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Author | Conings, B.; Drijkoningen, J.; Gauquelin, N.; Babayigit, A.; D'Haen, J.; D'Olieslaeger, L.; Ethirajan, A.; Verbeeck, J.; Manca, J.; Mosconi, E.; Angelis, F.D.; Boyen, H.G.; | ||||
Title | Intrinsic thermal instability of methylammonium lead trihalide perovskite | Type | A1 Journal article | ||
Year | 2015 | Publication | Laser physics review | Abbreviated Journal | Adv Energy Mater |
Volume | 5 | Issue | 5 | Pages | 1500477 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Organolead halide perovskites currently are the new front-runners as light absorbers in hybrid solar cells, as they combine efficiencies passing already 20% with deposition temperatures below 100 °C and cheap solution-based fabrication routes. Long-term stability remains a major obstacle for application on an industrial scale. Here, it is demonstrated that significant decomposition effects already occur during annealing of a methylammonium lead triiode perovskite at 85 °C even in inert atmosphere thus violating international standards. The observed behavior supports the view of currently used perovskite materials as soft matter systems with low formation energies, thus representing a major bottleneck for their application, especially in countries with high average temperatures. This result can trigger a broader search for new perovskite families with improved thermal stability. | ||||
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Publisher | Place of Publication | S.l. | Editor | ||
Language | Wos | 000359374900005 | Publication Date | 2015-06-03 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1614-6832; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 16.721 | Times cited | 1691 | Open Access | |
Notes | FWO G004413N; GOA Solarpaint | Approved | Most recent IF: 16.721; 2015 IF: 16.146 | ||
Call Number | c:irua:127298UA @ admin @ c:irua:127298 | Serial | 1719 | ||
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Author | Dey, A.; Ye, J.; De, A.; Debroye, E.; Ha, S.K.; Bladt, E.; Kshirsagar, A.S.; Wang, Z.; Yin, J.; Wang, Y.; Quan, L.N.; Yan, F.; Gao, M.; Li, X.; Shamsi, J.; Debnath, T.; Cao, M.; Scheel, M.A.; Kumar, S.; Steele, J.A.; Gerhard, M.; Chouhan, L.; Xu, K.; Wu, X.-gang; Li, Y.; Zhang, Y.; Dutta, A.; Han, C.; Vincon, I.; Rogach, A.L.; Nag, A.; Samanta, A.; Korgel, B.A.; Shih, C.-J.; Gamelin, D.R.; Son, D.H.; Zeng, H.; Zhong, H.; Sun, H.; Demir, H.V.; Scheblykin, I.G.; Mora-Sero, I.; Stolarczyk, J.K.; Zhang, J.Z.; Feldmann, J.; Hofkens, J.; Luther, J.M.; Perez-Prieto, J.; Li, L.; Manna, L.; Bodnarchuk, M., I; Kovalenko, M., V; Roeffaers, M.B.J.; Pradhan, N.; Mohammed, O.F.; Bakr, O.M.; Yang, P.; Muller-Buschbaum, P.; Kamat, P., V; Bao, Q.; Zhang, Q.; Krahne, R.; Galian, R.E.; Stranks, S.D.; Bals, S.; Biju, V.; Tisdale, W.A.; Yan, Y.; Hoye, R.L.Z.; Polavarapu, L. | ||||
Title | State of the art and prospects for Halide Perovskite Nanocrystals | Type | A1 Journal article | ||
Year | 2021 | Publication | Acs Nano | Abbreviated Journal | Acs Nano |
Volume | 15 | Issue | 7 | Pages | 10775-10981 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Metal-halide perovskites have rapidly emerged as one of the most promising materials of the 21st century, with many exciting properties and great potential for a broad range of applications, from photovoltaics to optoelectronics and photocatalysis. The ease with which metal-halide perovskites can be synthesized in the form of brightly luminescent colloidal nanocrystals, as well as their tunable and intriguing optical and electronic properties, has attracted researchers from different disciplines of science and technology. In the last few years, there has been a significant progress in the shape-controlled synthesis of perovskite nanocrystals and understanding of their properties and applications. In this comprehensive review, researchers having expertise in different fields (chemistry, physics, and device engineering) of metal-halide perovskite nanocrystals have joined together to provide a state of the art overview and future prospects of metal-halide perovskite nanocrystal research. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000679406500006 | Publication Date | 2021-06-17 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1936-0851 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 13.942 | Times cited | 538 | Open Access | OpenAccess |
Notes | E.D. and J.H. acknowledge financial support from the Research FoundationFlanders (FWO Grant Nos. S002019N, G.0B39.15, G.0B49.15, G.0962.13, G098319N, and ZW15_09-GOH6316), the Research Foundation Flanders postdoctoral fellowships to J.A.S. and E.D. (FWO Grant Nos. 12Y7218N and 12O3719N, respectively), | Approved | Most recent IF: 13.942 | ||
Call Number | UA @ admin @ c:irua:180553 | Serial | 6846 | ||
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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 | 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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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 | Liao, Z.; Huijben, M.; Zhong, Z.; Gauquelin, N.; Macke, S.; Green, R.J.; Van Aert, S.; Verbeeck, J.; Van Tendeloo, G.; Held, K.; Sawatzky, G.A.; Koster, G.; Rijnders, G. | ||||
Title | Controlled lateral anisotropy in correlated manganite heterostructures by interface-engineered oxygen octahedral coupling | Type | A1 Journal article | ||
Year | 2016 | Publication | Nature materials | Abbreviated Journal | Nat Mater |
Volume | 15 | Issue | 15 | Pages | 425-431 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Controlled in-plane rotation of the magnetic easy axis in manganite heterostructures by tailoring the interface oxygen network could allow the development of correlated oxide-based magnetic tunnelling junctions with non-collinear magnetization, with possible practical applications as miniaturized high-switching-speed magnetic random access memory (MRAM) devices. Here, we demonstrate how to manipulate magnetic and electronic anisotropic properties in manganite heterostructures by engineering the oxygen network on the unit-cell level. The strong oxygen octahedral coupling is found to transfer the octahedral rotation, present in the NdGaO3 (NGO) substrate, to the La2/3Sr1/3MnO3 (LSMO) film in the interface region. This causes an unexpected realignment of the magnetic easy axis along the short axis of the LSMO unit cell as well as the presence of a giant anisotropic transport in these ultrathin LSMO films. As a result we possess control of the lateral magnetic and electronic anisotropies by atomic-scale design of the oxygen octahedral rotation. | ||||
Address | MESA+ Institute for Nanotechnology, University of Twente, PO Box 217, 7500 AE Enschede, The Netherlands | ||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | English | Wos | 000372591700017 | Publication Date | 2016-03-07 |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1476-1122 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 39.737 | Times cited | 273 | Open Access | |
Notes | We would like to acknowledge Dr. Evert Houwman for stimulated discussion. M.H., G.K. and G.R. acknowledge funding from DESCO program of the Dutch Foundation for Fundamental Research on Matter (FOM) with financial support from the Netherlands Organization for Scientific Research (NWO). This work was funded by the European Union Council under the 7th Framework Program (FP7) grant nr NMP3-LA-2010- 246102 IFOX. J.V. and S.V.A. acknowledges funding from FWO project G.0044.13N and G. 0368.15N. The Qu-Ant-EM microscope was partly funded by the Hercules fund from the Flemish Government. N.G. acknowledges funding from the European Research Council under the 7th Framework Program (FP7), ERC Starting Grant 278510 VORTEX. N.G., S.V.A., J.V. and G.V.T. acknowledge financial support from the European Union under the Seventh Framework Program under a contract for an Integrated Infrastructure Initiative (Reference No. 312483-ESTEEM2). The Canadian work was supported by NSERC and the Max Planck-UBC Centre for Quantum Materials. Some experiments for this work were performed at the Canadian Light Source, which is funded by the Canada Foundation for Innovation, NSERC, the National Research Council of Canada, the Canadian Institutes of Health Research, the Government of Saskatchewan, Western Economic Diversification Canada, and the University of Saskatchewan. Z.Z. acknowledges funding from the SFB ViCoM (Austrian Science Fund project ID F4103- N13), and Calculations have been done on the Vienna Scientific Cluster (VSC).; esteem2jra2; esteem2jra3 ECASJO_; | Approved | Most recent IF: 39.737 | ||
Call Number | c:irua:133190 c:irua:133190UA @ admin @ c:irua:133190 | Serial | 4041 | ||
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Author | Chen, Y.Z.; Trier, F.; Wijnands, T.; Green, R.J.; Gauquelin, N.; Egoavil, R.; Christensen, D.V.; Koster, G.; Huijben, M.; Bovet, N.; Macke, S.; He, F.; Sutarto, R.; Andersen, N.H.; Sulpizio, J.A.; Honig, M.; Prawiroatmodjo, G.E.D.K.; Jespersen, T.S.; Linderoth, S.; Ilani, S.; Verbeeck, J.; Van Tendeloo, G.; Rijnders, G.; Sawatzky, G.A.; Pryds, N. | ||||
Title | Extreme mobility enhancement of two-dimensional electron gases at oxide interfaces by charge-transfer-induced modulation doping | Type | A1 Journal article | ||
Year | 2015 | Publication | Nature materials | Abbreviated Journal | Nat Mater |
Volume | 14 | Issue | 14 | Pages | 801-806 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Two-dimensional electron gases (2DEGs) formed at the interface of insulating complex oxides promise the development of all-oxide electronic devices. These 2DEGs involve many-body interactions that give rise to a variety of physical phenomena such as superconductivity, magnetism, tunable metalinsulator transitions and phase separation. Increasing the mobility of the 2DEG, however, remains a major challenge. Here, we show that the electron mobility is enhanced by more than two orders of magnitude by inserting a single-unit-cell insulating layer of polar La1−xSrxMnO3 (x = 0, 1/8, and 1/3) at the interface between disordered LaAlO3 and crystalline SrTiO3 produced at room temperature. Resonant X-ray spectroscopy and transmission electron microscopy show that the manganite layer undergoes unambiguous electronic reconstruction, leading to modulation doping of such atomically engineered complex oxide heterointerfaces. At low temperatures, the modulation-doped 2DEG exhibits Shubnikovde Haas oscillations and fingerprints of the quantum Hall effect, demonstrating unprecedented high mobility and low electron density. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | London | Editor | ||
Language | Wos | 000358530100022 | Publication Date | 2015-06-01 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1476-1122;1476-4660; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 39.737 | Times cited | 170 | Open Access | |
Notes | 246102 IFOX; 246791 COUNTATOMS; 278510 VORTEX; Hercules; 312483 ESTEEM2; FWO G004413N; esteem2jra3 ECASJO; | Approved | Most recent IF: 39.737; 2015 IF: 36.503 | ||
Call Number | c:irua:127184 c:irua:127184UA @ admin @ c:irua:127184 | Serial | 1163 | ||
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Author | Gou, H.; Dubrovinskaia, N.; Bykova, E.; Tsirlin, A.A.; Kasinathan, D.; Schnelle, W.; Richter, A.; Merlini, M.; Hanfland, M.; Abakumov, A.M.; Batuk, D.; Van Tendeloo, G.; Nakajima, Y.; Kolmogorov, A.N.; Dubrovinsky, L.; | ||||
Title | Discovery of a superhard iron tetraboride superconductor | Type | A1 Journal article | ||
Year | 2013 | Publication | Physical review letters | Abbreviated Journal | Phys Rev Lett |
Volume | 111 | Issue | 15 | Pages | 157002-157005 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Single crystals of novel orthorhombic (space group Pnnm) iron tetraboride FeB4 were synthesized at pressures above 8 GPa and high temperatures. Magnetic susceptibility and heat capacity measurements demonstrate bulk superconductivity below 2.9 K. The putative isotope effect on the superconducting critical temperature and the analysis of specific heat data indicate that the superconductivity in FeB4 is likely phonon mediated, which is rare for Fe-based superconductors. The discovered iron tetraboride is highly incompressible and has the nanoindentation hardness of 62(5) GPa; thus, it opens a new class of highly desirable materials combining advanced mechanical properties and superconductivity. | ||||
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Publisher | Place of Publication | New York, N.Y. | Editor | ||
Language | Wos | 000325371500011 | Publication Date | 2013-10-09 | |
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 | 127 | Open Access | |
Notes | Countatoms | Approved | Most recent IF: 8.462; 2013 IF: 7.728 | ||
Call Number | UA @ lucian @ c:irua:110820 | Serial | 729 | ||
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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 | 6 | Issue | Pages | 159-168 | |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
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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 | Conings, B.; Babayigit, A.; Klug, M. T.; Bai, S.; Gauquelin, N.; Sakai, N.; Wang, J. T.-W.; Verbeeck, J.; Boyen, H.-G. | ||||
Title | A Universal Deposition Protocol for Planar Heterojunction Solar Cells with High Efficiency Based on Hybrid Lead Halide Perovskite Families | Type | A1 Journal article | ||
Year | 2016 | Publication | Advanced materials | Abbreviated Journal | Adv Mater |
Volume | 28 | Issue | 28 | Pages | 10701-10709 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | A robust and expedient gas quenching method is developed for the solution deposition of hybrid perovskite thin films. The method offers a reliable standard practice for the fabrication of a non-exhaustive variety of perovskites exhibiting excellent film morphology and commensurate high performance in both regular and inverted structured solar cell architectures. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000392728200014 | Publication Date | 2016-10-17 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1521-4095 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 19.791 | Times cited | 95 | Open Access | |
Notes | This work was financially supported by BOF (Hasselt University) and the Research Fund Flanders (FWO). B.C. is a postdoctoral research fellow of the FWO. A.B. is financially supported by Imec and FWO. M.T.K. acknowledges funding from the EPSRC project EP/M024881/1 “Organic-inorganic Perovskite Hybrid Tandem Solar Cells”. S.B. is a VINNMER Fellow and Marie Skłodowska-Curie Fellow. J.V. and N.G. acknowledge funding from GOA project “Solarpaint” of the University of Antwerp and FWO project G.0044.13N “Charge ordering”. The Qu-Ant-EM microscope used for this study was partly funded by the Hercules fund from the Flemish Government. N.G. acknowledges funding from the European Research Council under the 7th Framework Program (FP7), ERC Starting Grant 278510 VORTEX. The authors thank Johnny Baccus and Jan Mertens for technical support.; ECASJO_; | Approved | Most recent IF: 19.791; 2016 IF: NA | ||
Call Number | EMAT @ emat @ c:irua:138597 | Serial | 4318 | ||
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Author | Lin, K.; Pescarmona, P.P.; Houthoofd, K.; Liang, D.; Van Tendeloo, G.; Jacobs, P.A. | ||||
Title | Direct room-temperature synthesis of methyl-functionalized Ti-MCM-41 nanoparticles and their catalytic performance in epoxidation | Type | A1 Journal article | ||
Year | 2009 | Publication | Journal of catalysis | Abbreviated Journal | J Catal |
Volume | 263 | Issue | 1 | Pages | 75-82 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Methyl-functionalized Ti-MCM-41 nanoparticles with a size of 80 to 160 nm (Me-Ti-MCM-41 NP) were directly prepared via a dilute solution route by the co-condensation of tetraethoxysilane and methylalkoxysilanes in sodium hydroxide medium at room temperature. The characterization results showed the existence of ordered hexagonal mesoporous structure and tetrahedral Ti species in the nanoparticles. In the epoxidation of cyclohexene with tert-butyl hydroperoxide and aqueous H2O2, Me-Ti-MCM-41 NP samples displayed higher turnover frequencies (TOFs) for cyclohexene and initial reaction rates compared to Ti-MCM-41 and methyl-functionalized Ti-MCM-41 with normal particle size and to non-functionalized Ti-MCM-41 nanoparticles. Simultaneously, a higher selectivity for cyclohexene epoxide was observed in the case of aqueous H2O2, suggesting that the hydrolysis of cyclohexene epoxide with water is reduced on Me-Ti-MCM-41 NP samples. The improved catalytic behavior of Me-Ti-MCM-41 NP is discussed both in terms of the nanosize and methylation of the surface of the catalyst particles. The regeneration of Me-Ti-MCM-41 NP with tert-butyl hydroperoxide solution was evaluated via washing and calcination approaches. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | San Diego, Calif. | Editor | ||
Language | Wos | 000265000800008 | Publication Date | 2009-02-14 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0021-9517; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 6.844 | Times cited | 89 | Open Access | |
Notes | Iwt; Iap; Goa | Approved | Most recent IF: 6.844; 2009 IF: 5.288 | ||
Call Number | UA @ lucian @ c:irua:76395 | Serial | 720 | ||
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Author | Ovsyannikov, S.V.; Abakumov, A.M.; Tsirlin, A.A.; Schnelle, W.; Egoavil, R.; Verbeeck, J.; Van Tendeloo, G.; Glazyrin, K.V.; Hanfland, M.; Dubrovinsky, L. | ||||
Title | Perovskite-like Mn2O3 : a path to new manganites | Type | A1 Journal article | ||
Year | 2013 | Publication | Angewandte Chemie | Abbreviated Journal | Angew Chem Int Edit |
Volume | 52 | Issue | 5 | Pages | 1494-1498 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Korund-artiges ε-Mn2O3 und Perowskit-artiges ζ-Mn2O3, zwei neue Phasen von Mn2O3, wurden unter hohen Drücken bei hohen Temperaturen synthetisiert. Die Manganatome können vollständig die A- und B-Positionen der Perowskitstruktur besetzen. ζ-Mn2O3 (siehe Bild, A-Positionsordnung) enthält Mn in den drei Oxidationsstufen +II, +III und +IV. | ||||
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Publisher | Place of Publication | Weinheim | Editor | ||
Language | Wos | 000313913300027 | Publication Date | 2012-12-22 | |
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Series Volume | Series Issue | Edition | |||
ISSN | 1433-7851; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 11.994 | Times cited | 84 | Open Access | |
Notes | This work was supported by the DFG (project OV-110/1-1), Alexander von Humboldt foundation, European Union Council (FP7)-Grant no. 246102 IFOX, European Research Council (FP7)-ERC Starting Grant no. 278510 VORTEX and ERC Grant no. 246791-COUNTATOMS, and Hercules fund from the Flemish Government. ECASJO_; | Approved | Most recent IF: 11.994; 2013 IF: 11.336 | ||
Call Number | UA @ lucian @ c:irua:108765UA @ admin @ c:irua:108765 | Serial | 2573 | ||
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Author | Groenendijk, D.J.; Autieri, C.; Girovsky, J.; Martinez-Velarte, M.C.; Manca, N.; Mattoni, G.; Monteiro, A.M.R.V.L.; Gauquelin, N.; Verbeeck, J.; Otte, A.F.; Gabay, M.; Picozzi, S.; Caviglia, A.D. | ||||
Title | Spin-orbit semimetal SrIrO3 in the two-dimensional limit | Type | A1 Journal article | ||
Year | 2017 | Publication | Physical review letters | Abbreviated Journal | Phys Rev Lett |
Volume | 119 | Issue | 25 | Pages | 256403 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | <script type='text/javascript'>document.write(unpmarked('We investigate the thickness-dependent electronic properties of ultrathin SrIrO3 and discover a transition from a semimetallic to a correlated insulating state below 4 unit cells. Low-temperature magnetoconductance measurements show that spin fluctuations in the semimetallic state are significantly enhanced while approaching the transition point. The electronic properties are further studied by scanning tunneling spectroscopy, showing that 4 unit cell SrIrO(3)d is on the verge of a gap opening. Our density functional theory calculations reproduce the critical thickness of the transition and show that the opening of a gap in ultrathin SrIrO3 requires antiferromagnetic order.')); | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | New York, N.Y. | Editor | ||
Language | Wos | 000418619100014 | Publication Date | 2017-12-22 | |
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Series Volume | Series Issue | Edition | |||
ISSN | 0031-9007 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 8.462 | Times cited | 79 | Open Access | OpenAccess |
Notes | ; This work was supported by The Netherlands Organisation for Scientific Research (NWO/OCW) as part of the Frontiers of Nanoscience program (NanoFront), by the Dutch Foundation for Fundamental Research on Matter (FOM), and by the European Research Council under the European Union's H2020 programme/ERC Grant Agreement No. [677458]. The authors thank R. Claessen, P. Schutz, D. Di Sante, G. Sangiovanni, and A. Santander Syro for useful discussions. M. G. gratefully acknowledges support from the French National Research Agency (ANR) (Project LACUNES No. ANR-13-BS04-0006-01). C. A. and S. P. acknowledge financial support from Fondazione Cariplo via the project Magister (Project No. 2013-0726) and from CNR-SPIN via the Seed Project “CAMEO”. N. G. and J. V. acknowledge support from the GOA project “Solarpaint” of the University of Antwerp. The Qu-AntEM microscope was partly funded by the Hercules fund from the Flemish Government. ; | Approved | Most recent IF: 8.462 | ||
Call Number | UA @ lucian @ c:irua:148510 | Serial | 4897 | ||
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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 | 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 | 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 | 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. | ||||
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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 | Lueangchaichaweng, W.; Brooks, N.R.; Fiorilli, S.; Gobechiya, E.; Lin, K.; Li, L.; Parres-Esclapez, S.; Javon, E.; Bals, S.; Van Tendeloo, G.; Martens, J.A.; Kirschhock, C.E.A.; Jacobs, P.A.; Pescarmona, P.P.; | ||||
Title | Gallium oxide nanorods : novel, template-free synthesis and high catalytic activity in epoxidation reactions | Type | A1 Journal article | ||
Year | 2014 | Publication | Angewandte Chemie: international edition in English | Abbreviated Journal | Angew Chem Int Edit |
Volume | 53 | Issue | 6 | Pages | 1585-1589 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Gallium oxide nanorods with unprecedented small dimensions (20-80nm length and 3-5nm width) were prepared using a novel, template-free synthesis method. This nanomaterial is an excellent heterogeneous catalyst for the sustainable epoxidation of alkenes with H2O2, rivaling the industrial benchmark microporous titanosilicate TS-1 with linear alkenes and being much superior with bulkier substrates. A thorough characterization study elucidated the correlation between the physicochemical properties of the gallium oxide nanorods and their catalytic performance, and underlined the importance of the nanorod morphology for generating a material with high specific surface area and a high number of accessible acid sites. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Weinheim | Editor | ||
Language | Wos | 000330558400021 | Publication Date | 2014-01-22 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1433-7851; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 11.994 | Times cited | 61 | Open Access | OpenAccess |
Notes | START 1; Methusalem; Prodex; IAP-PAI; and the ERC (grant number 24691-COUNTATOMS and grant number 335078-COLOURATOM) projects; ECAS_Sara; (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); | Approved | Most recent IF: 11.994; 2014 IF: 11.261 | ||
Call Number | UA @ lucian @ c:irua:115726 | Serial | 1314 | ||
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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 | 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 | Belik, A.A.; Abakumov, A.M.; Tsirlin, A.A.; Hadermann, J.; Kim, J.; Van Tendeloo, G.; Takayama-Muromachi, E. | ||||
Title | Article Structure and magnetic properties of BiFe0.75Mn0.25O3 perovskite prepared at ambient and high pressure | Type | A1 Journal article | ||
Year | 2011 | Publication | Chemistry of materials | Abbreviated Journal | Chem Mater |
Volume | 23 | Issue | 20 | Pages | 4505-4514 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Solid solutions of BiFe1xMnxO3 (0.0 ≤ x ≤ 0.4) were prepared at ambient pressure and at 6 GPa. The ambient-pressure (AP) phases crystallize in space group R3c similarly to BiFeO3. The high-pressure (HP) phases crystallize in space group R3c for x = 0.05 and in space group Pnma for 0.15 ≤ x ≤ 0.4. The structure of HP-BiFe0.75Mn0.25O3 was investigated using synchrotron X-ray powder diffraction, electron diffraction, and transmission electron microscopy. HP-BiFe0.75Mn0.25O3 has a PbZrO3-related √2ap × 4ap × 2√2ap (ap is the parameter of the cubic perovskite subcell) superstructure with a = 5.60125(9) Å, b = 15.6610(2) Å, and c = 11.2515(2) Å similar to that of Bi0.82La0.18FeO3. A remarkable feature of this structure is the unconventional octahedral tilt system, with the primary ab0a tilt superimposed on pairwise clockwise and counterclockwise rotations around the b-axis according to the oioi sequence (o stands for out-of-phase tilt, and i stands for in-phase tilt). The (FeMn)O6 octahedra are distorted, with one longer metaloxygen bond (2.222.23 Å) that can be attributed to a compensation for covalent BiO bonding. Such bonding results in the localization of the lone electron pair on Bi3+ cations, as confirmed by electron localization function analysis. The relationship between HP-BiFe0.75Mn0.25O3 and antiferroelectric structures of PbZrO3 and NaNbO3 is discussed. On heating in air, HP-BiFe0.75Mn0.25O3 irreversibly transforms to AP-BiFe0.75Mn0.25O3 starting from about 600 K. Both AP and HP phases undergo an antiferromagnetic ordering at TN ≈ 485 and 520 K, respectively, and develop a weak net magnetic moment at low temperatures. Additionally, ceramic samples of AP-BiFe0.75Mn0.25O3 show a peculiar phenomenon of magnetization reversal. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Washington, D.C. | Editor | ||
Language | Wos | 000295897400015 | Publication Date | 2011-09-29 | |
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 | 57 | Open Access | |
Notes | Approved | Most recent IF: 9.466; 2011 IF: 7.286 | |||
Call Number | UA @ lucian @ c:irua:93581 | Serial | 151 | ||
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Author | Stambula, S.; Gauquelin, N.; Bugnet, M.; Gorantla, S.; Turner, S.; Sun, S.; Liu, J.; Zhang, G.; Sun, X.; Botton, G.A. | ||||
Title | Chemical structure of nitrogen-doped graphene with single platinum atoms and atomic clusters as a platform for the PEMFC electrode | Type | A1 Journal article | ||
Year | 2014 | Publication | The journal of physical chemistry: C : nanomaterials and interfaces | Abbreviated Journal | J Phys Chem C |
Volume | 118 | Issue | 8 | Pages | 3890-3900 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | A platform for producing stabilized Pt atoms and clusters through the combination of an N-doped graphene support and atomic layer deposition (ALD) for the Pt catalysts was investigated using transmission electron microscopy (TEM) and scanning transmission electron microscopy (STEM). It was determined, using imaging and spectroscopy techniques, that a wide range of N-dopant types entered the graphene lattice through covalent bonds without largely damaging its structure. Additionally and most notably, Pt atoms and atomic clusters formed in the absence of nanoparticles. This work provides a new strategy for experimentally producing stable atomic and subnanometer cluster catalysts, which can greatly assist the proton exchange membrane fuel cell (PEMFC) development by producing the ultimate surface area to volume ratio catalyst. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Washington, D.C. | Editor | ||
Language | Wos | 000332188100004 | Publication Date | 2014-02-12 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1932-7447;1932-7455; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.536 | Times cited | 57 | Open Access | |
Notes | Fwo | Approved | Most recent IF: 4.536; 2014 IF: 4.772 | ||
Call Number | UA @ lucian @ c:irua:115571 | Serial | 352 | ||
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Author | Liao, Z.; Gauquelin, N.; Green, R.J.; Macke, S.; Gonnissen, J.; Thomas, S.; Zhong, Z.; Li, L.; Si, L.; Van Aert, S.; Hansmann, P.; Held, K.; Xia, J.; Verbeeck, J.; Van Tendeloo, G.; Sawatzky, G.A.; Koster, G.; Huijben, M.; Rijnders, G. | ||||
Title | Thickness dependent properties in oxide heterostructures driven by structurally induced metal-oxygen hybridization variations | Type | A1 Journal article | ||
Year | 2017 | Publication | Advanced functional materials | Abbreviated Journal | Adv Funct Mater |
Volume | 27 | Issue | 17 | Pages | 1606717 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Thickness-driven electronic phase transitions are broadly observed in different types of functional perovskite heterostructures. However, uncertainty remains whether these effects are solely due to spatial confinement, broken symmetry, or rather to a change of structure with varying film thickness. Here, this study presents direct evidence for the relaxation of oxygen-2p and Mn-3d orbital (p-d) hybridization coupled to the layer-dependent octahedral tilts within a La2/3Sr1/3MnO3 film driven by interfacial octahedral coupling. An enhanced Curie temperature is achieved by reducing the octahedral tilting via interface structure engineering. Atomically resolved lattice, electronic, and magnetic structures together with X-ray absorption spectroscopy demonstrate the central role of thickness-dependent p-d hybridization in the widely observed dimensionality effects present in correlated oxide heterostructures. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000400449200011 | Publication Date | 2017-03-15 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1616-301x | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 12.124 | Times cited | 55 | Open Access | |
Notes | M.H., G.K., and G.R. acknowledge funding from DESCO program of the Dutch Foundation for Fundamental Research on Matter (FOM) with financial support from the Netherlands Organization for Scientific Research (NWO). This work was funded by the European Union Council under the 7th Framework Program (FP7) Grant No. NMP3-LA-2010-246102 IFOX. J.V. and S.V.A. acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (Grant Nos. G.0044.13N, G.0374.13N, G.0368.15N, and G.0369.15N). The Qu-Ant-EM microscope was partly funded by the Hercules fund from the Flemish Government. N.G. acknowledges funding from the European Research Council under the 7th Framework Program (FP7), ERC Starting Grant No. 278510 VORTEX. N.G., J.G., S.V.A., and J.V. acknowledge financial support from the European Union under the Seventh Framework Program under a contract for an Integrated Infrastructure Initiative (Reference No. 312483-ESTEEM2). The Canadian work was supported by NSERC and the Max Planck-UBC Centre for Quantum Materials. Some experiments for this work were performed at the Canadian Light Source, which was funded by the Canada Foundation for Innovation, NSERC, the National Research Council of Canada, the Canadian Institutes of Health Research, the Government of Saskatchewan, Western Economic Diversification Canada, and the University of Saskatchewan. | Approved | Most recent IF: 12.124 | ||
Call Number | UA @ admin @ c:irua:152640 | Serial | 5367 | ||
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Author | Morozov, V.A.; Lazoryak, B.I.; Shmurak, S.Z.; Kiselev, A.P.; Lebedev, O.I.; Gauquelin, N.; Verbeeck, J.; Hadermann, J.; Van Tendeloo, G. | ||||
Title | Influence of the structure on the properties of NaxEuy(MoO4)z red phosphors | Type | A1 Journal article | ||
Year | 2014 | Publication | Chemistry of materials | Abbreviated Journal | Chem Mater |
Volume | 26 | Issue | 10 | Pages | 3238-3248 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Scheelite related compounds (A',A '')(n)[(B',B '')O-4](m) with B', B '' = W and/or Mo are promising new materials for red phosphors in pc-WLEDs (phosphor-converted white-light-emitting-diode) and solid-state lasers. Cation substitution in CaMoO4 of Ca2+ by the combination of Na+ and Eu3+, with the creation of A cation vacancies, has been investigated as a factor for controlling the scheelite-type structure and the luminescent properties. Na5Eu(MoO4)(4) and NaxEu(2-x)/33+square(2-x)/3MoO4 (0.138 <= x <= 0.5) phases with a scheelite-type structure were synthesized by the solid state method; their structural characteristics were investigated using transmission electron microscopy. Contrary to powder synchrotron X-ray diffraction before, the study by electron diffraction and high resolution transmission electron microscopy in this paper revealed that Na0.286Eu0.571MoO4 has a (3 + 2)D incommensurately modulated structure and that (3 + 2)D incommensurately modulated domains are present in Na0.200Eu0.600MoO4. It also confirmed the (3 + 1)D incommensurately modulated character of Na(0.138)Eu(0.621)Mo04. The luminescent properties of all phases under near-ultraviolet (n-UV) light have been investigated. The excitation spectra of these phosphors show the strongest absorption at about 395 nm, which matches well with the commercially available n-UV-emitting GaN-based LED chip. The emission spectra indicate an intense red emission due to the D-5(0) -> F-7(2) transition of Eu3+, with local minima in the intensity at Na0.286Eu0.571MoO4 and Na0.200Eu0.600MoO4 for similar to 613 nm and similar to 616 nm bands. The phosphor Na5Eu(MoO4)(4) shows the brightest red light emission among the phosphors in the Na2MoO4-Eu2/3MoO4 system and the maximum luminescence intensity of Na5Eu(MoO4)(4) (lambda(ex) = 395 nm) in the D-5(0) -> F-7(2) transition region is close to that of the commercially used red phosphor YVO4:Eu3+ (lambda(ex) = 326 nm). Electron energy loss spectroscopy measurements revealed the influence of the structure and Na/Eu cation distribution on the number and positions of bands in the UV-optical-infrared regions of the EELS spectrum. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000336637000028 | Publication Date | 2014-05-01 | |
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 | 53 | Open Access | |
Notes | Fwo G039211n; Fwo G004413n; 278510 Vortex ECASJO_; | Approved | Most recent IF: 9.466; 2014 IF: 8.354 | ||
Call Number | UA @ lucian @ c:irua:117765UA @ admin @ c:irua:117765 | Serial | 1652 | ||
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Author | Rouvière, J.-L.; Béché, A.; Martin, Y.; Denneulin, T.; Cooper, D. | ||||
Title | Improved strain precision with high spatial resolution using nanobeam precession electron diffraction | Type | A1 Journal article | ||
Year | 2013 | Publication | Applied physics letters | Abbreviated Journal | Appl Phys Lett |
Volume | 103 | Issue | Pages | 241913 | |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | NanoBeam Electron Diffraction is a simple and efficient technique to measure strain in nanostructures. Here, we show that improved results can be obtained by precessing the electron beam while maintaining a few nanometer probe size, i.e., by doing Nanobeam Precession Electron Diffraction (N-PED). The precession of the beam makes the diffraction spots more uniform and numerous, making N-PED more robust and precise. In N-PED, smaller probe size and better precision are achieved by having diffraction disks instead of diffraction dots. Precision in the strain measurement better than 2 × 10−4 is obtained with a probe size approaching 1 nm in diameter. | ||||
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Corporate Author | Thesis | ||||
Publisher | American Institute of Physics | Place of Publication | New York, N.Y. | Editor | |
Language | Wos | 000328706500031 | Publication Date | 2013-12-14 | |
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 | 53 | Open Access | |
Notes | Approved | Most recent IF: 3.411; 2013 IF: 3.515 | |||
Call Number | UA @ lucian @ c:irua:136442 | Serial | 4502 | ||
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Author | Griffin, E.; Mogg, L.; Hao, G.-P.; Kalon, G.; Bacaksiz, C.; Lopez-Polin, G.; Zhou, T.Y.; Guarochico, V.; Cai, J.; Neumann, C.; Winter, A.; Mohn, M.; Lee, J.H.; Lin, J.; Kaiser, U.; Grigorieva, I., V; Suenaga, K.; Ozyilmaz, B.; Cheng, H.-M.; Ren, W.; Turchanin, A.; Peeters, F.M.; Geim, A.K.; Lozada-Hidalgo, M. | ||||
Title | Proton and Li-Ion permeation through graphene with eight-atom-ring defects | Type | A1 Journal article | ||
Year | 2020 | Publication | Acs Nano | Abbreviated Journal | Acs Nano |
Volume | 14 | Issue | 6 | Pages | 7280-7286 |
Keywords | A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) | ||||
Abstract | Defect-free graphene is impermeable to gases and liquids but highly permeable to thermal protons. Atomic-scale defects such as vacancies, grain boundaries, and Stone-Wales defects are predicted to enhance graphene's proton permeability and may even allow small ions through, whereas larger species such as gas molecules should remain blocked. These expectations have so far remained untested in experiment. Here, we show that atomically thin carbon films with a high density of atomic-scale defects continue blocking all molecular transport, but their proton permeability becomes similar to 1000 times higher than that of defect-free graphene. Lithium ions can also permeate through such disordered graphene. The enhanced proton and ion permeability is attributed to a high density of eight-carbon-atom rings. The latter pose approximately twice lower energy barriers for incoming protons compared to that of the six-atom rings of graphene and a relatively low barrier of similar to 0.6 eV for Li ions. Our findings suggest that disordered graphene could be of interest as membranes and protective barriers in various Li-ion and hydrogen technologies. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000543744100086 | Publication Date | 2020-05-19 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1936-0851 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 17.1 | Times cited | 53 | Open Access | |
Notes | ; The work was supported by the Lloyd's Register Foundation, EPSRC-EP/N010345/1, the European Research Council, the Graphene Flagship, the Deutsche Forschungsgemeinschaft project TRR 234 “CataLight” (Project B7, Grant No. 364549901), and the research infrastructure Grant No. INST 275/25 7-1 FUGG. E.G. and L.M. acknowledge the EPSRC NowNANO programme for funding. ; | Approved | Most recent IF: 17.1; 2020 IF: 13.942 | ||
Call Number | UA @ admin @ c:irua:170708 | Serial | 6586 | ||
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Author | Lin, K.; Pescarmona, P.P.; Vandepitte, H.; Liang, D.; Van Tendeloo, G.; Jacobs, P.A. | ||||
Title | Synthesis and catalytic activity of Ti-MCM-41 nanoparticles with highly active titanium sites | Type | A1 Journal article | ||
Year | 2008 | Publication | Journal of catalysis | Abbreviated Journal | J Catal |
Volume | 254 | Issue | 1 | Pages | 64-70 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Ti-MCM-41 nanoparticles 80-160 nm in diameter (Ti-MCM-41 NP) were successfully prepared by a dilute solution route in sodium hydroxide medium at ambient temperature. Ti-MCM-41 NP were characterized by X-ray diffraction, nitrogen adsorption/desorption isotherms, SEM, TEM. FT-IR, and UV-vis spectroscopy. The characterization results showed the existence of highly ordered hexagonal mesoporous structure and tetrahedral Ti species in Ti-MCM-41 NP. In the epoxidation of cyclohexene with aqueous H2O2, Ti-MCM-41 NP displayed higher conversion and initial reaction rate than a Ti-MCM-41 sample with normal particle size (Ti-MCM-41 LP). Diffusion of the reactants was accelerated and the accessibility to the catalytic Ti species was enhanced in the shorter channels in Ti-MCM-41 NP samples. Ti-MCM-41 NP showed much higher selectivity for cyclohexene oxide compared with Ti-MCM-41 LP, suggesting reduced hydrolysis of cyclohexene oxide with water in the former case. The increased selectivity for cyclohexene oxide can be attributed to the lower concentration of residual surface silanols in Ti-MCM-41 NP and the shorter residence time of epoxide in the shorter mesoporous channels. Ti-MCM-41 NP also appears to be a suitable catalyst in the epoxidation of a bulky substrate, like cholesterol, with tert-butyl hydroperoxide. (c) 2007 Elsevier Inc. All rights reserved. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | San Diego, Calif. | Editor | ||
Language | Wos | 000253646100006 | Publication Date | 2008-01-30 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0021-9517; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 6.844 | Times cited | 52 | Open Access | |
Notes | Approved | Most recent IF: 6.844; 2008 IF: 5.167 | |||
Call Number | UA @ lucian @ c:irua:103092 | Serial | 3409 | ||
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Author | Ovsyannikov, S.V.; Bykov, M.; Bykova, E.; Kozlenko, D.P.; Tsirlin, A.A.; Karkin, A.E.; Shchennikov, V.V.; Kichanov, S.E.; Gou, H.; Abakumov, A.M.; Egoavil, R.; Verbeeck, J.; McCammon, C.; Dyadkin, V.; Chernyshov, D.; van Smaalen, S.; Dubrovinsky, L.S. | ||||
Title | Charge-ordering transition in iron oxide Fe4O5 involving competing dimer and trimer formation | Type | A1 Journal article | ||
Year | 2016 | Publication | Nature chemistry | Abbreviated Journal | Nat Chem |
Volume | 8 | Issue | 8 | Pages | 501-508 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Phase transitions that occur in materials, driven, for instance, by changes in temperature or pressure, can dramatically change the materials' properties. Discovering new types of transitions and understanding their mechanisms is important not only from a fundamental perspective, but also for practical applications. Here we investigate a recently discovered Fe4O5 that adopts an orthorhombic CaFe3O5-type crystal structure that features linear chains of Fe ions. On cooling below approximately 150 K, Fe4O5 undergoes an unusual charge-ordering transition that involves competing dimeric and trimeric ordering within the chains of Fe ions. This transition is concurrent with a significant increase in electrical resistivity. Magnetic-susceptibility measurements and neutron diffraction establish the formation of a collinear antiferromagnetic order above room temperature and a spin canting at 85 K that gives rise to spontaneous magnetization. We discuss possible mechanisms of this transition and compare it with the trimeronic charge ordering observed in magnetite below the Verwey transition temperature. | ||||
Address | Bayerisches Geoinstitut, Universitat Bayreuth, Universitatsstrasse 30, D-95447, Bayreuth, Germany | ||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | English | Wos | 000374534100019 | Publication Date | 2016-04-04 |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1755-4330 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 25.87 | Times cited | 51 | Open Access | |
Notes | S.V.O. acknowledges the financial support of the Deutsche Forschungsgemeinschaft (DFG) under project OV-110/1-3. A.E.K. and V.V.S. acknowledge the support of the Russian Foundation for Basic Research (Project 14–02–00622a). H.G. acknowledges the support from the Alexander von Humboldt (AvH) Foundation and the National Natural Science Foundation of China (No. 51201148). A.M.A., R.E. and J.V. acknowledge financial support from the European Commission (EC) under the Seventh Framework Programme (FP7) under a contract for an Integrated Infrastructure Initiative, Reference No. 312483- ESTEEM2. R.E. acknowledges support from the EC under FP7 Grant No. 246102 IFOX. A.M.A. acknowledges funding from the Russian Science Foundation (Grant No. 14-13- 00680). A.A.T. acknowledges funding and from the Federal Ministry for Education and Research through the Sofja Kovalevkaya Award of the AvH Foundation. Funding from the Fund for Scientific Research Flanders under FWO Project G.0044.13N is acknowledged. M.B. and S.v.S. acknowledge support from the DFG under Project Sm55/15-2. We acknowledge the European Synchrotron Radiation Facility for the provision of synchrotron radiation facilities.; esteem2jra2; esteem2jra3 | Approved | Most recent IF: 25.87 | ||
Call Number | c:irua:133593 c:irua:133593UA @ admin @ c:irua:133593 | Serial | 4068 | ||
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Author | Park, D.-s.; Hadad, M.; Riemer, L.M.; Ignatans, R.; Spirito, D.; Esposito, V.; Tileli, V.; Gauquelin, N.; Chezganov, D.; Jannis, D.; Verbeeck, J.; Gorfman, S.; Pryds, N.; Muralt, P.; Damjanovic, D. | ||||
Title | Induced giant piezoelectricity in centrosymmetric oxides | Type | A1 Journal article | ||
Year | 2022 | Publication | Science | Abbreviated Journal | Science |
Volume | 375 | Issue | 6581 | Pages | 653-657 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Giant piezoelectricity can be induced in centrosymmetric oxides by controlling the long-range motion of oxygen vacancies. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000753975300036 | Publication Date | 2022-02-11 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0036-8075 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 56.9 | Times cited | 51 | Open Access | OpenAccess |
Notes | D.-S.P., V.E., N.P., P.M., and D.D. acknowledge the European Commission for project Biowings H2020 Fetopen 2018-2022 (grant no. 80127). N.P. acknowledges funding from the Villum Fonden for the NEED project (grant no. 00027993) and the Danish Council for Independent Research Technology and Production Sciences for the DFF-Research Project 3 (grant no. 00069B). S.G. acknowledges funding from the Israel Science Foundation (research grant 1561/18 and equipment grant 2247/18). This project has received funding from the European Union’s Horizon 2020 research and innovation program under grant no. 823717 – ESTEEM3. D.C. acknowledges TOP/BOF funding of the University of Antwerp. M.H. and P.M. acknowledge funding from the Swiss National Science Foundation (grant nos. 200020-162664/1 and 200021-143424/1); esteem3reported; esteem3TA | Approved | Most recent IF: 56.9 | ||
Call Number | EMAT @ emat @c:irua:185876 | Serial | 6909 | ||
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Author | Cooper, D.; Denneulin, T.; Bernier, N.; Béché, A.; Rouvière, J.-L. | ||||
Title | Strain mapping of semiconductor specimens with nm-scale resolution in a transmission electron microscope | Type | A1 Journal article | ||
Year | 2016 | Publication | Micron | Abbreviated Journal | Micron |
Volume | 80 | Issue | 80 | Pages | 145-165 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | The last few years have seen a great deal of progress in the development of transmission electron microscopy based techniques for strain mapping. New techniques have appeared such as dark field electron holography and nanobeam diffraction and better known ones such as geometrical phase analysis have been improved by using aberration corrected ultra-stable modern electron microscopes. In this paper we apply dark field electron holography, the geometrical phase analysis of high angle annular dark field scanning transmission electron microscopy images, nanobeam diffraction and precession diffraction, all performed at the state-of-the-art to five different types of semiconductor samples. These include a simple calibration structure comprising 10-nm-thick SiGe layers to benchmark the techniques. A SiGe recessed source and drain device has been examined in order to test their capabilities on 2D structures. Devices that have been strained using a nitride stressor have been examined to test the sensitivity of the different techniques when applied to systems containing low values of deformation. To test the techniques on modern semiconductors, an electrically tested device grown on a SOI wafer has been examined. Finally a GaN/AlN superlattice was tested in order to assess the different methods of measuring deformation on specimens that do not have a perfect crystalline structure. The different deformation mapping techniques have been compared to one another and the strengths and weaknesses of each are discussed. | ||||
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Publisher | Place of Publication | Oxford | Editor | ||
Language | Wos | 000366770100018 | Publication Date | 2015-09-15 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0968-4328 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 1.98 | Times cited | 50 | Open Access | |
Notes | Approved | Most recent IF: 1.98 | |||
Call Number | UA @ lucian @ c:irua:136446 | Serial | 4401 | ||
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Author | Liao, Z.; Gauquelin, N.; Green, R.J.; Müller-Caspary, K.; Lobato, I.; Li, L.; Van Aert, S.; Verbeeck, J.; Huijben, M.; Grisolia, M.N.; Rouco, V.; El Hage, R.; Villegas, J.E.; Mercy, A.; Bibes, M.; Ghosez, P.; Sawatzky, G.A.; Rijnders, G.; Koster, G. | ||||
Title | Metal–insulator-transition engineering by modulation tilt-control in perovskite nickelates for room temperature optical switching | Type | A1 Journal article | ||
Year | 2018 | Publication | America | Abbreviated Journal | P Natl Acad Sci Usa |
Volume | 115 | Issue | 38 | Pages | 9515-9520 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | In transition metal perovskites ABO3 the physical properties are largely driven by the rotations of the BO6 octahedra, which can be tuned in thin films through strain and dimensionality control. However, both approaches have fundamental and practical limitations due to discrete and indirect variations in bond angles, bond lengths and film symmetry by using commercially available substrates. Here, we introduce modulation tilt control as a new approach to tune the ground state of perovskite oxide thin films by acting explicitly on the oxygen octahedra rotation modes, i.e. directly on the bond angles. By intercalating the prototype SmNiO3 target material with a tilt-control layer, we cause the system to change the natural amplitude of a given rotation mode without affecting the interactions. In contrast to strain and dimensionality engineering, our method enables a continuous fine-tuning of the materials properties. This is achieved through two independent adjustable parameters: the nature of the tilt-control material (through its symmetry, elastic constants and oxygen rotation angles) and the relative thicknesses of the target and tilt-control materials. As a result, a magnetic and electronic phase diagram can be obtained, normally only accessible by A-site element substitution, within the single SmNiO3 compound. With this unique approach, we successfully adjusted the metal-insulator transition (MIT) to room temperature to fulfill the desired conditions for optical switching applications. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000447224900057 | Publication Date | 2018-09-05 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0027-8424 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 9.661 | Times cited | 50 | Open Access | OpenAccess |
Notes | We would like to acknowledge Prof. Z. Zhong for stimulated discussion. M.H., G.K. and G.R. acknowledge funding from DESCO program of the Dutch Foundation for Fundamental Research on Matter (FOM) with financial support from the Netherlands Organization for Scientific Research (NWO). This work was funded by the European Union Council under the 7th Framework Program (FP7) grant nr NMP3-LA-2010-246102 IFOX. J.V., S.V.A, N.G. and K.M.C. acknowledge funding from FWO projects G.0044.13N, G.0374.13N, G. 0368.15N, and G.0369.15N. The Qu-Ant-EM microscope was partly funded by the Hercules fund from the Flemish Government. N.G. acknowledges funding from the European Research Council under the 7th Framework Program (FP7), ERC Starting Grant 278510 VORTEX. N.G. and J.V. acknowledge financial support from the European Union under the Seventh Framework Program under a contract for an Integrated Infrastructure Initiative (Reference No. 312483- ESTEEM2). The Canadian work was supported by NSERC and the Max Planck-UBC Centre for Quantum Materials. Some experiments for this work were performed at the Canadian Light Source, which is funded by the Canada Foundation for Innovation, NSERC, the National Research Council of Canada, the Canadian Institutes of Health Research, the Government of Saskatchewan, Western Economic Diversification Canada, and the University of Saskatchewan. MB acknowledges funding from the European Research Council under the 7th Framework Program (FP7), ERC CoG grant MINT #615759. A.M. and Ph.G. were supported by the ARC project AIMED and F.R.S-FNRS PDR project HiT4FiT and acknowledge access to Céci computing facilities funded by F.R.S-FNRS (Grant No 2.5020.1), Tier-1 supercomputer of the Fédération Wallonie-Bruxelles funded by the Walloon Region (Grant No 1117545) and HPC resources from the PRACE project Megapasta. | Approved | Most recent IF: 9.661 | ||
Call Number | EMAT @ emat @c:irua:154784UA @ admin @ c:irua:154784 | Serial | 5059 | ||
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Author | Abakumov, A.M.; Morozov, V.A.; Tsirlin, A.A.; Verbeeck, J.; Hadermann, J. | ||||
Title | Cation ordering and flexibility of the BO42- tetrahedra in incommensurately modulated CaEu2(BO4)4 (B = Mo, W) scheelites | Type | A1 Journal article | ||
Year | 2014 | Publication | Inorganic chemistry | Abbreviated Journal | Inorg Chem |
Volume | 53 | Issue | 17 | Pages | 9407-9415 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | The factors mediating cation ordering in the scheelite-based molybdates and tungstates are discussed on the basis of the incommensurately modulated crystal structures of the CaEu2(BO4)(4) (B = Mo, W) red phosphors solved from high-resolution synchrotron powder X-ray diffraction data. Monoclinic CaEu2(WO4)(4) adopts a (3 + 1)-dimensionally modulated structure [superspace group I2/b(alpha beta 0)00, a = 5.238 73(1)A, b = 5.266 35(1) A, c = 11.463 19(9) A, gamma = 91.1511(2)degrees, q = 0.56153(6)a* + 0.7708(9)b*, R-F = 0.050, R-p = 0.069], whereas tetragonal CaEu2(MoO4)(4) is (3 + 2)-dimensionally modulated [superspace group I4(1)/ a(alpha beta 0)00(-beta alpha 0)00, a = 5.238 672(7) A, c = 11.548 43(2) A, q(1) = 035331(8)a* + 0.82068(9)b*, q(2) = -0.82068(9)a* + 0.55331(8)b*, R-F = 0.061, R-p = 0.082]. In both cases the modulation arises from the ordering of the Ca/Eu cations and the cation vacancies at the A-sublattice of the parent scheelite ABO(4) structure. The cation ordering is incomplete and better described with harmonic rather than with steplike occupational modulation functions. The structures respond to the variation of the effective charge and cation size at the A-position through the flexible geometry of the MoO42- and WO42- tetrahedra demonstrating an alternation of stretching the B-O bond lengths and bending the O-B-O bond angles. The tendency towards A-site cation ordering in scheelites is rationalized using the difference in ionic radii and concentration of the A-site vacancies as parameters and presented in the form of a structure map. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Easton, Pa | Editor | ||
Language | Wos | 000341229600068 | Publication Date | 2014-08-21 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0020-1669;1520-510X; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.857 | Times cited | 48 | Open Access | |
Notes | Fwo G039211n | Approved | Most recent IF: 4.857; 2014 IF: 4.762 | ||
Call Number | UA @ lucian @ c:irua:119292UA @ admin @ c:irua:119292 | Serial | 297 | ||
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Author | Tsirlin, A.A.; Nath, R.; Abakumov, A.M.; Furukawa, Y.; Johnston, D.C.; Hemmida, M.; Krug von Nidda, H.-A.; Loidl, A.; Geibel, C.; Rosner, H. | ||||
Title | Phase separation and frustrated square lattice magnetism of Na1.5VOPO4F0.5 | Type | A1 Journal article | ||
Year | 2011 | Publication | Physical review : B : condensed matter and materials physics | Abbreviated Journal | Phys Rev B |
Volume | 84 | Issue | 1 | Pages | 014429-014429,16 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Crystal structure, electronic structure, and magnetic behavior of the spin-1/2 quantum magnet Na1.5VOPO4F0.5 are reported. The disorder of Na atoms leads to a sequence of structural phase transitions revealed by synchrotron x-ray powder diffraction and electron diffraction. The high-temperature second-order α↔β transition at 500 K is of the order-disorder type, whereas the low-temperature β↔γ+γ′ transition around 250 K is of the first order and leads to a phase separation toward the polymorphs with long-range (γ) and short-range (γ′) order of Na. Despite the complex structural changes, the magnetic behavior of Na1.5VOPO4F0.5 probed by magnetic susceptibility, heat capacity, and electron spin resonance measurements is well described by the regular frustrated square lattice model of the high-temperature α-polymorph. The averaged nearest-neighbor and next-nearest-neighbor couplings are J̅ 1≃−3.7 K and J̅ 2≃6.6 K, respectively. Nuclear magnetic resonance further reveals the long-range ordering at TN=2.6 K in low magnetic fields. Although the experimental data are consistent with the simplified square-lattice description, band structure calculations suggest that the ordering of Na atoms introduces a large number of inequivalent exchange couplings that split the square lattice into plaquettes. Additionally, the direct connection between the vanadium polyhedra induces an unusually strong interlayer coupling having effect on the transition entropy and the transition anomaly in the specific heat. Peculiar features of the low-temperature crystal structure and the relation to isostructural materials suggest Na1.5VOPO4F0.5 as a parent compound for the experimental study of tetramerized square lattices as well as frustrated square lattices with different values of spin. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000293247400008 | Publication Date | 2011-07-28 | |
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 | 47 | Open Access | |
Notes | Approved | Most recent IF: 3.836; 2011 IF: 3.691 | |||
Call Number | UA @ lucian @ c:irua:91770 | Serial | 2588 | ||
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Author | Morozov, V.A.; Arakcheeva, A.V.; Chapuis, G.; Guiblin, N.; Rossell, M.D.; Van Tendeloo, G. | ||||
Title | KNd(MoO4)2: a new incommensurate modulated structure in the scheelite family | Type | A1 Journal article | ||
Year | 2006 | Publication | Chemistry of materials | Abbreviated Journal | Chem Mater |
Volume | 18 | Issue | 17 | Pages | 4075-4082 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | |||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Washington, D.C. | Editor | ||
Language | Wos | 000239758300022 | Publication Date | 2006-07-28 | |
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 | 46 | Open Access | |
Notes | Iap V-1 | Approved | Most recent IF: 9.466; 2006 IF: 5.104 | ||
Call Number | UA @ lucian @ c:irua:60688 | Serial | 3538 | ||
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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 | 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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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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