Gd0.1O1.95 electrolyte is 0.39 Ω cm2 at 750 °C in air). The peak power density achieved for the electrolyte-supported fuel cell with the Pr1.95Ce0.05CuO4 cathode is 150 mW cm−2 at 800 °C
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000387427700044 Publication Date 2016-10-19
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2046-2069 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.108 Times cited 7 Open Access
Notes his work was partially supported by Russian Foundation for Basic Research (grant no. 153820247), Skolkovo Institute of Science and Technology (Center of electrochemical energy), and MSUdevelopment Program up to 2020. K.L.M. is grateful to Haldor Topsøe A/S for the financial support. Approved Most recent IF: 3.108
Call Number EMAT @ emat @ c:irua:136441 Serial 4296
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Author Sankaran, K.J.; Duc Quang Hoang; Korneychuk, S.; Kunuku, S.; Thomas, J.P.; Pobedinskas, P.; Drijkoningen, S.; Van Bael, M.K.; D'Haen, J.; Verbeeck, J.; Leou, K.-C.; Leung, K.T.; Lin, I.-N.; Haenen, K.
Title Hierarchical hexagonal boron nitride nanowall-diamond nanorod heterostructures with enhanced optoelectronic performance Type A1 Journal article
Year 2016 Publication RSC advances Abbreviated Journal Rsc Adv
Volume (up) 6 Issue 93 Pages 90338-90346
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract A superior field electron emission (FEE) source made from a hierarchical heterostructure, where two-dimensional hexagonal boron nitride (hBN) nanowalls were coated on one-dimensional diamond nanorods (DNRs), is fabricated using a simple and scalable method. FEE characteristics of hBN-DNR display a low turn-on field of 6.0 V mu m(-1), a high field enhancement factor of 5870 and a high life-time stability of 435 min. Such an enhancement in the FEE properties of hBN-DNR derives from the distinctive material combination, i.e., high aspect ratio of the heterostructure, good electron transport from the DNR to the hBN nanowalls and efficient field emission of electrons from the hBN nanowalls. The prospective application of these heterostructures is further evidenced by enhanced microplasma devices using hBN-DNR as a cathode, in which the threshold voltage was lowered to 350 V, affirming the role of hBN-DNR in the improvement of electron emission.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000385451800044 Publication Date 2016-09-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2046-2069 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.108 Times cited 8 Open Access
Notes The authors like to thank the financial support of the Research Foundation Flanders (FWO) via Research Projects G.0456.12 and G.0044.13N, the Methusalem “NANO” network. KJ Sankaran, and P Pobedinskas are Postdoctoral Fellows of the Research Foundation-Flanders (FWO). Approved Most recent IF: 3.108
Call Number UA @ lucian @ c:irua:144757UA @ admin @ c:irua:144757 Serial 4662
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Author Hu, L.; Amini, M.N.; Wu, Y.; Jin, Z.; Yuan, J.; Lin, R.; Wu, J.; Dai, Y.; He, H.; Lu, Y.; Lu, J.; Ye, Z.; Han, S.-T.; Ye, J.; Partoens, B.; Zeng, Y.-J.; Ruan, S.
Title Charge transfer doping modulated raman scattering and enhanced stability of black phosphorus quantum dots on a ZnO nanorod Type A1 Journal article
Year 2018 Publication Advanced Optical Materials Abbreviated Journal Adv Opt Mater
Volume (up) 6 Issue 15 Pages 1800440
Keywords A1 Journal article; Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Black phosphorus (BP) has recently triggered an unprecedented interest in the 2D community. However, many of its unique properties are not exploited and the well-known environmental vulnerability is not conquered. Herein, a type-I mixed-dimensional (0D-1D) van der Waals heterojunction is developed, where three-atomic-layer BP quantum dots (QDs) are assembled on a single ZnO nanorod (NR). By adjusting the indium (In) content in ZnO NRs, the degree and even the direction of surface charge transfer doping within the heterojunction can be tuned, which result in selective Raman scattering enhancements between ZnO and BP. The maximal enhancement factor is determined as 4340 for BP QDs with sub-ppm level. Furthermore, an unexpected long-term ambient stability (more than six months) of BP QDs is revealed, which is ascribed to the electron doping from ZnO:In NRs. The first demonstration of selective Raman enhancements between two inorganic semiconductors as well as the improved stability of BP shed light on this emerging 2D material.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000440815200023 Publication Date 2018-05-18
Series Editor Series Title Abbreviated Series Title
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ISSN 2195-1071 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.875 Times cited 37 Open Access Not_Open_Access
Notes ; L. Hu and M. N. Amini contributed equally to this work. This work was supported by the National Natural Science Foundation of China under Grant Nos. 51502178, 81571763 and 81622026, the Shenzhen Science and Technology Project under Grant Nos. JCYJ20150324141711644, JCYJ20170412105400428, KQJSCX20170727101208249 and JCYJ20170302153853962. Parts of the computational calculations were carried out using the HPC infrastructure at University of Antwerp (CalcUA), a division of the Flemish Supercomputer Center VSC, supported financially by the FWO-Vlaanderen and the Flemish Government (EWI Department). L. H. acknowledges the PhD Start-up Fund of Natural Science Foundation of Guangdong Province under Grand No. 2017A030310072. J. Y. acknowledges the funding of Shanghai Jiao Tong University (Nos. YG2016MS51 and YG2017MS54). ; Approved Most recent IF: 6.875
Call Number UA @ lucian @ c:irua:153112UA @ admin @ c:irua:153112 Serial 5082
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Author Lin, A.; Gorbanev, Y.; De Backer, J.; Van Loenhout, J.; Van Boxem, W.; Lemière, F.; Cos, P.; Dewilde, S.; Smits, E.; Bogaerts, A.
Title Non‐Thermal Plasma as a Unique Delivery System of Short‐Lived Reactive Oxygen and Nitrogen Species for Immunogenic Cell Death in Melanoma Cells Type A1 Journal article
Year 2019 Publication Advanced Science Abbreviated Journal Adv Sci
Volume (up) 6 Issue 6 Pages 1802062
Keywords A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT); Center for Oncological Research (CORE)
Abstract
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000462613100001 Publication Date 2019-01-29
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2198-3844 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 9.034 Times cited 39 Open Access OpenAccess
Notes This study was funded in part by the Flanders Research Foundation (grant no. 12S9218N) and the European Marie Sklodowska-Curie Individual Fellowship within Horizon2020 (LTPAM) grant no. 743151). The microsecond-pulsed power supply was purchased following discussions with the C. & J. Nyheim Plasma Institute at Drexel University. The authors would like to thank Dr. Erik Fransen for his expertise and guidance with the statistical models and analysis used here. The authors would also like to thank Dr. Sander Bekeschus of the Leibniz Institute for Plasma Science and Technology for the discussions at conferences and workshops. A.L. contributed to the design and carrying out of all experiments. A.L. also wrote the manuscript. Y.G. contributed to the design and carrying out of experiments involving chemical measurements. Y.G. also contributed to writing the chemical portions of the manuscript. J.D.B. contributed to the design and carrying out of in vivo experiments. J.D.B. also contributed to writing the portions of the manuscript involving animal experiments and care. J.V.L. contributed to the optimization of the calreticulin protocol used in the experiments. W.V.B. contributed to optimization of colorimetric assays used in the experiments. F.L. contributed to mass spectrometry measurements. P.C., S.D., E.S., and A.B. provided workspace, equipment, and valuable discussions for the project. All authors participated in the review of the manuscript.; Flanders Research Foundation, 12S9218N ; European Marie Sklodowska-Curie Individual Fellowship within Horizon2020, 743151 ; Approved Most recent IF: 9.034
Call Number PLASMANT @ plasmant @UA @ admin @ c:irua:156548 Serial 5165
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