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Author Jin, L.; Batuk, M.; Kirschner, F.K.K.; Lang, F.; Blundell, S.J.; Hadermann, J.; Hayward, M.A. url  doi
openurl 
  Title Exsolution of SrO during the Topochemical Conversion of LaSr3CoRuO8to the Oxyhydride LaSr3CoRuO4H4 Type A1 Journal article
  Year 2019 Publication Inorganic chemistry Abbreviated Journal Inorg Chem  
  Volume 58 Issue 21 Pages 14863-14870  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Reaction of the n = 1 Ruddlesden-Popper oxide LaSr3CoRuO8 with CaH2 yields the oxyhydride phase LaSr3CoRuO4H4 via topochemical anion-exchange. Close inspection of X-ray and neutron powder diffraction data in combination with HAADF-STEM images reveals that nanoparticles of SrO are exsolved from the system during the reaction, with the change in cation stoichiometry accommodated by the inclusion of n > 1 (Co/Ru)nOn+1H2n ‘perovskite’ layers into the Ruddlesden-Popper stacking sequence. This novel pseudo-topochemical process offers a new route for the formation of n > 1 Ruddlesden-Popper structured materials. Magnetization data are consistent with a LaSr3Co1+Ru2+O4H4 (Co1+, d8, S = 1; Ru2+, d6, S = 0) oxidation/spin state combination. Neutron diffraction and μ+SR data show no evidence for long-range magnetic order down to 2 K, suggesting the diamagnetic Ru2+ centers impede the Co-Co magnetic exchange interactions.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000494894400062 Publication Date 2019-11-04  
  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 (down) 4.857 Times cited 1 Open Access  
  Notes We thank P. Manuel for assistance collecting the neutron powder diffraction data. We thank The Leverhulme Trust grant award RPG-2014-366 “Topochemical reduction of 4d and 5d transition metal oxides” for supporting this work. Experiments at the Diamond Light Source were performed as part of the Block Allocation Group award “Oxford Solid State Chemistry BAG to probe composition-structure-property relationships in solids” (EE13284). Investigation by TEM was supported through the FWO grant G035619N. Approved Most recent IF: 4.857  
  Call Number EMAT @ emat @c:irua:164625 Serial 5434  
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Author Khelifi, S.; Brammertz, G.; Choubrac, L.; Batuk, M.; Yang, S.; Meuris, M.; Barreau, N.; Hadermann, J.; Vrielinck, H.; Poelman, D.; Neyts, K.; Vermang, B.; Lauwaert, J. pdf  url
doi  openurl
  Title The path towards efficient wide band gap thin-film kesterite solar cells with transparent back contact for viable tandem application Type A1 Journal article
  Year 2021 Publication Solar Energy Materials And Solar Cells Abbreviated Journal Sol Energ Mat Sol C  
  Volume 219 Issue Pages 110824  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract Wide band gap thin-film kesterite solar cell based on non-toxic and earth-abundant materials might be a suitable candidate as a top cell for tandem configuration in combination with crystalline silicon as a bottom solar cell. For this purpose and based on parameters we have extracted from electrical and optical characterization techniques of Cu2ZnGeSe4 absorbers and solar cells, a model has been developed to describe the kesterite top cell efficiency limitations and to investigate the different possible configurations with transparent back contact for fourterminal tandem solar cell application. Furthermore, we have studied the tandem solar cell performance in view of the band gap and the transparency of the kesterite top cell and back contact engineering. Our detailed analysis shows that a kesterite top cell with efficiency > 14%, a band gap in the range of 1.5-1.7 eV and transparency above 80% at the sub-band gaps photons energies are required to achieve a tandem cell with higher efficiency than with a single silicon solar cell.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000591683500002 Publication Date 2020-10-08  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0927-0248 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (down) 4.784 Times cited Open Access OpenAccess  
  Notes The authors would like to acknowledge the SWInG project financed by the European Union’s Horizon 2020 research and innovation programme under grant agreement No 640868 and the Research Foundation Flanders-Hercules Foundation (FWO-Vlaanderen, project No AUGE/13/16:FT-IMAGER). Approved Most recent IF: 4.784  
  Call Number EMAT @ emat @c:irua:174337 Serial 6706  
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Author Zhang, F.; Chevalier, J.; Olagnon, C.; Batuk, M.; Hadermann, J.; Van Meerbeek, B.; Vleugels, J. pdf  doi
openurl 
  Title Grain-boundary engineering for aging and slow-crack-growth resistant zirconia Type A1 Journal article
  Year 2017 Publication Journal of dental research Abbreviated Journal J Dent Res  
  Volume 96 Issue 7 Pages 774-779  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Ceramic materials are prone to slow crack growth, resulting in strength degradation over time. Although yttria-stabilized zirconia (Y-TZP) ceramics have higher crack resistance than other dental ceramics, their aging susceptibility threatens their long-term performance in aqueous environments such as the oral cavity. Unfortunately, increasing the aging resistance of Y-TZP ceramics normally reduces their crack resistance. Our recently conducted systematic study of doping 3Y-TZP with various trivalent cations revealed that lanthanum oxide (La2O3) and aluminum oxide (Al2O3) have the most potent effect to retard the aging kinetics of 3Y-TZP. In this study, the crack-propagation behavior of La2O3 and Al2O3 co-doped 3Y-TZP ceramics was investigated by double-torsion methods. The grain boundaries were examined using scanning transmission electron microscopy and energy-dispersive spectroscopy (STEM-EDS). Correlating these analytic data with hydrothermal aging studies using different doping systems, a strategy to strongly bind the segregated dopant cations with the oxygen vacancies at the zirconia-grain boundary was found to improve effectively the aging resistance of Y-TZP ceramics without affecting the resistance to crack propagation.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication St. Louis, Mo. Editor  
  Language Wos 000403934500010 Publication Date 2017-03-10  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0022-0345 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (down) 4.755 Times cited 3 Open Access Not_Open_Access  
  Notes ; This research was supported by the Research Fund of KU Leuven under project 0T/ 10/052 and the Research Foundation-Flanders (FWO-Vlaanderen) under grant G.0431.10N. We thank J.W. Seo for TEM and sample preparations. F. Zhang thanks the Research Fund of KU Leuven for her postdoctoral fellowship (PDM/15/153) and the JECS-Trust for the travel grant (No. 201599) to perform double-torsion testing in the MATEIS lab of INSA, Lyon, France. Jerome Chevalier would like to dedicate this paper to Maria Cattani Lorente, who recently passed away under tragic conditions. She was deeply involved in the study of dental zirconia and we will miss her. The authors declare no potential conflicts of interest with respect to the authorship and/or publication of this article. ; Approved Most recent IF: 4.755  
  Call Number UA @ lucian @ c:irua:144161 Serial 4660  
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Author Xu, X.; Jones, M.A.; Cassidy, S.J.; Manuel, P.; Orlandi, F.; Batuk, M.; Hadermann, J.; Clarke, S.J. pdf  url
doi  openurl
  Title Magnetic Ordering in the Layered Cr(II) Oxide Arsenides Sr2CrO2Cr2As2and Ba2CrO2Cr2As2 Type A1 Journal article
  Year 2020 Publication Inorganic Chemistry Abbreviated Journal Inorg Chem  
  Volume 59 Issue 21 Pages 15898-15912  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Sr2CrO2Cr2As2 and Ba2CrO2Cr2As2 with Cr2+ ions in CrO2 sheets and in CrAs layers crystallize with the Sr2Mn3Sb2O2 structure (space group I4/mmm, Z = 2) and lattice parameters a = 4.00800(2) Å, c = 18.8214(1) Å (Sr2CrO2Cr2As2) and a = 4.05506(2) Å, c = 20.5637(1) Å (Ba2CrO2Cr2As2) at room temperature. Powder neutron diffraction reveals checkerboard-type antiferromagnetic ordering of the Cr2+ ions in the arsenide layers below TN1Sr, of 600(10) K (Sr2CrO2Cr2As2) and TN1Ba 465(5) K (Ba2CrO2Cr2As2) with the moments initially directed perpendicular to the layers in both compounds. Checkerboard-type antiferromagnetic ordering of the Cr2+ ions in the oxide layer below 230(5) K for Ba2CrO2Cr2As2 occurs with these moments also perpendicular to the layers, consistent with the orientation preferences of d4 moments in the two layers. In contrast, below 330(5) K in Sr2CrO2Cr2As2, the oxide layer Cr2+ moments are initially oriented in the CrO2 plane; but on further cooling, these moments rotate to become perpendicular to the CrO2 planes, while the moments in the arsenide layers rotate by 90° with the moments on the two sublattices remaining orthogonal throughout [behavior recently reported independently by Liu et al. [Liu et al. Phys. Rev. B 2018, 98, 134416]]. In Sr2CrO2Cr2As2, electron diffraction and high resolution powder X-ray diffraction data show no evidence for a structural distortion that would allow the two Cr2+ sublattices to couple, but high resolution neutron powder diffraction data suggest a small incommensurability between the magnetic structure and the crystal structure, which may account for the coupling of the two sublattices and the observed spin reorientation. The saturation values of the Cr2+ moments in the CrO2 layers (3.34(1) μB (for Sr2CrO2Cr2As2) and 3.30(1) μB (for Ba2CrO2Cr2As2)) are larger than those in the CrAs layers (2.68(1) μB for Sr2CrO2Cr2As2 and 2.298(8) μB for Ba2CrO2Cr2As2) reflecting greater covalency in the arsenide layers.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000588738100035 Publication Date 2020-11-02  
  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 (down) 4.6 Times cited Open Access OpenAccess  
  Notes We thank the UK EPSRC (EP/M020517/1 and EP/P018874/ 1) and the Leverhulme Trust (RPG-2014-221) for funding and the ISIS pulsed neutron and muon source (RB1610357 and RB1700075) and the Diamond Light Source Ltd. (EE13284 and EE18786) for the award of beam time. We thank Dr. A. Baker and Dr. C. Murray for support on I11. Approved Most recent IF: 4.6; 2020 IF: 4.857  
  Call Number EMAT @ emat @c:irua:176058 Serial 6704  
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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. pdf  doi
openurl 
  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 (down) 4.6 Times cited 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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Author Sheath, B.C.; Xu, X.; Manuel, P.; Hadermann, J.; Batuk, M.; O'Sullivan, J.; Bonilla, R.S.; Clarke, S.J. url  doi
openurl 
  Title Structures and magnetic ordering in layered Cr oxide arsenides Sr₂CrO₂Cr₂OAs₂ and Sr₂CrO₃CrAs Type A1 Journal article
  Year 2022 Publication Inorganic chemistry Abbreviated Journal Inorg Chem  
  Volume 61 Issue 31 Pages 10-12385  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Two novel chromium oxide arsenide materials have been synthesized, Sr2CrO2Cr2OAs2 (i.e., Sr2Cr3As2O3) and Sr2CrO3CrAs (i.e., Sr2Cr2AsO3), both of which contain chromium ions in two distinct layers. Sr2CrO2Cr2OAs2 was targeted following electron microscopy measurements on a related phase. It crystallizes in the space group P4/mmm and accommodates distorted CrO4As2 octahedra containing Cr2+ and distorted CrO(2)As(4 )octahedra containing Cr3+. In contrast, Sr2CrO3CrAs incorporates Cr3+ in CrO5 square-pyramidal coordination in [Sr2CrO3](+) layers and Cr2+ ions in CrAs(4 )tetrahedra in [CrAs](-) layers and crystallizes in the space group P4/nmm. Powder neutron diffraction data reveal antiferromagnetic ordering in both compounds. In Sr2CrO3CrAs the Cr2+ moments in the [CrAs](-) layers exhibit long-range ordering, while the Cr3+ moments in the [Sr2CrO3](+) layers only exhibit short-range ordering. However, in Sr2CrO2Cr2OAs2, both the Cr(2+ )moments in the CrO4As2 environments and the Cr3+ moments in the CrO2As4 polyhedra are long-range-ordered below 530(10) K. Above this temperature, only the Cr3+ moments are ordered with a Neel temperature slightly in excess of 600 K. A subtle structural change is evident in Sr2CrO2Cr2OAs2 below the magnetic ordering transitions.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000841943600001 Publication Date 2022-07-27  
  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 (down) 4.6 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 4.6  
  Call Number UA @ admin @ c:irua:190007 Serial 7215  
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Author Gamon, J.; Bassat, J.-M.; Villesuzanne, A.; Duttine, M.; Batuk, M.; Vandemeulebroucke, D.; Hadermann, J.; Alassani, F.; Weill, F.; Durand, E.; Demourgues, A. pdf  doi
openurl 
  Title Impact of anionic ordering on the iron site distribution and valence states in oxyfluoride Sr2FeO3+xF1-x(x=0.08, 0.2) with a layered Perovskite network Type A1 Journal article
  Year 2023 Publication Inorganic chemistry Abbreviated Journal  
  Volume 62 Issue 27 Pages 10822-10832  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Sr2FeO3+x F1-x (x = 0.08, 0.2), an n = 1 Ruddlesden-Popperphase, was synthesized from the oxidationof Sr2FeO3F in air at high temperature followinga fluorine for oxygen substitution and Fe3+ to Fe4+ oxidation. A structural investigation of both compounds was performedusing complementary and high-resolution techniques (Synchrotron X-rayand electron diffraction, Mo''ssbauer spectroscopy, HR-STEM)coupled to DFT calculation. This study reveals that oxidation leadsto a high degree of apical anion disorder coupled to antiphase boundaries. Sr2FeO3F, an oxyfluoride compoundwith an n = 1 Ruddlesden-Popper structure,was identifiedas a potential interesting mixed ionic and electronic conductor (MIEC).The phase can be synthesized under a range of different pO(2) atmospheres, leading to various degrees of fluorinefor oxygen substitution and Fe4+ content. A structuralinvestigation and thorough comparison of both argon- and air-synthesizedcompounds were performed by combining high-resolution X-ray and electrondiffraction, high-resolution scanning transmission electron microscopy,Mo''ssbauer spectroscopy, and DFT calculations. While the argon-synthesizedphase shows a well-behaved O/F ordered structure, this study revealedthat oxidation leads to averaged large-scale anionic disorder on theapical site. In the more oxidized Sr2FeO3.2F0.8 oxyfluoride, containing 20% of Fe4+, two differentFe positions can be identified with a 32%/68% occupancy (P4/nmm space group). This originates due to the presenceof antiphase boundaries between ordered domains within the grains.Relations between site distortion and valence states as well as stabilityof apical anionic sites (O vs F) are discussed. This study paves theway for further studies on both ionic and electronic transport propertiesof Sr2FeO3.2F0.8 and its use in MIEC-baseddevices, such as solid oxide fuel cells.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 001018974700001 Publication Date 2023-06-29  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0020-1669 ISBN Additional Links UA library record; WoS full record  
  Impact Factor (down) 4.6 Times cited Open Access Not_Open_Access  
  Notes Approved Most recent IF: 4.6; 2023 IF: 4.857  
  Call Number UA @ admin @ c:irua:197789 Serial 8881  
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Author Buffière, M.; Zaghi, A.E.; Lenaers, N.; Batuk, M.; Khelifi, S.; Drijkoningen, J.; Hamon, J.; Stesmans, A.; Kepa, J.; Afanas’ev, V.V.; Hadermann, J.; D’Haen, J.; Manca, J.; Vleugels, J.; Meuris, M.; Poortmans, J.; pdf  url
doi  openurl
  Title Effect of binder content in Cu-In-Se precursor ink on the physical and electrical properties of printed CuInSe2 solar cells Type A1 Journal article
  Year 2014 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C  
  Volume 118 Issue 47 Pages 27201-27209  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract Printed chalcopyrite thin films have attracted considerable attention in recent years due to their potential in the high-throughput production of photovoltaic devices. To improve the homogeneity of printed CuInSe2 (CISe) layers, chemical additives such as binder can be added to the precursor ink. In this contribution, we investigate the influence of the dicyandiamide (DCDA) content, used as a binder in the precursor ink, on the physical and electrical properties of printed CISe solar cells. It is shown that the use of the binder leads to a dense absorber, composed of large CISe grains close to the surface, while the bulk of the layer consists of CISe crystallites embedded in a CuxS particle based matrix, resulting from the limited sintering of the precursor in this region. The expected additional carbon contamination of the CISe layer due to the addition of the binder appears to be limited, and the optical properties of the CISe layer are similar to the reference sample without additive. The electrical characterization of the corresponding CISe/CdS solar cells shows a degradation of the efficiency of the devices, due to a modification in the predominant recombination mechanisms and a limitation of the space charge region width when using the binder; both effects could be explained by the inhomogeneity of the bulk of the CISe absorber and high defect density at the CISe/CuxS-based matrix interface.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Washington, D.C. Editor  
  Language Wos 000345722400003 Publication Date 2014-11-06  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1932-7447;1932-7455; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (down) 4.536 Times cited 4 Open Access  
  Notes Approved Most recent IF: 4.536; 2014 IF: 4.772  
  Call Number UA @ lucian @ c:irua:121332 Serial 801  
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Author Zhang, F.; Inokoshi, M.; Batuk, M.; Hadermann, J.; Naert, I.; Van Meerbeek, B.; Vleugels, J. pdf  doi
openurl 
  Title Strength, toughness and aging stability of highly-translucent Y-TZP ceramics for dental restorations Type A1 Journal article
  Year 2016 Publication Dental Materials Abbreviated Journal Dent Mater  
  Volume 32 Issue 32 Pages e327-e337  
  Keywords A1 Journal article; Electron Microscopy for Materials Science (EMAT);  
  Abstract OBJECTIVE: The aim was to evaluate the optical properties, mechanical properties and aging stability of yttria-stabilized zirconia with different compositions, highlighting the influence of the alumina addition, Y2O3 content and La2O3 doping on the translucency. METHODS: Five different Y-TZP zirconia powders (3 commercially available and 2 experimentally modified) were sintered under the same conditions and characterized by X-ray diffraction with Rietveld analysis and scanning electron microscopy (SEM). Translucency (n=6/group) was measured with a color meter, allowing to calculate the translucency parameter (TP) and the contrast ratio (CR). Mechanical properties were appraised with four-point bending strength (n=10), single edge V-notched beam (SEVNB) fracture toughness (n=8) and Vickers hardness (n=10). The aging stability was evaluated by measuring the tetragonal to monoclinic transformation (n=3) after accelerated hydrothermal aging in steam at 134 degrees C, and the transformation curves were fitted by the Mehl-Avrami-Johnson (MAJ) equation. Data were analyzed by one-way ANOVA, followed by Tukey's HSD test (alpha=0.05). RESULTS: Lowering the alumina content below 0.25wt.% avoided the formation of alumina particles and therefore increased the translucency of 3Y-TZP ceramics, but the hydrothermal aging stability was reduced. A higher yttria content (5mol%) introduced about 50% cubic zirconia phase and gave rise to the most translucent and aging-resistant Y-TZP ceramics, but the fracture toughness and strength were considerably sacrificed. 0.2mol% La2O3 doping of 3Y-TZP tailored the grain boundary chemistry and significantly improved the aging resistance and translucency. Although the translucency improvement by La2O3 doping was less effective than for introducing a substantial amount of cubic zirconia, this strategy was able to maintain the mechanical properties of typical 3Y-TZP ceramics. SIGNIFICANCE: Three different approaches were compared to improve the translucency of 3Y-TZP ceramics.  
  Address KU Leuven, Department of Materials Engineering, Kasteelpark Arenberg 44, Belgium  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Wos 000389516400003 Publication Date 2016-10-06  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0109-5641 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (down) 4.07 Times cited Open Access  
  Notes The authors acknowledge the Research Fund of KU Leu- ven under project 0T/10/052 and the Fund for Scientific Research Flanders (FWO-Vlaanderen) under grant G.0431.10N. F. Zhang thanks the Research Fund of KU Leuven for her post- doctoral fellowship (PDM/15/153). We thank M. Peumans for the translucency measurements. Approved Most recent IF: 4.07  
  Call Number EMAT @ emat @ c:irua:136821 Serial 4313  
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Author Zhang, F.; Inokoshi, M.; Batuk, M.; Hadermann, J.; Naert, I.; Van Meerbeek, B.; Vleugels, J. pdf  doi
openurl 
  Title Strength, toughness and aging stability of highly-translucent Y-TZP ceramics for dental restorations Type A1 Journal article
  Year 2016 Publication Dental materials Abbreviated Journal Dent Mater  
  Volume 32 Issue 12 Pages E327-E337  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Objective. The aim was to evaluate the optical properties, mechanical properties and aging stability of yttria-stabilized zirconia with different compositions, highlighting the influence of the alumina addition, Y2O3 content and La2O3 doping on the translucency. Methods. Five different Y-TZP zirconia powders (3 commercially available and 2 experimentally modified) were sintered under the same conditions and characterized by X-ray diffraction with Rietveld analysis and scanning electron microscopy (SEM). Translucency (n = 6/group) was measured with a color meter, allowing to calculate the translucency parameter (TP) and the contrast ratio (CR). Mechanical properties were appraised with four-point bending strength (n = 10), single edge V-notched beam (SEVNB) fracture toughness (n = 8) and Vickers hardness (n = 10). The aging stability was evaluated by measuring the tetragonal to monoclinic transformation (n = 3) after accelerated hydrothermal aging in steam at 134 degrees C, and the transformation curves were fitted by the Mehl-Avrami-Johnson (MAJ) equation. Data were analyzed by one-way ANOVA, followed by Tukey's HSD test (alpha = 0.05). Results. Lowering the alumina content below 0.25 wt.% avoided the formation of alumina particles and therefore increased the translucency of 3Y-TZP ceramics, but the hydrothermal aging stability was reduced. A higher yttria content (5 mol%) introduced about 50% cubic zirconia phase and gave rise to the most translucent and aging-resistant Y-TZP ceramics, but the fracture toughness and strength were considerably sacrificed. 0.2 mol% La2O3 doping of 3Y-TZP tailored the grain boundary chemistry and significantly improved the aging resistance and translucency. Although the translucency improvement by La2O3 doping was less effective than for introducing a substantial amount of cubic zirconia, this strategy was able to maintain the mechanical properties of typical 3Y-TZP ceramics. Significance. Three different approaches were compared to improve the translucency of 3YTZP ceramics. (C) 2016 The Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Copenhagen Editor  
  Language Wos 000389516400003 Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0109-5641 ISBN Additional Links UA library record; WoS full record  
  Impact Factor (down) 4.07 Times cited 47 Open Access  
  Notes Approved Most recent IF: 4.07  
  Call Number UA @ lucian @ c:irua:140246 Serial 4447  
Permanent link to this record
 

 
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 1477-9226;1477-9234; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (down) 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 Charkin, D.O.; Akinfiev, V.S.; Alekseeva, A.M.; Batuk, M.; Abakumov, A.M.; Kazakov, S.M. doi  openurl
  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 (down) 4.029 Times cited 5 Open Access  
  Notes Approved Most recent IF: NA  
  Call Number UA @ lucian @ c:irua:130330 Serial 4256  
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Author Mallick, S.; Zhang, W.; Batuk, M.; Gibbs, A.S.; Hadermann, J.; Halasyamani, P.S.; Hayward, M.A. url  doi
openurl 
  Title The crystal and defect structures of polar KBiNb2O7 Type A1 Journal article
  Year 2022 Publication Journal of the Chemical Society : Dalton transactions Abbreviated Journal Dalton T  
  Volume 51 Issue 5 Pages 1866-1873  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract KBiNb2O7 was prepared from RbBiNb2O7 by a sequence of cation exchange reactions which first convert RbBiNb2O7 to LiBiNb2O7, before KBiNb2O7 is formed by a further K-for-Li cation exchange. A combination of neutron, synchrotron X-ray and electron diffraction data reveal that KBiNb2O7 adopts a polar, layered, perovskite structure (space group A11m) in which the BiNb2O7 layers are stacked in a (0, ½, z) arrangement, with the K+ cations located in half of the available 10-coordinate interlayer cation sites. The inversion symmetry of the phase is broken by a large displacement of the Bi3+ cations parallel to the y-axis. HAADF-STEM images reveal that KBiNb2O7 exhibits frequent stacking faults which convert the (0. ½, z) layer stacking to (½, 0, z) stacking and vice versa, essentially switching the x- and y-axes of the material. By fitting the complex diffraction peak shape of the SXRD data collected from KBiNb2O7 it is estimated that each layer has approximately an ~11% chance of being defective – a high level which is attributed to the lack of cooperative NbO6 tilting in the material, which limits the lattice strain associated with each fault.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000741540300001 Publication Date 2022-01-05  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1477-9226 ISBN Additional Links UA library record; WoS full record  
  Impact Factor (down) 4 Times cited Open Access OpenAccess  
  Notes Experiments at the Diamond Light Source were performed as part of the Block Allocation Group award “Oxford/Warwick Solid State Chemistry BAG to probe composition-structure-property relationships in solids” (EE18786). Experiments at the ISIS pulsed neutron facility were supported by a beam time allocation from the STFC (RB 2000148). SM thanks Somerville College for an Oxford Ryniker Lloyd scholarship. PSH and WZ thank the National Science Foundation (DMR-2002319) for support. Approved Most recent IF: 4  
  Call Number EMAT @ emat @c:irua:185504 Serial 6951  
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Author Ulu Okudur, F.; Batuk, M.; Hadermann, J.; Safari, M.; De Sloovere, D.; Kumar Mylavarapu, S.; Joos, B.; D'Haen, J.; Van Bael, M.K.; Hardy, A. url  doi
openurl 
  Title Solution-gel-based surface modification of LiNi0.5Mn1.5O4-δ with amorphous Li-Ti-O coating Type A1 Journal article
  Year 2023 Publication RSC advances Abbreviated Journal  
  Volume 13 Issue 47 Pages 33146-33158  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract LNMO (LiNi0.5Mn1.5O4-delta) is a high-energy density positive electrode material for lithium ion batteries. Unfortunately, it suffers from capacity loss and impedance rise during cycling due to electrolyte oxidation and electrode/electrolyte interface instabilities at high operating voltages. Here, a solution-gel synthesis route was used to coat 0.5-2.5 mu m LNMO particles with amorphous Li-Ti-O (LTO) for improved Li conduction, surface structural stability and cyclability. High-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) analysis coupled with energy dispersive X-ray (EDX) showed Ti-rich amorphous coatings/islands or Ti-rich spinel layers on many of the LTO-modified LNMO facets, with a thickness varying from about 1 to 10 nm. The surface modification in the form of amorphous islands was mostly possible on high-energy crystal facets. Physicochemical observations were used to propose a molecular mechanism for the surface modification, combining insights from metalorganic chemistry with the crystallographic properties of LNMO. The improvements in functional properties were investigated in half cells. The cell impedance increased faster for the bare LNMO compared to amorphous LTO modified LNMO, resulting in R-ct values as high as 1247 Omega (after 1000 cycles) for bare LNMO, against 216 Omega for the modified material. At 10C, the modified material boosted a 15% increase in average discharge capacity. The improvements in electrochemical performance were attributed to the increase in electrochemically active surface area, as well as to improved HF-scavenging, resulting in the formation of protective byproducts, generating a more stable interface during prolonged cycling.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 001102666700001 Publication Date 2023-11-09  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2046-2069 ISBN Additional Links UA library record; WoS full record  
  Impact Factor (down) 3.9 Times cited Open Access  
  Notes Approved Most recent IF: 3.9; 2023 IF: 3.108  
  Call Number UA @ admin @ c:irua:202091 Serial 9096  
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Author Juchtmans, R.; Béché, A.; Abakumov, A.; Batuk, M.; Verbeeck, J. url  doi
openurl 
  Title Using electron vortex beams to determine chirality of crystals in transmission electron microscopy Type A1 Journal article
  Year 2015 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 91 Issue 91 Pages 094112  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract We investigate electron vortex beams elastically scattered on chiral crystals. After deriving a general expression for the scattering amplitude of a vortex electron, we study its diffraction on point scatterers arranged on a helix. We derive a relation between the handedness of the helix and the topological charge of the electron vortex on one hand and the symmetry of the higher-order Laue zones in the diffraction pattern on the other for kinematically and dynamically scattered electrons. We then extend this to atoms arranged on a helix as found in crystals which belong to chiral space groups and propose a method to determine the handedness of such crystals by looking at the symmetry of the diffraction pattern. In contrast to alternative methods, our technique does not require multiple scattering, which makes it possible to also investigate extremely thin samples in which multiple scattering is suppressed. In order to verify the model, elastic scattering simulations are performed, and an experimental demonstration on Mn2Sb2O7 is given in which we find the sample to belong to the right-handed variant of its enantiomorphic pair. This demonstrates the usefulness of electron vortex beams to reveal the chirality of crystals in a transmission electron microscope and provides the required theoretical basis for further developments in this field.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000352017000002 Publication Date 2015-03-27  
  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 (down) 3.836 Times cited 54 Open Access  
  Notes Fwo; 312483 Esteem2; 278510 Vortex; esteem2jra1; esteem2jra2 ECASJO_; Approved Most recent IF: 3.836; 2015 IF: 3.736  
  Call Number c:irua:125512 c:irua:125512 Serial 3825  
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Author Ranjbar, S.; Hadipour, A.; Vermang, B.; Batuk, M.; Hadermann, J.; Garud, S.; Sahayaraj, S.; Meuris, M.; Brammertz, G.; da Cunha, A.F.; Poortmans, J. pdf  url
doi  openurl
  Title P-N Junction Passivation in Kesterite Solar Cells by Use of Solution-Processed TiO2 Layer Type A1 Journal article
  Year 2017 Publication IEEE journal of photovoltaics Abbreviated Journal Ieee J Photovolt  
  Volume 7 Issue 7 Pages 1130-1135  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract In this work, we used a solution-processed TiO2 layer between Cu2ZnSnSe4 and CdS buffer layer to reduce the recombination at the p–n junction. Introducing the TiO2 layer showed a positive impact on VOC but fill factor and efficiency decreased. Using a KCN treatment, we could create openings in the TiO2 layer, as confirmed by transmission electron microscopy measurements. Formation of these openings in the TiO2 layer led to the improvement of the short-circuit current, fill factor, and the efficiency of the modified solar cells.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000404258900026 Publication Date 2017-04-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2156-3381 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (down) 3.712 Times cited 2 Open Access OpenAccess  
  Notes This work was supported in part by the European Union’s Horizon 2020 research and innovation program under Grant 640868, in part by the Flemish government, Department Economy, Science and Innovation, in part by the FEDER funds through the COMPETE 2020 Programme, and in part by the National Funds through FCT – Portuguese Foundation for Science and Technology under the project UID/CTM/50025/2013. The work of S. Ranjbar was supported by the Portuguese Science and Technology Foundation through Ph.D. grant SFRH/BD/78409/2011. The work of B. Vermang was supported by the Flemish Research Foundation FWO (mandate 12O4215N). Approved Most recent IF: 3.712  
  Call Number EMAT @ emat @ c:irua:143986 Serial 4583  
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Author Kutukov, P.; Rumyantseva, M.; Krivetskiy, V.; Filatova, D.; Batuk, M.; Hadermann, J.; Khmelevsky, N.; Aksenenko, A.; Gaskov, A. url  doi
openurl 
  Title Influence of Mono- and Bimetallic PtOx, PdOx, PtPdOx Clusters on CO Sensing by SnO2 Based Gas Sensors Type A1 Journal Article
  Year 2018 Publication Nanomaterials Abbreviated Journal Nanomaterials-Basel  
  Volume 8 Issue 11 Pages 917  
  Keywords A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ;  
  Abstract To obtain a nanocrystalline SnO2 matrix and mono- and bimetallic nanocomposites SnO2/Pd, SnO2/Pt, and SnO2/PtPd, a flame spray pyrolysis with subsequent impregnation was used. The materials were characterized using X-ray diffraction (XRD), a single-point BET method, transmission electron microscopy (TEM), and high angle annular dark field scanning transmission electron microscopy (HAADF-STEM) with energy dispersive X-ray (EDX) mapping. The electronic state of the metals in mono- and bimetallic clusters was determined using X-ray photoelectron spectroscopy (XPS). The active surface sites were investigated using the Fourier Transform infrared spectroscopy (FTIR) and thermo-programmed reduction with hydrogen (TPR-H-2) methods. The sensor response of blank SnO2 and nanocomposites had a carbon monoxide (CO) level of 6.7 ppm and was determined in the temperature range 60-300 degrees C in dry (Relative Humidity (RH) = 0%) and humid (RH = 20%) air. The sensor properties of the mono- and bimetallic nanocomposites were analyzed on the basis of information on the electronic state, the distribution of modifiers in SnO2 matrix, and active surface centers. For SnO2/PtPd, the combined effect of the modifiers on the electrophysical properties of SnO2 explained the inversion of sensor response from n- to p-types observed in dry conditions.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000451316100052 Publication Date 2018-11-07  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2079-4991 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (down) 3.553 Times cited 7 Open Access Not_Open_Access  
  Notes This research was funded by the Russian Ministry of Education and Sciences (Agreement No. 14.613.21.0075, RFMEFI61317X0075). Approved Most recent IF: 3.553  
  Call Number EMAT @ emat @c:irua:155767 Serial 5139  
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Author Zhang, F.; Vanmeensel, K.; Inokoshi, M.; Batuk, M.; Hadermann, J.; Van Meerbeek, B.; Naert, I.; Vleugels, J. doi  openurl
  Title 3Y-TZP ceramics with improved hydrothermal degradation resistance and fracture toughness Type A1 Journal article
  Year 2014 Publication Journal of the European Ceramic Society Abbreviated Journal J Eur Ceram Soc  
  Volume 34 Issue 10 Pages 2453-2463  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Different factors such as the way of incorporating the Y2O3 stabilizer, alumina addition and sintering temperature were assessed with the goal to improve the low temperature degradation (LTD) resistance of 3Y-TZP without compromising on the mechanical properties. The degradation of hydrothermally treated specimens was studied by X-ray diffraction, micro-Raman spectroscopy and scanning electron microscopy. Decreasing the sintering temperature decreased the LTD susceptibility of 3Y-TZPs but did not allow to obtain a LTD resistant 3Y-TZP with optimized mechanical properties. Alumina addition along with the use of Y2O3 stabilizer coated starting powder allowed to combine both an excellent toughness and LTD resistance, as compared to alumina-free and stabilizer co-precipitated powder based equivalents. Transmission electron microscopy revealed that the improved LTD resistance could be attributed to the segregation of Al3+ at the grain boundary and the heterogeneously distributed Y3+ stabilizer.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Barking Editor  
  Language Wos 000336352500033 Publication Date 2014-03-07  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0955-2219; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (down) 3.411 Times cited 48 Open Access  
  Notes Fwo G.0431.10n Approved Most recent IF: 3.411; 2014 IF: 2.947  
  Call Number UA @ lucian @ c:irua:117065 c:irua:117065 Serial 11  
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Author Zhang, F.; Vanmeensel, K.; Inokoshi, M.; Batuk, M.; Hadermann, J.; Van Meerbeek, B.; Naert, I.; Vleugels, J. pdf  doi
openurl 
  Title Critical influence of alumina content on the low temperature degradation of 2-3 mol% yttria-stabilized TZP for dental restorations Type A1 Journal article
  Year 2015 Publication Journal of the European Ceramic Society Abbreviated Journal J Eur Ceram Soc  
  Volume 35 Issue 35 Pages 741-750  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract The influence of 0.25, 2 and 5 wt.% alumina addition on the mechanical properties and low temperature degradation (LTD) of 3, 2.5 and 2 mol% yttria-stabilized TZP ceramics was investigated. The amount of alumina addition was observed to have a crucial impact on the degradation of Y-TZP ceramics. Independent on the yttria stabilizer content, 0.25 wt.% alumina had a higher degradation retarding effect to Y-TZP ceramics than 2 and 5 wt.% of alumina addition, which had a comparable effect. The apparent activation energy for the degradation process was increased by adding alumina, but it was the same for 0.255 wt.% alumina doped 3Y-TZP ceramics. For Y-TZPs containing a small amount of alumina addition, only the segregated Al3+ at the grain boundaries of the zirconia grains was effective to retard the degradation of Y-TZPs. The secondary phase Al2O3 grains increased the degradation kinetics, which might be attributed to the residual stresses.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Barking Editor  
  Language Wos 000345201700032 Publication Date 2014-09-27  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0955-2219; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (down) 3.411 Times cited 37 Open Access  
  Notes Fwo G043110n Approved Most recent IF: 3.411; 2015 IF: 2.947  
  Call Number c:irua:121328 Serial 544  
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Author Buffière, M.; Brammertz, G.; Batuk, M.; Verbist, C.; Mangin, D.; Koble, C.; Hadermann, J.; Meuris, M.; Poortmans, J. pdf  url
doi  openurl
  Title Microstructural analysis of 9.7% efficient Cu2ZnSnSe4 thin film solar cells Type A1 Journal article
  Year 2014 Publication Applied physics letters Abbreviated Journal Appl Phys Lett  
  Volume 105 Issue 18 Pages 183903  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract This work presents a detailed analysis of the microstructure and the composition of our record Cu 2ZnSnSe4 (CZTSe)-CdS-ZnO solar cell with a total area efficiency of 9.7%. The average composition of the CZTSe crystallites is Cu 1.94 Zn 1.12Sn0.95Se3.99. Large crystals of ZnSe secondary phase (up to 400 nm diameter) are observed at the voids between the absorber and the back contact, while smaller ZnSe domains are segregated at the grain boundaries and close to the surface of the CZTSe grains. An underlying layer and some particles of Cu xSe are observed at the Mo-MoSe2-Cu2ZnSnSe4 interface. The free surface of the voids at the back interface is covered by an amorphous layer containing Cu, S, O, and C, while the presence of Cd, Na, and K is also observed in this region.  
  Address  
  Corporate Author Thesis  
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor  
  Language Wos 000345000000086 Publication Date 2014-11-08  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0003-6951;1077-3118; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (down) 3.411 Times cited 17 Open Access  
  Notes Approved Most recent IF: 3.411; 2014 IF: 3.302  
  Call Number UA @ lucian @ c:irua:121329 Serial 2038  
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Author Turner, S.; Egoavil, R.; Batuk, M.; Abakumov, A.A.; Hadermann, J.; Verbeeck, J.; Van Tendeloo, G. pdf  doi
openurl 
  Title Site-specific mapping of transition metal oxygen coordination in complex oxides Type A1 Journal article
  Year 2012 Publication Applied physics letters Abbreviated Journal Appl Phys Lett  
  Volume 101 Issue 24 Pages 241910  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract We demonstrate site-specific mapping of the oxygen coordination number for transition metals in complex oxides using atomically resolved electron energy-loss spectroscopy in an aberration-corrected scanning transmission electron microscope. Pb2Sr2Bi2Fe6O16 contains iron with a constant Fe3+ valency in both octahedral and tetragonal pyramidal coordination and is selected to demonstrate the principle of site-specific coordination mapping. Analysis of the site-specific Fe-L2,3 data reveals distinct variations in the fine structure that are attributed to Fe in a six-fold (octahedron) or five-fold (distorted tetragonal pyramid) oxygen coordination. Using these variations, atomic resolution coordination maps are generated that are in excellent agreement with simulations.  
  Address  
  Corporate Author Thesis  
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor  
  Language Wos 000312490000035 Publication Date 2012-12-12  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0003-6951; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (down) 3.411 Times cited 12 Open Access  
  Notes Fwo; Countatoms; Vortex; Esteem 312483; esteem2jra3 ECASJO; Approved Most recent IF: 3.411; 2012 IF: 3.794  
  Call Number UA @ lucian @ c:irua:105302UA @ admin @ c:irua:105302 Serial 3030  
Permanent link to this record
 

 
Author Bez, R.; Zehani, K.; Batuk, M.; Van Tendeloo, G.; Mliki, N.; Bessais, L. doi  openurl
  Title Structure and magnetic properties of Sm(Fe,Si)(9)C/alpha-Fe nanocomposite magnets Type A1 Journal article
  Year 2017 Publication Journal of alloys and compounds Abbreviated Journal J Alloy Compd  
  Volume 695 Issue 695 Pages 810-817  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract SmFe8.75 Si-0.25 C/alpha-Fe nanocomposites have been successfully synthesized using high energy milling, followed by annealing at 750 degrees C. The crystal structure of these compounds was characterized by the Rietveld method using powder X-ray diffraction data. By increasing the concentration of Sm, we observed a decrease in the amount of alpha-Fe phase. The morphology of the samples was determined by scanning and transmission electron microscopy. The average grain size is about 20 nm. The magnetic properties were investigated at room temperature and at 10 K. A ferromagnetic behavior was observed in all samples at both temperatures. An increase of the soft magnetic phase alpha-Fe induced an increase in the magnetization and a decrease in coercivity. (C) 2016 Elsevier B.V. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Amsterdam Editor  
  Language Wos 000391817600098 Publication Date 2016-10-19  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0925-8388 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (down) 3.133 Times cited 1 Open Access Not_Open_Access  
  Notes ; This work is main supported by the CNRS and the “Ministere de l'Enseignement Superieur, de la Recherche Scientifique” (LR99ES17) (Tunisia), PHC-Utique (Project 11/G 1301) and PHC-Maghreb (Project 15MAG07). The authors acknowledge the French SIE doctoral school of the University Paris Est for its support. ; Approved Most recent IF: 3.133  
  Call Number UA @ lucian @ c:irua:140380 Serial 4448  
Permanent link to this record
 

 
Author Batuk, D.; Batuk, M.; Morozov, V.A.; Meert, K.W.; Smet, P.F.; Poelman, D.; Abakumov, A.M.; Hadermann, J. pdf  url
doi  openurl
  Title Effect of cation vacancies on the crystal structure and luminescent properties of Ca(0.85-1.5x)Gd(x)Eu(0.1)_(0.05+0.5x)WO(4) (0<x<0.567) scheelite-based red phosphors Type A1 Journal article
  Year 2017 Publication Journal of alloys and compounds Abbreviated Journal J Alloy Compd  
  Volume 706 Issue 706 Pages 358-369  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract The Ca0.85-1.5xGdxEu0.1_0.05-0.5xWO4 (0 < x < 0.567) series of cation-deficient scheelites is investigated to unveil the influence of the cation vacancies on the crystal structure and luminescent properties. The concentration of the vacancies is varied by the heterovalent substitution of Gd3+ for Ca2+, keeping the concentration of the Eu3+ luminescent centers constant in all compounds of the series. The crystal structure of the materials is studied using a combination of transmission electron microscopy and synchrotron X-ray powder diffraction. At low vacancy concentration (x = 0.1, 0.2), cations and cation vacancies are randomly distributed in the structure, and the materials preserve the I41/a symmetry of the parent scheelite structure [x = 0.1: a = 5.25151(1) Å, c = 11.39479(2) Å; x = 0.2: a = 5.25042(1) Å, c = 11.41335(2) Å]. At higher concentration, the cation-vacancy ordering gives rise to incommensurately modulated structures. The x = 0.3 structure has a (3 + 2)D tetragonal symmetry [superspace group I41/a(a,b,0)00(-b,a,0)00, a = 5.24700(1) Å, c = 11.45514(3) Å, q1 = 0.51637(14)a* + 0.80761(13)b*, q2 = -0.80761a* + 0.51637b*]. At x = 0.4, the scheelite basic cell undergoes a monoclinic distortion with the formation of the (3 + 1)D structure [superspace group I2/b(a,b,0)00, a = 5.23757(1) Å, b = 5.25035(1) Å, c = 11.45750(2) Å, g = 90.5120(2) o, q = 0.54206(8)a* + 0.79330(8)b*]. In both structures, the antiphase Ca and (Gd,Eu) occupancy modulations indicate that the ordering between the A cations and vacancies also induces partial Ca/(Gd,Eu) cation ordering. Further increase of the Gd3þ content up to x = 0.567 leads to the formation of a monoclinic phase (space group C2/c) with the Eu2/3WO4-type structure. Despite the difference in the cation-vacancy ordering patterns, all materials in the series demonstrate very similar quantum efficiency and luminescence decay lifetimes. However, the difference in the local coordination environment of the A cation species noticeably affects the line width and the multiplet splitting of the 4f6-4f6 transitions.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000397997300045 Publication Date 2017-02-16  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0925-8388 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (down) 3.133 Times cited 2 Open Access OpenAccess  
  Notes This research was supported by FWO (Flanders Research Foundation, project G039211N). V.A.M. is grateful for financial support of the Russian Foundation for Basic Research (Grant 15-03-07741).We are grateful to the ESRF for granting the beamtime at the ID22 beamline and to Andy Fitch for the support during the experiment. Approved Most recent IF: 3.133  
  Call Number EMAT @ emat @ c:irua:142367 Serial 4581  
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Author Zaghi, A.E.; Buffière, M.; Brammertz, G.; Batuk, M.; Lenaers, N.; Kniknie, B.; Hadermann, J.; Meuris, M.; Poortmans, J.; Vleugels, J. pdf  url
doi  openurl
  Title Mechanical synthesis of high purity Cu-In-Se alloy nanopowder as precursor for printed CISe thin film solar cells Type A1 Journal article
  Year 2014 Publication Advanced powder technology Abbreviated Journal Adv Powder Technol  
  Volume 25 Issue 4 Pages 1254-1261  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Mechanical alloying and ball milling are low cost, up-scalable techniques for the preparation of high purity chalcogenide nanopowders to be used as precursor material for printing thin film solar cells. In this study, high purity copper indium selenium (Cu-In-Se) alloy nanopowders with 20-200 nm particle size were synthesized from macroscopic elemental Cu, In and Se powders via mechanical alloying and planetary ball milling. The particle size distribution, morphology, composition, and purity level of the synthesized Cu-In-Se alloy nanopowders were investigated. Thin Cu-In-Se alloy nanopowder ink coatings, deposited on Mo-coated glass substrates by doctor blading, were converted into a CuInSe2 semiconductor film by selenization heat treatment in Se vapor. The CuInSe2 film showed semiconducting band gap around 1 eV measured by photoluminescence spectroscopy. CuInSe2 absorber layer based thin film solar cell devices were fabricated to assess their performance. The solar cell device showed a total efficiency of 4.8%, as measured on 0.25 cm(2) area cell. (c) 2014 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Zeist Editor  
  Language Wos 000341871700015 Publication Date 2014-03-17  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0921-8831; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (down) 2.659 Times cited 10 Open Access  
  Notes Approved Most recent IF: 2.659; 2014 IF: 2.638  
  Call Number UA @ lucian @ c:irua:119896 Serial 1977  
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Author Guzzinati, G.; Altantzis, T.; Batuk, M.; De Backer, A.; Lumbeeck, G.; Samaee, V.; Batuk, D.; Idrissi, H.; Hadermann, J.; Van Aert, S.; Schryvers, D.; Verbeeck, J.; Bals, S. url  doi
openurl 
  Title Recent Advances in Transmission Electron Microscopy for Materials Science at the EMAT Lab of the University of Antwerp Type A1 Journal article
  Year 2018 Publication Materials Abbreviated Journal Materials  
  Volume 11 Issue 11 Pages 1304  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract The rapid progress in materials science that enables the design of materials down to the nanoscale also demands characterization techniques able to analyze the materials down to the same scale, such as transmission electron microscopy. As Belgium’s foremost electron microscopy group, among the largest in the world, EMAT is continuously contributing to the development of TEM techniques, such as high-resolution imaging, diffraction, electron tomography, and spectroscopies, with an emphasis on quantification and reproducibility, as well as employing TEM methodology at the highest level to solve real-world materials science problems. The lab’s recent contributions are presented here together with specific case studies in order to highlight the usefulness of TEM to the advancement of materials science.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000444112800041 Publication Date 2018-07-28  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1996-1944 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (down) 2.654 Times cited 15 Open Access OpenAccess  
  Notes Fonds Wetenschappelijk Onderzoek, G.0502.18N, G.0267.18N, G.0120.12N, G.0365.15N, G.0934.17N, S.0100.18N AUHA13009 ; European Research Council, COLOURATOM 335078 ; Universiteit Antwerpen, GOA Solarpaint ; G. Guzzinati, T. Altantzis and A. De Backer have been supported by postdoctoral fellowship grants from the Research Foundation Flanders (FWO). Funding was also received from the European Research Council (starting grant no. COLOURATOM 335078), the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement no. 770887), the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0502.18N, G.0267.18N, G.0120.12N, G.0365.15N, G.0934.17N, S.0100.18N, G.0401.16N) and from the University of Antwerp through GOA project Solarpaint. Funding for the TopSPIN precession system under grant AUHA13009, as well as for the Qu-Ant-EM microscope, is acknowledged from the HERCULES Foundation. H. Idrissi is mandated by the Belgian National Fund for Scientific Research (F.R.S.-FNRS). (ROMEO:green; preprint:; postprint:can ; pdfversion:can); saraecas; ECAS_Sara; Approved Most recent IF: 2.654  
  Call Number EMAT @ emat @c:irua:153737UA @ admin @ c:irua:153737 Serial 5064  
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Author Batuk, M.; Tyablikov, O.A.; Tsirlin, A.A.; Kazakov, S.M.; Rozova, M.G.; Pokholok, K.V.; Filimonov, D.S.; Antipov, E.V.; Abakumov, A.M.; Hadermann, J. pdf  doi
openurl 
  Title Structure and magnetic properties of a new anion-deficient perovskite Pb2Ba2BiFe4ScO13 with crystallographic shear structure Type A1 Journal article
  Year 2013 Publication Materials research bulletin Abbreviated Journal Mater Res Bull  
  Volume 48 Issue 9 Pages 3459-3465  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Pb2Ba2BiFe4ScO13, a new n = 5 member of the oxygen-deficient perovskite-based A(n)B(n)O(3n-2) homologous series, was synthesized using a solid-state method. The crystal structure of Pb2Ba2BiFe4ScO13 was investigated by a combination of synchrotron X-ray powder diffraction, electron diffraction, high-angle annular dark-field scanning transmission electron microscopy and Mossbauer spectroscopy. At 900 K, it crystallizes in the Ammm space group with the unit cell parameters a = 5.8459(1) angstrom, b = 4.0426(1) angstrom, and c=27.3435(1) angstrom. In the Pb2Ba2BiFe4ScO13 structure, quasi-two-dimensional perovskite blocks are periodically interleaved with 1/2[1 1 0] ((1) over bar 0 1)(p) crystallographic shear (CS) planes. At the CS planes, the corner-sharing FeO6 octahedra are transformed into chains of edge-sharing FeO5 distorted tetragonal pyramids. B-positions of the perovskite blocks between the CS planes are jointly occupied by Fe3+ and Sc3+. The chains of the FeO5 pyramids and (Fe,Sc)O-6 octahedra delimit six-sided tunnels that are occupied by double columns of cations with a lone electron pair (Pb2+). The remaining A-cations (Bi3+, Ba2+) occupy positions in the perovskite block. According to the magnetic susceptibility measurements, Pb2Ba2BiFe4ScO13 is antiferromagnetically ordered below T-N approximate to 350 K. (C) 2013 Elsevier Ltd. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication New York, N.Y. Editor  
  Language Wos 000322354000076 Publication Date 2013-05-17  
  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 (down) 2.446 Times cited 2 Open Access  
  Notes Approved Most recent IF: 2.446; 2013 IF: 1.968  
  Call Number UA @ lucian @ c:irua:109756 Serial 3282  
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Author Korneychik, O.E.; Batuk, M.; Abakumov, A.M.; Hadermann, J.; Rozova, M.G.; Sheptyakov, D.V.; Pokholok, K.V.; Filimonov, D.S.; Antipov, E.V. pdf  doi
openurl 
  Title Pb2.85Ba2.15Fe4SnO13 : a new member of the AnBnO3n-2 anion-deficient perovskite-based homologous series Type A1 Journal article
  Year 2011 Publication Journal of solid state chemistry Abbreviated Journal J Solid State Chem  
  Volume 184 Issue 12 Pages 3150-3157  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Pb2.85Ba2.15Fe4SnO13, a new n=5 member of the anion-deficient perovskite based AnBnO3n−2 (A=Pb, Ba, B=Fe, Sn) homologous series, was synthesized by the solid state method. The crystal structure of Pb2.85Ba2.15Fe4SnO13 was investigated using a combination of neutron powder diffraction, electron diffraction, high angle annular dark field scanning transmission electron microscopy and Mössbauer spectroscopy. It crystallizes in the Ammm space group with unit cell parameters a=5.7990(1) Å, b=4.04293(7) Å and c=26.9561(5) Å. The Pb2.85Ba2.15Fe4SnO13 structure consists of quasi two-dimensional perovskite blocks separated by 1/2[110](1̄01)p crystallographic shear (CS) planes. The corner-sharing FeO6 octahedra at the CS planes are transformed into edge-sharing FeO5 distorted tetragonal pyramids. The octahedral positions in the perovskite blocks between the CS planes are jointly taken up by Fe and Sn, with a preference of Sn towards the position at the center of the perovskite block. The chains of FeO5 pyramids and (Fe,Sn)O6 octahedra of the perovskite blocks delimit six-sided tunnels at the CS planes occupied by double chains of Pb atoms. The compound is antiferromagnetically ordered below TN=368±15 K.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos 000297662500003 Publication Date 2011-09-30  
  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 (down) 2.299 Times cited 7 Open Access  
  Notes Approved Most recent IF: 2.299; 2011 IF: 2.159  
  Call Number UA @ lucian @ c:irua:94013 Serial 3550  
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Author Batuk, M.; Batuk, D.; Abakumov, A.M.; Hadermann, J. pdf  doi
openurl 
  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 (down) 2.299 Times cited 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 Ben Hafsia, A.; Hendrickx, M.; Batuk, M.; Khitouni, M.; Hadermann, J.; Greneche, J.-M.; Rammeh, N. pdf  doi
openurl 
  Title Crystal structure study of manganese and titanium substituted BaLaFe2O6-δ Type A1 Journal article
  Year 2017 Publication Journal of solid state chemistry Abbreviated Journal J Solid State Chem  
  Volume 251 Issue 251 Pages 186-193  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Barium lanthanum ferrite and four Mn/Ti substituted materials were synthesized by the sol-gel method. The crystal structure of the materials was studied by a combination of X-ray powder diffraction, electron diffraction, scanning transmission electron microscopy and 57Fe Mössbauer spectrometry. BaLaFe2O6-δ has a cubic perovskite structure and Ba0.7La1.3FeMnO6-δ is distorted perovskite with the R-3c symmetry, both from electron diffraction and X-ray powder diffraction. However, according to transmission electron microscopy, the crystals of BaLaFeTiO6-δ, BaLaFeTi0.5Mn0.5O6-δ, and BaLaFe0.5Ti0.5MnO6-δ consist of nanodomains with different symmetries (Pm3m next to R-3c due to octahedral tilts), whereas the bulk X-ray powder diffraction patterns for these compounds correspond to the simple cubic structure. 57Fe Mössbauer spectrometry confirms that all materials contain high spin state Fe3+ ions which are strongly influenced by the chemical disorder

resulting from various cationic environments.
 
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000402581200024 Publication Date 2017-04-20  
  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 (down) 2.299 Times cited Open Access Not_Open_Access  
  Notes This study has been supported by the Tunisian Ministry of Higher Education and Scientific Research and by the University of Antwerp BOF Grant 33024 funding scheme. Approved Most recent IF: 2.299  
  Call Number EMAT @ emat @ c:irua:143988 Serial 4582  
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Author Istomin, S.Y.; Morozov, A.V.; Abdullayev, M.M.; Batuk, M.; Hadermann, J.; Kazakov, S.M.; Sobolev, A.V.; Presniakov, I.A.; Antipov, E.V. pdf  doi
openurl 
  Title High-temperature properties of (La,Ca)(Fe,Mg,Mo)O3-\delta perovskites as prospective electrode materials for symmetrical SOFC Type A1 Journal article
  Year 2018 Publication Journal of solid state chemistry Abbreviated Journal J Solid State Chem  
  Volume 258 Issue 258 Pages 1-10  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract La1-yCayFe0.5+x(Mg,Mo)(0.5-x)O3-delta oxides with the orthorhombic GdFeO3-type perovskite structure have been synthesized at 1573 K. Transmission electron microscopy study for selected samples shows the coexistence of domains of perovskite phases with ordered and disordered B-cations. Mossbauer spectroscopy studies performed at 300 K and 573 K show that while compositions with low Ca-content (La0.55Ca0.45Fe0.5Mg0.2625Mo0.2375O3-delta and La0.5Ca0.5Fe0.6Mg0.175Mo0.225O3-delta) are nearly oxygen stoichiometric, La0.2Ca0.8Fe0.5Mg0.2625Mo0.2375O3-delta is oxygen deficient with delta approximate to 0.15. Oxides are stable in reducing atmosphere (Ar/H-2, 8%) at 1173 K for 12 h. No additional phases have been observed at XRPD patterns of all studied perovskites and Ce1-xGdxO2-x/2 electrolyte mixtures treated at 1173-1373K, while Fe-rich compositions (x >= 0.1) react with Zr1-xYxO2-x/2 electrolyte above 1273 K. Dilatometry studies reveal that all samples show rather low thermal expansion coefficients (TECs) in air of 11.4-12.7 ppm K-1. In reducing atmosphere their TECs were found to increase up to 12.1-15.4 ppm K-1 due to chemical expansion effect. High-temperature electrical conductivity measurements in air and Ar/H-2 atmosphere show that the highest conductivity is observed for Fe- and Ca-rich compositions. Moderate values of electrical conductivity and TEC together with stability towards chemical interaction with typical SOFC electrolytes make novel Fe-containing perovskites promising electrode materials for symmetrical solid oxide fuel cell.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos 000423650400001 Publication Date 2017-10-11  
  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 (down) 2.299 Times cited 5 Open Access Not_Open_Access  
  Notes ; This work was financially supported by Russian Science Foundation (project number 16-13-10327). ; Approved Most recent IF: 2.299  
  Call Number UA @ lucian @ c:irua:149283 Serial 4936  
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