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Author Erni, R.; Abakumov, A.M.; Rossell, M.D.; Batuk, D.; Tsirlin, A.A.; Nénert, G.; Van Tendeloo, G.
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 1476-1122;1476-4660; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 39.737 Times cited (down) 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 Abakumov, A.M.; Hadermann, J.; Tsirlin, A.A.; Tan, H.; Verbeeck, J.; Zhang, H.; Dikarev, E.V.; Shpanchenko, R.V.; Antipov, E.V.
Title Original close-packed structure and magnetic properties of the Pb4Mn9O20 manganite Type A1 Journal article
Year 2009 Publication Journal of solid state chemistry Abbreviated Journal J Solid State Chem
Volume 182 Issue 8 Pages 2231-2238
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The crystal structure of the Pb4Mn9O20 compound (previously known as Pb0.43MnO2.18) was solved from powder X-ray diffraction, electron diffraction, and high resolution electron microscopy data (S.G. Pnma, a=13.8888(2) Å, b=11.2665(2) Å, c=9.9867(1) Å, RI=0.016, RP=0.047). The structure is based on a 6H (cch)2 close packing of pure oxygen h-type (O16) layers alternating with mixed c-type (Pb4O12) layers. The Mn atoms occupy octahedral interstices formed by the oxygen atoms of the close-packed layers. The MnO6 octahedra share edges within the layers, whereas the octahedra in neighboring layers are linked through corner sharing. The relationship with the closely related Pb3Mn7O15 structure is discussed. Magnetization measurements reveal a peculiar magnetic behavior with a phase transition at 52 K, a small net magnetization below the transition temperature, and a tendency towards spin freezing.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000269066400035 Publication Date 2009-06-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-4596; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.299 Times cited (down) 5 Open Access
Notes The authors are grateful to Christoph Geibel for the help in magnetization measurements. A.Ts. acknowledges MPI CKS for hospitality and financial support during the stay. E.D. thanks the National Science Foundation (CHE-0718900) for financial support. This work was supported by the Russian Foundation of Basic Research (RFBR Grants 07-03-00664-a, 06-03-90168-a and 07-03-00890-a). The authors acknowledge financial support from the European Union under the Framework 6 program under a contract for an Integrated Infrastructure Initiative. Reference 026019 ESTEEM. Approved Most recent IF: 2.299; 2009 IF: 2.340
Call Number UA @ lucian @ c:irua:78935UA @ admin @ c:irua:78935 Serial 2529
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Author Tsirlin, A.A.; Abakumov, A.M.; Ritter, C.; Henry, P.F.; Janson, O.; Rosner, H.
Title Short-range order of Br and three-dimensional magnetism in (CuBr)LaNb2O7 Type A1 Journal article
Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 85 Issue 21 Pages 214427
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We present a comprehensive study of the crystal structure, magnetic structure, and microscopic magnetic model of (CuBr)LaNb2O7, the Br analog of the spin-gap quantum magnet (CuCl) LaNb2O7. Despite similar crystal structures and spin lattices, the magnetic behavior and even peculiarities of the atomic arrangement in the Cl and Br compounds are very different. The high- resolution x-ray and neutron data reveal a split position of Br atoms in (CuBr) LaNb2O7. This splitting originates from two possible configurations developed by [CuBr] zigzag ribbons. While the Br atoms are locally ordered in the ab plane, their arrangement along the c direction remains partially disordered. The predominant and energetically more favorable configuration features an additional doubling of the c lattice parameter that was not observed in (CuCl) LaNb2O7. (CuBr) LaNb2O7 undergoes long-range antiferromagnetic ordering at T-N = 32 K, which is nearly 70% of the leading exchange coupling J4 similar or equal to 48 K. The Br compound does not show any experimental signatures of low-dimensional magnetism because the underlying spin lattice is three-dimensional. The coupling along the c direction is comparable to the couplings in the ab plane, even though the shortest Cu-Cu distance along c (11.69 angstrom) is three times larger than nearest-neighbor distances in the ab plane (3.55 angstrom). The stripe antiferromagnetic long-range order featuring columns of parallel spins in the ab plane and antiparallel spins along c is verified experimentally and confirmed by the microscopic analysis.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000305557600002 Publication Date 2012-06-22
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 (down) 5 Open Access
Notes Approved Most recent IF: 3.836; 2012 IF: 3.767
Call Number UA @ lucian @ c:irua:100289 Serial 2998
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Author Blandy, J.N.; Abakumov, A.M.; Christensen, K.E.; Hadermann, J.; Adamson, P.; Cassidy, S.J.; Ramos, S.; Free, D.G.; Cohen, H.; Woodruff, D.N.; Thompson, A.L.; Clarke, S.J.;
Title Soft chemical control of the crystal and magnetic structure of a layered mixed valent manganite oxide sulfide Type A1 Journal article
Year 2015 Publication APL materials Abbreviated Journal Apl Mater
Volume 3 Issue 3 Pages 041520
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Oxidative deintercalation of copper ions from the sulfide layers of the layered mixed-valent manganite oxide sulfide Sr2MnO2Cu1.5S2 results in control of the copper-vacancy modulated superstructure and the ordered arrangement of magnetic moments carried by the manganese ions. This soft chemistry enables control of the structures and properties of these complex materials which complement mixed-valent perovskite and perovskite-related transition metal oxides. (C) 2015 Author(s).
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000353828400027 Publication Date 2015-04-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2166-532X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.335 Times cited (down) 5 Open Access
Notes Approved Most recent IF: 4.335; 2015 IF: NA
Call Number c:irua:126021 Serial 3049
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Author Alekseeva, A.M.; Abakumov, A.M.; Leither-Jasper, A.; Schnelle, W.; Prots, Y.; Van Tendeloo, G.; Antipov, E.V.; Grin, Y.
Title Spatial separation of covalent, ionic, and metallic interactions in Mg11Rh18B8 and Mg3Rh5B3 Type A1 Journal article
Year 2013 Publication Chemistry: a European journal Abbreviated Journal Chem-Eur J
Volume 19 Issue 52 Pages 17860-17870
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The crystal structures of Mg11Rh18B8 and Mg3Rh5B3 have been investigated by using single-crystal X-ray diffraction. Mg11Rh18B8: space group P4/mbm; a=17.9949(7), c=2.9271(1)angstrom; Z=2. Mg3Rh5B3: space group Pmma; a=8.450(2), b=2.8644(6), c=11.602(2)angstrom; Z=2. Both crystal structures are characterized by trigonal prismatic coordination of the boron atoms by rhodium atoms. The [BRh6] trigonal prisms form arrangements with different connectivity patterns. Analysis of the chemical bonding by means of the electron-localizability/electron-density approach reveals covalent BRh interactions in these arrangements and the formation of BRh polyanions. The magnesium atoms that are located inside the polyanions interact ionically with their environment, whereas, in the structure parts, which are mainly formed by Mg and Rh atoms, multicenter (metallic) interactions are observed. Diamagnetic behavior and metallic electron transport of the Mg11Rh18B8 and Mg3Rh5B3 phases are in agreement with the bonding picture and the band structure.
Address
Corporate Author Thesis
Publisher Place of Publication Weinheim Editor
Language Wos 000328531000028 Publication Date 2013-12-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0947-6539; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 5.317 Times cited (down) 5 Open Access
Notes Approved Most recent IF: 5.317; 2013 IF: 5.696
Call Number UA @ lucian @ c:irua:113697 Serial 3064
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Author Napolsky, P.S.; Drozhzhin, O.A.; Istomin, S.Y.; Kazakov, S.M.; Antipov, E.V.; Galeeva, A.V.; Gippius, A.A.; Svensson, G.; Abakumov, A.M.; Van Tendeloo, G.
Title Structure and high-temperature properties of the (Sr,Ca,Y)(Co,Mn)O3-y perovskites – perspective cathode materials for IT-SOFC Type A1 Journal article
Year 2012 Publication Journal of solid state chemistry Abbreviated Journal J Solid State Chem
Volume 192 Issue Pages 186-194
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Oxygen deficient perovskites Sr0.75Y0.25Co1-xMnxO3-y, x=0.5 and 0.75, were prepared by using the citrate route at 1373-1573 K for 48 h. The cubic Pm-3m perovskite structure for x=0.5 was confirmed by electron diffraction study and refined using neutron powder diffraction (NPD) data. For x=0.75, the superstructure corresponding to a=root 2 x a(per), b=2 x a(per), c=root 2 x a(per) (a(0)b(-)b(-) tilt system, space group Imma) was revealed by electron diffraction. The solid solution Sr0.75-xCaxY0.25Co0.25Mn0.75O3-y, 0.1 <= x <= 0.6 and compound Ca0.75Y0.25Mn0.85Co0.15O2.92 were prepared in air at 1573 K for 48 h. The crystal structure of Ca0.75Y0.25Mn0.85Co0.15O2.92 was refined using NPD data (S.G. Pnma, a=5.36595(4), b=7.5091(6), c=5.2992(4) angstrom, R-p=0.057, R-wp=0.056, chi(2)=4.26). High-temperature thermal expansion properties of the prepared compounds were studied in air using both dilatometry and high-temperature X-ray powder diffraction data (HTXRPD). They expanding non-linearly at 298-1073 K due to the loss of oxygen at high temperatures. Calculated average thermal expansion coefficients (TECs) for Sr0.75Y0.25Co1-xMnxO3-y, x=0.5, 0.75 and Ca0.75Y0.25Mn0.85Co0.15O2.92(1) are 15.5, 15.1, and 13.8 ppm K-1, respectively. Anisotropy of the thermal expansion along different unit cell axes was observed for Sr0.15Ca0.6Y0.25Co0.25Mn0.75O3-y, and Ca0.75Y0.25Mn0.85Co0.15O2.92. Conductivity of Sr0.75Y0.25Co1-xMnxO3-y, x=0.5 and 0.75 increases with the temperature reaching 110 S/cm for x=0.5 and 44 S/cm for x=0.75 at 1173 K. Samples of Sr0.75-xCaxY0.25Co0.25Mn0.75O3-y, 0.1 <= y <= 0.6 were found to be n-type conductors at room temperature with the similar temperature dependence of the conductivity and demonstrated the increase of the sigma value from similar to 1 to similar to 50 S/cm as the temperature increases from 300 to 1173 K. Their conductivity is described in terms of the small polaron charge transport with the activation energy (E-p) increasing from 340 to 430 meV with an increase of the calcium content from x=0 to x=0.6. (C) 2012 Elsevier Inc. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000307028300030 Publication Date 2012-03-31
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-4596; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.299 Times cited (down) 5 Open Access
Notes Approved Most recent IF: 2.299; 2012 IF: 2.040
Call Number UA @ lucian @ c:irua:101119 Serial 3279
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Author Mordvinova, N.; Emelin, P.; Vinokurov, A.; Dorofeev, S.; Abakumov, A.; Kuznetsova, T.
Title Surface processes during purification of InP quantum dots Type A1 Journal article
Year 2014 Publication Beilstein journal of nanotechnology Abbreviated Journal Beilstein J Nanotech
Volume 5 Issue Pages 1220-1225
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Recently, a new simple and fast method for the synthesis of InP quantum dots by using phosphine as phosphorous precursor and myristic acid as surface stabilizer was reported. Purification after synthesis is necessary to obtain samples with good optical properties. Two methods of purification were compared and the surface processes which occur during purification were studied. Traditional precipitation with acetone is accompanied by a small increase in photoluminescence. It occurs that during the purification the hydrolysis of the indium precursor takes place, which leads to a better surface passivation. The electrophoretic purification technique does not increase luminescence efficiency but yields very pure quantum dots in only a few minutes. Additionally, the formation of In(OH)(3) during the low temperature synthesis was explained. Purification of quantum dots is a very significant part of post-synthetical treatment that determines the properties of the material. But this subject is not sufficiently discussed in the literature. The paper is devoted to the processes that occur at the surface of quantum dots during purification. A new method of purification, electrophoresis, is investigated and described in particular.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000339912400002 Publication Date 2014-08-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2190-4286; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.127 Times cited (down) 5 Open Access
Notes Approved Most recent IF: 3.127; 2014 IF: 2.670
Call Number UA @ lucian @ c:irua:118748 Serial 3397
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Author Abakumov, A.M.; Shpanchenko, R.V.; Antipov, E.V.; Kopnin, E.M.; Capponi, J.J.; Marezio, M.; Lebedev, O.I.; Van Tendeloo, G.; Amelinckx, S.
Title Synthesis and structural study of Pb2Re2O7-x pyrochlores Type A1 Journal article
Year 1998 Publication Journal of solid state chemistry Abbreviated Journal J Solid State Chem
Volume 138 Issue Pages 220-225
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000075369600005 Publication Date 2002-10-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-4596; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.299 Times cited (down) 5 Open Access
Notes Approved Most recent IF: 2.299; 1998 IF: 1.432
Call Number UA @ lucian @ c:irua:25665 Serial 3439
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Author Mandal, T.K.; Abakumov, A.M.; Hadermann, J.; Van Tendeloo, G.; Croft, M.; Greenblatt, M.
Title Synthesis, crystal structure, and magnetic properties of Srl.31Co0.63Mn0.3703: a reivative of the incommensurate composite hexagonal perovskite structure Type A1 Journal article
Year 2007 Publication Chemistry of materials Abbreviated Journal Chem Mater
Volume 19 Issue 25 Pages 6158-6167
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000251422000019 Publication Date 2007-11-13
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 (down) 5 Open Access
Notes Approved Most recent IF: 9.466; 2007 IF: 4.883
Call Number UA @ lucian @ c:irua:67597 Serial 3449
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Author Abakumov, A.M.; Hadermann, J.; Kalyuzhnaya, A.S.; Rozova, M.G.; Mikheev, M.G.; Van Tendeloo, G.; Antipov, E.V.
Title Ca6.3Mn3Ga4.4Al1.3O18: a novel complex oxide with 3D tetrahedral framework Type A1 Journal article
Year 2005 Publication Journal of solid state chemistry Abbreviated Journal J Solid State Chem
Volume 178 Issue 10 Pages 3137-3144
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000232418200022 Publication Date 2005-08-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-4596; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.299 Times cited (down) 5 Open Access
Notes Iap V-1; Rfbr; Intas – Ysf Approved Most recent IF: 2.299; 2005 IF: 1.725
Call Number UA @ lucian @ c:irua:55030 Serial 3520
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Author Charkin, D.O.; Akinfiev, V.S.; Alekseeva, A.M.; Batuk, M.; Abakumov, A.M.; Kazakov, S.M.
Title Synthesis and cation distribution in the new bismuth oxyhalides with the Sillen-Aurivillius intergrowth structures Type A1 Journal article
Year 2015 Publication Journal of the Chemical Society : Dalton transactions Abbreviated Journal Dalton T
Volume 44 Issue 44 Pages 20568-20576
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract About 20 new compounds with the Sillen-Aurivillius intergrowth structure, (MeMeBi3Nb2O11X)-Me-1-Bi-2 (Me-1 = Pb, Sr, Ba; Me-2 = Ca, Sr, Ba; X = Cl, Br, I), have been prepared. They are composed of stacking of [ANb(2)O(7)] perovskite blocks, fluorite-type [M2O2] blocks and halogen sheets. The cation distribution between the fluorite and perovskite layers has been studied for Ba2Bi3Nb2O11I, Ca1.25Sr0.75Bi3Nb2O11Cl, BaCaBi3Nb2O11Br and Sr2Bi3Nb2O11Cl. The smaller Me cations tend to reside in the perovskite block while the larger ones are situated in the fluorite-type block. The distribution of the elements was confirmed for BaCaBi3Nb2O11Br using energy dispersive X-ray analysis combined with scanning transmission electron microscopy (STEM-EDX). An electron diffraction study of this compound reveals a local symmetry lowering caused by weakly correlated rotation of NbO6 octahedra. Based on our findings, we suggest a new stability criterion for mixed-layer structures, which is that net charges of any two consecutive layers do not compensate for each other and only the whole layer sequence is electroneutral.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000365411500036 Publication Date 2015-10-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0300-9246; 1477-9226; 1472-7773 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.029 Times cited (down) 5 Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:130330 Serial 4256
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Author Semkina, A.S.; Abakumov, M.A.; Abakumov, A.M.; Nukolova, N.V.; Chekhonin, V.P.
Title Relationship between the Size of Magnetic Nanoparticles and Efficiency of MRT Imaging of Cerebral Glioma in Rats Type A1 Journal article
Year 2016 Publication Bulletin of experimental biology and medicine Abbreviated Journal B Exp Biol Med+
Volume 161 Issue 2 Pages 292-295
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract BSA-coated Fe3O4 nanoparticles with different hydrodynamic diameters (36 +/- 4 and 85 +/- 10 nm) were synthesized, zeta potential and T2 relaxivity were determined, and their morphology was studied by transmission electron microscopy. Studies on rats with experimental glioma C6 showed that smaller nanoparticles more effectively accumulated in the tumor and circulated longer in brain vessels. Optimization of the hydrodynamic diameter improves the efficiency of MRT contrast agent.
Address
Corporate Author Thesis
Publisher Place of Publication New York Editor
Language Wos 000380118500022 Publication Date 2016-07-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0007-4888 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 0.456 Times cited (down) 5 Open Access
Notes Approved Most recent IF: 0.456
Call Number UA @ lucian @ c:irua:144707 Serial 4684
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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.
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 1463-9076; 1463-9084 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.123 Times cited (down) 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.; Abakumov, A.M.; Van Rompaey, S.; Mankevich, A.S.; Korsakov, I.E.
Title Comment on ALaMn2O6-y (A = K, Rb): novel ferromagnetic manganites exhibiting negative giant magnetoresistance Type Editorial
Year 2009 Publication Chemistry of materials Abbreviated Journal Chem Mater
Volume 21 Issue 9 Pages 2000-2001
Keywords Editorial; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000265781000036 Publication Date 2009-04-14
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 (down) 4 Open Access
Notes Approved Most recent IF: 9.466; 2009 IF: 5.368
Call Number UA @ lucian @ c:irua:77055 Serial 411
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Author Shpanchenko, R.V.; Chyornaya, V.V.; Abakumov, A.M.; Antipov, E.V.; Hadermann, J.; Van Tendeloo, G.; Kaul, E.; Geibel, C.; Sheptyakov, D.; Balagurov, A.M.
Title Crystal structure and magnetic properties of novel reduced V(IV)-based oxide Pb2V5O12 Type A1 Journal article
Year 2001 Publication Zeitschrift für anorganische und allgemeine Chemie Abbreviated Journal Z Anorg Allg Chem
Volume 627 Issue Pages 2143-2150
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Leipzig Editor
Language Wos 000171339000023 Publication Date 2002-08-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0044-2313;1521-3749; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.144 Times cited (down) 4 Open Access
Notes Approved Most recent IF: 1.144; 2001 IF: 1.165
Call Number UA @ lucian @ c:irua:36048 Serial 560
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Author Rossell, M.D.; Abakumov, A.M.; Ramasse, Q.M.; Erni, R.
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 1936-0851;1936-086X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 13.942 Times cited (down) 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 Serov, T.V.; Dombrovski, E.N.; Ardashnikova, E.I.; Dolgikh, V.A.; el Omari, M.; el Omari, M.; Abaouz, A.; Senegas, J.; Chaban, N.G.; Abakumov, A.M.; Van Tendeloo, G.
Title Fluorite-like phases in the BaF2-BiF3-Bi2O3 system-synthesis, conductivity and defect clustering Type A1 Journal article
Year 2005 Publication Materials research bulletin Abbreviated Journal Mater Res Bull
Volume 40 Issue 5 Pages 821-830
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000229376500012 Publication Date 2005-03-01
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0025-5408; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.446 Times cited (down) 4 Open Access
Notes Iap V-1 Approved Most recent IF: 2.446; 2005 IF: 1.380
Call Number UA @ lucian @ c:irua:54838 Serial 1240
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Author Prituzhalov, V.A.; Abakumov, A.M.; Ardashnikova, E.I.; Dolgikh, V.A.; Van Tendeloo, G.
Title :Ba2.1Bi0.9(O, F)6.8-\delta: a new ordered anion-excess fluorite Type A1 Journal article
Year 2007 Publication Materials research bulletin Abbreviated Journal Mater Res Bull
Volume 42 Issue 5 Pages 861-869
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000245842600010 Publication Date 2006-10-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0025-5408; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.446 Times cited (down) 4 Open Access
Notes Approved Most recent IF: 2.446; 2007 IF: 1.484
Call Number UA @ lucian @ c:irua:64724 Serial 3515
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Author Batuk, M.; Batuk, D.; Abakumov, A.M.; Hadermann, J.
Title Pb5Fe3TiO11Cl : a rare example of Ti(IV) in a square pyramidal oxygen coordination Type A1 Journal article
Year 2014 Publication Journal of solid state chemistry Abbreviated Journal J Solid State Chem
Volume 215 Issue Pages 245-252
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract A new oxychloride Pb5Fe3TiO11Cl has been synthesized using the solid state method. Its crystal and magnetic structure was investigated in the 1.5550 K temperature range using electron diffraction, high angle annular dark field scanning transmission electron microscopy, atomic resolution energy dispersive X-ray spectroscopy, neutron and X-ray powder diffraction. At room temperature Pb5Fe3TiO11Cl crystallizes in the P4/mmm space group with the unit cell parameters a=3.91803(3) Å and c=19.3345(2) Å. Pb5Fe3TiO11Cl is a new n=4 member of the oxychloride perovskite-based homologous series An+1BnO3n−1Cl. The structure is built of truncated Pb3Fe3TiO11 quadruple perovskite blocks separated by CsCl-type Pb2Cl slabs. The perovskite blocks consist of two layers of (Fe,Ti)O6 octahedra sandwiched between two layers of (Fe,Ti)O5 square pyramids. The Ti4+ cations are preferentially located in the octahedral layers, however, the presence of a noticeable amount of Ti4+ in a five-fold coordination environment has been undoubtedly proven using neutron powder diffraction and atomic resolution compositional mapping. Pb5Fe3TiO11Cl is antiferromagnetically ordered below 450(10) K. The ordered Fe magnetic moments at 1.5 K are 4.06(4) μB and 3.86(5) μB on the octahedral and square-pyramidal sites, respectively.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000336891300037 Publication Date 2014-04-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-4596; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.299 Times cited (down) 4 Open Access
Notes Fwo G.0184.09n. Approved Most recent IF: 2.299; 2014 IF: 2.133
Call Number UA @ lucian @ c:irua:117066 Serial 3551
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Author Abakumov, A.M.; Li, C.; Boev, A.; Aksyonov, D.A.; Savina, A.A.; Abakumova, T.A.; Van Tendeloo, G.; Bals, S.
Title Grain boundaries as a diffusion-limiting factor in lithium-rich NMC cathodes for high-energy lithium-ion batteries Type A1 Journal article
Year 2021 Publication ACS applied energy materials Abbreviated Journal
Volume 4 Issue 7 Pages 6777-6786
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract High-energy lithium-rich layered transition metal oxides are capable of delivering record electrochemical capacity and energy density as positive electrodes for Li-ion batteries. Their electrochemical behavior is extremely complex due to sophisticated interplay between crystal structure, electronic structure, and defect structure. Here we unravel an extra level of this complexity by revealing that the most typical representative Li1.2Ni0.13Mn0.54Co0.13O2 material, prepared by a conventional coprecipitation technique with Na2CO3 as a precipitating agent, contains abundant coherent (001) grain boundaries with a Na-enriched P2-structured block due to segregation of the residual sodium traces. The trigonal prismatic oxygen coordination of Na triggers multiple nanoscale twinning, giving rise to incoherent (104) boundaries. The cationic layers at the (001) grain boundaries are filled with transition metal cations being Mn-depleted and Co-enriched; this makes them virtually not permeable for the Li+ cations, and therefore they negatively influence the Li diffusion in and out of the spherical agglomerates. These results demonstrate that besides the mechanisms intrinsic to the crystal and electronic structure of Li-rich cathodes, their rate capability might also be depreciated by peculiar microstructural aspects. Dedicated engineering of grain boundaries opens a way for improving inherently sluggish kinetics of these materials.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000678382900042 Publication Date 2021-07-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2574-0962 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited (down) 4 Open Access OpenAccess
Notes We thank Dr. M. V. Berekchiian (MSU) for assisting in ICPMS measurements. We acknowledge Russian Science Foundation (Grant 20-43-01012) and Research Foundation Flanders (FWO Vlaanderen, Project No. G0F1320N) for financial support. Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:180556 Serial 6841
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Author Kirsanova, M.A.; Mori, T.; Maruyama, S.; Abakumov, A.M.; Van Tendeloo, G.; Olenev, A.; Shevelkov, A.V.
Title Cationic clathrate of type-III Ge172-xPxTey (y\approx21,5, x\approx2y) : synthesis, crystal structure and thermoelectric properties Type A1 Journal article
Year 2013 Publication Inorganic chemistry Abbreviated Journal Inorg Chem
Volume 52 Issue 14 Pages 8272-8279
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract A first germanium-based cationic clathrate of type-III, Ge129.3P42.7Te21.53, was synthesized and structurally characterized (space group P42/mnm, a = 19.948(3) Å, c = 10.440(2) Å, Z = 1). In its crystal structure, germanium and phosphorus atoms form three types of polyhedral cages centered with Te atoms. The polyhedra share pentagonal and hexagonal faces to form a 3D framework. Despite the complexity of the crystal structure, the Ge129.3P42.7Te21.53 composition corresponds to the Zintl counting scheme with a good accuracy. Ge129.3P42.7Te21.53 demonstrates semiconducting/insulating behavior of electric resistivity, high positive Seebeck coefficient (500 μV K1 at 300 K), and low thermal conductivity (<0.92 W m1 K1) within the measured temperature range.
Address
Corporate Author Thesis
Publisher Place of Publication Easton, Pa Editor
Language Wos 000322087100052 Publication Date 2013-06-26
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 (down) 3 Open Access
Notes Countatoms Approved Most recent IF: 4.857; 2013 IF: 4.794
Call Number UA @ lucian @ c:irua:109214 Serial 301
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Author Batuk, D.; de Dobbelaere, C.; Tsirlin, A.A.; Abakumov, A.M.; Hardy, A.; van Bael, M.K.; Greenblatt, M.; Hadermann, J.
Title Crystal structure and magnetic properties of the Cr-doped spiral antiferromagnet BiMnFe2O6 Type A1 Journal article
Year 2013 Publication Materials research bulletin Abbreviated Journal Mater Res Bull
Volume 48 Issue 9 Pages 2993-2997
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We report the Cr3+ for Mn3+ substitution in the BiMnFe2O6 structure. The BiCrxMn1-xFe2O6 solid solution is obtained by the solution-gel synthesis technique for the x values up to 0.3. The crystal structure investigation using a combination of X-ray powder diffraction and transmission electron microscopy demonstrates that the compounds retain the parent BiMnFe2O6 structure (for x = 0.3, a = 5.02010(6)angstrom, b = 7.06594(7)angstrom, c = 12.6174(1)angstrom, S.G. Pbcm, R-1 = 0.036, R-p = 0.011) with only a slight decrease in the cell parameters associated with the Cr3+ for Mn3+ substitution. Magnetic susceptibility measurements suggest strong similarities in the magnetic behavior of BiCrxMn1-xFe2O6 (x = 0.2; 0.3) and parent BiMnFe2O6. Only T-N slightly decreases upon Cr doping that indicates a very subtle influence of Cr3+ cations on the magnetic properties at the available substitution rates. (C) 2013 Elsevier Ltd. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000322354000002 Publication Date 2013-04-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0025-5408; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.446 Times cited (down) 3 Open Access
Notes Fwo Approved Most recent IF: 2.446; 2013 IF: 1.968
Call Number UA @ lucian @ c:irua:109755 Serial 561
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Author Vassiliev, S.Y.; Laurinavichute, V.K.; Abakumov, A.M.; Govorov, V.A.; Bendovskii, E.B.; Turner, S.; Filatov, A.Y.; Tarasovskii, V.P.; Borzenko, A.G.; Alekseeva, A.M.; Antipov, E.V.
Title Microstructural aspects of the degradation behavior of SnO2-based anodes for aluminum electrolysis Type A1 Journal article
Year 2010 Publication Journal of the electrochemical society Abbreviated Journal J Electrochem Soc
Volume 157 Issue 5 Pages C178-C186
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The performance of SnO2 ceramic anodes doped with copper and antimony oxides was examined in cryolite alumina melts under anodic polarization at different cryolite ratios, temperatures, times, and current densities. The corroded part consists of a narrow strong corrosion zone at the anode surface with damage of the intergrain contacts and a large increase in porosity, a wider moderate corrosion zone with a smaller porosity increase, and a Cu depletion zone, where the ceramic retains its initial microstructure and a slight porosity increase occurs due to the removal of the Cu-rich inclusions. Mechanical destruction of the anode was never observed in the 10100 h tests. A microstructural model of the ceramic was suggested, consisting of grains with an Sb-doped SnO2 grain core surrounded by an ~200 to 500 nm grain shell where SnO2 was simultaneously doped with Sb and Mn+ (M=Cu2+,Fe3+,Al3+). The grains were separated by a few nanometers thick Cu-enriched grain boundaries. Different secondary charge carrier (holes) concentrations and electric conductivities in the grain core and grain shell result in a higher current density at the intergrain regions that leads to their profound degradation, especially in the low temperature acidic melt.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000276555300037 Publication Date 2010-04-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0013-4651; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.259 Times cited (down) 3 Open Access
Notes Approved Most recent IF: 3.259; 2010 IF: 2.427
Call Number UA @ lucian @ c:irua:82260 Serial 2040
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Author Kazin, P.E.; Abakumov, A.M.; Zaytsev, D.D.; Tretyakov, Y.D.; Khasanova, N.R.; Van Tendeloo, G.; Jansen, M.
Title Synthesis and crystal structure of Sr2ScBiO6 Type A1 Journal article
Year 2001 Publication Journal of solid state chemistry Abbreviated Journal J Solid State Chem
Volume 162 Issue 1 Pages 142-147
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000172586400019 Publication Date 2002-09-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-4596; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.299 Times cited (down) 3 Open Access
Notes Approved Most recent IF: 2.299; 2001 IF: 1.614
Call Number UA @ lucian @ c:irua:54710 Serial 3426
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Author Abakumov, A.M.; Rozova, M.G.; Chizhov, P.S.; Antipov, E.V.; Hadermann, J.; Van Tendeloo, G.
Title Synthesis and crystal structure of the novel Pb5Sb2MnO11 compound Type A1 Journal article
Year 2004 Publication Journal of solid state chemistry Abbreviated Journal J Solid State Chem
Volume 177 Issue Pages 2855-2861
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000223145500030 Publication Date 2004-08-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-4596; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.299 Times cited (down) 3 Open Access
Notes Approved Most recent IF: 2.299; 2004 IF: 1.815
Call Number UA @ lucian @ c:irua:47316 Serial 3428
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Author Batuk, D.; Tsirlin, A.A.; Filimonov, D.S.; Zakharov, K.V.; Volkova, O.S.; Vasiliev, A.; Hadermann, J.; Abakumov, A.M.
Title Bi(3n+1)Ti7Fe(3n-3)O(9n+11) Homologous Series: Slicing Perovskite Structure with Planar Interfaces Containing Anatase-like Chains Type A1 Journal article
Year 2016 Publication Inorganic chemistry Abbreviated Journal Inorg Chem
Volume 55 Issue 55 Pages 1245-1257
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The n = 3-6 members of a new perovskite-based homologous series Bi(3n+1)Ti7Fe(3n-3)O(9n+11) are reported. The crystal structure of the n = 3 Bi10Ti7Fe6O38 member is refined using a combination of X-ray and neutron powder diffraction data (a = 11.8511(2) A, b = 3.85076(4) A, c = 33.0722(6) A, S.G. Immm), unveiling the partially ordered distribution of Ti(4+) and Fe(3+) cations and indicating the presence of static random displacements of the Bi and O atoms. All Bi(3n+1)Ti7Fe(3n-3)O(9n+11) structures are composed of perovskite blocks separated by translational interfaces parallel to the (001)p perovskite planes. The thickness of the perovskite blocks increases with n, while the atomic arrangement at the interfaces remains the same. The interfaces comprise chains of double edge-sharing (Fe,Ti)O6 octahedra connected to the octahedra of the perovskite blocks by sharing edges and corners. This configuration shifts the adjacent perovskite blocks relative to each other over a vector (1/2)[110]p and creates S-shaped tunnels along the [010] direction. The tunnels accommodate double columns of the Bi(3+) cations, which stabilize the interfaces owing to the stereochemical activity of their lone electron pairs. The Bi(3n+1)Ti7Fe(3n-3)O(9n+11) structures can be formally considered either as intergrowths of perovskite modules and polysynthetically twinned modules of the Bi2Ti4O11 structure or as intergrowths of the 2D perovskite and 1D anatase fragments. Transmission electron microscopy (TEM) on Bi10Ti7Fe6O38 reveals that static atomic displacements of Bi and O inside the perovskite blocks are not completely random; they are cooperative, yet only short-range ordered. According to TEM, the interfaces can be laterally shifted with respect to each other over +/-1/3a, introducing an additional degree of disorder. Bi10Ti7Fe6O38 is paramagnetic in the 1.5-1000 K temperature range due to dilution of the magnetic Fe(3+) cations with nonmagnetic Ti(4+). The n = 3, 4 compounds demonstrate a high dielectric constant of 70-165 at room temperature.
Address Center for Electrochemical Energy Storage, Skolkovo Institute of Science and Technology , Nobelya str. 3, 143026 Moscow, Russia
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Wos 000369356800031 Publication Date 2016-01-09
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0020-1669 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.857 Times cited (down) 3 Open Access
Notes We are grateful to the Laboratory for Neutron Scattering and Imaging of Paul Scherrer Institut (LNS PSI, Villigen, Switzerland) for granting beam time at the HRPT diffrac- tometer and to Dr. Denis Sheptyakov for the technical support during the experiment. We are also grateful to Valery Verchenko for his help with magnetization measurements. The work has been supported by the Russian Science Foundation (grant 14-13-00680). A.A.T. was partly supported by the Federal Ministry for Education and Science through a Sofja Kovalevskaya Award of Alexander von Humboldt Foundation. Approved Most recent IF: 4.857
Call Number c:irua:132247 Serial 4073
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Author Batuk, D.; Batuk, M.; Tsirlin, A.A.; Hadermann, J.; Abakumov, A.M.
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 1433-7851 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 11.994 Times cited (down) 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 Batuk, D.; Batuk, M.; Filimonov, D.S.; Zakharov, K.V.; Volkova, O.S.; Vasiliev, A.N.; Tyablikov, O.A.; Hadermann, J.; Abakumov, A.M.
Title Crystal Structure, Defects, Magnetic and Dielectric Properties of the Layered Bi3n+1Ti7Fe3n-3,O9n+11 Perovskite-Anatase lntergrowths Type A1 Journal article
Year 2017 Publication Inorganic chemistry Abbreviated Journal Inorg Chem
Volume 56 Issue 56 Pages 931-942
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The Bi3n+1Ti7Fe3n-3,O9n+11 materials are built of (001)(p) plane parallel perovskite blocks with a thickness of n (Ti,Fe)O-6 octahedra, separated by periodic translational interfaces. The interfaces are based on anatase-like chains of edge -sharing (Ti,Fe)O-6 octahedra. Together with the octahedra of the perovskite blocks, they create S-shaped tunnels stabilized by lone pair Bi3+ cations. In this work, the structure of the n = 4-6 Bi3n+1Ti7Fe3n-3,O9n+11 homologues is analyzed in detail using advanced transmission electron microscopy, powder X-ray diffraction, and Mossbauer spectroscopy. The connectivity of the anatase-like chains to the perovskite blocks results in,a 3ap periodicity along the interfaces, so that they can be located either on top of each other or with shifts of +/- a(p) along [100](p). The ordered arrangement of the interfaces gives rise to orthorhombic Immm and monoclinic A2/m polymorphs with the unit cell parameters a = 3a(p), b = b(p), c = 2(n + 1)c(p) and a = 3a(p), b = b(p), c = 2(n + 1)c(p) – a(p), respectively. While the n = 3 compound is orthorhombic, the monoclinic modification is more favorable in higher homologues. The Bi3n+1Ti7Fe3n-3,O9n+11 structures demonstrate intricate patterns of atomic displacements in the perovskite blocks, which are supported by the stereochemical activity of the Bi3+ cations. These patterns are coupled to the cationic coordination of the oxygen atoms in the (Ti,Fe)O-2 layers at the border of the perovskite blocks. The coupling is strong in the 1/ = 3, 4 homologues, but gradually reduces with the increasing thickness of the perovskite blocks, so that, in the n = 6 compound, the dominant mode of atomic displacements is aligned along the interface planes. The displacements in the adjacent perovskite blocks tend to order antiparallel, resulting in an overall antipolar structure. The Bi3n+1Ti7Fe3n-3,O9n+11 materials demonstrate an unusual diversity of structure defects. The n = 4-6 homologues are robust antiferromagnets below T-N = 135, 220, and 295 K, respectively. They show a high dielectric constant that weakly increases with temperature and is relatively insensitive to the Ti/Fe ratio.
Address
Corporate Author Thesis
Publisher Place of Publication Easton, Pa Editor
Language Wos 000392262400029 Publication Date 2016-12-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0020-1669 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.857 Times cited (down) 3 Open Access Not_Open_Access
Notes ; The work was supported by the Russian Science Foundation (grant 14-13-00680). ; Approved Most recent IF: 4.857
Call Number UA @ lucian @ c:irua:141471 Serial 4495
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Author Weber, D.; Huber, M.; Gorelik, T.E.; Abakumov, A.M.; Becker, N.; Niehaus, O.; Schwickert, C.; Culver, S.P.; Boysen, H.; Senyshyn, A.; Poettgen, R.; Dronskowski, R.; Ressler, T.; Kolb, U.; Lerch, M.
Title Molybdenum oxide nitrides of the Mo2(O,N,\square)5 type : on the way to Mo2O5 Type A1 Journal article
Year 2017 Publication Inorganic chemistry Abbreviated Journal Inorg Chem
Volume 56 Issue 15 Pages 8782-8792
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Blue-colored molybdenum oxide nitrides of the Mo-2(O,N,square)(5) type were synthesized by direct nitridation of commercially available molybdenum trioxide with a mixture of gaseous ammonia and oxygen. Chemical composition, crystal structure, and stability of the obtained and hitherto unknown compounds are studied extensively. The average oxidation state of +5 for molybdenum is proven by Mo K near-edge X-ray absorption spectroscopy; the magnetic behavior is in agreement with compounds exhibiting (MoO6)-O-v units. The new materials are stable up to similar to 773 K in an inert gas atmosphere. At higher temperatures, decomposition is observed. X-ray and neutron powder diffraction, electron diffraction, and high-resolution transmission electron microscopy reveal the structure to be related to VNb9O24.9-type phases, however, with severe disorder hampering full structure determination. Still, the results demonstrate the possibility of a future synthesis of the potential binary oxide Mo2O5. On the basis of these findings, a tentative suggestion on the crystal structure of the potential compound Mo2O5, backed by electronic-structure and phonon calculations from first principles, is given.
Address
Corporate Author Thesis
Publisher Place of Publication Easton, Pa Editor
Language Wos 000407405500026 Publication Date 2017-07-17
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0020-1669 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.857 Times cited (down) 3 Open Access Not_Open_Access
Notes ; Financial support from the Deutsche Forschungsgemeinschaft (SPP 1415, LE 781/ 11-1, DR 342/22-2) is gratefully acknowledged. The authors are grateful to J. Barthel, Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons Julich, Germany, for STEM image simulations. This work was further supported by Diamond Light Source (beamtime awards EE13560) within beamtime proposal SP13560. The Hamburg Synchrotron Radiation Laboratory, HASYLAB, and the FRM II, Garching, are acknowledged for providing beamtime. ; Approved Most recent IF: 4.857
Call Number UA @ lucian @ c:irua:145727 Serial 4744
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Author Savina, A.A.; Saiutina, V.V.; Morozov, A.V.; Boev, A.O.; Aksyonov, D.A.; Dejoie, C.; Batuk, M.; Bals, S.; Hadermann, J.; Abakumov, A.M.
Title Chemistry, local molybdenum clustering, and electrochemistry in the Li2+xMo1-xO3 solid solutions Type A1 Journal article
Year 2022 Publication Inorganic chemistry Abbreviated Journal Inorg Chem
Volume 61 Issue 14 Pages 5637-5652
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract A broad range of cationic nonstoichiometry has been demonstratedfor the Li-rich layered rock-salt-type oxide Li2MoO3, which has generally been considered as a phase with a well-defined chemical composition. Li2+xMo1-xO3(-0.037 <= x <= 0.124) solid solutions were synthesized via hydrogen reduction ofLi2MoO4in the temperature range of 650-1100 degrees C, withxdecreasing with theincrease of the reduction temperature. The solid solutions adopt a monoclinicallydistorted O3-type layered average structure and demonstrate a robust localordering of the Li cations and Mo3triangular clusters within the mixed Li/Mocationic layers. The local structure was scrutinized in detail by electron diffractionand aberration-corrected scanning transmission electron microcopy (STEM),resulting in an ordering model comprising a uniform distribution of the Mo3clusters compatible with local electroneutrality and chemical composition. The geometry of the triangular clusters with their oxygenenvironment (Mo3O13groups) has been directly visualized using differential phase contrast STEM imaging. The established localstructure was used as input for density functional theory (DFT)-based calculations; they support the proposed atomic arrangementand provide a plausible explanation for the staircase galvanostatic charge profiles upon electrochemical Li+extraction fromLi2+xMo1-xO3in Li cells. According to DFT, all electrochemical capacity in Li2+xMo1-xO3solely originates from the cationic Moredox process, which proceeds via oxidation of the Mo3triangular clusters into bent Mo3chains where the electronic capacity of the clusters depends on the initial chemical composition and Mo oxidation state defining the width of the first charge low-voltageplateau. Further oxidation at the high-voltage plateau proceeds through decomposition of the Mo3chains into Mo2dimers and further into individual Mo6+cations
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000789034200023 Publication Date 2022-04-01
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0020-1669 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.6 Times cited (down) 3 Open Access Not_Open_Access
Notes The authors acknowledge Russian Science Foundation (grant 20-43-01012) and Research Foundation Flanders (FWO Vlaanderen, project number G0F1320N) for financial support. The authors are grateful to AICF of Skoltech for providing access to electron microscopy equipment. The authors are grateful to Prof. G. Van Tendeloo for discussing the results. Approved Most recent IF: 4.6
Call Number UA @ admin @ c:irua:188631 Serial 7079
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