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Author Batuk, D.; Batuk, M.; Tsirlin, A.A.; Hadermann, J.; Abakumov, A.M. pdf  url
doi  openurl
  Title Trapping of Oxygen Vacancies at Crystallographic Shear Planes in Acceptor-Doped Pb-Based Ferroelectrics Type A1 Journal article
  Year 2015 Publication Angewandte Chemie: international edition in English Abbreviated Journal Angew Chem Int Edit  
  Volume 54 Issue 54 Pages 14787-14790  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract The defect chemistry of the ferroelectric material PbTiO3 after doping with Fe(III) acceptor ions is reported. Using advanced transmission electron microscopy and powder X-ray and neutron diffraction, we demonstrate that even at concentrations as low as circa 1.7% (material composition approximately ABO2.95), the oxygen vacancies are trapped into extended planar defects, specifically crystallographic shear planes. We investigate the evolution of these defects upon doping and unravel their detailed atomic structure using the formalism of superspace crystallography, thus unveiling their role in nonstoichiometry in the Pb-based perovskites.  
  Address Chemistry Department, Moscow State University, 119991, Moscow (Russia). artem.abakumov@uantwerpen.be  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Wos 000367723400031 Publication Date 2015-10-21  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 1433-7851 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 11.994 Times cited 3 Open Access  
  Notes A.M.A. is grateful to the Russian Science Foundation (grant 14-13-00680). AT was funded by the Mobilitas grant MTT77 of the ESF and by the Federal Ministry for Education and Research through the Sofja Kovalevskaya Award of Alexander von Humboldt Foundation. Approved Most recent IF: 11.994; 2015 IF: 11.261  
  Call Number c:irua:131104 Serial 4080  
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Author Kirsanova, M.A.; Olenev, A.V.; Abakumov, A.M.; Bykov, M.A.; Shevelkov, A.V. doi  openurl
  Title Extension of the clathrate family : the type X clathrate Ge79P29S18Te6 Type A1 Journal article
  Year 2011 Publication Angewandte Chemie: international edition in English Abbreviated Journal Angew Chem Int Edit  
  Volume 50 Issue 10 Pages 2371-2374  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Now they are 10! The title compound displays a new type of crystal structure and is labeled clathrate X according to the general classification of clathrate structures. In contrast to typical clathrates, this compound has three-coordinate atoms within the framework and combines distorted 24-vertex polyhedra (see picture, green) centered around tellurium guest atoms with very irregular 10-vertex polyhedra around sulfur atoms (yellow).  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Weinheim Editor  
  Language Wos 000288036300033 Publication Date 2011-01-31  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 1433-7851; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 11.994 Times cited 23 Open Access  
  Notes Approved Most recent IF: 11.994; 2011 IF: 13.455  
  Call Number UA @ lucian @ c:irua:88793 Serial 1158  
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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. pdf  doi
openurl 
  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.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Weinheim Editor  
  Language Wos 000313913300027 Publication Date 2012-12-22  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 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 Abakumov, A.M.; Hadermann, J.; Bals, S.; Nikolaev, I.V.; Antipov, E.V.; Van Tendeloo, G. pdf  doi
openurl 
  Title Crystallographic shear structures as a route to anion-deficient perovskites Type A1 Journal article
  Year 2006 Publication Angewandte Chemie: international edition in English Abbreviated Journal Angew Chem Int Edit  
  Volume 45 Issue 40 Pages 6697-6700  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Weinheim Editor  
  Language Wos 000241474500022 Publication Date 2006-09-13  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 1433-7851;1521-3773; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 11.994 Times cited 62 Open Access  
  Notes Approved Most recent IF: 11.994; 2006 IF: 10.232  
  Call Number UA @ lucian @ c:irua:61689 Serial 589  
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Author Fedotov, S.S.; Aksyonov, D.A.; Samarin, A.S.; Karakulina, O.M.; Hadermann, J.; Stevenson, K.J.; Khasanova, N.R.; Abakumov, A.M.; Antipov, E., V pdf  url
doi  openurl
  Title Tuning the crystal structure of A2CoPO4F(A=Li,Na) fluoride-phosphates : a new layered polymorph of LiNaCoPO4F Type A1 Journal article
  Year 2019 Publication European journal of inorganic chemistry Abbreviated Journal Eur J Inorg Chem  
  Volume 2019 Issue 2019 Pages 4365-4372  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Co-containing fluoride-phosphates are of interest in sense of delivering high electrode potentials and attractive specific energy values as positive electrode materials for rechargeable batteries. In this paper we report on a new Co-based fluoride-phosphate, LiNaCoPO4F, with a layered structure (2D), which was Rietveld-refined based on X-ray powder diffraction data [P2(1)/c, a = 6.83881(4) angstrom, b = 11.23323(5) angstrom, c = 5.07654(2) angstrom, beta = 90.3517(5) degrees, V = 389.982(3) angstrom(3)] and validated by electron diffraction and high-resolution scanning transmission electron microscopy. The differential scanning calorimetry measurements revealed that 2D-LiNaCoPO4F forms in a narrow temperature range of 520-530 degrees C and irreversibly converts to the known 3D-LiNaCoPO4F modification (Pnma) above 530 degrees C. The non-carbon-coated 2D-LiNaCoPO4F shows reversible electrochemical activity in Li-ion cell in the potential range of 3.0-4.9 V vs. Li/Li+ with an average potential of approximate to 4.5 V and in Na-ion cell in the range of 3.0-4.5 V vs. Na/Na+ exhibiting a plateau profile centered around 4.2 V, in agreement with the calculated potentials by density functional theory. The energy barriers for both Li+ and Na+ migration in 2D-LiNaCoPO4F amount to 0.15 eV along the [001] direction rendering 2D-LiNaCoPO4F as a viable electrode material for high-power Li- and Na-ion rechargeable batteries. The discovery and stabilization of the 2D-LiNaCoPO4F polymorph indicates that temperature influence on the synthesis of A(2)MPO(4)F fluoride-phosphates needs more careful examination with perspective to unveil new structures.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000484135500001 Publication Date 2019-08-07  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 1434-1948 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.444 Times cited Open Access  
  Notes ; This work is supported by the Russian Science Foundation (grant 17-73-30006). The authors greatly thank Dr. D. Rupasov for TG-DSC experiments, B. D. Shmykov and A. I. Manoilov for assistance with sample preparation, the Skoltech Center for Energy Science and Technology and the Moscow State University Program of Development up to 2020. J. Hadermann and O. M. Karakulina acknowledge support from the FWO under grant G040116N. ; Approved Most recent IF: 2.444  
  Call Number UA @ admin @ c:irua:162857 Serial 5403  
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Author Isaeva, A.A.; Makarevich, O.N.; Kutznetsov, A.N.; Doert, T.; Abakumov, A.M.; Van Tendeloo, G. doi  openurl
  Title Mixed tellurides Ni3-xGaTe2 (0\leq x\leq0.65): crystal and electronic structures, properties, and nickel deficiency effects on vacancy ordering Type A1 Journal article
  Year 2010 Publication European journal of inorganic chemistry Abbreviated Journal Eur J Inorg Chem  
  Volume Issue 9 Pages 1395-1404  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract The Ni3-xGaTe2 series of compounds (0 x 0.65) was synthesized by a high-temperature ceramic technique at 750 °C. Crystal structures of three compounds in the series were determined by X-ray powder diffraction: Ni2.98(1)GaTe2 (RI = 0.042, Rp = 0.023, Rwp = 0.035), Ni2.79(1)GaTe2 (RI = 0.053, Rp = 0.028, Rwp = 0.039), Ni2.58(1)GaTe2 (RI = 0.081, Rp = 0.037, Rwp = 0.056); the structures were verified by electron diffraction and, for the former compound, high-resolution electron microscopy. The compounds crystallize in a hexagonal lattice with P63/mmc, and the structures can be regarded as a hexagonal close-packed array with a -Ga-Te-Te- stacking sequence. The octahedral and trigonal bipyramidal voids in the hcp structure are selectively filled with Ni atoms to form one entirely occupied and two partially occupied sites, thus allowing variations in the nickel content in the series of compounds Ni3-xGaTe2 (0 x 0.65). A superstructure with asup = 2asub (P63/mmc) has been identified for Ni3-xGaTe2 (0.5 x 0.65) by electron diffraction. Real-space, high-resolution images confirm an ordering of Ni atoms and vacancies inthe ab plane. Quantum-chemical calculations performed forNi3-xGaTe2 (x = 0, 0.25, 0.75, 1) suggest anisotropic metallic conductivity and Pauli paramagnetic behavior that are experimentally confirmed for Ni3GaTe2.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Weinheim Editor  
  Language Wos 000276370300009 Publication Date 2010-02-12  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 1434-1948;1099-0682; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.444 Times cited 8 Open Access  
  Notes Approved Most recent IF: 2.444; 2010 IF: 2.910  
  Call Number UA @ lucian @ c:irua:82266 Serial 2090  
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Author Mefford, J.T.; Kurilovich, A.A.; Saunders, J.; Hardin, W.G.; Abakumov, A.M.; Forslund, R.P.; Bonnefont, A.; Dai, S.; Johnston, K.P.; Stevenson, K.J. url  doi
openurl 
  Title Decoupling the roles of carbon and metal oxides on the electrocatalytic reduction of oxygen on La1-xSrxCoO3-\delta perovskite composite electrodes Type A1 Journal article
  Year 2019 Publication Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys  
  Volume 21 Issue 6 Pages 3327-3338  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Perovskite oxides are active room-temperature bifunctional oxygen electrocatalysts in alkaline media, capable of performing the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) with lower combined overpotentials relative to their precious metal counterparts. However, their semiconducting nature necessitates the use of activated carbons as conductive supports to generate applicably relevant current densities. In efforts to advance the performance and theory of oxide electrocatalysts, the chemical and physical properties of the oxide material often take precedence over contributions from the conductive additive. In this work, we find that carbon plays an important synergistic role in improving the performance of La1-xSrxCoO3- (0 x 1) electrocatalysts through the activation of O-2 and spillover of radical oxygen intermediates, HO2- and O-2(-), which is further reduced through chemical decomposition of HO2- on the perovskite surface. Through a combination of thin-film rotating disk electrochemical characterization of the hydrogen peroxide intermediate reactions (hydrogen peroxide reduction reaction (HPRR), hydrogen peroxide oxidation reaction (HPOR)) and oxygen reduction reaction (ORR), surface chemical analysis, HR-TEM, and microkinetic modeling on La1-xSrxCoO3- (0 x 1)/carbon (with nitrogen and non-nitrogen doped carbons) composite electrocatalysts, we deconvolute the mechanistic aspects and contributions to reactivity of the oxide and carbon support.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000459584900049 Publication Date 2019-01-18  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 1463-9076; 1463-9084 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.123 Times cited 5 Open Access OpenAccess  
  Notes ; Financial support for this work was provided by the R. A. Welch Foundation (grants F-1529 and F-1319). S. D. was supported as part of the Fluid Interface Reactions, Structures and Transport (FIRST) Center, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, and Office of Basic Energy Sciences. ; Approved Most recent IF: 4.123  
  Call Number UA @ admin @ c:irua:158625 Serial 5244  
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Author Hadermann, J.; Van Tendeloo, G.; Abakumov, A.M.; Pavlyuk, B.P.; Rozova, M.G.; Antipov, E.V. doi  openurl
  Title Structural transformation in fluorinated LaACuGaO5 (A=Ca, Sr) brownmillerites Type A1 Journal article
  Year 2000 Publication International journal of inorganic materials Abbreviated Journal Int J Inorg Mater  
  Volume 2 Issue 6 Pages 493-502  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Amsterdam Editor  
  Language Wos 000165985400005 Publication Date 2002-07-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 1466-6049; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited 13 Open Access  
  Notes Approved Most recent IF: NA  
  Call Number UA @ lucian @ c:irua:36043 Serial 3265  
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Author Pearce, P.E.; Perez, A.J.; Rousse, G.; Saubanère, M.; Batuk, D.; Foix, D.; McCalla, E.; Abakumov, A.M.; Van Tendeloo, G.; Doublet, M.-L.; Tarascon, J.-M. url  doi
openurl 
  Title Evidence for anionic redox activity in a tridimensional-ordered Li-rich positive electrode β-Li2IrO3 Type A1 Journal article
  Year 2017 Publication Nature materials Abbreviated Journal Nat Mater  
  Volume 16 Issue 5 Pages 580-586  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Lithium-ion battery cathode materials have relied on cationic redox reactions until the recent discovery of anionic redox activity in Li-rich layered compounds which enables capacities as high as 300 mAh g(-1). In the quest for new high-capacity electrodes with anionic redox, a still unanswered question was remaining regarding the importance of the structural dimensionality. The present manuscript provides an answer. We herein report on a beta-Li2IrO3 phase which, in spite of having the Ir arranged in a tridimensional (3D) framework instead of the typical two-dimensional (2D) layers seen in other Li-rich oxides, can reversibly exchange 2.5 e(-) per Ir, the highest value ever reported for any insertion reaction involving d-metals. We show that such a large activity results from joint reversible cationic (Mn+) and anionic (O-2)(n-) redox processes, the latter being visualized via complementary transmission electron microscopy and neutron diffraction experiments, and confirmed by density functional theory calculations. Moreover, beta-Li2IrO3 presents a good cycling behaviour while showing neither cationic migration nor shearing of atomic layers as seen in 2D-layered Li-rich materials. Remarkably, the anionic redox process occurs jointly with the oxidation of Ir4+ at potentials as low as 3.4 V versus Li+/Li-0, as equivalently observed in the layered alpha-Li2IrO3 polymorph. Theoretical calculations elucidate the electrochemical similarities and differences of the 3D versus 2D polymorphs in terms of structural, electronic and mechanical descriptors. Our findings free the structural dimensionality constraint and broaden the possibilities in designing high-energy-density electrodes for the next generation of Li-ion batteries.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000400004200018 Publication Date 2017-02-27  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 1476-1122 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 39.737 Times cited Open Access Not_Open_Access  
  Notes The authors thank Q. Jacquet for fruitful discussions and V. Pomjakushin for his valuable help in neutron diffraction experiments. This work is based on experiments performed at the Swiss Spallation Neutron Source SINQ, Paul Scherrer Institute, Villigen, Switzerland. Use of the 11-BM mail service of the APS at Argonne National Laboratory was supported by the US Department of Energy under contract No. DE-AC02-06CH11357 and is greatly acknowledged. J.-M.T. acknowledges funding from the European Research Council (ERC) (FP/2014)/ERC Grant-Project 670116-ARPEMA. E.M. acknowledges financial support from the Fonds de Recherche du Quebec-Nature et Technologies. Approved Most recent IF: 39.737  
  Call Number EMAT @ emat @c:irua:147502 Serial 4773  
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Author Erni, R.; Abakumov, A.M.; Rossell, M.D.; Batuk, D.; Tsirlin, A.A.; Nénert, G.; Van Tendeloo, G. pdf  doi
openurl 
  Title Nanoscale phase separation in perovskites revisited Type L1 Letter to the editor
  Year 2014 Publication Nature materials Abbreviated Journal Nat Mater  
  Volume 13 Issue 3 Pages 216-217  
  Keywords L1 Letter to the editor; Electron microscopy for materials research (EMAT)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos 000331945200002 Publication Date 2014-02-20  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 1476-1122;1476-4660; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 39.737 Times cited 5 Open Access  
  Notes Approved Most recent IF: 39.737; 2014 IF: 36.503  
  Call Number UA @ lucian @ c:irua:114579 Serial 2270  
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Author Sathiya, M.; Abakumov, A.M.; Foix, D.; Rousse, G.; Ramesha, K.; Saubanère, M.; Doublet, M. .; Vezin, H.; Laisa, C.P.; Prakash, A.S.; Gonbeau, D.; Van Tendeloo, G.; Tarascon, J.M. pdf  url
doi  openurl
  Title Origin of voltage decay in high-capacity layered oxide electrodes Type A1 Journal article
  Year 2015 Publication Nature materials Abbreviated Journal Nat Mater  
  Volume 14 Issue 14 Pages 230-238  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Although Li-rich layered oxides (Li1+xNiyCozMn1−x−y−zO2 > 250 mAh g−1) are attractive electrode materials providing energy densities more than 15% higher than todays commercial Li-ion cells, they suffer from voltage decay on cycling. To elucidate the origin of this phenomenon, we employ chemical substitution in structurally related Li2RuO3 compounds. Li-rich layered Li2Ru1−yTiyO3 phases with capacities of ~240 mAh g−1 exhibit the characteristic voltage decay on cycling. A combination of transmission electron microscopy and X-ray photoelectron spectroscopy studies reveals that the migration of cations between metal layers and Li layers is an intrinsic feature of the chargedischarge process that increases the trapping of metal ions in interstitial tetrahedral sites. A correlation between these trapped ions and the voltage decay is established by expanding the study to both Li2Ru1−ySnyO3 and Li2RuO3; the slowest decay occurs for the cations with the largest ionic radii. This effect is robust, and the finding provides insights into new chemistry to be explored for developing high-capacity layered electrodes that evade voltage decay.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos 000348600200024 Publication Date 2014-12-01  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 1476-1122;1476-4660; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 39.737 Times cited 395 Open Access  
  Notes 246791 Countatoms; 312483 Esteem2; esteem2_ta Approved Most recent IF: 39.737; 2015 IF: 36.503  
  Call Number c:irua:132555 c:irua:132555 Serial 2528  
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Author Paria Sena, R.; Babaryk, A.A.; Khainakov, S.; Garcia-Granda, S.; Slobodyanik, N.S.; Van Tendeloo, G.; Abakumov, A.M.; Hadermann, J. pdf  url
doi  openurl
  Title A pseudo-tetragonal tungsten bronze superstructure: a combined solution of the crystal structure of K6.4(Nb,Ta)36.3O94 with advanced transmission electron microscopy and neutron diffraction Type A1 Journal article
  Year 2016 Publication Journal of the Chemical Society : Dalton transactions Abbreviated Journal Dalton T  
  Volume 45 Issue 45 Pages 973-979  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract The crystal structure of the K6.4Nb28.2Ta8.1O94 pseudo-tetragonal tungsten bronze-type oxide was determined using a combination of X-ray powder diffraction, neutron diffraction and transmission electron microscopy techniques, including electron diffraction, high angle annular dark field scanning transmission electron microscopy (HAADF-STEM), annular bright field STEM (ABF-STEM) and energy-dispersive X-ray compositional mapping (STEM-EDX). The compound crystallizes in the space group Pbam with unit cell parameters a = 37.468(9) A, b = 12.493(3) A, c = 3.95333(15) A. The structure consists of corner sharing (Nb,Ta)O6 octahedra forming trigonal, tetragonal and pentagonal tunnels. All tetragonal tunnels are occupied by K(+) ions, while 1/3 of the pentagonal tunnels are preferentially occupied by Nb(5+)/Ta(5+) and 2/3 are occupied by K(+) in a regular pattern. A fractional substitution of K(+) in the pentagonal tunnels by Nb(5+)/Ta(5+) is suggested by the analysis of the HAADF-STEM images. In contrast to similar structures, such as K2Nb8O21, also parts of the trigonal tunnels are fractionally occupied by K(+) cations.  
  Address Electron Microscopy for Materials Research (EMAT), University of Antwerp, Groenenborgerlaan 171, B-2020, Antwerp, Belgium. joke.hadermann@uantwerpen.be babaryk@univ.kiev.ua  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Wos 000367614700018 Publication Date 2015-11-23  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 1477-9226 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.029 Times cited 6 Open Access  
  Notes We thank Dr E. Suard and Dr O. Fabello for assistance in collecting the neutron diffraction data. R.P.S. acknowledges funding from the European Research Council under the 7th Framework Program (FP7), ERC Grant No. 246791-COUNTATOMS. The titan microscope was partly funded by the Hercules fund from the Flemish Government. The authors acknowledge financial support from the European Union under the Seventh Framework Program under a contract for an Integrated Infrastructure Initiative. Reference No. 312483-ESTEEM2. AAB acknowledges the JSPDS ICDD Grant-in-Aid program (12-02).; esteem2jra1; esteem2jra2 Approved Most recent IF: 4.029  
  Call Number c:irua:130408 c:irua:130408 Serial 3998  
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Author Tyablikov, O.A.; Batuk, D.; Tsirlin, A.A.; Batuk, M.; Verchenko, V.Y.; Filimonov, D.S.; Pokholok, K.V.; Sheptyakov, D.V.; Rozova, M.G.; Hadermann, J.; Antipov, E.V.; Abakumov, A.M.; pdf  url
doi  openurl
  Title {110}-Layered B-cation ordering in the anion-deficient perovskite Pb2.4Ba2.6Fe2Sc2TiO13 with the crystallographic shear structure Type A1 Journal article
  Year 2015 Publication Journal of the Chemical Society : Dalton transactions Abbreviated Journal Dalton T  
  Volume 44 Issue 44 Pages 10753-10762  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract A novel anion-deficient perovskite-based compound, Pb2.4Ba2.6Fe2Sc2TiO13, was synthesized via the citrate-based route. This compound is an n = 5 member of the A(n)B(n)O(3n-2) homologous series with unit-cell parameters related to the perovskite subcell a(p) approximate to 4.0 angstrom as a(p)root 2 x a(p) x 5a(p)root 2. The crystal structure of Pb2.4Ba2.6Fe2Sc2TiO13 consists of quasi-2D perovskite blocks with a thickness of three octahedral layers separated by the 1/2[110]((1) over bar 01)(p) crystallographic shear (CS) planes, which are parallel to the {110} plane of the perovskite subcell. The CS planes transform the corner-sharing octahedra into chains of edge-sharing distorted tetragonal pyramids. Using a combination of neutron powder diffraction, Fe-57 Mossbauer spectroscopy and atomic resolution electron energy-loss spectroscopy we demonstrate that the B-cations in Pb2.4Ba2.6Fe2Sc2TiO13 are ordered along the {110} perovskite layers with Fe3+ in distorted tetragonal pyramids along the CS planes, Ti4+ preferentially in the central octahedra of the perovskite blocks and Sc3+ in the outer octahedra of the perovskite blocks. Magnetic susceptibility and Mossbauer spectroscopy indicate a broadened magnetic transition around T-N similar to 45 K and the onset of local magnetic fields at low temperatures. The magnetic order is probably reminiscent of that in other A(n)B(n)O(3n-2) homologues, where G-type AFM order within the perovskite blocks has been observed.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos 000355701000026 Publication Date 2015-01-26  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 1477-9226;1477-9234; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.029 Times cited 1 Open Access  
  Notes Approved Most recent IF: 4.029; 2015 IF: 4.197  
  Call Number c:irua:127001 Serial 22  
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Author Mikhailova, D.; Reichel, P.; Tsirlin, A.A.; Abakumov, A.M.; Senyshyn, A.; Mogare, K.M.; Schmidt, M.; Kuo, C.Y.; Pao, C.W.; Pi, T.W.; Lee, J.F.; Hu, Z.; Tjeng, L.H.; doi  openurl
  Title Oxygen-driven competition between low-dimensional structures of Sr3CoMO6 and Sr3CoMO7-\delta with M = Ru,Ir Type A1 Journal article
  Year 2014 Publication Journal of the Chemical Society : Dalton transactions Abbreviated Journal Dalton T  
  Volume 43 Issue 37 Pages 13883-13891  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract We have realized a reversible structure transformation of one-dimensional 1D K4CdCl6-type Sr3CoMO6 with the Co2+/M4+ cation ordering into the two-dimensional 2D double layered Ruddlesden-Popper structure Sr3CoMO7-delta with a random distribution of Co and M (with M = Ru, Ir) upon increasing the partial oxygen pressure. The combined soft and hard X-ray absorption spectroscopy studies show that under transformation, Co and M cations were oxidized to Co3+ and M5+. During oxidation, high-spin Co2+ in Sr3CoMO6 first transforms into high-spin Co3+ in oxygen-deficient Sr3CoMO7-delta, and then further transforms into low-spin Co3+ in fully oxidized Sr3CoMO7 upon further increasing the partial pressure of oxygen. The 1D Sr3CoMO6 compound is magnetically ordered at low temperatures with the magnetic moments lying along the c-axis. Their alignment is parallel for Sr3CoRuO6 and antiparallel for Sr3CoIrO6. The 2D compounds reveal a spin-glass-like behavior related to the random distribution of magnetic cations in the structure.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos 000342074100009 Publication Date 2014-07-28  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 1477-9226;1477-9234; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.029 Times cited 7 Open Access  
  Notes Approved Most recent IF: 4.029; 2014 IF: 4.197  
  Call Number UA @ lucian @ c:irua:119960 Serial 2545  
Permanent link to this record
 

 
Author Karakulina, O.M.; Demortière, A.; Dachraoui, W.; Abakumov, A.M.; Hadermann, J. url  doi
openurl 
  Title In Situ Electron Diffraction Tomography Using a Liquid-Electrochemical Transmission Electron Microscopy Cell for Crystal Structure Determination of Cathode Materials for Li-Ion batteries Type A1 Journal article
  Year 2018 Publication Nano letters Abbreviated Journal Nano Lett  
  Volume 18 Issue 10 Pages 6286-6291  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract We demonstrate that changes in the unit cell structure of lithium battery cathode materials during electrochemical cycling in liquid electrolyte can be determined for particles of just a few hundred nanometers in size using in situ transmission electron microscopy (TEM). The atomic coordinates, site occupancies (including lithium occupancy), and cell parameters of the materials can all be reliably quantified. This was achieved using electron diffraction tomography (EDT) in a sealed electrochemical cell with conventional liquid electrolyte (LP30) and LiFePO4 crystals, which have a well-documented charged structure to use as reference. In situ EDT in a liquid environment cell provides a viable alternative to in situ X-ray and neutron diffraction experiments due to the more local character of TEM, allowing for single crystal diffraction data to be obtained from multiphased powder samples and from submicrometer- to nanometer-sized particles. EDT is the first in situ TEM technique to provide information at the unit cell level in the liquid environment of a commercial TEM electrochemical cell. Its application to a wide range of electrochemical experiments in liquid environment cells and diverse types of crystalline materials can be envisaged.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000447355400024 Publication Date 2018-10-10  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 1530-6984 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 12.712 Times cited 12 Open Access Not_Open_Access: Available from 08.09.2019  
  Notes O.M. Karakulina, A.M. Abakumov and J. Hadermann acknowledge support from FWO under grant G040116N. A. Demortière wants to thank the French network on the electrochemical energy storage (RS2E), the Store-Ex Labex, for the financial support. Finally, the Fonds Européen de Développement Régional (FEDER), CNRS, Région Hauts-de-France, and Ministère de l’Education Nationale de l’Enseignement Supérieur et de la Recherche are acknowledged for funding. Approved Most recent IF: 12.712  
  Call Number EMAT @ emat @c:irua:154750 Serial 5063  
Permanent link to this record
 

 
Author Vishwakarma, M.; Karakulina, O.M.; Abakumov, A.M.; Hadermann, J.; Mehta, B.R. pdf  url
doi  openurl
  Title Nanoscale Characterization of Growth of Secondary Phases in Off-Stoichiometric CZTS Thin Films Type A1 Journal article
  Year 2018 Publication Journal of nanoscience and nanotechnology Abbreviated Journal J Nanosci Nanotechno  
  Volume 18 Issue 3 Pages 1688-1695  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract The presence of secondary phases is one of the main issues that hinder the growth of pure kesterite Cu2ZnSnS4 (CZTS) based thin films with suitable electronic and junction properties for efficient solar cell devices. In this work, CZTS thin films with varied Zn and Sn content have been prepared by RF-power controlled co-sputtering deposition using Cu, ZnS and SnS targets and a subsequent sulphurization step. Detailed TEM investigations show that the film shows a layered structure with the majority of the top layer being the kesterite phase. Depending on the initial thin film composition, either about ~1 μm Cu-rich and Zn-poor kesterite or stoichiometric CZTS is formed as top layer. X-ray diffraction, Raman spectroscopy and transmission electron microscopy reveal the presence of Cu2−x S, ZnS and SnO2 minor secondary phases in the form of nanoinclusions or nanoparticles or intermediate layers.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000426033400022 Publication Date 2018-03-01  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 1533-4880 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.483 Times cited Open Access Not_Open_Access  
  Notes Manoj Vishwakarma acknowl- edges IIT Delhi for MHRD fellowship. Professor B. R. Mehta acknowledges the support of the Schlumberger chair professorship. Manoj Vishwakarma, Joke Hadermann and Olesia M. karakulina acknowledge support provided by InsoL-DST. Manoj Vishwakarma acknowledges sup- port provided by CSIR funded projects and the support of DST-FIST Raman facility. References Approved Most recent IF: 1.483  
  Call Number EMAT @ emat @c:irua:147505 Serial 4775  
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Author Abakumov, M.A.; Nukolova, N.V.; Sokolsky-Papkov, M.; Shein, S.A.; Sandalova, T.O.; Vishwasrao, H.M.; Grinenko, N.F.; Gubsky, I.L.; Abakumov, A.M.; Kabanov, A.V.; Chekhonin, V.P.; pdf  url
doi  openurl
  Title VEGF-targeted magnetic nanoparticles for MRI visualization of brain tumor Type A1 Journal article
  Year 2015 Publication Nanomedicine: nanotechnology, biology and medicine Abbreviated Journal Nanomed-Nanotechnol  
  Volume 11 Issue 11 Pages 825-833  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract This work is focused on synthesis and characterization of targeted magnetic nanoparticles as magnetic resonance imaging (MRI) agents for in vivo visualization of gliomas. Ferric oxide (Fe3O4) cores were synthesized by thermal decomposition and coated with bovine serum albumin (BSA) to form nanoparticles with D-eff of 53 +/- 9 nm. The BSA was further cross-linked to improve colloidal stability. Monoclonal antibodies against vascular endothelial growth factor (mAbVEGF) were covalently conjugated to BSA through a polyethyleneglycol linker. Here we demonstrate that 1) BSA coated nanoparticles are stable and non-toxic to different cells at concentration up to 2.5 mg/mL; 2) conjugation of monoclonal antibodies to nanoparticles promotes their binding to VEGF-positive glioma C6 cells in vitro; 3) targeted nanoparticles are effective in MRI visualization of the intracranial glioma. Thus, mAbVEGF-targeted BSA-coated magnetic nanoparticles are promising MRI contrast agents for glioma visualization. (C) 2015 Elsevier Inc. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication S.l. Editor  
  Language Wos 000354559600004 Publication Date 2015-01-31  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 1549-9634; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 5.72 Times cited 62 Open Access  
  Notes Approved Most recent IF: 5.72; 2015 IF: 6.155  
  Call Number c:irua:126351 Serial 3838  
Permanent link to this record
 

 
Author Gonnissen, J.; Batuk, D.; Nataf, G.F.; Jones, L.; Abakumov, A.M.; Van Aert, S.; Schryvers, D.; Salje, E.K.H. pdf  doi
openurl 
  Title Direct Observation of Ferroelectric Domain Walls in LiNbO3: Wall-Meanders, Kinks, and Local Electric Charges Type A1 Journal article
  Year 2016 Publication Advanced functional materials Abbreviated Journal Adv Funct Mater  
  Volume 26 Issue 26 Pages 7599-7604  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract Direct observations of the ferroelectric domain boundaries in LiNbO3 are performed using high-resolution high-angle annular dark field scanning transmission electron microscopy imaging, revealing a very narrow width of the domain wall between the 180° domains. The domain walls demonstrate local side-way meandering, which results in inclinations even when the overall wall orientation follows the ferroelectric polarization. These local meanders contain kinks with “head-to-head” and “tail-to-tail” dipolar configurations and are therefore locally charged. The charged meanders are confined to a few cation layers along the polarization direction and are separated by longer stretches of straight domain walls.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000388166700006 Publication Date 2016-09-16  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 1616-301X ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 12.124 Times cited 23 Open Access  
  Notes J.G. acknowledges the support from the Research Foundation Flanders (FWO, Belgium) through various project fundings (G.0368.15N, G.0369.15N, and G.0374.13N), as well as the financial support from the European Union Seventh Framework Program (FP7/2007–2013) under Grant agreement no. 312483 (ESTEEM2). The authors thank J. Hadermann for useful suggestions on the interpretation of the HAADFSTEM images. E.K.H.S. thanks the EPSRC (EP/K009702/1) and the Leverhulme Trust (EM-2016-004) for support. G.F.N. thanks the National Research Fund, Luxembourg (FNR/P12/4853155/Kreisel) for support.; esteem2_jra2 Approved Most recent IF: 12.124  
  Call Number c:irua:135336 c:irua:135336 Serial 4129  
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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. pdf  url
doi  openurl
  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 (up) 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 O'Sullivan, M.; Hadermann, J.; Dyer, M.S.; Turner, S.; Alaria, J.; Manning, T.D.; Abakumov, A.M.; Claridge, J.B.; Rosseinsky, M.J. pdf  doi
openurl 
  Title Interface control by chemical and dimensional matching in an oxide heterostructure Type A1 Journal article
  Year 2016 Publication Nature chemistry Abbreviated Journal Nat Chem  
  Volume 8 Issue 8 Pages 347-353  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Interfaces between different materials underpin both new scientific phenomena, such as the emergent behaviour at oxide interfaces, and key technologies, such as that of the transistor. Control of the interfaces between materials with the same crystal structures but different chemical compositions is possible in many materials classes, but less progress has been made for oxide materials with different crystal structures. We show that dynamical self-organization during growth can create a coherent interface between the perovskite and fluorite oxide structures, which are based on different structural motifs, if an appropriate choice of cations is made to enable this restructuring. The integration of calculation with experimental observation reveals that the interface differs from both the bulk components and identifies the chemical bonding requirements to connect distinct oxide structures.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000372505500013 Publication Date 2016-02-01  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 1755-4330; 1755-4349 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 25.87 Times cited 28 Open Access  
  Notes Approved Most recent IF: 25.87  
  Call Number UA @ lucian @ c:irua:133189 Serial 4199  
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Author Voorhaar, L.; Diaz, M.M.; Leroux, F.; Rogers, S.; Abakumov, A.M.; Van Tendeloo, G.; Van Assche, G.; Van Mele, B.; Hoogenboom, R. url  doi
openurl 
  Title Supramolecular thermoplastics and thermoplastic elastomer materials with self-healing ability based on oligomeric charged triblock copolymers Type A1 Journal article
  Year 2017 Publication NPG Asia materials Abbreviated Journal Npg Asia Mater  
  Volume 9 Issue Pages e385  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Supramolecular polymeric materials constitute a unique class of materials held together by non-covalent interactions. These dynamic supramolecular interactions can provide unique properties such as a strong decrease in viscosity upon relatively mild heating, as well as self-healing ability. In this study we demonstrate the unique mechanical properties of phase-separated electrostatic supramolecular materials based on mixing of low molar mass, oligomeric, ABA-triblock copolyacrylates with oppositely charged outer blocks. In case of well-chosen mixtures and block lengths, the charged blocks are phase separated from the uncharged matrix in a hexagonally packed nanomorphology as observed by transmission electron microscopy. Thermal and mechanical analysis of the material shows that the charged sections have a T-g closely beyond room temperature, whereas the material shows an elastic response at temperatures far above this T-g ascribed to the electrostatic supramolecular interactions. A broad set of materials having systematic variations in triblock copolymer structures was used to provide insights in the mechanical properties and and self-healing ability in correlation with the nanomorphology of the materials.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000402065300005 Publication Date 2017-05-26  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 1884-4049; 1884-4057 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 9.157 Times cited 8 Open Access OpenAccess  
  Notes ; This research was conducted in the framework of the SIM-SHE/NAPROM project and SIM is gratefully acknowledged for the financial support. ; Approved Most recent IF: 9.157  
  Call Number UA @ lucian @ c:irua:144263 Serial 4691  
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Author Marikutsa, A.V.; Rumyantseva, M.N.; Frolov, D.D.; Morozov, I.V.; Boltalin, A.I.; Fedorova, A.A.; Petukhov, I.A.; Yashina, L.V.; Konstantinova, E.A.; Sadovskaya, E.M.; Abakumov, A.M.; Zubavichus, Y.V.; Gaskov, A.M.; doi  openurl
  Title Role of PdOx and RuOy clusters in oxygen exchange between nanocrystalline tin dioxide and the gas phase Type A1 Journal article
  Year 2013 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C  
  Volume 117 Issue 45 Pages 23858-23867  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract The effect of palladium- and ruthenium-based clusters on nanocrystalline tin dioxide interaction with oxygen was studied by temperature-programmed oxygen isotopic exchange with mass-spectrometry detection. The modification of aqueous sol-gel prepared SnO2 by palladium and, to a larger extent, by ruthenium, increases surface oxygen concentration on the materials. The revealed effects on oxygen exchange-lowering the threshold temperature, separation of surface oxygen contribution to the process, increase of heteroexchange rate and oxygen diffusion coefficient, decrease of activation energies of exchange and diffusion-were more intensive for Ru-modified SnO2 than in the case of SnO2/Pd. The superior promoting activity of ruthenium on tin dioxide interaction with oxygen was interpreted by favoring the dissociative O-2 adsorption and increasing the oxygen mobility, taking into account the structure and chemical composition of the modifier clusters.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Washington, D.C. Editor  
  Language Wos 000327110500046 Publication Date 2013-10-04  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 1932-7447;1932-7455; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.536 Times cited 20 Open Access  
  Notes Approved Most recent IF: 4.536; 2013 IF: 4.835  
  Call Number UA @ lucian @ c:irua:112706 Serial 2924  
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Author Altantzis, T.; Coutino-Gonzalez, E.; Baekelant, W.; Martinez, G.T.; Abakumov, A.M.; Van Tendeloo, G.; Roeffaers, M.B.J.; Bals, S.; Hofkens, J. pdf  url
doi  openurl
  Title Direct Observation of Luminescent Silver Clusters Confined in Faujasite Zeolites Type A1 Journal article
  Year 2016 Publication ACS nano Abbreviated Journal Acs Nano  
  Volume 10 Issue 10 Pages 7604-7611  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract One of the ultimate goals in the study of metal clusters is the correlation between the atomic-scale organization and their physicochemical properties. However, direct observation of the atomic organization of such minuscule metal clusters is heavily hindered by radiation damage imposed by the different characterization techniques. We present direct evidence of the structural arrangement, at an atomic level, of luminescent silver species stabilized in faujasite (FAU) zeolites using aberration-corrected scanning transmission electron microscopy. Two different silver clusters were identified in Ag-FAU zeolites, a trinuclear silver species associated with green emission and a tetranuclear silver species related to yellow emission. By combining direct imaging with complementary information obtained from X-ray powder diffraction and Rietveld analysis, we were able to elucidate the main differences at an atomic scale between luminescent (heat-treated) and nonluminescent (cation-exchanged) Ag-FAU zeolites. It is expected that such insights will trigger the directed synthesis of functional metal nanocluster-zeolite composites with tailored luminescent properties.  
  Address RIES, Hokkaido University , N20W10, Kita-Ward Sapporo 001-0020, Japan  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Wos 000381959100043 Publication Date 2016-07-08  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 1936-0851 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 13.942 Times cited 57 Open Access OpenAccess  
  Notes The authors gratefully acknowledge financial support from the Belgian Federal government (Belspo through the IAP-VI/27 and IAP-VII/05 programs), the European Union’s Seventh Framework Programme (FP7/2007-2013 under grant agreement no. 310651 SACS and no. 312483-ESTEEM2), the Flemish government in the form of long-term structural funding “Methusalem” grant METH/15/04 CASAS2, the Hercules foundation (HER/11/14), the “Strategisch Initiatief Materialen” SoPPoM program, and the Fund for Scientific Research Flanders (FWO) grants G.0349.12 and G.0B39.15. S.B. acknowledges funding from ERC Starting Grant COLOURATOMS (335078). The authors thank Prof. S. Van Aert for helpful discussions, Dr. T. De Baerdemaeker for XRD measurements, Mr. B. Dieu for the preparation of graphical material, and UOP Antwerp for the kind donation of zeolite samples.; esteem2jra4; ECASSara; (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); Approved Most recent IF: 13.942  
  Call Number c:irua:134576 c:irua:134576 Serial 4102  
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Author Rossell, M.D.; Abakumov, A.M.; Ramasse, Q.M.; Erni, R. doi  openurl
  Title Direct evidence of stacking disorder in the mixed ionic-electronic conductor Sr4Fe6O12+\delta Type A1 Journal article
  Year 2013 Publication ACS nano Abbreviated Journal Acs Nano  
  Volume 7 Issue 4 Pages 3078-3085  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract Determining the structure-to-property relationship of materials becomes particularly challenging when the material under investigation is dominated by defects and structural disorder. Knowledge on the exact atomic arrangement at the defective structure is required to understand its influence on the functional properties. However, standard diffraction techniques deliver structural information that is averaged over many unit cells. In particular, information about defects and order-disorder phenomena is contained in the coherent diffuse scattering intensity which often is difficult to uniquely interpret. Thus, the examination of the local disorder in materials requires a direct method to study their structure on the atomic level with chemical sensitivity. Using aberration-corrected scanning transmission electron microscopy in combination with atomic-resolution electron energy-loss spectroscopy, we show that the controversial structural arrangement of the Fe2O2+delta layers in the mixed ionic-electronic conducting Sr4Fe6O12+delta perovskite can be unambiguously resolved. Our results provide direct experimental evidence for the presence of a nanomixture of “ordered” and “disordered” domains in an epitaxial Sr4Fe6O12+delta thin film. The most favorable arrangement is the disordered structure and is interpreted as a randomly occurring but well-defined local shift of the Fe-O chains in the Fe2O2+delta layers. By analyzing the electron energy-loss near-edge structure of the different building blocks in the Sr4Fe6O12+delta unit cell we find that the mobile holes in this mixed ionic-electronic conducting oxide are highly localized in the Fe2O2+delta layers, which are responsible for the oxide-ion conductivity. A possible link between disorder and oxygen-ion transport along the Fe2O2+delta layers is proposed by arguing that the disorder can effectively break the oxygen diffusion pathways.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000318143300021 Publication Date 2013-03-04  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 1936-0851;1936-086X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 13.942 Times cited 4 Open Access  
  Notes Approved Most recent IF: 13.942; 2013 IF: 12.033  
  Call Number UA @ lucian @ c:irua:108476 Serial 713  
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Author Zhang, B.; Dugas, R.; Rousse, G.; Rozier, P.; Abakumov, A.M.; Tarascon, J.-M. url  doi
openurl 
  Title Insertion compounds and composites made by ball milling for advanced sodium-ion batteries Type A1 Journal article
  Year 2016 Publication Nature communications Abbreviated Journal Nat Commun  
  Volume 7 Issue 7 Pages 10308  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract Sodium-ion batteries have been considered as potential candidates for stationary energy storage because of the low cost and wide availability of Na sources. However, their future commercialization depends critically on control over the solid electrolyte interface formation, as well as the degree of sodiation at the positive electrode. Here we report an easily scalable ball milling approach, which relies on the use of metallic sodium, to prepare a variety of sodium-based alloys, insertion layered oxides and polyanionic compounds having sodium in excess such as the Na4V2(PO4)(2)F-3 phase. The practical benefits of preparing sodium-enriched positive electrodes as reservoirs to compensate for sodium loss during solid electrolyte interphase formation are demonstrated by assembling full C/P'2-Na-1[Fe0.5Mn0.5]O-2 and C/'Na3+xV2(PO4)(2)F-3' sodium-ion cells that show substantial increases (>10%) in energy storage density. Our findings may offer electrode design principles for accelerating the development of the sodium-ion technology.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000369021400002 Publication Date 2016-01-18  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 2041-1723 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 12.124 Times cited 104 Open Access  
  Notes Approved Most recent IF: 12.124  
  Call Number UA @ lucian @ c:irua:131599 Serial 4197  
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Author Mefford, J.T.; Rong, X.; Abakumov, A.M.; Hardin, W.G.; Dai, S.; Kolpak, A.M.; Johnston, K.P.; Stevenson, K.J. url  doi
openurl 
  Title Water electrolysis on La1-xSrxCoO3-\delta perovskite electrocatalysts Type A1 Journal article
  Year 2016 Publication Nature communications Abbreviated Journal Nat Commun  
  Volume 7 Issue 7 Pages 11053  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract Perovskite oxides are attractive candidates as catalysts for the electrolysis of water in alkaline energy storage and conversion systems. However, the rational design of active catalysts has been hampered by the lack of understanding of the mechanism of water electrolysis on perovskite surfaces. Key parameters that have been overlooked include the role of oxygen vacancies, B-O bond covalency, and redox activity of lattice oxygen species. Here we present a series of cobaltite perovskites where the covalency of the Co-O bond and the concentration of oxygen vacancies are controlled through Sr2+ substitution into La1 – xSrxCoO3 – delta. We attempt to rationalize the high activities of La1 – xSrxCoO3 – delta through the electronic structure and participation of lattice oxygen in the mechanism of water electrolysis as revealed through ab initio modelling. Using this approach, we report a material, SrCoO2.7, with a high, room temperature-specific activity and mass activity towards alkaline water electrolysis.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000372721700001 Publication Date 2016-03-23  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 2041-1723 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 12.124 Times cited 278 Open Access  
  Notes Financial support for this work was provided by the R.A. Welch Foundation (grants F-1529 and F-1319). X.R. and A.M.K. acknowledge support from the Skoltech-MIT Center for Electrochemical Energy Storage. Computations were performed using computational resources from XSEDE and NERSC. S.D. was supported as part of the Fluid Interface Reactions, Structures and Transport (FIRST) Center, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, and Office of Basic Energy Sciences. We thank D.W. Redman for help with the RHE measurements. Approved Most recent IF: 12.124  
  Call Number UA @ lucian @ c:irua:133242 Serial 4276  
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Author Dubrovinsky, L.; Dubrovinskaia, N.; Prakapenka, V.B.; Abakumov, A.M. url  doi
openurl 
  Title Implementation of micro-ball nanodiamond anvils for high-pressure studies above 6 Mbar Type A1 Journal article
  Year 2012 Publication Nature communications Abbreviated Journal Nat Commun  
  Volume 3 Issue Pages 1163-1167  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract Since invention of the diamond anvil cell technique in the late 1950s for studying materials at extreme conditions, the maximum static pressure generated so far at room temperature was reported to be about 400 GPa. Here we show that use of micro-semi-balls made of nanodiamond as second-stage anvils in conventional diamond anvil cells drastically extends the achievable pressure range in static compression experiments to above 600 GPa. Micro-anvils (10-50 mu m in diameter) of superhard nano-diamond (with a grain size below similar to 50 nm) were synthesized in a large volume press using a newly developed technique. In our pilot experiments on rhenium and gold we have studied the equation of state of rhenium at pressures up to 640 GPa and demonstrated the feasibility and crucial necessity of the in situ ultra high-pressure measurements for accurate determination of material properties at extreme conditions.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000313514100073 Publication Date 2012-10-23  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 2041-1723; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 12.124 Times cited 150 Open Access  
  Notes Approved Most recent IF: 12.124; 2012 IF: 10.015  
  Call Number UA @ lucian @ c:irua:110134 Serial 1563  
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Author Lieberman, C.M.; Filatov, A.S.; Wei, Z.; Rogachev, A.Y.; Abakumov, A.M.; Dikarev, E.V. url  doi
openurl 
  Title Mixed-valent, heteroleptic homometallic diketonates as templates for the design of volatile heterometallic precursors Type A1 Journal article
  Year 2015 Publication Chemical science Abbreviated Journal Chem Sci  
  Volume 6 Issue 6 Pages 2835-2842  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract A novel series of mixed-valent, heteroleptic transition metal diketonates that can be utilized as prospective single-source precursors for the low-temperature preparation of oxide materials are reported. The first mixed-valent iron beta-diketonates with different Fe-III/Fe-II ratios have been synthesized by applying the mixed-ligand approach. Based on nearly quantitative reaction yields and analysis of iron-oxygen bonds, these compounds were formulated as [Fe-III(acac)(3)][Fe-II(hfac)(2)] (1) and [Fe-II(hfac)(2)][Fe-III(acac)(3)][Fe-II(hfac)(2)] (2). In the above heteroleptic complexes, the Lewis acidic, coordinatively unsaturated Fe-II centers chelated by two hfac (hexafluoroacetylacetonate) ligands with electron-withdrawing substituents maintain bridging interactions with oxygen atoms of electron-donating acac (acetylacetonate) groups that chelate the neighboring Fe-III atoms. Switching the ligands on Fe-III and Fe-II atoms in starting reagents resulted in the instant ligand exchange between iron centers and in yet another polynuclear homometallic diketonate [Fe-II(hfac)(2)][Fe-III(acac)(2)(hfac)][Fe-II(hfac)(2)] (3) that adheres to the same bonding pattern as in complexes 1 and 2. The proposed synthetic methodology has been extended to design heterometallic diketonates with different M : M' ratios. Homometallic parent molecules have been used as templates to obtain heterometallic mixed-valent [Fe-III(acac)(3)][Mn-II(hfac)(2)] (4) and [Ni-II(hfac)(2)] – [Fe-III(acac)(3)][Ni-II(hfac)(2)] (5) complexes. The combination of two different diketonate ligands with electron-donating and electron-withdrawing substituents was found to be crucial for maintaining the above mixed-valent heterometallic assemblies. Theoretical investigation of two possible “isomers”, [Fe-III(acac)(3)][Mn-II(hfac)(2)] (4) and [Mn-III(acac)(3)][Fe-II(hfac)(2)] (40) provided an additional support for the metal site assignment giving a preference of 9.78 kcal mol(-1) for the molecule 4. Heterometallic complexes obtained in the course of this study have been found to act as effective single-source precursors for the synthesis of mixed-transition metal oxide materials MxM2-xO3 and MxMi-xO. The title highly volatile precursors can be used for the low-temperature preparation of both amorphous and crystalline heterometallic oxides in the form of thin films or nanosized particles that are known to operate as efficient catalysts in oxygen evolution reaction.  
  Address  
  Corporate Author Thesis  
  Publisher Royal Society of Chemistry Place of Publication Cambridge Editor  
  Language Wos 000353223100021 Publication Date 2015-02-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 2041-6520;2041-6539; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 8.668 Times cited 13 Open Access  
  Notes Approved Most recent IF: 8.668; 2015 IF: 9.211  
  Call Number c:irua:126031 Serial 2092  
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Author Yang, T.; Abakumov, A.M.; Hadermann, J.; Van Tendeloo, G.; Nowik, I.; Stephens, P.W.; Hamberger, J.; Tsirlin, A.A.; Ramanujachary, K.V.; Lofland, S.; Croft, M.; Ignatov, A.; Sun, J.; Greenblatt, M. pdf  doi
openurl 
  Title _BiMnFe2O6, a polysynthetically twinned hcp MO structure Type A1 Journal article
  Year 2010 Publication Chemical science Abbreviated Journal Chem Sci  
  Volume 1 Issue 6 Pages 751-762  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract The most efficient use of spatial volume and the lowest potential energies in the metal oxide structures are based on cubic close packing (ccp) or hexagonal close packing (hcp) of anions with cations occupying the interstices. A promising way to tune the composition of close packed oxides and design new compounds is related to fragmenting the parent structure into modules by periodically spaced planar interfaces, such as twin planes at the unit cell scale. The unique crystal chemistry properties of cations with a lone electron pair, such as Bi3+ or Pb2+, when located at interfaces, enables them to act as chemical scissors, to help relieve configurational strain. With this approach, we synthesized a new oxide, BiMnFe2O6, where fragments of the hypothetical hcp oxygen-based MO structure (the NiAs structure type), for the first time, serve as the building modules in a complex transition metal oxide. Mn3+ and Fe3+ ions are randomly distributed in two crystallographically independent sites (M1 and M2). The structure consists of quasi two-dimensional blocks of the 2H hexagonal close packed MO structure cut along the (114) crystal plane of the hcp lattice and stacked along the c axis. The blocks are related by a mirror operation that allows BiMnFe2O6 to be considered as a polysynthetically twinned 2H hcp MO structure. The transition to an AFM state with an incommensurate spin configuration at [similar] 212 K is established by 57Fe Mössbauer spectroscopy, magnetic susceptibility, specific heat and low temperature powder neutron diffraction.  
  Address  
  Corporate Author Thesis  
  Publisher Royal Society of Chemistry Place of Publication Cambridge Editor  
  Language Wos 000283939200013 Publication Date 2010-10-12  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 2041-6520;2041-6539; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 8.668 Times cited 12 Open Access  
  Notes Approved Most recent IF: 8.668; 2010 IF: NA  
  Call Number UA @ lucian @ c:irua:85823 Serial 3517  
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Author Kolchina, L. M.; Lyskov, N.V.; Kuznetsov, A.N.; Kazakov, S.M.; Galin, M.Z.; Meledin, A.; Abakumov, A.M.; Bredikhin, S.I.; Mazo, G.N.; Antipov, E.V. pdf  url
doi  openurl
  Title Evaluation of Ce-doped Pr2CuO4for potential application as a cathode material for solid oxide fuel cells Type A1 Journal article
  Year 2016 Publication RSC advances Abbreviated Journal Rsc Adv  
  Volume 6 Issue 6 Pages 101029-101037  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Pr2−xCexCuO4 (x = 0.05; 0.1; 0.15) samples were synthesized and systematically characterized towards application as a cathode material for solid oxide fuel cells (SOFCs). High-temperature electrical conductivity, thermal expansion, and electrocatalytic activity in the oxygen reduction reaction (ORR) were examined. The electrical conductivity of Pr2−xCexCuO4 oxides demonstrates semiconducting behavior up to 900 °C. Small Ce-doping (2.5 at%) allows an increase in electrical conductivity from 100 to 130 S cm−1 in air at 500–800 °C. DFT calculations revealed that the density of states directly below the Fermi level, comprised mainly of Cu 3d and O 2p states, is significantly affected by atoms in rare earth positions, which might give an indication of a correlation between calculated electronic structures and measured conducting properties. Ce-doping in Pr2−xCexCuO4 slightly increases TEC from 11.9 × 10−6 K−1 for x = 0 to 14.2 × 10−6 K−1 for x = 0.15. Substitution of 2.5% of Pr atoms in Pr2CuO4 by Ce is effective to enhance the electrochemical performance of the material as a SOFC cathode in the ORR (ASR of Pr1.95Ce0.05CuO4 electrode applied on Ce0.9Gd0.1O1.95 electrolyte is 0.39 Ω cm2 at 750 °C in air). The peak power density achieved for the electrolyte-supported fuel cell with the Pr1.95Ce0.05CuO4 cathode is 150 mW cm−2 at 800 °C  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000387427700044 Publication Date 2016-10-19  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 2046-2069 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.108 Times cited 7 Open Access  
  Notes his work was partially supported by Russian Foundation for Basic Research (grant no. 153820247), Skolkovo Institute of Science and Technology (Center of electrochemical energy), and MSUdevelopment Program up to 2020. K.L.M. is grateful to Haldor Topsøe A/S for the financial support. Approved Most recent IF: 3.108  
  Call Number EMAT @ emat @ c:irua:136441 Serial 4296  
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