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| Author | Paria Sena, R.; Babaryk, A.A.; Khainakov, S.; Garcia-Granda, S.; Slobodyanik, N.S.; Van Tendeloo, G.; Abakumov, A.M.; Hadermann, J. | ||||
| Title | A pseudo-tetragonal tungsten bronze superstructure: a combined solution of the crystal structure of K6.4(Nb,Ta)36.3O94 with advanced transmission electron microscopy and neutron diffraction | Type | A1 Journal article | ||
| Year | 2016 | Publication | Journal of the Chemical Society : Dalton transactions | Abbreviated Journal | Dalton T |
| Volume | 45 | Issue | 45 | Pages | 973-979 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | The crystal structure of the K6.4Nb28.2Ta8.1O94 pseudo-tetragonal tungsten bronze-type oxide was determined using a combination of X-ray powder diffraction, neutron diffraction and transmission electron microscopy techniques, including electron diffraction, high angle annular dark field scanning transmission electron microscopy (HAADF-STEM), annular bright field STEM (ABF-STEM) and energy-dispersive X-ray compositional mapping (STEM-EDX). The compound crystallizes in the space group Pbam with unit cell parameters a = 37.468(9) A, b = 12.493(3) A, c = 3.95333(15) A. The structure consists of corner sharing (Nb,Ta)O6 octahedra forming trigonal, tetragonal and pentagonal tunnels. All tetragonal tunnels are occupied by K(+) ions, while 1/3 of the pentagonal tunnels are preferentially occupied by Nb(5+)/Ta(5+) and 2/3 are occupied by K(+) in a regular pattern. A fractional substitution of K(+) in the pentagonal tunnels by Nb(5+)/Ta(5+) is suggested by the analysis of the HAADF-STEM images. In contrast to similar structures, such as K2Nb8O21, also parts of the trigonal tunnels are fractionally occupied by K(+) cations. | ||||
| Address | Electron Microscopy for Materials Research (EMAT), University of Antwerp, Groenenborgerlaan 171, B-2020, Antwerp, Belgium. joke.hadermann@uantwerpen.be babaryk@univ.kiev.ua | ||||
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| Language | English | Wos | 000367614700018 | Publication Date | 2015-11-23 |
| Series Editor | Series Title | Abbreviated Series Title | |||
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| ISSN | 1477-9226 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 4.029 | Times cited | 6 | Open Access  |
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| Notes | We thank Dr E. Suard and Dr O. Fabello for assistance in collecting the neutron diffraction data. R.P.S. acknowledges funding from the European Research Council under the 7th Framework Program (FP7), ERC Grant No. 246791-COUNTATOMS. The titan microscope was partly funded by the Hercules fund from the Flemish Government. The authors acknowledge financial support from the European Union under the Seventh Framework Program under a contract for an Integrated Infrastructure Initiative. Reference No. 312483-ESTEEM2. AAB acknowledges the JSPDS ICDD Grant-in-Aid program (12-02).; esteem2jra1; esteem2jra2 | Approved | Most recent IF: 4.029 | ||
| Call Number | c:irua:130408 c:irua:130408 | Serial | 3998 | ||
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| Author | Fedotov, S.S.; Khasanova, N.R.; Samarin, A.S.; Drozhzhin, O.A.; Batuk, D.; Karakulina, O.M.; Hadermann, J.; Abakumov, A.M.; Antipov, E.V. | ||||
| Title | AVPO4F (A = Li, K): A 4 V Cathode Material for High-Power Rechargeable Batteries | Type | A1 Journal article | ||
| Year | 2016 | Publication | Chemistry of materials | Abbreviated Journal | Chem Mater |
| Volume | 28 | Issue | 28 | Pages | 411-415 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | A novel potassium-based fluoride-phosphate, KVPO4F, with a KTiOPO4 (KTP) type structure is synthesized and characterized. About 85% of potassium has been electrochemically extracted on oxidation producing a cathode material with attractive performance for Li-ion batteries. The material operates at the electrode potential near 4V vs Li/Li+ exhibiting a sloping voltage profile, extremely low polarization, small volume change of about 2% and excellent rate capability, maintaining more than 75% of the initial capacity at 40C discharge rate without significant fading. | ||||
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| Language | Wos | 000368949900002 | Publication Date | 2016-01-04 | |
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| ISSN | 0897-4756 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 9.466 | Times cited | 46 | Open Access |
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| Notes | The authors kindly thank Dr. S. N. Putilin for XRD measurements, Dr. O. A. Shlyakhtin for the assistance in cryochemical synthesis, Ph.D. students A. A. Sadovnikov and E. A. Karpukhina for SEM imaging and FTIR spectra respectively. The work was partly supported by Russian Science Foundation (grant 16-19-00190), Skoltech Center for Electrochemical Energy Storage and Moscow State University Devel-opment Program up to 2020. J. Hadermann, O.M. Karakulina and A.M. Abakumov acknowledge support from FWO under grant G040116N. | Approved | Most recent IF: 9.466 | ||
| Call Number | c:irua:131583 | Serial | 4001 | ||
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| Author | Drozhzhin, O.A.; Sumanov, V.D.; Karakulina, O.M.; Abakumov, A.M.; Hadermann, J.; Baranov, A.N.; Stevenson, K.J.; Antipov, E.V. | ||||
| Title | Switching between solid solution and two-phase regimes in the Li1-xFe1-yMnyPO4 cathode materials during lithium (de)insertion: combined PITT, in situ XRPD and electron diffraction tomography study | Type | A1 Journal article | ||
| Year | 2016 | Publication | Electrochimica acta | Abbreviated Journal | Electrochim Acta |
| Volume | 191 | Issue | 191 | Pages | 149-157 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | The electrochemical properties and phase transformations during (de)insertion of Li+ in LiFePO4, LiFe0.9Mn0.1PO4 and LiFe0.5Mn0.5PO4 are studied by means of galvanostatic cycling, potential intermittent titration technique (PITT) and in situ X-ray powder diffraction. Different modes of switching between the solid solution and two-phase regimes are revealed which are influenced by the Mn content in Li1-xFe1-yMnyPO4. Additionally, an increase in electrochemical capacity with the Mn content is observed at high rates of galvanostatic cycling (10C, 20C), which is in good agreement with the numerically estimated contribution of the solid solution mechanism determined from PITT data. The observed asymmetric behavior of the phase transformations in Li1-xFe0.5Mn0.5PO4 during charge and discharge is discussed. For the first time, the crystal structures of electrochemically deintercalated Li1-xFe0.5Mn0.5PO4 with different Li content – LiFe0.5Mn0.5PO4, Li0.5Fe0.5Mn0.5PO4 and Li0.1Fe0.5Mn0.5PO4 – are refined, including the occupancy factors of the Li position. This refinement is done using electron diffraction tomography data. The crystallographic analyses of Li1-xFe0.5Mn0.5PO4 reveal that at x = 0.5 and 0.9 the structure retains the Pnma symmetry and the main motif of the pristine x = 0 structure without noticeable short range order effects. | ||||
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| Language | Wos | 000371143200018 | Publication Date | 2016-01-13 | |
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| ISSN | 0013-4686 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 4.798 | Times cited | 27 | Open Access |
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| Notes | This work was supported by the Russian Foundation of Basic Research (grants No. 14-29-04064 and 14-03-31473), Skolkovo Institute of Science and Technology, and the Lomonosov Moscow State University Program of Development. J. Hadermann, O. M. Karakulina and A. M. Abakumov acknowl- edge support from FWO under grant G040116N. | Approved | Most recent IF: 4.798 | ||
| Call Number | c:irua:131911 | Serial | 4032 | ||
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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 | ||||
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| Language | English | Wos | 000369356800031 | Publication Date | 2016-01-09 |
| Series Editor | Series Title | Abbreviated Series Title | |||
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| ISSN | 0020-1669 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 4.857 | Times cited | 3 | Open Access |
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| 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 | Fedotov, S.S.; Kuzovchikov, S.M.; Khasanova, N.R.; Drozhzhin, O.A.; Filimonov, D.S.; Karakulina, O.M.; Hadermann, J.; Abakumov, A.M.; Antipov, E.V. | ||||
| Title | Synthesis, structure and electrochemical properties of LiNaCo0.5Fe0.5PO4F fluoride-phosphate | Type | A1 Journal article | ||
| Year | 2016 | Publication | Journal of solid state chemistry | Abbreviated Journal | J Solid State Chem |
| Volume | 242 | Issue | 242 | Pages | 70-77 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | LiNaCo 0.5 Fe 0.5 PO 4 F fluoride-phosphate was synthesized via conventional solid-state and novel freeze-drying routes. The crystal structure was refined based on neutron powder diffraction (NPD) data and validated by electron diffraction (ED) and high-resolution transmission electron microscopy (HRTEM). The alkali ions are ordered in LiNaCo 0.5 Fe 0.5 PO 4 F and the transition metals jointly occupy the same crystallographic sites. The oxidation state and oxygen coordination environment of the Fe atoms were verified by 57 Fe Mössbauer spectroscopy. Electrochemical tests of the LiNaCo 0.5 Fe 0.5 PO 4 F cathode material demonstrated a reversible activity of the Fe 3+ /Fe 2+ redox couple at the electrode potential near 3.4 V and minor activity of the Co 3+ /Co 2+ redox couple over 5 V vs Li/Li + . The material exhibits a good capacity retention in the 2.4÷4.6 V vs Li/Li + potential range with the delivered discharge capacity of more than 82% (theo.) regarding Fe 3+ /Fe 2+ . | ||||
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| Language | Wos | 000383304900010 | Publication Date | 2016-02-27 | |
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| ISSN | 0022-4596 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.299 | Times cited | 1 | Open Access |
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| Notes | The authors kindly thank Dr. O. A. Shlyakhtin for the assistance in the freeze-drying synthesis. We are grateful to the Laboratory for Neutron Scattering and Imaging (NLS) at the Paul Scherrer Institut (Villigen, Switzerland) for granting beam time at the HRPT diffractometer and to Dr. D. V. Sheptyakov for the technical support during the experiment. The work was partly supported by Russian Foundation for Basic Research (RFBR grant 13-03-00495a, 14-29-04064 ofim, 16-33-01131 mola), Skoltech Center for Electrochemical Energy Storage and Moscow State University Development Program up to 2020. J. Hadermann, O.M. Karakulina and A.M. Abakumov acknowledge support from FWO under grant G040116N. | Approved | Most recent IF: 2.299 | ||
| Call Number | c:irua:133776 | Serial | 4075 | ||
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| Author | Zhang, F.; Batuk, M.; Hadermann, J.; Manfredi, G.; Mariën, A.; Vanmeensel, K.; Inokoshi, M.; Van Meerbeek, B.; Naert, I.; Vleugels, J. | ||||
| Title | Effect of cation dopant radius on the hydrothermal stability of tetragonal zirconia: Grain boundary segregation and oxygen vacancy annihilation | Type | A1 Journal article | ||
| Year | 2016 | Publication | Acta materialia | Abbreviated Journal | Acta Mater |
| Volume | 106 | Issue | 106 | Pages | 48-58 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | The hydrothermal aging stability of 3Y-TZP-xM2O3 (M = La, Nd, Sc) was investigated as a function of 0.02–5 mol% M2O3 dopant content and correlated to the overall phase content, t-ZrO2 lattice parameters, grain size distribution, grain boundary chemistry and ionic conductivity. The increased aging stability with increasing Sc2O3 content and the optimum content of 0.4–0.6 mol% Nd2O3 or 0.2–0.4 mol% La2O3, resulting in the highest aging resistance, could be directly related to the constituent phases and the lattice parameters of the remaining tetragonal zirconia. At low M2O3 dopant contents ≤0.4 mol%, the different aging behavior of tetragonal zirconia was attributed to the defect structure of the zirconia grain boundary which was influenced by the dopant cation radius. It was observed that the grain boundary ionic resistivity and the aging resistance followed the same trend: La3+ > Nd3+ > Al3+ > Sc3+, proving that hydrothermal aging is driven by the diffusion of water-derived mobile species through the oxygen vacancies. Accordingly, we elucidated the underlying mechanism by which a larger trivalent cation segregating at the zirconia grain boundary resulted in a higher aging resistance. |
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| Language | Wos | 000371650300006 | Publication Date | 2016-01-08 | |
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| ISSN | 1359-6454 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 5.301 | Times cited | 37 | Open Access |
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| Notes | The authors acknowledge the Research Fund of KU Leuven 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). | Approved | Most recent IF: 5.301 | ||
| Call Number | c:irua:132435 | Serial | 4076 | ||
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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 | ||||
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| Language | English | Wos | 000367723400031 | Publication Date | 2015-10-21 |
| Series Editor | Series Title | Abbreviated Series Title | |||
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| ISSN | 1433-7851 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 11.994 | Times cited | 3 | Open Access |
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| 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 | Mikhailova, D.; Karakulina, O.M.; Batuk, D.; Hadermann, J.; Abakumov, A.M.; Herklotz, M.; Tsirlin, A.A.; Oswald, S.; Giebeler, L.; Schmidt, M.; Eckert, J.; Knapp, M.; Ehrenberg, H. | ||||
| Title | Layered-to-Tunnel Structure Transformation and Oxygen Redox Chemistry in LiRhO2upon Li Extraction and Insertion | Type | A1 Journal article | ||
| Year | 2016 | Publication | Inorganic chemistry | Abbreviated Journal | Inorg Chem |
| Volume | 55 | Issue | 55 | Pages | 7079-7089 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Layered Li(M,Li)O2 (where M is a transition metal) ordered rock-salt-type structures are used in advanced metal-ion batteries as one of the best hosts for the reversible intercalation of Li ions. Besides the conventional redox reaction involving oxidation/reduction of the M cation upon Li extraction/insertion, creating oxygen-located holes because of the partial oxygen oxidation increases capacity while maintaining the oxidized oxygen species in the lattice through high covalency of the M–O bonding. Typical degradation mechanism of the Li(M,Li)O2 electrodes involves partially irreversible M cation migration toward the Li positions, resulting in gradual capacity/voltage fade. Here, using LiRhO2 as a model system (isostructural and isoelectronic to LiCoO2), for the first time, we demonstrate an intimate coupling between the oxygen redox and M cation migration. A formation of the oxidized oxygen species upon electrochemical Li extraction coincides with transformation of the layered Li1–xRhO2 structure into the γ-MnO2-type rutile–ramsdellite intergrowth LiyRh3O6 structure with rutile-like [1 × 1] channels along with bigger ramsdellite-like [2 × 1] tunnels through massive and concerted Rh migration toward the empty positions in the Li layers. The oxidized oxygen dimers with the O–O distances as short as 2.26 Å are stabilized in this structure via the local Rh–O configuration reminiscent to that in the μ-peroxo-μ-hydroxo Rh complexes. The LiyRh3O6 structure is remarkably stable upon electrochemical cycling illustrating that proper structural implementation of the oxidized oxygen species can open a pathway toward deliberate employment of the anion redox chemistry in high-capacity/high-voltage positive electrodes for metal-ion batteries. Upon chemical or electrochemical oxidation, layered LiRhO2 shows a unique structural transformation that involves both cation migration and oxidation of oxygen resulting in a stable tunnel-like rutile−ramsdellite intergrowth LiyRh3O6 structure. This structure demonstrates excellent performance with the steady and reversible capacity of ∼200 mAh/g. The stability of LiyRh3O6 is rooted in the accommodation of partially oxidized oxygen species through the formation of short O−O distances that are compatible with the connectivity of RhO6 octahedra. | ||||
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| Language | Wos | 000380181400035 | Publication Date | 2016-07-18 | |
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| ISSN | 0020-1669 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 4.857 | Times cited | 12 | Open Access |
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| Notes | Bundesministerium fur Bildung und Forschung, 03SF0477B ; Fonds Wetenschappelijk Onderzoek, G040116N ; | Approved | Most recent IF: 4.857 | ||
| Call Number | EMAT @ emat @ c:irua:140848 | Serial | 4424 | ||
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| Author | Cassidy, S.J.; Batuk, M.; Batuk, D.; Hadermann, J.; Woodruff, D.N.; Thompson, A.L.; Clarke, S.J. | ||||
| Title | Complex Microstructure and Magnetism in Polymorphic CaFeSeO | Type | A1 Journal article | ||
| Year | 2016 | Publication | Inorganic chemistry | Abbreviated Journal | Inorg Chem |
| Volume | 55 | Issue | 55 | Pages | 10714-10726 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | The structural complexity of the antiferromagnetic oxide selenide CaFeSeO is described. The compound contains puckered FeSeO layers composed of FeSe2O2 tetrahedra sharing all their vertexes. Two polymorphs coexist that can be derived from an archetype BaZnSO structure by cooperative tilting of the FeSe2O2 tetrahedra. The polymorphs differ in the relative arrangement of the puckered layers of vertex-linked FeSe2O2 tetrahedra. In a noncentrosymmetric Cmc21 polymorph (a = 3.89684(2) A, b = 13.22054(8) A, c = 5.93625(2) A) the layers are related by the C-centering translation, while in a centrosymmetric Pmcn polymorph, with a similar cell metric (a = 3.89557(6) A, b = 13.2237(6) A, c = 5.9363(3) A), the layers are related by inversion. The compound shows long-range antiferromagnetic order below a Neel temperature of 159(1) K with both polymorphs showing antiferromagnetic coupling via Fe-O-Fe linkages and ferromagnetic coupling via Fe-Se-Fe linkages within the FeSeO layers. The magnetic susceptibility also shows evidence for weak ferromagnetism which is modeled in the refinements of the magnetic structure as arising from an uncompensated spin canting in the noncentrosymmetric polymorph. There is also a spin glass component to the magnetism which likely arises from the disordered regions of the structure evident in the transmission electron microscopy. | ||||
| Address | Department of Chemistry, Inorganic Chemistry Laboratory, University of Oxford , South Parks Road, Oxford OX1 3QR, United Kingdom | ||||
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| Language | English | Wos | 000385785700085 | Publication Date | 2016-10-05 |
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| ISSN | 0020-1669 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 4.857 | Times cited | 6 | Open Access |
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| Notes | We acknowledge the financial support of the EPSRC (Grants EP/I017844/1 and EP/M020517/1), the Leverhulme Trust (RPG-2014-221), and the Diamond Light Source (studentship support for S. J. Cassidy). We thank the ESTEEM2 network for enabling the electron microscopy investigations and the ISIS facility and the Diamond Light Source Ltd. for the award of beam time. We thank Dr. P. Manuel for assistance on WISH, Dr. R. I. Smith for assistance on GEM and POLARIS, and Dr. C. Murray and Dr. A. Baker for assistance on I11. | Approved | Most recent IF: 4.857 | ||
| Call Number | EMAT @ emat @ c:irua:136823 | Serial | 4312 | ||
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| Author | Zhang, F.; Inokoshi, M.; Batuk, M.; Hadermann, J.; Naert, I.; Van Meerbeek, B.; Vleugels, J. | ||||
| 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 | ||||
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| Language | English | Wos | 000389516400003 | Publication Date | 2016-10-06 |
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0109-5641 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 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 | ||
| Permanent link to this record | |||||
| Author | Karakulina, O.M.; Khasanova, N.R.; Drozhzhin, O.A.; Tsirlin, A.A.; Hadermann, J.; Antipov, E.V.; Abakumov, A.M. | ||||
| Title | Antisite Disorder and Bond Valence Compensation in Li2FePO4F Cathode for Li-Ion Batteries | Type | A1 Journal article | ||
| Year | 2016 | Publication | Chemistry Of Materials | Abbreviated Journal | Chem Mater |
| Volume | 28 | Issue | 28 | Pages | 7578-7581 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | |||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000387518500004 | Publication Date | 2016-11-08 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0897-4756 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 9.466 | Times cited | 10 | Open Access |
|
| Notes | Russian Science Foundation, 16-19-00190 ; Fonds Wetenschappelijk Onderzoek, G040116N ; | Approved | Most recent IF: 9.466 | ||
| Call Number | EMAT @ emat @ c:irua:139170 c:irua:138599 | Serial | 4320 | ||
| Permanent link to this record | |||||
| Author | Callaert, C.; Bercx, M.; Lamoen, D.; Hadermann, J. | ||||
| Title | Interstitial defects in the van der Waals gap of Bi2Se3 | Type | A1 Journal article | ||
| Year | 2019 | Publication | Acta Crystallographica. Section B: Structural Science, Crystal Engineering and Materials (Online) | Abbreviated Journal | Acta Crystallogr B |
| Volume | 75 | Issue | 4 | Pages | 717-732 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Bi<sub>2</sub>Se<sub>3</sub>is a thermoelectric material and a topological insulator. It is slightly conducting in its bulk due to the presence of defects and by controlling the defects different physical properties can be fine tuned. However, studies of the defects in this material are often contradicting or inconclusive. Here, the defect structure of Bi<sub>2</sub>Se<sub>3</sub>is studied with a combination of techniques: high-resolution scanning transmission electron microscopy (HR-STEM), high-resolution energy-dispersive X-ray (HR-EDX) spectroscopy, precession electron diffraction tomography (PEDT), X-ray diffraction (XRD) and first-principles calculations using density functional theory (DFT). Based on these results, not only the observed defects are discussed, but also the discrepancies in results or possibilities across the techniques. STEM and EDX revealed interstitial defects with mainly Bi character in an octahedral coordination in the van der Waals gap, independent of the applied sample preparation method (focused ion beam milling or cryo-crushing). The inherent character of these defects is supported by their observation in the structure refinement of the EDT data. Moreover, the occupancy probability of the defects determined by EDT is inversely proportional to their corresponding DFT calculated formation energies. STEM also showed the migration of some atoms across and along the van der Waals gap. The kinetic barriers calculated using DFT suggest that some paths are possible at room temperature, while others are most probably beam induced. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000480512600024 | Publication Date | 2019-08-01 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2052-5206 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.032 | Times cited | Open Access |
||
| Notes | University of Antwerp, 31445 ; Acknowledgements We thank Artem M. Abakumov for providing the original Bi2Se3 sample and are also very grateful to Christophe Vandevelde for trying repeatedly to get good single crystal X-ray diffraction data out of each of our failed attempts at making an undeformed single crystal. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the FWO-Vlaanderen and the Flemish Government-department EWI. | Approved | Most recent IF: 2.032 | ||
| Call Number | EMAT @ emat @c:irua:161847 | Serial | 5295 | ||
| Permanent link to this record | |||||
| Author | Gvozdetskyi, V.; Bhaskar, G.; Batuk, M.; Zhao, X.; Wang, R.; Carnahan, S.L.; Hanrahan, M.P.; Ribeiro, R.A.; Canfield, P.C.; Rossini, A.J.; Wang, C.-Z.; Ho, K.-M.; Hadermann, J.; Zaikina, J.V. | ||||
| Title | Computationally Driven Discovery of a Family of Layered LiNiB Polymorphs | Type | A1 Journal article | ||
| Year | 2019 | Publication | Angewandte Chemie: international edition in English | Abbreviated Journal | Angew Chem Int Edit |
| Volume | 58 | Issue | 44 | Pages | 15855-15862 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Two novel lithium nickel boride polymorphs RT-LiNiB and HT-LiNiB with layered crystal structures are reported. This family of compounds was theoretically predicted by using the adaptive genetic algorithm (AGA) and subsequently synthesized via a hydride route with LiH precursor as a lithium source. Being unique among the known ternary transition metal borides, the LiNiB structures feature Li layers alternating with nearly planar [NiB] layers, composed of Ni hexagonal rings centered by B-B pairs. A comprehensive study using a combination of single crystal/synchrotron powder X-ray diffraction data, solid-state 7Li and 11B NMR, scanning transmission electron microscopy, quantum chemistry calculations, and magnetism has shed light on the intrinsic features of these polymorphic compounds. The unique layered structures of LiNiB compounds make them ultimate precursors to further study their exfoliation, paving a way toward two-dimensional transition metal borides, MBenes. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000491219600038 | Publication Date | 2019-10-28 | |
| 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 | Open Access |
||
| Notes | the Gordon and Betty Moore Foundation’s EPiQS Initiative through Grant GBMF4411. The Ames Laboratory is operated for the U.S. Department of Energy by Iowa State University under contract #DE-AC02-07CH11358. Use of the Advanced Photon Source at Argonne National Laboratory was supported by the U. S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357. | Approved | Most recent IF: 11.994 | ||
| Call Number | EMAT @ emat @c:irua:164752 | Serial | 5433 | ||
| Permanent link to this record | |||||
| Author | Jin, L.; Batuk, M.; Kirschner, F.K.K.; Lang, F.; Blundell, S.J.; Hadermann, J.; Hayward, M.A. | ||||
| 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 | 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 | ||
| Permanent link to this record | |||||
| Author | Chin, C.–M.; Battle, P.D.; Hunter, E.C.; Avdeev, M.; Hendrickx, M.; Hadermann, J. | ||||
| Title | Magnetic properties of La3Ni2Sb Ta Nb1––O9; from relaxor to spin glass | Type | A1 Journal article | ||
| Year | 2019 | Publication | Journal of solid state chemistry (Print) | Abbreviated Journal | Journal of Solid State Chemistry |
| Volume | 273 | Issue | Pages | 175-185 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Neutron diffraction experiments conducted at 5 K in a magnetic field 0 < H/kOe < 50 have shown that the monoclinic perovskite La3Ni2TaO9 behaves as a relaxor ferromagnet. Compositions in the series La3Ni2SbxTayNb1–x–yO9 have been synthesized in polycrystalline form. Electron microscopy, X–ray diffraction and neutron diffraction have shown that the solid solutions are largely homogeneous and monophasic. Magnetometry and neutron diffraction have shown that the relaxor magnetisation persists in low fields when x + y = 1 but is rapidly diminished by the introduction of niobium. This change in magnetic behaviour is ascribed to the differences in the d–orbital energies of Sb5+, Nb5+ and Ta5+. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000466261100026 | Publication Date | 2019-03-02 | |
| 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 | Times cited | Open Access |
|||
| Notes | We thank EPSRC for funding through grant EP/M0189541. CMC thanks the Croucher Foundation and the University of Oxford for the award of a graduate scholarship. | Approved | no | ||
| Call Number | EMAT @ emat @c:irua:166445 | Serial | 6346 | ||
| Permanent link to this record | |||||
| 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 | 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 | ||
| Permanent link to this record | |||||
| Author | Ben Hafsia, A.; Hendrickx, M.; Batuk, M.; Khitouni, M.; Hadermann, J.; Greneche, J.-M.; Rammeh, N. | ||||
| 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. |
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| 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 | 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 | ||
| Permanent link to this record | |||||
| Author | Abeysinghe, D.; Smith, M.D.; Yeon, J.; Tran, T.T.; Sena, R.P.; Hadermann, J.; Halasyamani, P.S.; zur Loye, H.-C. | ||||
| Title | Crystal growth and structure analysis of Ce-18-W-10-O-57 : a complex oxide containing tungsten in an unusual trigonal prismatic coordination environment | Type | A1 Journal article | ||
| Year | 2017 | Publication | Inorganic chemistry | Abbreviated Journal | Inorg Chem |
| Volume | 56 | Issue | 5 | Pages | 2566-2575 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | The noncentrosymmetric tungstate oxide, Ce18W10O57) was synthesized for the first time as high-quality single crystals via the molten chloride flux method and structurally characterized by single-crystal X-ray diffraction. The compound is a structural analogue to the previously reported La18W10O57, which crystallizes in the hexagonal space group P (6) over bar 2c. The +3 oxidation state of cerium in Ce18W10O57 was achieved via the in situ reduction of Ce(IV) to Ce(III) using Zn metal. The structure consists of both isolated and face-shared WO6 octahedra and, surprisingly, isolated WO6 trigonal prisms. A careful analysis of the packing arrangement in the structure makes it possible to explain the unusual structural architecture of Ce18W10O57, which is described in detail. The temperature-dependent magnetic susceptibility of Ce18W10O57 indicates that the cerium(III) f(1) cations do not order magnetically and exhibit simple paramagnetic behavior. The SHG efficiency of Ln(18)W(10)O(57) (Ln = La, Ce) was measured as a function of particle size, and both compounds were found to be SHG active with efficiency approximately equal to that of alpha-SiO2. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Easton, Pa | Editor | ||
| Language | Wos | 000395847300026 | Publication Date | 2017-02-15 | |
| 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 | 9 | Open Access |
Not_Open_Access |
| Notes | ; Financial support for this work was provided by the National Science Foundation under DMR-1301757 and is gratefully acknowledged. T.T.T. and P.S.H. thank the Welch Foundation (Grant E-1457) and NSF-DMR-1503573. ; | Approved | Most recent IF: 4.857 | ||
| Call Number | UA @ lucian @ c:irua:142449 | Serial | 4643 | ||
| Permanent link to this record | |||||
| Author | Hunter, E.C.; Battle, P.D.; Sena, R.P.; Hadermann, J. | ||||
| Title | Ferrimagnetism as a consequence of cation ordering in the perovskite LaSr2Cr2SbO9 | Type | A1 Journal article | ||
| Year | 2017 | Publication | Journal of solid state chemistry | Abbreviated Journal | J Solid State Chem |
| Volume | 248 | Issue | Pages | 96-103 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | A polycrystalline sample of LaSr2Cr2SbO9 has been synthesised using a standard ceramic method and characterized by x-ray and neutron diffraction, magnetometry and electron microscopy. The perovskite-related compound crystallises in the triclinic space group I1 with unit cell parameters of a=5.5344(6) angstrom, b=5.5562(5) angstrom, c=7.8292(7) angstrom, a=89.986(12)degrees, beta=90.350(5)degrees and gamma=89.926(9)degrees at room temperature. The two crystallographically-distinct, six-coordinate cation sites are occupied by Cr3+ and Sb5+ in ratios of 0.868(2):0.132(2) and 0.462(2):0.538(2). Ac and de magnetometry revealed that LaSr2Cr2SbO9 is ferrimagnetic below 150 K with a magnetisation of similar to 1.25 mu(B) per formula unit in 50 kOe at 5 K. Neutron diffraction showed that the cations on the two sites order in a G-type arrangement with a mean Cr3+ moment of 2.17(1) mu(B) at 5 K, consistent with a magnetisation of 1.32 mu(B) per formula unit. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | London | Editor | ||
| Language | Wos | 000396386300012 | Publication Date | 2017-01-31 | |
| 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 | 14 | Open Access |
Not_Open_Access |
| Notes | ; Experiments at the ISIS Pulsed Neutron and Muon Source were supported by the STFC. We are grateful to I. da Silva for the assistance provided at ISIS and to the EPSRC for financial support under Grant EP/M018954/1. We also thank Diamond Light Source Ltd (EE13284) for the award of beamtime. ; | Approved | Most recent IF: 2.299 | ||
| Call Number | UA @ lucian @ c:irua:142413 | Serial | 4657 | ||
| Permanent link to this record | |||||
| Author | Zhang, F.; Chevalier, J.; Olagnon, C.; Batuk, M.; Hadermann, J.; Van Meerbeek, B.; Vleugels, J. | ||||
| 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 | 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 | ||
| Permanent link to this record | |||||
| Author | Vladimirova, S.A.; Rumyantseva, M.N.; Filatova, D.G.; Chizhov, A.S.; Khmelevsky, N.O.; Konstantinova, E.A.; Kozlovsky, V.F.; Marchevsky, A.V.; Karakulina, O.M.; Hadermann, J.; Gaskov, A.M. | ||||
| Title | Cobalt location in p -CoO x / n -SnO 2 nanocomposites: Correlation with gas sensor performances | Type | A1 Journal Article | ||
| Year | 2017 | Publication | Journal Of Alloys And Compounds | Abbreviated Journal | J Alloy Compd |
| Volume | 721 | Issue | Pages | 249-260 | |
| Keywords | A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; | ||||
| Abstract | Nanocomposites CoOx/SnO2 based on tin oxide powders with different crystallinity have been prepared by wet chemical synthesis and characterized in detail by ICP-MS, XPS, EPR, XRD, HAADF-STEM imaging and EDX-STEM mapping. It was shown that cobalt is distributed differently between the bulk and surface of SnO2 nanocrystals, which depends on the crystallinity of the SnO2 matrix. The measurements of gas sensor properties have been carried out during exposure to CO (10 ppm), and H2S (2 ppm) in dry air. The decrease of sensor signal toward CO was attributed to high catalytic activity of Co3O4 leading to oxidation of carbon monoxide entirely on the surface of catalyst particles. The formation of a p-CoOx/n-SnO2 heterojunction results in high sensitivity of nanocomposites in H2S detection. The conductance significantly changed in the presence of H2S, which was attributed to the formation of metallic cobalt sulfide and removal of the p – n junction. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000405252400030 | Publication Date | 2017-06-02 | |
| 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 | 3.133 | Times cited | Open Access |
Not_Open_Access | |
| Notes | This work was supported by ERA-Net.Plus grant N 096 FONSENS. EPR experiments were performed using the facilities of the Collective Use Center at the Moscow State University. | Approved | Most recent IF: 3.133 | ||
| Call Number | EMAT @ emat @ | Serial | 4711 | ||
| Permanent link to this record | |||||
| Author | Singh, V.; Mehta, B.R.; Sengar, S.K.; Karakulina, O.M.; Hadermann, J.; Kaushal, A. | ||||
| Title | Achieving independent control of core diameter and carbon shell thickness in Pd-C core–shell nanoparticles by gas phase synthesis | Type | A1 Journal article | ||
| Year | 2017 | Publication | Nanotechnology | Abbreviated Journal | Nanotechnology |
| Volume | 28 | Issue | 29 | Pages | 295603 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Pd-C core–shell nanoparticles with independently controllable core size and shell thickness are grown by gas phase synthesis. First, the core size is selected by electrical mobility values of charged particles, and second, the shell thickness is controlled by the concentration of carbon precursor gas. The carbon shell grows by adsorption of carbon precursor gas molecules on the surface of nanoparticles, followed by sintering. The presence of a carbon shell on Pd nanoparticles is potentially important in hydrogen-related applications operating at high temperatures or in catalytic reactions in acidic/aqueous environments. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000404633200002 | Publication Date | 2017-06-28 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0957-4484 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.44 | Times cited | 1 | Open Access |
Not_Open_Access |
| Notes | VS is thankful to the All India Council for Technical Education, India, for providing assistantship under its Quality Improvement Programme. BRM gratefully acknowledges the support of the Nanomission Programme of the Department of Science and Technology (DST), India and Schlumberger Chair Professorship. BRM would also like to acknowledge the support from the project funded by BRNS, DAE, India. | Approved | Most recent IF: 3.44 | ||
| Call Number | EMAT @ emat @c:irua:144831 | Serial | 4712 | ||
| Permanent link to this record | |||||
| Author | Morozov, V.A.; Batuk, D.; Batuk, M.; Basovich, O.M.; Khaikina, E.G.; Deyneko, D.V.; Lazoryak, B.I.; Leonidov, I.I.; Abakumov, A.M.; Hadermann, J. | ||||
| Title | Luminescence Property Upgrading via the Structure and Cation Changing in AgxEu(2–x)/3WO4and AgxGd(2–x)/3–0.3Eu0.3WO4 | Type | A1 Journal article | ||
| Year | 2017 | Publication | Chemistry of materials | Abbreviated Journal | Chem Mater |
| Volume | 29 | Issue | 20 | Pages | 8811-8823 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | The creation and ordering of A-cation vacancies and the effect of cation substitutions in the scheelite-type framework are investigated as a factor for controlling the scheelite-type structure and luminescence properties. AgxEu3+(2−x)/3□(1−2x)/3WO4 and AgxGd(2−x)/3−0.3Eu3+0.3□(1−2x)/3WO4 (x = 0.5−0) scheelite-type phases were synthesized by a solid state method, and their structures were investigated using a combination of transmission electron microscopy techniques and powder synchrotron X-ray diffraction. Transmission electron microscopy also revealed the (3 + 1)D incommensurately modulated character of AgxEu3+(2−x)/3□(1−2x)/3WO4 (x = 0.286, 0.2) phases. The crystal structures of the scheelite-based AgxEu3+(2−x)/3□(1−2x)/3WO4 (x = 0.5, 0.286, 0.2) red phosphors have been refined from high resolution synchrotron powder X-ray diffraction data. The luminescence properties of all phases under near-ultraviolet (n-UV) light have been investigated. The excitation spectra of AgxEu3+(2−x)/3□(1−2x)/3WO4 (x = 0.5, 0.286,0.2) phosphors show the strongest absorption at 395 nm, which matches well with the commercially available n-UV-emitting GaN-based LED chip. The excitation spectra of the Eu2/3□1/3WO4 and Gd0.367Eu0.30□1/3WO4 phases exhibit the highest contribution of the charge transfer band at 250 nm and thus the most efficient energy transfer mechanism between the host and the luminescent ion as compared to direct excitation. The emission spectra of all samples indicate an intense red emission due to the 5D0 → 7F2 transition of Eu3+. Concentration dependence of the 5D0 → 7F2 emission for AgxEu(2−x)/3□(1−2x)/3WO4 samples differs from the same dependence for the earlier studied NaxEu3+(2−x)/3□(1−2x)/3MoO4 (0 ≤ x ≤ 0.5) phases. The intensity of the 5D0 → 7F2 emission is reduced almost 7 times with decreasing x from 0.5 to 0, but it practically does not change in the range from x = 0.286 to x = 0.200. The emission spectra of Gd-containing samples show a completely different trend as compared to only Eu-containing samples. The Eu3+ emission under excitation of Eu3+(5L6) level (λex = 395 nm) increases more than 2.5 times with the increasing Gd3+ concentration from 0.2 (x = 0.5) to 0.3 (x = 0.2) in the AgxGd(2−x)/3−0.3Eu3+0.3□(1−2x)/3WO4, after which it remains almost constant for higher Gd3+ concentrations. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000413884900028 | Publication Date | 2017-10-24 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0897-4756 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 9.466 | Times cited | 7 | Open Access |
Not_Open_Access |
| Notes | This research was supported by FWO (project G039211N), Flanders Research Foundation. V.A.M. is grateful for financial support of the Russian Foundation for Basic Research (Grant 15-03-07741). E.G.K. and O.M.B. are grateful for financial support of the Russian Foundation for Basic Research (Grants 13-03-01020 and 16-03-00510). D.V.D. is grateful for financial support of the Russian Foundation for Basic Research (Grant 16-33-00197) and the Foundation of the President of the Russian Federation (Grant MK-7926.2016.5.). We are grateful to the ESRF for granting the beamtime. Experimental support of Andy Fitch at the ID31 beamline of ESRF is kindly acknowledged. | Approved | Most recent IF: 9.466 | ||
| Call Number | EMAT @ emat @c:irua:147241 | Serial | 4768 | ||
| Permanent link to this record | |||||
| Author | Vishwakarma, M.; Karakulina, O.M.; Abakumov, A.M.; Hadermann, J.; Mehta, B.R. | ||||
| Title | Nanoscale Characterization of Growth of Secondary Phases in Off-Stoichiometric CZTS Thin Films | Type | A1 Journal article | ||
| Year | 2018 | Publication | Journal of nanoscience and nanotechnology | Abbreviated Journal | J Nanosci Nanotechno |
| Volume | 18 | Issue | 3 | Pages | 1688-1695 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | The presence of secondary phases is one of the main issues that hinder the growth of pure kesterite Cu2ZnSnS4 (CZTS) based thin films with suitable electronic and junction properties for efficient solar cell devices. In this work, CZTS thin films with varied Zn and Sn content have been prepared by RF-power controlled co-sputtering deposition using Cu, ZnS and SnS targets and a subsequent sulphurization step. Detailed TEM investigations show that the film shows a layered structure with the majority of the top layer being the kesterite phase. Depending on the initial thin film composition, either about ~1 μm Cu-rich and Zn-poor kesterite or stoichiometric CZTS is formed as top layer. X-ray diffraction, Raman spectroscopy and transmission electron microscopy reveal the presence of Cu2−x S, ZnS and SnO2 minor secondary phases in the form of nanoinclusions or nanoparticles or intermediate layers. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000426033400022 | Publication Date | 2018-03-01 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1533-4880 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 1.483 | Times cited | Open Access |
Not_Open_Access | |
| Notes | Manoj Vishwakarma acknowl- edges IIT Delhi for MHRD fellowship. Professor B. R. Mehta acknowledges the support of the Schlumberger chair professorship. Manoj Vishwakarma, Joke Hadermann and Olesia M. karakulina acknowledge support provided by InsoL-DST. Manoj Vishwakarma acknowledges sup- port provided by CSIR funded projects and the support of DST-FIST Raman facility. References | Approved | Most recent IF: 1.483 | ||
| Call Number | EMAT @ emat @c:irua:147505 | Serial | 4775 | ||
| Permanent link to this record | |||||
| Author | Chin, C.-M.; Battle, P.D.; Blundell, S.J.; Hunter, E.; Lang, F.; Hendrickx, M.; Sena, R.P.; Hadermann, J. | ||||
| Title | Comparative study of the magnetic properties of La3Ni2B'O9 for B' = Nb, Ta or Sb | Type | A1 Journal article | ||
| Year | 2018 | Publication | Journal of solid state chemistry | Abbreviated Journal | J Solid State Chem |
| Volume | 258 | Issue | 258 | Pages | 825-834 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Polycrystalline samples of La3Ni2NbO9 and La3Ni2TaO9 have been characterised by X-ray and neutron diffraction, electron microscopy, magnetometry and muon spin relaxation (mu SR); the latter technique was also applied to La3Ni2SbO9. On the length scale of a neutron diffraction experiment, the six-coordinate sites of the monoclinic perovskite structure are occupied in a 1:1 ordered manner by Ni and a random 1/3Ni/2/3B' mixture. Electron microscopy demonstrated that this 1:1 ordering is maintained over microscopic distances, although diffuse scattering indicative of short-range ordering on the mixed site was observed. No magnetic Bragg scattering was observed in neutron diffraction patterns collected from La3Ni2B'O-9 (B' = Nb or Ta) at 5 K although in each case mu SR identified the presence of static spins below 30 K. Magnetometry showed that La3Ni2NbO9 behaves as a spin glass below 29 K but significant short-range interactions are present in La3Ni2NbO9 below 85 K. The contrasting properties of these compounds are discussed in terms of their microstructure. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | London | Editor | ||
| Language | Wos | 000423650400107 | Publication Date | 2017-12-20 | |
| 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 | 2.299 | Times cited | 6 | Open Access |
Not_Open_Access |
| Notes | ; We thank EPSRC for funding through Grants EP/M0189541 and EP/N023803. CMC thanks the Croucher Foundation and Oxford University for a graduate scholarship. We are grateful E. Suard for experimental assistance at ILL. ; | Approved | Most recent IF: 2.299 | ||
| Call Number | UA @ lucian @ c:irua:149284 | Serial | 4928 | ||
| Permanent link to this record | |||||
| 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. | ||||
| 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 | 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 | ||
| Permanent link to this record | |||||
| Author | Garud, S.; Gampa, N.; Allen, T.G.; Kotipalli, R.; Flandre, D.; Batuk, M.; Hadermann, J.; Meuris, M.; Poortmans, J.; Smets, A.; Vermang, B. | ||||
| Title | Surface passivation of CIGS solar cells using gallium oxide | Type | A1 Journal article | ||
| Year | 2018 | Publication | Physica status solidi : A : applications and materials science | Abbreviated Journal | Phys Status Solidi A |
| Volume | 215 | Issue | 7 | Pages | 1700826 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | This work proposes gallium oxide grown by plasma-enhanced atomic layer deposition, as a surface passivation material at the CdS buffer interface of Cu(In,Ga)Se-2 (CIGS) solar cells. In preliminary experiments, a metal-insulator-semiconductor (MIS) structure is used to compare aluminium oxide, gallium oxide, and hafnium oxide as passivation layers at the CIGS-CdS interface. The findings suggest that gallium oxide on CIGS may show a density of positive charges and qualitatively, the least interface trap density. Subsequent solar cell results with an estimated 0.5nm passivation layer show an substantial absolute improvement of 56mV in open-circuit voltage (V-OC), 1mAcm(-2) in short-circuit current density (J(SC)), and 2.6% in overall efficiency as compared to a reference (with the reference showing 8.5% under AM 1.5G). | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000430128500015 | Publication Date | 2018-02-27 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1862-6300 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 1.775 | Times cited | 8 | Open Access |
Not_Open_Access |
| Notes | ; The work published in this paper was supported by the European Research Council (ERC) under the Union's Horizon 2020 research and innovation programme (grant agreement No 715027). The authors would also like to thank Dr. Marcel Simor (Solliance) for the CIGS layer fabrication and Prof. Johan Lauwaert (Universtiy of Ghent) for his guidance on DLTS measurements. ; | Approved | Most recent IF: 1.775 | ||
| Call Number | UA @ lucian @ c:irua:150761 | Serial | 4981 | ||
| Permanent link to this record | |||||
| Author | Kutukov, P.; Rumyantseva, M.; Krivetskiy, V.; Filatova, D.; Batuk, M.; Hadermann, J.; Khmelevsky, N.; Aksenenko, A.; Gaskov, A. | ||||
| 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. | ||||
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| 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 | 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 | ||
| Permanent link to this record | |||||
| Author | Hasanli, N.; Gauquelin, N.; Verbeeck, J.; Hadermann, J.; Hayward, M.A. | ||||
| Title | Small-moment paramagnetism and extensive twinning in the topochemically reduced phase Sr2ReLiO5.5 | Type | A1 Journal article | ||
| Year | 2018 | Publication | Journal of the Chemical Society : Dalton transactions | Abbreviated Journal | Dalton T |
| Volume | 47 | Issue | 44 | Pages | 15783-15790 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Reaction of the cation-ordered double perovskite Sr2ReLiO6 with dilute hydrogen at 475 degrees C leads to the topochemical deintercalation of oxide ions from the host lattice and the formation of a phase of composition Sr2ReLiO5.5, as confirmed by thermogravimetric and EELS data. A combination of neutron and electron diffraction data reveals the reduction process converts the -Sr2O2-ReLiO4-Sr2O2-ReLiO4- stacking sequence of the parent phase into a -Sr2O2-ReLiO3-Sr2O2-ReLiO4-, partially anion-vacant ordered sequence. Furthermore a combination of electron diffraction and imaging reveals Sr2ReLiO5.5 exhibits extensive twinning – a feature which can be attributed to the large, anisotropic volume expansion of the material on reduction. Magnetisation data reveal a strongly reduced moment of (eff) = 0.505(B) for the d(1) Re6+ centres in the phase, suggesting there remains a large orbital component to the magnetism of the rhenium centres, despite their location in low symmetry coordination environments. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000450208000019 | Publication Date | 2018-10-18 | |
| 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 | 4.029 | Times cited | Open Access |
Not_Open_Access | |
| Notes | 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). Experiments at the ISIS pulsed neutron facility were supported by a beam time allocation from the STFC. NH acknowledges funding from the “State Programme on Education of Azerbaijani Youth Abroad in 2007-2015” by the Ministry of Education of Azerbaijan. J. V. and N. G. acknowledge funding through the GOA project “Solarpaint” of the University of Antwerp. The microscope used in this work was partly funded by the Hercules Fund from the Flemish Government. | Approved | Most recent IF: 4.029 | ||
| Call Number | EMAT @ emat @c:irua:155771 | Serial | 5137 | ||
| Permanent link to this record | |||||
| Author | Morozov, V.; Deyneko, D.; Basoyich, O.; Khaikina, E.G.; Spassky, D.; Morozov, A.; Chernyshev, V.; Abakumov, A.; Hadermann, J. | ||||
| Title | Incommensurately modulated structures and luminescence properties of the AgxSm(2-x)/3WO4 (x=0.286, 0.2) scheelites as thermographic phosphors | Type | A1 Journal article | ||
| Year | 2018 | Publication | Chemistry of materials | Abbreviated Journal | Chem Mater |
| Volume | 30 | Issue | 14 | Pages | 4788-4798 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Ag+ for Sm3+ substitution in the scheelite-type AgxSm(2-x)/3 square(1-2x)/3WO4 tungstates has been investigated for its influence on the cation-vacancy ordering and luminescence properties. A solid state method was used to synthesize the x = 0.286 and x = 0.2 compounds, which exhibited (3 + 1)D incommensurately modulated structures in the transmission electron microscopy study. Their structures were refined using high resolution synchrotron powder X-ray diffraction data. Under near-ultraviolet light, both compounds show the characteristic emission lines for (4)G(5/2) -> H-6(J) (J = 5/2, 7/2, 9/2, and 11/2) transitions of the Sm3+ ions in the range 550-720 nm, with the J = 9/2 transition at the similar to 648 nm region being dominant for all photoluminescence spectra. The intensities of the (4)G(5/2) -> H-6(9/2) and (4)G(5/2) -> H-6(7/2) bands have different temperature dependencies. The emission intensity ratios (R) for these bands vary reproducibly with temperature, allowing the use of these materials as thermographic phosphors. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | American Chemical Society | Place of Publication | Washington, D.C | Editor | |
| Language | Wos | 000440105500037 | Publication Date | 2018-06-21 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0897-4756 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 9.466 | Times cited | 2 | Open Access |
Not_Open_Access |
| Notes | ; This research was supported by FWO (Project G039211N), Flanders Research Foundation. The research was carried out within the state assignment of FASO of Russia (Themes No. 0339-2016-0007). V.M. thanks the Russian Foundation for Basic Research (Grant 18-03-00611) for financial support. E.G.K. and O.B. acknowledge financial support from the Russian Foundation for Basic Research (Grant 16-03-00510). D.D. thanks the Foundation of the Russian Federation President (Grant MK-3502.2018.5) for financial support. We are grateful to the ESRF for granting the beamtime. V.C. is grateful for the financial support of the Russian Ministry of Science and Education (Project No. RFMEFI61616X0069). We are grateful to the ESRF for the access to ID22 station (experiment MA-3313). ; | Approved | Most recent IF: 9.466 | ||
| Call Number | UA @ lucian @ c:irua:153156 | Serial | 5107 | ||
| Permanent link to this record | |||||