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Author Tian, H.; Verbeeck, J.; Brück, S.; Paul, M.; Kufer, D.; Sing, M.; Claessen, R.; Van Tendeloo, G.
Title Interface-induced modulation of charge and polarization in thin film Fe3O4 Type A1 Journal article
Year 2014 Publication Advanced materials Abbreviated Journal Adv Mater
Volume 26 Issue (down) 3 Pages 461-465
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Charge and polarization modulations in Fe3O4 are controlled by taking advantage of interfacial strain effects. The feasibility of oxidation state control by strain modification is demonstrated and it is shown that this approach offers a stable configuration at room temperature. Direct evidence of how a local strain field changes the atomic coordination and introduces atomic displacements leading to polarization of Fe ions is presented.
Address
Corporate Author Thesis
Publisher Place of Publication Weinheim Editor
Language Wos 000334289300011 Publication Date 2013-10-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0935-9648; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 19.791 Times cited 15 Open Access
Notes Vortex; FWO; Countatoms; Hercules ECASJO_; Approved Most recent IF: 19.791; 2014 IF: 17.493
Call Number UA @ lucian @ c:irua:112419UA @ admin @ c:irua:112419 Serial 1694
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Author Maignan, A.; Singh, K.; Simon, C.; Lebedev, O.I.; Martin, C.; Tan, H.; Verbeeck, J.; Van Tendeloo, G.
Title Magnetic and magnetodielectric properties of erbium iron garnet ceramic Type A1 Journal article
Year 2013 Publication Journal of applied physics Abbreviated Journal J Appl Phys
Volume 113 Issue (down) 3 Pages 033905-5
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract An Er3Fe5O12 ceramic has been sintered in oxygen atmosphere at 1400 °C for dielectric measurements. Its structural quality at room temperature has been checked by combining transmission electron microscopy and X-ray diffraction. It crystallizes in the cubic space group Ia3d with a = 12.3488(1). The dielectric permittivity ([variantgreekepsilon]′) and losses (tan δ) measurements as a function of temperature reveal the existence of two anomalies, a broad one between 110 K and 80 K, attributed to the Er3+ spin reorientation, and a second sharper feature at about 45 K associated to the appearance of irreversibility on the magnetic susceptibility curves. In contrast to the lack of magnetic field impact on [variantgreekepsilon]′ for the former anomaly, a complex magnetic field effect has been evidenced below 45 K. The isothermal [variantgreekepsilon]′(H) curves show the existence of positive magnetodielectric effect, reaching a maximum of 0.14% at 3 T and 10 K. Its magnitude decreases as H is further increased. Interestingly, for the lowest H values, a linear regime in the [variantgreekepsilon]′(H) curve is observed. From this experimental study, it is concluded that the [variantgreekepsilon]′ anomaly, starting above the compensation temperature Tc (75 K) and driven by the internal magnetic field, is not sensitive to an applied external magnetic field. Thus, below 45 K, it is the magnetic structure which is responsible for the coupling between spin and charge in this iron garnet.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000313670600042 Publication Date 2013-01-16
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 15 Open Access
Notes Vortex; Countatoms ECASJO_; Approved Most recent IF: 2.068; 2013 IF: 2.185
Call Number UA @ lucian @ c:irua:106182UA @ admin @ c:irua:106182 Serial 1861
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Author Debroye, E.; Yuan, H.; Bladt, E.; Baekelant, W.; Van der Auweraer, M.; Hofkens, J.; Bals, S.; Roeffaers, M.B.J.
Title Facile morphology-controlled synthesis of organolead iodide perovskite nanocrystals using binary capping agents Type A1 Journal article
Year 2017 Publication ChemNanoMat : chemistry of nanomaterials for energy, biology and more Abbreviated Journal Chemnanomat
Volume 3 Issue (down) 3 Pages 223-227
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Controlling the morphology of organolead halide perovskite crystals is crucial to a fundamental understanding of the materials and to tune their properties for device applications. Here, we report a facile solution-based method for morphology-controlled synthesis of rod-like and plate-like organolead halide perovskite nanocrystals using binary capping agents. The morphology control is likely due to an interplay between surface binding kinetics of the two capping agents at different crystal facets. By high-resolution scanning transmission electron microscopy, we show that the obtained nanocrystals are monocrystalline. Moreover, long photoluminescence decay times of the nanocrystals indicate long charge diffusion lengths and low trap/defect densities. Our results pave the way for large-scale solution synthesis of organolead halide perovskite nanocrystals with controlled morphology for future device applications.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000399604300003 Publication Date 2017-01-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2199-692x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.937 Times cited 19 Open Access OpenAccess
Notes ; We acknowledge financial support from the Research Foundation-Flanders (FWO, grant G.0197.11, G.0962.13, G0B39.15, postdoctoral fellowship to E. D. and H. Y.), KU Leuven Research Fund (C14/15/053), the Flemish government through long term structural funding Methusalem (CASAS2, Meth/15/04), the Hercules foundation (HER/11/14), the Belgian Federal Science Policy Office (IAP-PH05), the EC through the Marie Curie ITN project iSwitch (GA-642196) and the ERC project LIGHT (GA307523). S. B. acknowledges financial support from European Research Council (ERC Starting Grant # 335078-COLOURATOMS). E. B. gratefully acknowledges financial support by the Flemish Fund for Scientific Research (FWO Vlaanderen). ; ecas_Sara Approved Most recent IF: 2.937
Call Number UA @ lucian @ c:irua:143678UA @ admin @ c:irua:143678 Serial 4656
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Author Tan, X.; McCabe, E.E.; Orlandi, F.; Manuel, P.; Batuk, M.; Hadermann, J.; Deng, Z.; Jin, C.; Nowik, I.; Herber, R.; Segre, C.U.; Liu, S.; Croft, M.; Kang, C.-J.; Lapidus, S.; Frank, C.E.; Padmanabhan, H.; Gopalan, V.; Wu, M.; Li, M.-R.; Kotliar, G.; Walker, D.; Greenblatt, M.
Title MnFe0.5Ru0.5O3 : an above-room-temperature antiferromagnetic semiconductor Type A1 Journal article
Year 2019 Publication Journal of materials chemistry C : materials for optical and electronic devices Abbreviated Journal J Mater Chem C
Volume 7 Issue (down) 3 Pages 509-522
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract A transition-metal-only MnFe0.5Ru0.5O3 polycrystalline oxide was prepared by a reaction of starting materials MnO, MnO2, Fe2O3, RuO2 at 6 GPa and 1873 K for 30 minutes. A combination of X-ray and neutron powder diffraction refinements indicated that MnFe0.5Ru0.5O3 adopts the corundum (alpha-Fe2O3) structure type with space group R (3) over barc, in which all metal ions are disordered. The centrosymmetric nature of the MnFe0.5Ru0.5O3 structure is corroborated by transmission electron microscopy, lack of optical second harmonic generation, X-ray absorption near edge spectroscopy, and Mossbauer spectroscopy. X-ray absorption near edge spectroscopy of MnFe0.5Ru0.5O3 showed the oxidation states of Mn, Fe, and Ru to be 2+/3+, 3+, and similar to 4+, respectively. Resistivity measurements revealed that MnFe0.5Ru0.5O3 is a semiconductor. Magnetic measurements and magnetic structure refinements indicated that MnFe0.5Ru0.5O3 orders antiferromagnetically around 400 K, with magnetic moments slightly canted away from the c axis. Fe-57 Mossbauer confirmed the magnetic ordering and Fe3+ (S = 5/2) magnetic hyperfine splitting. First principles calculations are provided to understand the electronic structure more thoroughly. A comparison of synthesis and properties of MnFe0.5Ru0.5O3 and related corundum Mn2BB'O-6 derivatives is discussed.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000458780300004 Publication Date 2018-11-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2050-7526; 2050-7534 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 5.256 Times cited 1 Open Access Not_Open_Access
Notes ; M. G. thanks the NSF-DMR-1507252 grant of the United States. X. T. was supported by the “Center for Computational Design of Functional Strongly Correlated Materials and Theoretical Spectroscopy'' under DOE Grant No. DE-FOA-0001276. G. K. and C. J. K. were supported by the Air Force Office of Scientific Research. MRCAT operations are supported by the Department of Energy and the MRCAT member institutions. EEM is grateful to the Leverhulme Trust (RPG-2017-362). M. R. Li and M. X. Wu are supported by the ”One Thousand Youth Talents'' Program of China. Use of the Advanced Photon Source at Argonne National Laboratory was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357. Part of this research used the ISS, 8-ID and TES, 8-BM beamlines at the National Synchrotron Light Source II (NSLS-II), a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Brookhaven National Laboratory under Contract No. DE-SC0012704. Without the valuable aid/support of the NSLS-II staff scientists Eli Stavitski, Klaus Attenkofer, and Paul Northrup this phase of the work could not have been performed. The work at IOPCAS was supported by NSF & MOST of China through research projects. H. R. and V. G. acknowledge NSF-MRSEC Center for Nanoscale Science at Penn State through the grant number DMR-1420620. The authors would like to thank Ms Jean Hanley at Lamont-Doherty Earth Observatory in Columbia University for making the high-pressure assemblies. The authors acknowledge the science and technology facility council (STFC) UK for the provision of neutron beam time. The authors would like to thank Daniel Nye for help on the Rigaku SmartLab X-ray diffractometer instrument in the Materials Characterization Laboratory at the ISIS Neutron and Muon Source. ; Approved Most recent IF: 5.256
Call Number UA @ admin @ c:irua:157564 Serial 5264
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Author Dehhaghi, S.; Choobchian, S.; Ghobadian, B.; Farhadian, H.; Viira, A.-H.; Stefanie, H.I.; Van Passel, S.; Azadi, H.
Title Five-year development plans of renewable energy policies in Iran : a content analysis Type A1 Journal article
Year 2022 Publication Sustainability Abbreviated Journal Sustainability-Basel
Volume 14 Issue (down) 3 Pages 1501
Keywords A1 Journal article; Engineering sciences. Technology; Engineering Management (ENM)
Abstract Renewable energy (RE) policies can play an effective role in the development of renewable resources. The main goal of this paper was to conduct a content analysis on RE development policies in Iran's five-year National Development Plan (NDP) by investigating upstream national documents. To achieve the goal, 29 upstream documents related to RE were identified and analyzed through a systematic literature review. Then, a qualitative content analysis was applied to analyze the documents. The results showed that Iran's current RE policies need to be reviewed, reformed, and strengthened. For example, lack of sufficient attention to renewable heat and fuel was one of the deficiencies of RE policies in Iran's five-year NDP. The decentralization of policymaking in the unified organization was also one of the weaknesses in the policymaking process of the RE. Iran can develop sustainable and clean RE policies by using sources such as solar, wind, geothermal, hydropower, wave, and tidal power. The paper concludes that, although RE policies have the potential for development in Iran due to environmental, social, and economic advantages, they could face some infrastructural, managerial, socio-cultural, and economic challenges. Accordingly, effective and innovative policymaking is required to meet such challenges.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000754912800001 Publication Date 2022-01-28
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2071-1050 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.9 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 3.9
Call Number UA @ admin @ c:irua:186501 Serial 7358
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Author Tan, H.; Turner, S.; Yucelen, E.; Verbeeck, J.; Van Tendeloo, G.
Title 2D atomic mapping of oxidation states in transition metal oxides by scanning transmission electron microscopy and electron energy-loss spectroscopy : reply Type Editorial
Year 2012 Publication Physical review letters Abbreviated Journal Phys Rev Lett
Volume 108 Issue (down) 25 Pages 259702
Keywords Editorial; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000305568700038 Publication Date 2012-06-19
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0031-9007 ISBN Additional Links UA library record; WoS full record
Impact Factor 8.462 Times cited Open Access
Notes Approved Most recent IF: 8.462; 2012 IF: 7.943
Call Number UA @ admin @ c:irua:100293 Serial 5370
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Author Jungbauer, M.; Huehn, S.; Egoavil, R.; Tan, H.; Verbeeck, J.; Van Tendeloo, G.; Moshnyaga, V.
Title Atomic layer epitaxy of Ruddlesden-Popper SrO(SrTiO3)n films by means of metalorganic aerosol deposition Type A1 Journal article
Year 2014 Publication Applied physics letters Abbreviated Journal Appl Phys Lett
Volume 105 Issue (down) 25 Pages 251603
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We report an atomic layer epitaxial growth of Ruddlesden-Popper (RP) thin films of SrO(SrTiO3)(n) (n = infinity, 2, 3, 4) by means of metalorganic aerosol deposition (MAD). The films are grown on SrTiO3(001) substrates by means of a sequential deposition of Sr-O/Ti-O-2 atomic monolayers, monitored in-situ by optical ellipsometry. X-ray diffraction and transmission electron microscopy (TEM) reveal the RP structure with n = 2-4 in accordance with the growth recipe. RP defects, observed by TEM in a good correlation with the in-situ ellipsometry, mainly result from the excess of SrO. Being maximal at the film/substrate interface, the SrO excess rapidly decreases and saturates after 5-6 repetitions of the SrO(SrTiO3)(4) block at the level of 2.4%. This identifies the SrTiO3 substrate surface as a source of RP defects under oxidizing conditions within MAD. Advantages and limitations of MAD as a solution-based and vacuum-free chemical deposition route were discussed in comparison with molecular beam epitaxy. (C) 2014 AIP Publishing LLC.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000346914000007 Publication Date 2014-12-26
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 32 Open Access
Notes 246102 IFOX; 278510 VORTEX; 246791 COUNTATOMS; Hercules; 312483 ESTEEM2; esteem2jra3 ECASJO; Approved Most recent IF: 3.411; 2014 IF: 3.302
Call Number UA @ lucian @ c:irua:122830UA @ admin @ c:irua:122830 Serial 172
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Author Yang, S.; Liu, Z.; An, H.; Arnouts, S.; de Ruiter, J.; Rollier, F.; Bals, S.; Altantzis, T.; Figueiredo, M.C.; Filot, I.A.W.; Hensen, E.J.M.; Weckhuysen, B.M.; van der Stam, W.
Title Near-unity electrochemical CO₂ to CO conversion over Sn-doped copper oxide nanoparticles Type A1 Journal article
Year 2022 Publication ACS catalysis Abbreviated Journal Acs Catal
Volume 12 Issue (down) 24 Pages 15146-15156
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT)
Abstract Bimetallic electrocatalysts have emerged as a viable strategy to tune the electrocatalytic CO2 reduction reaction (eCO2RR) for the selective production of valuable base chemicals and fuels. However, obtaining high product selectivity and catalyst stability remain challenging, which hinders the practical application of eCO2RR. In this work, it was found that a small doping concentration of tin (Sn) in copper oxide (CuO) has profound influence on the catalytic performance, boosting the Faradaic efficiency (FE) up to 98% for carbon monoxide (CO) at -0.75 V versus RHE, with prolonged stable performance (FE > 90%) for up to 15 h. Through a combination of ex situ and in situ characterization techniques, the in situ activation and reaction mechanism of the electrocatalyst at work was elucidated. In situ Raman spectroscopy measurements revealed that the binding energy of the crucial adsorbed *CO intermediate was lowered through Sn doping, thereby favoring gaseous CO desorption. This observation was confirmed by density functional theory, which further indicated that hydrogen adsorption and subsequent hydrogen evolution were hampered on the Sn-doped electrocatalysts, resulting in boosted CO formation. It was found that the pristine electrocatalysts consisted of CuO nanoparticles decorated with SnO2 domains, as characterized by ex situ high-resolution scanning transmission electron microscopy and X-ray photoelectron spectroscopy measurements. These pristine nanoparticles were subsequently in situ converted into a catalytically active bimetallic Sn-doped Cu phase. Our work sheds light on the intimate relationship between the bimetallic structure and catalytic behavior, resulting in stable and selective oxide-derived Sn-doped Cu electrocatalysts.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000900052400001 Publication Date 2022-11-28
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2155-5435 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 12.9 Times cited 16 Open Access OpenAccess
Notes B.M.W., S.Y., M.C.F., E.J.M.H., and W.v.d.S. acknowledge support from the Strategic UU-TU/e Alliance project ?Joint Centre for Chemergy Research?. S.B. acknowledges support from the European Research Council (ERC Consolidator grant #815128 REALNANO) . Z.L. acknowledges financial support of the China Scholarship Council and the Netherlands Organization for Scientific Research for access to computa-tional resources for carrying out the DFT calculations reported in this work. S.A. and T.A. acknowledge funding from theUniversity of Antwerp Research fund (BOF) . The authors also thank Dr. Jochem Wijten and Joris Janssens (Inorganic Chemistry and Catalysis, Utrecht University) for helpful technical support. Sander Deelen (Faculty of Science, Utrecht University) is acknowledged for the design of the in situ XRD cell. Approved Most recent IF: 12.9
Call Number UA @ admin @ c:irua:192742 Serial 7325
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Author Yuan, H.F.; Xu, W.; Zhao, X.N.; Song, D.; Zhang, G.R.; Xiao, Y.M.; Ding, L.; Peeters, F.M.
Title Quantum and transport mobilities of a Na3Bi-based three-dimensional Dirac system Type A1 Journal article
Year 2019 Publication Physical review B Abbreviated Journal Phys Rev B
Volume 99 Issue (down) 23 Pages 235303
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The electronic and transport properties of a three-dimensional (3D) Dirac system are investigated theoretically, which is motivated by recent experimental measurements on quantum and transport mobilities in the 3D Dirac semimetal Na3Bi by J. Xiong et al. [Science 350, 413 (2015); Europhys. Lett. 114, 27002 (2016)]. The electron Hamiltonian is taken from a simplified k center dot p approach. From the obtained electronic band structure and the Fermi energy, we explain why the anomalous effect induced by the chiral anomaly and the Berry curvature in the energy band can be observed experimentally in magnetotransport coefficients in both low-and high-density samples. Moreover, the quantum and transport mobilities are calculated on the basis of the momentum-balance equation derived from a semiclassical Boltzmann equation with the electron-impurity interaction. The quantum and transport mobilities obtained from this study agree both qualitatively and quantitatively with those measured experimentally. We also examine the electron mobilities along different crystal directions in Na3Bi and find them largely anisotropic. The theoretical findings from this work can be helpful in gaining an in-depth understanding of the experimental results and of the basic electronic and transport properties of newly developed 3D Dirac systems.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000471983500006 Publication Date 2019-06-17
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2469-9969; 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 3 Open Access
Notes ; ; Approved Most recent IF: 3.836
Call Number UA @ admin @ c:irua:161329 Serial 5425
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Author Egoavil, R.; Tan, H.; Verbeeck, J.; Bals, S.; Smith, B.; Kuiper, B.; Rijnders, G.; Koster, G.; Van Tendeloo, G.
Title Atomic scale investigation of a PbTiO3/SrRuO3/DyScO3 heterostructure Type A1 Journal article
Year 2013 Publication Applied physics letters Abbreviated Journal Appl Phys Lett
Volume 102 Issue (down) 22 Pages 223106-5
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract An epitaxial PbTiO3 thin film grown on self-organized crystalline SrRuO3 nanowires deposited on a DyScO3 substrate with ordered DyO and ScO2 chemical terminations is investigated by transmission electron microscopy. In this PbTiO3/SrRuO3/DyScO3 heterostructure, the SrRuO3 nanowires are assumed to grow on only one type of substrate termination. Here, we report on the structure, morphology, and chemical composition analysis of this heterostructure. Electron energy loss spectroscopy reveals the exact termination sequence in this complex structure. The energy loss near-edge structure of the Ti-L-2,L-3, Sc-L-2,L-3, and O K edges shows intrinsic interfacial electronic reconstruction. Furthermore, PbTiO3 domain walls are observed to start at the end of the nanowires resulting in atomic steps on the film surface. (C) 2013 AIP Publishing LLC.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000320621600070 Publication Date 2013-06-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0003-6951; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.411 Times cited 12 Open Access
Notes Ifox; Esteem2; Countatoms; Vortex; esteem2jra3 ECASJO; Approved Most recent IF: 3.411; 2013 IF: 3.515
Call Number UA @ lucian @ c:irua:109606UA @ admin @ c:irua:109606 Serial 185
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Author He, Z.; Tian, H.; Deng, G.; Xu, Q.; Van Tendeloo, G.
Title Microstructure of bilayer manganite PrCa2Mn2O7 showing charge/orbital ordering Type A1 Journal article
Year 2013 Publication Applied physics letters Abbreviated Journal Appl Phys Lett
Volume 102 Issue (down) 21 Pages 212902-212905
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The microstructure of the charge/orbital ordering Ruddleden-Popper phase PrCa2Mn2O7 was studied by transmission electron microscopy along both the [001] and the [110] orientation. Three coexisting charge/orbital ordering phases CO1, CO2, and CO3 were observed along the [001] orientation at room temperature. Different from the one-dimensional modulation in the CO1 and CO2 phase, the CO3 phase is characterized by two sets of mutually perpendicular structural modulations. From [110] high angle annular dark field-scanning transmission electron microscopy, we found that the Pr atoms locate in-between the bilayer MnO6 octahedra, which is different from the previous reports.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000320620400056 Publication Date 2013-05-29
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0003-6951; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.411 Times cited 4 Open Access
Notes Countatoms Approved Most recent IF: 3.411; 2013 IF: 3.515
Call Number UA @ lucian @ c:irua:108762 Serial 2068
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Author Verbeeck, J.; Guzzinati, G.; Clark, L.; Juchtmans, R.; Van Boxem, R.; Tian, H.; Béché, A.; Lubk, A.; Van Tendeloo, G.
Title Shaping electron beams for the generation of innovative measurements in the (S)TEM Type A1 Journal article
Year 2014 Publication Comptes rendus : physique Abbreviated Journal Cr Phys
Volume 15 Issue (down) 2-3 Pages 190-199
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract In TEM, a typical goal consists of making a small electron probe in the sample plane in order to obtain high spatial resolution in scanning transmission electron microscopy. In order to do so, the phase of the electron wave is corrected to resemble a spherical wave compensating for aberrations in the magnetic lenses. In this contribution, we discuss the advantage of changing the phase of an electron wave in a specific way in order to obtain fundamentally different electron probes opening up new applications in the (S)TEM. We focus on electron vortex states as a specific family of waves with an azimuthal phase signature and discuss their properties, production and applications. The concepts presented here are rather general and also different classes of probes can be obtained in a similar fashion, showing that electron probes can be tuned to optimize a specific measurement or interaction.
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Corporate Author Thesis
Publisher Place of Publication Paris Editor
Language Wos 000334013600009 Publication Date 2014-02-01
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1631-0705; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.048 Times cited 22 Open Access
Notes Vortex ECASJO_; Approved Most recent IF: 2.048; 2014 IF: 2.035
Call Number UA @ lucian @ c:irua:116946UA @ admin @ c:irua:116946 Serial 2992
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Author Monico, L.; Janssens, K.; Miliani, C.; Brunetti, B.G.; Vagnini, M.; Vanmeert, F.; Falkenberg, G.; Abakumov, A.; Lu, Y.; Tian, H.; Verbeeck, J.; Radepont, M.; Cotte, M.; Hendriks, E.; Geldof, M.; van der Loeff, L.; Salvant, J.; Menu, M.;
Title Degradation process of lead chromate in paintings by Vincent van Gogh studied by means of spectromicroscopic methods : 3 : synthesis, characterization, and detection of different crystal forms of the chrome yellow pigment Type A1 Journal article
Year 2013 Publication Analytical chemistry Abbreviated Journal Anal Chem
Volume 85 Issue (down) 2 Pages 860-867
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract The painter, Vincent van Gogh, and some of his contemporaries frequently made use of the pigment chrome yellow that is known to show a tendency toward darkening. This pigment may correspond to various chemical compounds such as PbCrO4 and PbCr1-xSxO4, that may each be present in various crystallographic forms with different tendencies toward degradation. Investigations by X-ray diffraction (XRD), mid-Fourier Transform infrared (FTIR), and Raman instruments (benchtop and portable) and synchrotron radiation-based micro-XRD and X-ray absorption near edge structure spectroscopy performed on oil-paint models, prepared with in-house synthesized PbCrO4 and PbCr1-xSxO4, permitted us to characterize the spectroscopic features of the various forms. On the basis of these results, an extended study has been carried out on historic paint tubes and on embedded paint microsamples taken from yellow-orange/pale yellow areas of 12 Van Gogh paintings, demonstrating that Van Gogh effectively made use of different chrome yellow types. This conclusion was also confirmed by in situ mid-FTIR investigations on Van Goghs Portrait of Gauguin (Van Gogh Museum, Amsterdam).
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Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000313668400031 Publication Date 2012-10-10
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0003-2700;1520-6882; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.32 Times cited 79 Open Access
Notes Goa; Fwo Approved Most recent IF: 6.32; 2013 IF: 5.825
Call Number UA @ lucian @ c:irua:108707UA @ admin @ c:irua:108707 Serial 631
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Author Tian, H.; Schryvers, D.; Mohanchandra, K.P.; Carman, G.P.; van Humbeeck, J.
Title Fabrication and characterization of functionally graded Ni-Ti multilayer thin films Type A1 Journal article
Year 2009 Publication Functional materials letters Abbreviated Journal Funct Mater Lett
Volume 2 Issue (down) 2 Pages 61-66
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract A functionally graded multilayer NiTi thin film was deposited on a SiO2/Si substrate by d.c. sputtering using a ramped heated NiTi alloy target. The stand-alone films were crystallized at 500°C in vacuum better than 10-7 Torr. Transmission electron microscopy micrographs taken along the film cross section show two distinct regions, thin and thick, with weak R and B2 phases, respectively. The film compositions along the thickness were measured and quantified using the standard-less EELSMODEL method. The film deposited during the initial thermal ramp (thin regions) displays an average of 54 at.% Ni while the film deposited at a more elevated target temperature (thick regions) shows about 51 at.% Ni.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000271077000003 Publication Date 2009-07-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1793-6047;1793-7213; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.234 Times cited 9 Open Access
Notes Fwo Approved Most recent IF: 1.234; 2009 IF: 2.561
Call Number UA @ lucian @ c:irua:77655 Serial 1165
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Author Tian, H.; Schryvers, D.; Liu, D.; Jiang, Q.; van Humbeeck, J.
Title Stability of Ni in nitinol oxide surfaces Type A1 Journal article
Year 2011 Publication Acta biomaterialia Abbreviated Journal Acta Biomater
Volume 7 Issue (down) 2 Pages 892-899
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The stability of Ni in titanium oxide surface layers on nitinol wires known to release certain amounts of Ni was investigated by first principles density functional theory and transmission electron microscopy. The oxides were identified as a combination of TiO and TiO2 depending on the thickness of the layer. The calculations indicate that free Ni atoms can exist in TiO at ambient temperature while Ni particles form in TiO2, which was confirmed by the transmission electron microscopy observations. The results are discussed with respect to surface stability and Ni release due to free Ni atoms and Ni particles.
Address
Corporate Author Thesis
Publisher Place of Publication S.l. Editor
Language Wos 000286707700047 Publication Date 2010-09-17
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1742-7061; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.319 Times cited 39 Open Access
Notes Fwo Approved Most recent IF: 6.319; 2011 IF: 4.865
Call Number UA @ lucian @ c:irua:85998 Serial 3128
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Author d' Hondt, H.; Hadermann, J.; Abakumov, A.M.; Kalyuzhnaya, A.S.; Rozova, M.G.; Tsirlin, A.A.; Tan, H.; Verbeeck, J.; Antipov, E.V.; Van Tendeloo, G.
Title Synthesis, crystal structure and magnetic properties of the Sr2Al0.78Mn1.22O5.2 anion-deficient layered perovskite Type A1 Journal article
Year 2009 Publication Journal of solid state chemistry Abbreviated Journal J Solid State Chem
Volume 182 Issue (down) 2 Pages 356-363
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract A new layered perovskite Sr2Al0.78Mn1.22O5.2 has been synthesized by solid state reaction in a sealed evacuated silica tube. The crystal structure has been determined using electron diffraction, high-resolution electron microscopy, and high-angle annular dark field imaging and refined from X-ray powder diffraction data (space group P4/mmm, a=3.89023(5) Å, c=7.8034(1) Å, RI=0.023, RP=0.015). The structure is characterized by an alternation of MnO2 and (Al0.78Mn0.22)O1.2 layers. Oxygen atoms and vacancies, as well as the Al and Mn atoms in the (Al0.78Mn0.22)O1.2 layers are disordered. The local atomic arrangement in these layers is suggested to consist of short fragments of brownmillerite-type tetrahedral chains of corner-sharing AlO4 tetrahedra interrupted by MnO6 octahedra, at which the chain fragments rotate over 90°. This results in an averaged tetragonal symmetry. This is confirmed by the valence state of Mn measured by EELS. The relationship between the Sr2Al0.78Mn1.22O5.2 tetragonal perovskite and the parent Sr2Al1.07Mn0.93O5 brownmillerite is discussed. Magnetic susceptibility measurements indicate spin glass behavior of Sr2Al0.78Mn1.22O5.2. The lack of long-range magnetic ordering contrasts with Mn-containing brownmillerites and is likely caused by the frustration of interlayer interactions due to presence of the Mn atoms in the (Al0.78Mn0.22)O1.2 layers.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000263124700022 Publication Date 2008-11-14
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-4596; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.299 Times cited 12 Open Access
Notes Iap Vi Approved Most recent IF: 2.299; 2009 IF: 2.340
Call Number UA @ lucian @ c:irua:72943 Serial 3450
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Author Burriel, M.; Casa-Cabanas, M.; Zapata, J.; Tan, H.; Verbeeck, J.; Solis, C.; Roqueta, J.; Skinner, S.J.; Kilner, J.A.; Van Tendeloo, G.; Santiso, J.
Title Influence of the microstructure on the high-temperature transport properties of GdBaCo2O5.5+\delta epitaxial films Type A1 Journal article
Year 2010 Publication Chemistry of materials Abbreviated Journal Chem Mater
Volume 22 Issue (down) 19 Pages 5512-5520
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Epitaxial thin films of GdBaCo2O5.5+δ (GBCO) grown by pulsed laser deposition have been studied as a function of deposition conditions. The variation in film structure, domain orientation, and microstructure upon deviations in the cation composition have been correlated with the charge transport properties of the films. The epitaxial GBCO films mainly consist of single- and double-perovskite regions that are oriented in different directions depending on the deposition temperature. Additionally, cobalt depletion induces the formation of a high density of stacking defects in the films, consisting of supplementary GdO planes along the c-axis of the material. The presence of such defects progressively reduces the electrical conductivity. The films closer to the stoichiometric composition have shown p-type electronic conductivity at high pO2 with values as high as 800 S/cm at 330 °C in 1 atm O2, and with a pO2 power dependence with an exponent as low as 1/25, consistent with the behavior reported for bulk GBCO. These values place GBCO thin films as a very promising material to be applied as cathodes in intermediate temperature solid oxide fuel cells.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000282471000013 Publication Date 2010-09-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0897-4756;1520-5002; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 9.466 Times cited 17 Open Access
Notes Fwo; Esteem 026019 Approved Most recent IF: 9.466; 2010 IF: 6.400
Call Number UA @ lucian @ c:irua:85412UA @ admin @ c:irua:85412 Serial 1648
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Author Hadermann, J.; Abakumov, A.M.; Perkisas, T.; d' Hondt, H.; Tan, H.; Verbeeck, J.; Filonenko, V.P.; Antipov, E.V.; Van Tendeloo, G.
Title New perovskite-based manganite Pb2Mn2O5 Type A1 Journal article
Year 2010 Publication Journal of solid state chemistry Abbreviated Journal J Solid State Chem
Volume 183 Issue (down) 183 Pages 2190-2195
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract A new perovskite based compound Pb2Mn2O5 has been synthesized using a high pressure high temperature technique. The structure model of Pb2Mn2O5 is proposed based on electron diffraction, high angle annular dark field scanning transmission electron microscopy and high resolution transmission electron microscopy. The compound crystallizes in an orthorhombic unit cell with parameters a=5.736(1)Å≈√2a p p p (a p the parameter of the perovskite subcell) and space group Pnma. The Pb2Mn2O5 structure consists of quasi two-dimensional perovskite blocks separated by 1/2[110] p (1̄01) p crystallographic shear planes. The blocks are connected to each other by chains of edge-sharing MnO5 distorted tetragonal pyramids. The chains of MnO5 pyramids and the MnO6 octahedra of the perovskite blocks delimit six-sided tunnels accommodating double chains of Pb atoms. The tunnels and pyramidal chains adopt two mirror-related configurations (left L and right R) and layers consisting of chains and tunnels of the same configuration alternate in the structure according to an -LRLR-sequence. The sequence is sometimes locally violated by the appearance of -LL- or -RR-fragments. A scheme is proposed with a JahnTeller distortion of the MnO6 octahedra with two long and two short bonds lying in the ac plane, along two perpendicular orientations within this plane, forming a d-type pattern.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000282139600041 Publication Date 2010-07-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-4596; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.299 Times cited 8 Open Access
Notes Fwo; Bof; Esteem 026019 Approved Most recent IF: 2.299; 2010 IF: 2.261
Call Number UA @ lucian @ c:irua:85472UA @ admin @ c:irua:85472 Serial 2332
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Author Palgrave, R.G.; Borisov, P.; Dyer, M.S.; McMitchell, S.R.C.; Darling, G.R.; Claridge, J.B.; Batuk, M.; Tan, H.; Tian, H.; Verbeeck, J.; Hadermann, J.; Rosseinsky, M.J.;
Title Artificial construction of the layered Ruddlesden-Popper manganite La2Sr2Mn3O10 by reflection high energy electron diffraction monitored pulsed laser deposition Type A1 Journal article
Year 2012 Publication Journal of the American Chemical Society Abbreviated Journal J Am Chem Soc
Volume 134 Issue (down) 18 Pages 7700-7714
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Pulsed laser deposition has been used to artificially construct the n = 3 Ruddlesden Popper structure La2Sr2Mn3O10 in epitaxial thin film form by sequentially layering La1-xSrxMnO3 and SrO unit cells aided by in situ reflection high energy electron diffraction monitoring. The interval deposition technique was used to promote two-dimensional SrO growth. X-ray diffraction and cross-sectional transmission electron microscopy indicated that the trilayer structure had been formed. A site ordering was found to differ from that expected thermodynamically, with the smaller Sr2+ predominantly on the R site due to kinetic trapping of the deposited cation sequence. A dependence of the out-of-plane lattice parameter on growth pressure was interpreted as changing the oxygen content of the films. Magnetic and transport measurements on fully oxygenated films indicated a frustrated magnetic ground state characterized as a spin glass-like magnetic phase with the glass temperature T-g approximate to 34 K. The magnetic frustration has a clear in-plane (ab) magnetic anisotropy, which is maintained up to temperatures of 150 K. Density functional theory calculations suggest competing antiferromagnetic and ferromagnetic long-range orders, which are proposed as the origin of the low-temperature glassy state.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000303696200029 Publication Date 2012-03-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0002-7863;1520-5126; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 13.858 Times cited 27 Open Access
Notes Fwo; Esteem 026019 Approved Most recent IF: 13.858; 2012 IF: 10.677
Call Number UA @ lucian @ c:irua:98947UA @ admin @ c:irua:98947 Serial 153
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Author Filez, M.; Redekop, E.A.; Galvita, V.V.; Poelman, H.; Meledina, M.; Turner, S.; Van Tendeloo, G.; Bell, A.T.; Marin, G.B.
Title The role of hydrogen during Pt-Ga nanocatalyst formation Type A1 Journal article
Year 2016 Publication Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys
Volume 18 Issue (down) 18 Pages 3234-3243
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Hydrogen plays an essential role during the in situ assembly of tailored catalytic materials, and serves as key ingredient in multifarious chemical reactions promoted by these catalysts. Despite intensive debate for several decades, the existence and nature of hydrogen-involved mechanisms – such as hydrogen-spillover, surface migration – have not been unambiguously proven and elucidated up to date. Here, Pt-Ga alloy formation is used as a probe reaction to study the behavior and atomic transport of H and Ga, starting from Pt nanoparticles on hydrotalcite-derived Mg(Ga)(Al)Ox supports. In situ XANES spectroscopy, time-resolved TAP kinetic experiments, HAADF-STEM imaging and EDX mapping are combined to probe Pt, Ga and H in a series of H2 reduction experiments up to 650 degrees C. Mg(Ga)(Al)Ox by itself dissociates hydrogen, but these dissociated hydrogen species do not induce significant reduction of Ga3+ cations in the support. Only in the presence of Pt, partial reduction of Ga3+ into Gadelta+ is observed, suggesting that different reaction mechanisms dominate for Pt- and Mg(Ga)(Al)Ox-dissociated hydrogen species. This partial reduction of Ga3+ is made possible by Pt-dissociated H species which spillover onto non-reducible Mg(Al)Ox or partially reducible Mg(Ga)(Al)Ox and undergo long-range transport over the support surface. Moderately mobile Gadelta+Ox migrates towards Pt clusters, where Gadelta+ is only fully reduced to Ga0 on condition of immediate stabilization inside Pt-Ga alloyed nanoparticles.
Address Laboratory for Chemical Technology (LCT), Ghent University, Technologiepark 914, B-9052 Ghent, Belgium. hilde.poelman@ugent.be
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Wos 000369506000106 Publication Date 2016-01-04
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 10 Open Access
Notes This work was supported by the Fund for Scientific Research Flanders (FWO: G.0209.11), the ‘Long Term Structural Methusalem Funding by the Flemish Government’, the IAP 7/05 Interuniversity Attraction Poles Programme – Belgian State – Belgian Science Policy, and the Fund for Scientific Research Flanders (FWO-Vlaanderen) in supplying financing of beam time at the DUBBLE beam line of the ESRF and travel costs and a postdoctoral fellowship for S.T. The authors acknowledge the assistance from D. Banerjee (XAS campaign 26-01-979) at DUBBLE. E. A. Redekop acknowledges the Marie Curie International Incoming Fellowship granted by the European Commission (Grant Agreement No. 301703). The authors also express their gratitude to V. Bliznuk for acquisition of the TEM images. Approved Most recent IF: 4.123
Call Number c:irua:132315 Serial 4000
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Author Yang, S.; An, H.; Anastasiadou, D.; Xu, W.; Wu, L.; Wang, H.; de Ruiter, J.; Arnouts, S.; Figueiredo, M.C.; Bals, S.; Altantzis, T.; van der Stam, W.; Weckhuysen, B.M.
Title Waste-derived copper-lead electrocatalysts for CO₂ reduction Type A1 Journal article
Year 2022 Publication ChemCatChem Abbreviated Journal Chemcatchem
Volume 14 Issue (down) 18 Pages e202200754-11
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT)
Abstract It remains a real challenge to control the selectivity of the electrocatalytic CO2 reduction (eCO(2)R) reaction to valuable chemicals and fuels. Most of the electrocatalysts are made of non-renewable metal resources, which hampers their large-scale implementation. Here, we report the preparation of bimetallic copper-lead (CuPb) electrocatalysts from industrial metallurgical waste. The metal ions were extracted from the metallurgical waste through simple chemical treatment with ammonium chloride, and CuxPby electrocatalysts with tunable compositions were fabricated through electrodeposition at varying cathodic potentials. X-ray spectroscopy techniques showed that the pristine electrocatalysts consist of Cu-0, Cu1+ and Pb2+ domains, and no evidence for alloy formation was found. We found a volcano-shape relationship between eCO(2)R selectivity toward two electron products, such as CO, and the elemental ratio of Cu and Pb. A maximum Faradaic efficiency towards CO was found for Cu9.00Pb1.00, which was four times higher than that of pure Cu, under the same electrocatalytic conditions. In situ Raman spectroscopy revealed that the optimal amount of Pb effectively improved the reducibility of the pristine Cu1+ and Pb2+ domains to metallic Cu and Pb, which boosted the selectivity towards CO by synergistic effects. This work provides a framework of thinking to design and tune the selectivity of bimetallic electrocatalysts for CO2 reduction through valorization of metallurgical waste.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000853941300001 Publication Date 2022-06-28
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 4.5 Times cited 7 Open Access OpenAccess
Notes S.Y and B.M.W. acknowledge support from the EU Framework Programme for Research and Innovation Horizon 2020 (SOCRATES-721385; project website: http://etn-socrates.eu/). W.v.d.S., M.C.F. and B.M.W. acknowledge support from the Strategic UU-TU/e Alliance project 'Joint Centre for Chemergy Research'. S.B. acknowledges support from the European Research Council (ERC Consolidator Grant #815128 REALNANO). S.A. and T.A. acknowledge funding from the University of Antwerp Research fund (BOF). The Beijing Synchrotron Radiation Facility (1W1B, BSRF) is acknowledged for the beamtime. We are grateful to Annelies van der Bok and Bas Salzmann (Condensed Matter and Interfaces, Utrecht University, UU) for the support with the ICP-OES measurements. The authors thank dr. Robin Geitenbeek, Nikos Nikolopoulos, Ioannis Nikolopoulos, Jochem Wijten and Joris Janssens (Inorganic Chemistry and Catalysis, UU) for helpful discussions and technical support. The authors also thank Yuang Piao (Materials Chemistry and Catalysis, UU) for the help in the preparation of the figures of the article. Approved Most recent IF: 4.5
Call Number UA @ admin @ c:irua:190703 Serial 7226
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Author Mei, H.; Xu, W.; Wang, C.; Yuan, H.; Zhang, C.; Ding, L.; Zhang, J.; Deng, C.; Wang, Y.; Peeters, F.M.
Title Terahertz magneto-optical properties of bi- and tri-layer graphene Type A1 Journal article
Year 2018 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat
Volume 30 Issue (down) 17 Pages 175701
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Magneto-optical (MO) properties of bi- and tri-layer graphene are investigated utilizing terahertz time-domain spectroscopy (THz TDS) in the presence of a strong magnetic field at room-temperature. In the Faraday configuration and applying optical polarization measurements, we measure the real and imaginary parts of the longitudinal and transverse MO conductivities of different graphene samples. The obtained experimental data fits very well with the classical MO Drude formula. Thus, we are able to obtain the key sample and material parameters of bi- and tri-layer graphene, such as the electron effective mass, the electronic relaxation time and the electron density. It is found that in high magnetic fields the electronic relaxation time tau for bi- and tri-layer graphene increases with magnetic field B roughly in a form tau similar to B-2. Most importantly, we obtain the electron effective mass for bi- and tri-layer graphene at room-temperature under non-resonant conditions. This work shows how the advanced THz MO techniques can be applied for the investigation into fundamental physics properties of atomically thin 2D electronic systems.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000429329500001 Publication Date 2018-03-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0953-8984 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.649 Times cited 11 Open Access
Notes ; This work was supported by the National Natural Science Foundation of China (11574319, 11304317, 11304272), the Ministry of Science and Technology of China (2011YQ130018), the Center of Science and Technology of Hefei Academy of Science, the Department of Science and Technology of Yunnan Province, and by the Chinese Academy of Sciences. ; Approved Most recent IF: 2.649
Call Number UA @ lucian @ c:irua:150715UA @ admin @ c:irua:150715 Serial 4983
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Author Tan, H.; Egoavil, R.; Béché, A.; Martinez, G.T.; Van Aert, S.; Verbeeck, J.; Van Tendeloo, G.; Rotella, H.; Boullay, P.; Pautrat, A.; Prellier, W.
Title Mapping electronic reconstruction at the metal-insulator interface in LaVO3/SrVO3 heterostructures Type A1 Journal article
Year 2013 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 88 Issue (down) 15 Pages 155123-155126
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract A (LaVO3)6/(SrVO3)(3) superlattice is studied with a combination of sub-A resolved scanning transmission electron microscopy and monochromated electron energy-loss spectroscopy. The V oxidation state is mapped with atomic spatial resolution enabling us to investigate electronic reconstruction at the LaVO3/SrVO3 interfaces. Surprisingly, asymmetric charge distribution is found at adjacent chemically symmetric interfaces. The local structure is proposed and simulated with a double channeling calculation which agrees qualitatively with our experiment. We demonstrate that local strain asymmetry is the likely cause of the electronic asymmetry of the interfaces. The electronic reconstruction at the interfaces extends much further than the chemical composition, varying from 0.5 to 1.2 nm. This distance corresponds to the length of charge transfer previously found in the (LaVO3)./(SrVO3). metal/insulating and the (LaAlO3)./(SrTiO3). insulating/insulating interfaces.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000326087100003 Publication Date 2013-10-21
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 15 Open Access
Notes Hercules; 246791 COUNTATOMS; 278510 VORTEX; 246102 IFOX; 312483 ESTEEM2; FWO; GOA XANES meets ELNES; esteem2jra3 ECASJO; Approved Most recent IF: 3.836; 2013 IF: 3.664
Call Number UA @ lucian @ c:irua:112733UA @ admin @ c:irua:112733 Serial 1944
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Author Huang, S.-Z.; Jin, J.; Cai, Y.; Li, Y.; Tan, H.-Y.; Wang, H.-E.; Van Tendeloo, G.; Su, B.-L.
Title Engineering single crystalline Mn3O4 nano-octahedra with exposed highly active {011} facets for high performance lithium ion batteries Type A1 Journal article
Year 2014 Publication Nanoscale Abbreviated Journal Nanoscale
Volume 6 Issue (down) 12 Pages 6819-6827
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Well shaped single crystalline Mn3O4 nano-octahedra with exposed highly active {011} facets at different particle sizes have been synthesized and used as anode materials for lithium ion batteries. The electrochemical results show that the smallest sized Mn3O4 nano-octahedra show the best cycling performance with a high initial charge capacity of 907 mA h g−1 and a 50th charge capacity of 500 mA h g−1 at a current density of 50 mA g−1 and the best rate capability with a charge capacity of 350 mA h g−1 when cycled at 500 mA g−1. In particular, the nano-octahedra samples demonstrate a much better electrochemical performance in comparison with irregular shaped Mn3O4 nanoparticles. The best electrochemical properties of the smallest Mn3O4 nano-octahedra are ascribed to the lower charge transfer resistance due to the exposed highly active {011} facets, which can facilitate the conversion reaction of Mn3O4 and Li owing to the alternating Mn and O atom layers, resulting in easy formation and decomposition of the amorphous Li2O and the multi-electron reaction. On the other hand, the best electrochemical properties of the smallest Mn3O4 nano-octahedra can also be attributed to the smallest size resulting in the highest specific surface area, which provides maximum contact with the electrolyte and facilitates the rapid Li-ion diffusion at the electrode/electrolyte interface and fast lithium-ion transportation within the particles. The synergy of the exposed {011} facets and the smallest size (and/or the highest surface area) led to the best performance for the Mn3O4 nano-octahedra. Furthermore, HRTEM observations verify the oxidation of MnO to Mn3O4 during the charging process and confirm that the Mn3O4 octahedral structure can still be partly maintained after 50 dischargecharge cycles. The high Li-ion storage capacity and excellent cycling performance suggest that Mn3O4 nano-octahedra with exposed highly active {011} facets could be excellent anode materials for high-performance lithium-ion batteries.
Address
Corporate Author Thesis
Publisher Place of Publication Cambridge Editor
Language Wos 000337143900072 Publication Date 2014-04-09
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2040-3364;2040-3372; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 7.367 Times cited 80 Open Access
Notes Approved Most recent IF: 7.367; 2014 IF: 7.394
Call Number UA @ lucian @ c:irua:117076 Serial 1047
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Author Boullay, P.; David, A.; Sheets, W.C.; Lüders, U.; Prellier, W.; Tan, H.; Verbeeck, J.; Van Tendeloo, G.; Gatel, C.; Vincze, G.; Radi, Z.
Title Microstructure and interface studies of LaVO3/SrVO3 superlattices Type A1 Journal article
Year 2011 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 83 Issue (down) 12 Pages 125403-125403,6
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The structure and interface characteristics of (LaVO3)6m(SrVO3)m superlattices deposited on a (100)-SrTiO3 substrate were studied using transmission electron microscopy (TEM). Cross-section TEM studies revealed that both LaVO3 (LVO) and SrVO3 (SVO) layers are good single-crystal quality and epitaxially grown with respect to the substrate. It is evidenced that LVO layers are made of two orientational variants of a distorted perovskite compatible with bulk LaVO3, while SVO layers suffers from a tetragonal distortion due to the substrate-induced stain. Electron energy loss spectroscopy investigations indicate changes in the fine structure of the V L23 edge, related to a valence change between the LaVO3 and the SrVO3 layers.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000288160300006 Publication Date 2011-03-09
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 26 Open Access
Notes Fwo; Esteem 026019 Approved Most recent IF: 3.836; 2011 IF: 3.691
Call Number UA @ lucian @ c:irua:88648UA @ admin @ c:irua:88648 Serial 2054
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Author Tan, H.; Lebedev, O.I.; McLaughlin, A.C.; Van Tendeloo, G.
Title The superstructure and superconductivity of Ru1222 based RuSr2Gd2-x-yYyCexCu2O10-\delta compounds Type A1 Journal article
Year 2010 Publication Superconductor science and technology Abbreviated Journal Supercond Sci Tech
Volume 23 Issue (down) 11 Pages 115013-115013,8
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract For the first time, the local structure and physical properties of Ru1222 based compounds (RuSr(2)Gd(1.4)Ce(0.6)Cu(2)O(10-delta) and RuSr(2)Gd(1.8-x)Y(0.2)CexCu(2)O(10) (x = 0.90-0.55)) have been investigated and analyzed together on the very same compounds. The Ru1222 superstructure was confirmed by TEM at a local scale and was suggested to have an orthorhombic symmetry with space group Aba2 and lattice parameters a(s) similar or equal to root 2a, b(s) similar or equal to root 2a and c(s) = c. This new Ru1222 superstructure distortion from tetragonal symmetry is proposed to have a positive correlation with the superconductivity variation of these compounds. The more the distortion towards orthorhombic symmetry, the higher the critical superconducting temperature these compounds can achieve. The T(c)(0) of RuSr(2)Gd(1.8-x)Y(0.2)Ce(x)Cu(2)O(10-delta) (x = 0.85-0.55) increases monotonically from 4 to 16 K when x decreases from 0.85 to 0.70, then RuSr(2)Gd(2)Cu(2)O(8) defects emerge and the T(c) decreases with decreasing x. Ru1212 defects are observed to intergrow epitaxially with the Ru1222 structure as lamellas along the c-axis in RuSr(2)Gd(1.4)Ce(0.6)Cu(2)O(10-delta). Although Ru1212 is a superconductor, the intergrowth severely restrains its superconductivity.
Address
Corporate Author Thesis
Publisher Place of Publication Bristol Editor
Language Wos 000284308000013 Publication Date 2010-10-09
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0953-2048;1361-6668; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.878 Times cited 1 Open Access
Notes Fwo; Esteem 026019 Approved Most recent IF: 2.878; 2010 IF: 2.402
Call Number UA @ lucian @ c:irua:95553 Serial 3385
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Author Tan, H.; Turner, S.; Yücelen, E.; Verbeeck, J.; Van Tendeloo, G.
Title 2D atomic mapping of oxidation states in transition metal oxides by scanning transmission electron microscopy and electron energy-loss spectroscopy Type A1 Journal article
Year 2011 Publication Physical review letters Abbreviated Journal Phys Rev Lett
Volume 107 Issue (down) 10 Pages 107602
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Using a combination of high-angle annular dark-field scanning transmission electron microscopy and atomically resolved electron energy-loss spectroscopy in an aberration-corrected transmission electron microscope we demonstrate the possibility of 2D atom by atom valence mapping in the mixed valence compound Mn3O4. The Mn L2,3 energy-loss near-edge structures from Mn2+ and Mn3+ cation sites are similar to those of MnO and Mn2O3 references. Comparison with simulations shows that even though a local interpretation is valid here, intermixing of the inelastic signal plays a significant role. This type of experiment should be applicable to challenging topics in materials science, such as the investigation of charge ordering or single atom column oxidation states in, e.g., dislocations.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000294406600018 Publication Date 2011-09-01
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0031-9007;1079-7114; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 8.462 Times cited 115 Open Access
Notes Esteem 026019; Fwo Approved Most recent IF: 8.462; 2011 IF: 7.370
Call Number UA @ lucian @ c:irua:91265 c:irua:91265 c:irua:91265UA @ admin @ c:irua:91265 Serial 5
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Author Chen, L.-H.; Li, X.-Y.; Tian, G.; Li, Y.; Tan, H.-Y.; Van Tendeloo, G.; Zhu, G.-S.; Qiu, S.-L.; Yang, X.-Y.; Su, B.-L.
Title Multimodal zeolite-beta-based catalysts with a hierarchical, three-level pore structure Type A1 Journal article
Year 2011 Publication Chemsuschem Abbreviated Journal Chemsuschem
Volume 4 Issue (down) 10 Pages 1452-1456
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Hole diggers: The hierarchically structured porous solid-acid catalyst described in this report possess a remarkable pore system, encompassing well-defined macrochannels, interconnected mesopores, intracrystalline mesopores, and tunable zeolite micropores. Importantly, the catalyst exhibits very strong acidity and superior catalytic activity for esterification reactions.
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Corporate Author Thesis
Publisher Place of Publication Weinheim Editor
Language Wos 000296497400009 Publication Date 2011-08-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1864-5631; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 7.226 Times cited 33 Open Access
Notes Iap Approved Most recent IF: 7.226; 2011 IF: 6.827
Call Number UA @ lucian @ c:irua:93675 Serial 2223
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Author Zhou, Y.; Che, F.; Liu, M.; Zou, C.; Liang, Z.; De Luna, P.; Yuan, H.; Li, J.; Wang, Z.; Xie, H.; Li, H.; Chen, P.; Bladt, E.; Quintero-Bermudez, R.; Sham, T.-K.; Bals, S.; Hofkens, J.; Sinton, D.; Chen, G.; Sargent, E.H.
Title Dopant-induced electron localization drives CO2 reduction to C2 hydrocarbons Type A1 Journal article
Year 2018 Publication Nature chemistry Abbreviated Journal Nat Chem
Volume 10 Issue (down) 10 Pages 974-980
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The electrochemical reduction of CO2 to multi-carbon products has attracted much attention because it provides an avenue to the synthesis of value-added carbon-based fuels and feedstocks using renewable electricity. Unfortunately, the efficiency of CO2 conversion to C-2 products remains below that necessary for its implementation at scale. Modifying the local electronic structure of copper with positive valence sites has been predicted to boost conversion to C-2 products. Here, we use boron to tune the ratio of Cu delta+ to Cu-0 active sites and improve both stability and C-2-product generation. Simulations show that the ability to tune the average oxidation state of copper enables control over CO adsorption and dimerization, and makes it possible to implement a preference for the electrosynthesis of C-2 products. We report experimentally a C-2 Faradaic efficiency of 79 +/- 2% on boron-doped copper catalysts and further show that boron doping leads to catalysts that are stable for in excess of similar to 40 hours while electrochemically reducing CO2 to multi-carbon hydrocarbons.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000442395200013 Publication Date 2018-07-13
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1755-4330; 1755-4349 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 25.87 Times cited 700 Open Access OpenAccess
Notes ; This work was supported financially by funding from TOTAL S.A., the Ontario Research Fund: Research Excellence Program, the Natural Sciences and Engineering Research Council of Canada, the CIFAR Bio-Inspired Solar Energy programme, a University of Toronto Connaught grant, the Ministry of Science, Natural Science Foundation of China (21471040, 21271055 and 21501035), the Innovation-Driven Plan in Central South University project (2017CX003), a project from State Key Laboratory of Powder Metallurgy in Central South University, the Thousand Youth Talents Plan of China and Hundred Youth Talents Program of Hunan and the China Scholarship Council programme. This work benefited from the soft X-ray microcharacterization beamline at CLS, sector 20BM at the APS and the Ontario Centre for the Characterisation of Advanced Materials at the University of Toronto. H.Y. acknowledges financial support from the Research Foundation-Flanders (FWO postdoctoral fellowship). C.Z. acknowledges support from the International Academic Exchange Fund for Joint PhD Students from Tianjin University. P.D.L. acknowledges financial support from the Natural Sciences and Engineering Research Council in the form of the Canada Graduate Scholarship-Doctoral award. S.B. and E.B. acknowledge financial support from the European Research Council (ERC Starting Grant # 335078-COLOURATOMS). The authors thank B. Zhang, N. Wang, C. T. Dinh, T. Zhuang, J. Li and Y. Zhao for fruitful discussions, as well as Y. Hu and Q. Xiao from CLS, and Z. Finfrock and M. Ward from APS for their help during the course of study. Computations were performed on the SOSCIP Consortium's Blue Gene/Q computing platform. SOSCIP is funded by the Federal Economic Development Agency of Southern Ontario, the Province of Ontario, IBM Canada, Ontario Centres of Excellence, Mitacs and 15 Ontario academic member institutions. ; ecas_sara Approved Most recent IF: 25.87
Call Number UA @ lucian @ c:irua:153693UA @ admin @ c:irua:153693 Serial 5091
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Author Becker, M.; Guzzinati, G.; Béché, A.; Verbeeck, J.; Batelaan, H.
Title Asymmetry and non-dispersivity in the Aharonov-Bohm effect Type A1 Journal article
Year 2019 Publication Nature communications Abbreviated Journal Nat Commun
Volume 10 Issue (down) 10 Pages 1700
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Decades ago, Aharonov and Bohm showed that electrons are affected by electromagnetic potentials in the absence of forces due to fields. Zeilinger's theorem describes this absence of classical force in quantum terms as the “dispersionless” nature of the Aharonov-Bohm effect. Shelankov predicted the presence of a quantum “force” for the same Aharonov-Bohm physical system as elucidated by Berry. Here, we report an experiment designed to test Shelankov's prediction and we provide a theoretical analysis that is intended to elucidate the relation between Shelankov's prediction and Zeilinger's theorem. The experiment consists of the Aharonov-Bohm physical system; free electrons pass a magnetized nanorod and far-field electron diffraction is observed. The diffraction pattern is asymmetric confirming one of Shelankov's predictions and giving indirect experimental evidence for the presence of a quantum “force”. Our theoretical analysis shows that Zeilinger's theorem and Shelankov's result are both special cases of one theorem.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000464338100011 Publication Date 2019-04-12
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 12 Open Access OpenAccess
Notes ; H.B. would like to thank Michael Berry for bringing the presence of a quantum “force” to our attention. A.B., G.G. and J.V. acknowledge support from the European Research Council under the 7th Framework Program (FP7) ERC Starting Grant 278510 VORTEX. G.G. acknowledges support from the Fonds Wetenschappelijk Onderzoek -Vlaanderen (FWO). M.B. and H.B. acknowledge support by the U.S. National Science Foundation under Grant No. 1602755. ; Approved Most recent IF: 12.124
Call Number UA @ admin @ c:irua:159341 Serial 5241
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