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| Author | Neyts, E.C.; Ostrikov, K.K.; Sunkara, M.K.; Bogaerts, A. | ||||
| Title | Plasma Catalysis: Synergistic Effects at the Nanoscale | Type | A1 Journal article | ||
| Year | 2015 | Publication | Chemical reviews | Abbreviated Journal | Chem Rev |
| Volume | 115 | Issue | 115 | Pages | 13408-13446 |
| Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
| Abstract | Thermal-catalytic gas processing is integral to many current industrial processes. Ever-increasing demands on conversion and energy efficiencies are a strong driving force for the development of alternative approaches. Similarly, synthesis of several functional materials (such as nanowires and nanotubes) demands special processing conditions. Plasma catalysis provides such an alternative, where the catalytic process is complemented by the use of plasmas that activate the source gas. This combination is often observed to result in a synergy between plasma and catalyst. This Review introduces the current state-of-the-art in plasma catalysis, including numerous examples where plasma catalysis has demonstrated its benefits or shows future potential, including CO2 conversion, hydrocarbon reforming, synthesis of nanomaterials, ammonia production, and abatement of toxic waste gases. The underlying mechanisms governing these applications, as resulting from the interaction between the plasma and the catalyst, render the process highly complex, and little is known about the factors leading to the often-observed synergy. This Review critically examines the catalytic mechanisms relevant to each specific application. | ||||
| Address | Department of Chemistry, Research Group PLASMANT, Universiteit Antwerpen , Universiteitsplein 1, 2610 Wilrijk-Antwerp, Belgium | ||||
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| Language | English | Wos | 000367563000006 | Publication Date | 2015-11-30 |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
ISSN  |
0009-2665 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 47.928 | Times cited | 204 | Open Access | |
| Notes | ECN and AB gratefully acknowledge financial support from the Fund of Scientific Research Flanders (FWO), Belgium, Grant Number G.0217.14N. KO acknowledges partial support by the Australian Research Council and CSIRO’s OCE Science Leaders Program. MKS acknowledges partial support from US National Science Foundation through grants DMS 1125909 and EPSCoR 1355448 and also PhD students Babajide Ajayi, Apolo Nambo and Maria Carreon for their help. | Approved | Most recent IF: 47.928; 2015 IF: 46.568 | ||
| Call Number | c:irua:130001 | Serial | 3993 | ||
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| Author | Hoffman, B.M.; Lukoyanov, D.; Yang, Z.-Y.; Dean, D.R.; Seefeldt, L.C. | ||||
| Title | Mechanism of Nitrogen Fixation by Nitrogenase: The Next Stage | Type | A1 Journal Article | ||
| Year | 2014 | Publication | Chemical Reviews | Abbreviated Journal | Chem. Rev. |
| Volume | 114 | Issue | 8 | Pages | 4041-4062 |
| Keywords | A1 Journal Article; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ; | ||||
| Abstract | Ammonia is a crucial nutrient used for plant growth and as a building block in pharmaceutical and chemical industry, produced via nitrogen fixation of the ubiquitous atmospheric N2. Current industrial ammonia production relies heavily on fossil resources, but a lot of work is put into developing non-fossil based pathways. Among these is the use of nonequilibrium plasma. In this work, we investigated water vapor as H source for nitrogen fixation into NH3 by non-equilibrium plasma. The highest selectivity towards NH3 was observed with low amounts of added H2O vapor, but the highest production rate was reached at high H2O vapor. | ||||
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| Language | Wos | Publication Date | 2014-04-23 | ||
| Series Editor | Series Title | Abbreviated Series Title | |||
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| ISSN |
0009-2665 | ISBN | Additional Links | ||
| Impact Factor | Times cited | Open Access | |||
| Notes | We would like to thank Sylvia Dewilde (Department of Biomedical Sciences) for providing analytical equipment. | Approved | no | ||
| Call Number | PLASMANT @ plasmant @ | Serial | 6337 | ||
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| Author | Kuckova, S.; Hamidi-Asl, E.; Matulkova, I.; Hynek, R.; De Wael, K.; Sanyova, J.; Janssens, K. | ||||
| Title | Technoques and applications of Surface-Enhanced Raman Scattering Spectroscopy (SERSS) focused on cultural heritage | Type | A1 Journal article | ||
| Year | 2018 | Publication | Chemické listy | Abbreviated Journal | Chem Listy |
| Volume | 112 | Issue | 5 | Pages | 312-316 |
| Keywords | A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) | ||||
| Abstract | The review is devoted to a modern method of vibrational spectroscopy – surface enhanced Raman spectroscopy Its principle and some of its special variants (imunnoSERS and TERS (Tip-Enhanced Raman Spectroscopy)) are described m a simpinified manner Wide application possibilities are demonstrated on selected examples from its application m culturinl heritage. | ||||
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| Language | Wos | Publication Date | |||
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| Series Volume | Series Issue | Edition | |||
| ISSN |
0009-2770; 1213-7103 | ISBN | Additional Links | UA library record; WoS full record | |
| Impact Factor | 0.387 | Times cited | Open Access | ||
| Notes | ; ; | Approved | Most recent IF: 0.387 | ||
| Call Number | UA @ admin @ c:irua:151616 | Serial | 5869 | ||
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| Author | Ejsmont, A.; Andreo, J.; Lanza, A.; Galarda, A.; Macreadie, L.; Wuttke, S.; Canossa, S.; Ploetz, E.; Goscianska, J. | ||||
| Title | Applications of reticular diversity in metal-organic frameworks : an ever-evolving state of the art | Type | A1 Journal article | ||
| Year | 2021 | Publication | Coordination Chemistry Reviews | Abbreviated Journal | Coordin Chem Rev |
| Volume | 430 | Issue | Pages | 213655 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Metal-organic frameworks (MOFs) are exciting materials due to their extensive applicability in a multitude of modern technological fields. Their most prominent characteristic and primary origin of their widespread success is the exceptional variety of their structures, which we termed 'reticular diversity'. Naturally, the ever-emerging applications of MOFs made it increasingly common that researchers from various areas delve into reticular chemistry to overcome their scientific challenges. This confers a crucial role to comprehensive overviews capable of providing newcomers with the knowledge of the state of the art, as well as with the key physics and chemistry considerations needed to design MOFs for a specific application. In this review, we commit to this purpose by outlining the fundamental understanding needed to carefully navigate MOFs' reticular diversity in their main fields of application, namely hostguest chemistry, chemical sensing, electronics, photophysics, and catalysis. Such knowledge and a meticulous, open-minded approach to the design of MOFs paves the way for their most innovative and successful applications, and for the global advancement of the research areas they are employed in. (C) 2020 Elsevier B.V. All rights reserved. | ||||
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| Language | Wos | 000615299000008 | Publication Date | 2020-12-13 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN |
0010-8545 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 13.324 | Times cited | Open Access | OpenAccess | |
| Notes | Approved | Most recent IF: 13.324 | |||
| Call Number | UA @ admin @ c:irua:176731 | Serial | 6715 | ||
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| Author | Thirumalraj, alamurugan; Palanisamy, S.; Chen, S.-M.; De Wael, K. | ||||
| Title | A graphene/gelatin composite material for the entrapment of hemoglobin for bioelectrochemical sensing applications | Type | A1 Journal article | ||
| Year | 2016 | Publication | Journal of the electrochemical society | Abbreviated Journal | J Electrochem Soc |
| Volume | 163 | Issue | 7 | Pages | 265-271 |
| Keywords | A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) | ||||
| Abstract | In the present work, a novel graphene (GN) and gelatin (GTN) composite was prepared and used as an immobilization matrix for hemoglobin (Hb). Compared with Hb immobilized on a bare, GN or GTN modified glassy carbon electrode (GCE), a stable and pair of well-defined quasi redox couple was observed at an Hb modified GN/GTN composite GCE at a formal potential of −0.306 V versus Ag|AgCl. The direct electrochemical behavior of Hb was greatly enhanced by the presence of both GTN and GN. A heterogeneous electron transfer rate constant (Ks) was calculated as 3.82 s−1 for Hb immobilized at GN/GTN modified GCE, which indicates the fast direct electron transfer of Hb toward the electrode surface. The biosensor shows a stable and wide linear response for H2O2 in the linear response range from 0.1 μM to 786.6 μM with an analytical sensitivity and limit of detection of 0.48 μAμM−1 cm−2 and 0.04 μM, respectively. The fabricated biosensor holds its high selectivity in the presence of potentially active interfering species and metal ions. The biosensor shows its satisfactory practical ability in the commercial contact lens solution and human serum samples. | ||||
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| Language | Wos | 000377412900047 | Publication Date | 2016-04-08 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN |
0013-4651 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.259 | Times cited | 9 | Open Access | |
| Notes | ; This project was supported by the Ministry of Science and Technology (project no. NSC1012113M027001MY3), Taiwan (Republic of China). The authors express their sincere thanks to Prof. Bih-Show Lou, Chemistry Division, Center for General Education, Chang Gung University, Tao-Yuan, Taiwan for providing the human serum samples. ; | Approved | Most recent IF: 3.259 | ||
| Call Number | UA @ admin @ c:irua:132627 | Serial | 5635 | ||
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| Author | de Gryse, O.; Clauws, P.; Vanhellemont, J.; Lebedev, O.I.; van Landuyt, J.; Simoen, E.; Claeys, C. | ||||
| Title | Characterization of oxide precipitates in heavily B-doped silicon by infrared spectroscopy | Type | A1 Journal article | ||
| Year | 2004 | Publication | Journal of the electrochemical society | Abbreviated Journal | J Electrochem Soc |
| Volume | 151 | Issue | 9 | Pages | G598-G605 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Infrared absorption spectra of oxygen precipitates in boron-doped silicon with a boron concentration between 10(17) and 10(19) cm(-3) are analyzed, applying the spectral function representation of composite materials. The aspect ratio of the platelet precipitates is determined by transmission electron microscopy measurements. The analysis shows that in samples with moderate doping levels (<10(18) B cm(-3)) SiOγ precipitates are formed with the same composition as in the lightly doped case. In the heavily boron-doped (>10(18) cm(-3)) samples, however, the measured spectra of the precipitates are consistent with a mixture of SiO2 and B2O3, with a volume fraction of B2O3 as high as 0.41 in the most heavily doped case. (C) 2004 The Electrochemical Society. | ||||
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| Publisher | Place of Publication | New York, N.Y. | Editor | ||
| Language | Wos | 000223622000072 | Publication Date | 2004-08-30 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN |
0013-4651; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.259 | Times cited | 13 | Open Access | |
| Notes | Fwo; Iuap P5/01 | Approved | Most recent IF: 3.259; 2004 IF: 2.356 | ||
| Call Number | UA @ lucian @ c:irua:103760 | Serial | 330 | ||
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| Author | de Witte, H.; de Gendt, S.; Douglas, M.; Conard, T.; Kenis, K.; Mertens, P.W.; Vandervorst, W.; Gijbels, R. | ||||
| Title | Evaluation of time-of-flight secondary ion mass spectrometry for metal contamination monitoring on wafer surfaces | Type | A1 Journal article | ||
| Year | 2000 | Publication | Journal of the electrochemical society | Abbreviated Journal | J Electrochem Soc |
| Volume | 147 | Issue | 5 | Pages | 13-17 |
| Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
| Abstract | |||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | New York, N.Y. | Editor | ||
| Language | Wos | 000087075200052 | Publication Date | 2002-07-28 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN |
0013-4651; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.259 | Times cited | 14 | Open Access | |
| Notes | Approved | Most recent IF: 3.259; 2000 IF: 2.293 | |||
| Call Number | UA @ lucian @ c:irua:34073 | Serial | 1089 | ||
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| Author | Verbeeck, J.; Lebedev, O.I.; Van Tendeloo, G.; Cagnon, L.; Bougerol, C.; Tourillon, T. | ||||
| Title | Fe and Co nanowires and nanotubes synthesized by template electrodeposition: a HRTEM and EELS study | Type | A1 Journal article | ||
| Year | 2003 | Publication | Journal of the electrochemical society | Abbreviated Journal | J Electrochem Soc |
| Volume | 150 | Issue | 10 | Pages | E468-E471 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Co and Fe nanowires and/or nanotubes are electrochemically synthesized through nanoporous membranes. By combining high-resolution transmission electron microscopy (HRTEM), electron energy loss spectroscopy (EELS), and energy filtered TEM techniques, their structural and crystallographic characteristics are precisely determined. The synthesis was shown to produce cigar-shaped single monocrystalline Co and Fe nanowires with a diameter of about 60 nm. All wires were surrounded by an epitaxial oxide layer (Co3O4 or Fe3O4) of roughly 10 nm. The Fe nanotubes were built up of Fe3O4 nanocrystals. Electron diffraction showed that all nanocrystals had a common crystallographic axis, creating a pseudomonocrystalline wall in the nanotubes. (C) 2003 The Electrochemical Society. | ||||
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| Publisher | Place of Publication | New York, N.Y. | Editor | ||
| Language | Wos | 000185639800039 | Publication Date | 2003-09-12 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
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| ISSN |
0013-4651; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.259 | Times cited | 41 | Open Access | |
| Notes | Approved | Most recent IF: 3.259; 2003 IF: 2.361 | |||
| Call Number | UA @ lucian @ c:irua:54858UA @ admin @ c:irua:54858 | Serial | 1176 | ||
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| Author | Stuer, C.; van Landuyt, J.; Bender, H.; de Wolf, I.; Rooyackers, R.; Badenes, G. | ||||
| Title | Investigation by convergent beam electron diffraction of the stress around shallow trench isolation structures | Type | A1 Journal article | ||
| Year | 2001 | Publication | Journal of the electrochemical society | Abbreviated Journal | J Electrochem Soc |
| Volume | 148 | Issue | 11 | Pages | G597-G601 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Convergent beam electron diffraction (CBED) is used in this study to investigate the stress distribution around shallow trench isolation (STI) structures. Attention is given to the influence of the different processing parameters and the width and spacing of the structures. The use of a wet or a dry pregate oxidation is found to have a strong influence on the stress behavior. Isolated lines show more stress, leading to the formation of defects in the silicon substrate if a wet pregate oxidation is used. The CBED analyses are compared with micro-Raman and bright-field transmission electron microscopy measurements. (C) 2001 The Electrochemical Society. | ||||
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| Publisher | Place of Publication | New York, N.Y. | Editor | ||
| Language | Wos | 000171653100038 | Publication Date | 2002-07-26 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN |
0013-4651; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.259 | Times cited | 13 | Open Access | |
| Notes | Approved | Most recent IF: 3.259; 2001 IF: 2.033 | |||
| Call Number | UA @ lucian @ c:irua:103394 | Serial | 1725 | ||
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| Author | Vassiliev, S.Y.; Laurinavichute, V.K.; Abakumov, A.M.; Govorov, V.A.; Bendovskii, E.B.; Turner, S.; Filatov, A.Y.; Tarasovskii, V.P.; Borzenko, A.G.; Alekseeva, A.M.; Antipov, E.V. | ||||
| Title | Microstructural aspects of the degradation behavior of SnO2-based anodes for aluminum electrolysis | Type | A1 Journal article | ||
| Year | 2010 | Publication | Journal of the electrochemical society | Abbreviated Journal | J Electrochem Soc |
| Volume | 157 | Issue | 5 | Pages | C178-C186 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | The performance of SnO2 ceramic anodes doped with copper and antimony oxides was examined in cryolite alumina melts under anodic polarization at different cryolite ratios, temperatures, times, and current densities. The corroded part consists of a narrow strong corrosion zone at the anode surface with damage of the intergrain contacts and a large increase in porosity, a wider moderate corrosion zone with a smaller porosity increase, and a Cu depletion zone, where the ceramic retains its initial microstructure and a slight porosity increase occurs due to the removal of the Cu-rich inclusions. Mechanical destruction of the anode was never observed in the 10100 h tests. A microstructural model of the ceramic was suggested, consisting of grains with an Sb-doped SnO2 grain core surrounded by an ~200 to 500 nm grain shell where SnO2 was simultaneously doped with Sb and Mn+ (M=Cu2+,Fe3+,Al3+). The grains were separated by a few nanometers thick Cu-enriched grain boundaries. Different secondary charge carrier (holes) concentrations and electric conductivities in the grain core and grain shell result in a higher current density at the intergrain regions that leads to their profound degradation, especially in the low temperature acidic melt. | ||||
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| Publisher | Place of Publication | New York, N.Y. | Editor | ||
| Language | Wos | 000276555300037 | Publication Date | 2010-04-12 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN |
0013-4651; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.259 | Times cited | 3 | Open Access | |
| Notes | Approved | Most recent IF: 3.259; 2010 IF: 2.427 | |||
| Call Number | UA @ lucian @ c:irua:82260 | Serial | 2040 | ||
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| Author | McCalla, E.; Prakash, A.S.; Berg, E.; Saubanere, M.; Abakumov, A.M.; Foix, D.; Klobes, B.; Sougrati, M.T.; Rousse, G.; Lepoivre, F.; Mariyappan, S.; Doublet, M.L.; Gonbeau, D.; Novak, P.; Van Tendeloo, G.; Hermann, R.P.; Tarascon, J.M.; | ||||
| Title | Reversible Li-intercalation through oxygen reactivity in Li-rich Li-Fe-Te oxide materials | Type | A1 Journal article | ||
| Year | 2015 | Publication | Journal of the electrochemical society | Abbreviated Journal | J Electrochem Soc |
| Volume | 162 | Issue | 162 | Pages | A1341-A1351 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Lithium-rich oxides are a promising class of positive electrode materials for next generation lithium-ion batteries, and oxygen plays a prominent role during electrochemical cycling either by forming peroxo-like species and/or by irreversibly forming oxygen gas during first charge. Here, we present Li-Fe-Te-O materials which show a tremendous amount of oxygen gas release. This oxygen release accounts for nearly all the capacity during the first charge and results in vacancies as seen by transmission electron microscopy. There is no oxidation of either metal during charge but significant changes in their environments. These changes are particularly extreme for tellurium. XRD and neutron powder diffraction both show limited Changes during cycling and no appreciable change in lattice parameters. A density functional theory study of this material is performed and demonstrates that the holes created on some of the oxygen atoms upon oxidation are partially stabilized through the formation of shorter O-O bonds, i.e. (O-2)(n-) species which on further delithiation show a spontaneous O-2 de-coordination from the cationic network and migration to the now empty lithium layer. The rate limiting step during charge is undoubtedly the diffusion of oxygen either out along the lithium layer or via columns of oxygen atoms. (C) 2015 The Electrochemical Society. All rights reserved. | ||||
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| Publisher | Place of Publication | New York, N.Y. | Editor | ||
| Language | Wos | 000355643700030 | Publication Date | 2015-04-29 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
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| ISSN |
0013-4651;1945-7111; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.259 | Times cited | 23 | Open Access | |
| Notes | Approved | Most recent IF: 3.259; 2015 IF: 3.266 | |||
| Call Number | c:irua:126445 | Serial | 2903 | ||
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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 | |
| 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 | Retuerto, M.; Skiadopoulou, S.; Li, M.R.; Abakumov, A.M.; Croft, M.; Ignatov, A.; Sarkar, T.; Abbett, B.M.; Pokorný, J.; Savinov, M.; Nuzhnyy, D.; Prokleška, J.; Abeykoon, M.; Stephens, P.W.; Hodges, J.P.; Vaněk, P.; Fennie, C.J.; Rabe, K.M.; Kamba, S.; Greenblatt, M.; | ||||
| Title | Pb2MnTeO6 double perovskite : an antipolar anti-ferromagnet | Type | A1 Journal article | ||
| Year | 2016 | Publication | Inorganic chemistry | Abbreviated Journal | Inorg Chem |
| Volume | 55 | Issue | 55 | Pages | 4320-4329 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Pb2MnTeO6, a new double perovskite, was synthesized. Its crystal structure was determined by synchrotron X-ray and powder neutron diffraction. Pb2MnTeO6 is monoclinic (I2/m) at room temperature with a regular arrangement of all the cations in their polyhedra. However, when the temperature is lowered to similar to 120 K it undergoes a phase transition from I2/m to C2/c structure. This transition is accompanied by a displacement of the Pb atoms from the center of their polyhedra due to the 6s2 lone-pair electrons, together with a surprising off-centering of Mn2+ (d5) magnetic cations. This strong first-order phase transition is also evidenced by specific heat, dielectric, Raman, and infrared spectroscopy measurements. The magnetic characterizations indicate an anti-ferromagnetic (AFM) order below TN approximate to 20 K; analysis of powder neutron diffraction data confirms the magnetic structure with propagation vector k = (0 1 0) and collinear AFM spins. The observed jump in dielectric permittivity near similar to 150 K implies possible anti-ferroelectric behavior; however, the absence of switching suggests that Pb2MnTeO6 can only be antipolar. First-principle calculations confirmed that the crystal and magnetic structures determined are locally stable and that anti-ferroelectric switching is unlikely to be observed in Pb2MnTeO6. | ||||
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| Publisher | Place of Publication | Easton, Pa | Editor | ||
| Language | Wos | 000375519700027 | Publication Date | 2016-04-08 | |
| 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 | |
| Notes | Approved | Most recent IF: 4.857 | |||
| Call Number | UA @ lucian @ c:irua:134219 | Serial | 4258 | ||
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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. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000380181400035 | Publication Date | 2016-07-18 | |
| 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 | 12 | Open Access | |
| 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 | ||
| Permanent link to this record | |||||
| 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 | ||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | English | Wos | 000385785700085 | Publication Date | 2016-10-05 |
| 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 | 6 | Open Access | |
| 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 | Li, M.-R.; Deng, Z.; Lapidus, S.H.; Stephens, P.W.; Segre, C.U.; Croft, M.; Sena, R.P.; Hadermann, J.; Walker, D.; Greenblatt, M. | ||||
| Title | Ba-3(Cr0.97(1)Te0.03(1))(2)TeO9: in Search of Jahn-Teller Distorted Cr(II) Oxide | Type | A1 Journal article | ||
| Year | 2016 | Publication | Inorganic chemistry | Abbreviated Journal | Inorg Chem |
| Volume | 55 | Issue | 55 | Pages | 10135-10142 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | A novel 6H-type hexagonal perovskite Ba-3(Cr0.97(1)Te0.03(1))(2)TeO9 was prepared at high pressure (6 GPa) and temperature (1773 K). Both transmission electron microscopy and synchrotron powder X-ray diffraction data demonstrate that Ba-3(Cr0.97(1)Te0.03(1))(2)TeO9 crystallizes in P6(3)/mmc with face-shared (Cr0.97(1)Te0.03(1))O-6 octahedral pairs interconnected with TeO6 octahedra via corner-sharing. Structure analysis shows a mixed Cr2+/Cr3+ valence state with similar to 10% Cr2+. The existence of Cr2+ in Ba-3(Cr0.10(1)2+Cr0.87(1)3+Te0.036+)(2)TeO9 is further evidenced by X-ray absorption near-edge spectroscopy. Magnetic properties measurements show a paramagnetic response down to 4 K and a small glassy-state curvature at low temperature. In this work, the octahedral Cr2+O6 component is stabilized in an oxide material for the first time; the expected Jahn-Teller distortion of high-spin (d(4)) Cr2+ is not found, which is attributed to the small proportion of Cr2+ (similar to 10%) and the face-sharing arrangement of CrO6 octahedral pairs, which structurally disfavor axial distortion. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Easton, Pa | Editor | ||
| Language | Wos | 000385785700026 | Publication Date | 2016-09-28 | |
| 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 | 2 | Open Access | |
| Notes | Approved | Most recent IF: 4.857 | |||
| Call Number | UA @ lucian @ c:irua:140313 | Serial | 4440 | ||
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| Author | Tunca, B.; Lapauw, T.; Karakulina, O.M.; Batuk, M.; Cabioc’h, T.; Hadermann, J.; Delville, R.; Lambrinou, K.; Vleugels, J. | ||||
| Title | Synthesis of MAX Phases in the Zr-Ti-Al-C System | Type | A1 Journal article | ||
| Year | 2017 | Publication | Inorganic chemistry | Abbreviated Journal | Inorg Chem |
| Volume | 56 | Issue | 56 | Pages | 3489-3498 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | This study reports on the synthesis and characterization of MAX phases in the (Zr,Ti)n+1AlCn system. The MAX phases were synthesized by reactive hot pressing and pressureless sintering in the 1350–1700 °C temperature range. The produced ceramics contained large fractions of 211 and 312 (n = 1, 2) MAX phases, while strong evidence of a 413 (n = 3) stacking was found. Moreover, (Zr,Ti)C, ZrAl2, ZrAl3, and Zr2Al3 were present as secondary phases. In general, the lattice parameters of the hexagonal 211 and 312 phases followed Vegard’s law over the complete Zr-Ti solid solution range, but the 312 phase showed a non-negligible deviation from Vegard’s law around the (Zr0.33,Ti0.67)3Al1.2C1.6 stoichiometry. High-resolution scanning transmission electron microscopy combined with X-ray diffraction demonstrated ordering of the Zr and Ti atoms in the 312 phase, whereby Zr atoms occupied preferentially the central position in the close-packed M6X octahedral layers. The same ordering was also observed in 413 stackings present within the 312 phase. The decomposition of the secondary (Zr,Ti)C phase was attributed to the miscibility gap in the ZrC-TiC system. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000397171100045 | Publication Date | 2017-03-20 | |
| 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 | 26 | Open Access | OpenAccess |
| Notes | Fonds Wetenschappelijk Onderzoek, G.0431.10N.F ; Agentschap voor Innovatie door Wetenschap en Technologie, 131081 ; European Atomic Energy Community, 604862 ; SCK-CEN Academy for Nuclear Science and Technology; Hercules Foundation, Project/Award no: AKUL/1319 Project/Award no: ZW09-09 ; | Approved | Most recent IF: 4.857 | ||
| Call Number | EMAT @ emat @ c:irua:141794 | Serial | 4491 | ||
| 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. | ||||
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| 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 | ||
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| 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 | ||
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| Author | Lander, L.; Rousse, G.; Batuk, D.; Colin, C.V.; Dalla Corte, D.A.; Tarascon, J.-M. | ||||
| Title | Synthesis, structure, and electrochemical properties of k-based sulfates K2M2(SO4)3) with M = Fe and Cu | Type | A1 Journal article | ||
| Year | 2017 | Publication | Inorganic chemistry | Abbreviated Journal | Inorg Chem |
| Volume | 56 | Issue | 4 | Pages | 2013-2021 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Stabilizing new host structures through potassium extraction from K-based polyanionic materials has been proven to be an interesting approach to develop new Li+/Na+ insertion materials. Pursuing the same trend, we here report the feasibility of preparing langbeinite “Fe-2(SO4)(3)” via electrochemical and chemical oxidation of K2Fe2(SO4)(3). Additionally, we succeeded in stabilizing a new K2Cu2(SO4)(3) phase via a solid-state synthesis approach. This novel compound crystallizes in a complex orthorhombic structure that differs from that of langbeinite as deduced from synchrotron X-ray and neutron powder diffraction. Electrochemically, the performance of this new phase is limited, which we explain in terms of sluggish diffusion kinetics. We further show that K2Cu2(SO4)(3) decomposes into K2Cu3O(SO4)(3) on heating, and we report for the first time the synthesis of fedotovite K2Cu3O(SO4)(3). Finally, the fundamental attractiveness of these S = 1/2 systems for physicists is examined by neutron magnetic diffraction, which reveals the absence of a long-range ordering of Cu2+ magnetic moments down to 1.5 K. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Easton, Pa | Editor | ||
| Language | Wos | 000394736600027 | Publication Date | 2017-01-27 | |
| 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 | 4.857 | Times cited | 13 | Open Access | Not_Open_Access |
| Notes | ; We thank Matthieu Courty for performing TGA/DSC measurements. Use of the 11-BM mail service of the APS at Argonne National Laboratory was supported by the U.S. Department of Energy under Contract DE-AC02-06CH11357 and is acknowledged. The French CRG D1B is acknowledged for allocating neutron beamtime. L.L. thanks the ANR “Hipolite” for the Ph.D. funding. ; | Approved | Most recent IF: 4.857 | ||
| Call Number | UA @ lucian @ c:irua:142531 | Serial | 4692 | ||
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| Author | Weber, D.; Huber, M.; Gorelik, T.E.; Abakumov, A.M.; Becker, N.; Niehaus, O.; Schwickert, C.; Culver, S.P.; Boysen, H.; Senyshyn, A.; Poettgen, R.; Dronskowski, R.; Ressler, T.; Kolb, U.; Lerch, M. | ||||
| Title | Molybdenum oxide nitrides of the Mo2(O,N,\square)5 type : on the way to Mo2O5 | Type | A1 Journal article | ||
| Year | 2017 | Publication | Inorganic chemistry | Abbreviated Journal | Inorg Chem |
| Volume | 56 | Issue | 15 | Pages | 8782-8792 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Blue-colored molybdenum oxide nitrides of the Mo-2(O,N,square)(5) type were synthesized by direct nitridation of commercially available molybdenum trioxide with a mixture of gaseous ammonia and oxygen. Chemical composition, crystal structure, and stability of the obtained and hitherto unknown compounds are studied extensively. The average oxidation state of +5 for molybdenum is proven by Mo K near-edge X-ray absorption spectroscopy; the magnetic behavior is in agreement with compounds exhibiting (MoO6)-O-v units. The new materials are stable up to similar to 773 K in an inert gas atmosphere. At higher temperatures, decomposition is observed. X-ray and neutron powder diffraction, electron diffraction, and high-resolution transmission electron microscopy reveal the structure to be related to VNb9O24.9-type phases, however, with severe disorder hampering full structure determination. Still, the results demonstrate the possibility of a future synthesis of the potential binary oxide Mo2O5. On the basis of these findings, a tentative suggestion on the crystal structure of the potential compound Mo2O5, backed by electronic-structure and phonon calculations from first principles, is given. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Easton, Pa | Editor | ||
| Language | Wos | 000407405500026 | Publication Date | 2017-07-17 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN |
0020-1669 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 4.857 | Times cited | 3 | Open Access | Not_Open_Access |
| Notes | ; Financial support from the Deutsche Forschungsgemeinschaft (SPP 1415, LE 781/ 11-1, DR 342/22-2) is gratefully acknowledged. The authors are grateful to J. Barthel, Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons Julich, Germany, for STEM image simulations. This work was further supported by Diamond Light Source (beamtime awards EE13560) within beamtime proposal SP13560. The Hamburg Synchrotron Radiation Laboratory, HASYLAB, and the FRM II, Garching, are acknowledged for providing beamtime. ; | Approved | Most recent IF: 4.857 | ||
| Call Number | UA @ lucian @ c:irua:145727 | Serial | 4744 | ||
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| Author | Barreca, D.; Gri, F.; Gasparotto, A.; Altantzis, T.; Gombac, V.; Fornasiero, P.; Maccato, C. | ||||
| Title | Insights into the Plasma-Assisted Fabrication and Nanoscopic Investigation of Tailored MnO2Nanomaterials | Type | A1 Journal Article | ||
| Year | 2018 | Publication | Inorganic Chemistry | Abbreviated Journal | Inorg Chem |
| Volume | 57 | Issue | 23 | Pages | 14564-14573 |
| Keywords | A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; | ||||
| Abstract | Among transition metal oxides, MnO2 is of considerable importance for various technological end-uses,from heterogeneous catalysis to gas sensing, owing to its structural flexibility and unique properties at the nanoscale. In this work, we demonstrate the successful fabrication of supported MnO2 nanomaterials by a catalyst-free, plasmaassisted process starting from a fluorinated manganese(II) molecular source in Ar/O2 plasmas. A thorough multitechnique characterization aimed at the systematic investigation of material structure, chemical composition, and morphology revealed the formation of F-doped, oxygendeficient, MnO2-based nanomaterials, with a fluorine content tunable as a function of growth temperature (TG). Whereas phase-pure β-MnO2 was obtained for 100 °C ≤ TG ≤ 300 °C, the formation of mixed phase MnO2 + Mn2O3 nanosystems took place at 400 °C. In addition, the system nano-organization could be finely tailored, resulting in a controllable evolution from wheat-ear columnar arrays to high aspect ratio pointed-tip nanorod assemblies. Concomitantly, magnetic force microscopy analyses suggested the formation of spin domains with features dependent on material morphology. Preliminary tests in Vislight activated photocatalytic degradation of rhodamine B aqueous solutions pave the way to possible applications of the target materials in wastewater purification. |
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000452344400016 | Publication Date | 2018-12-03 | |
| 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 | Open Access | Not_Open_Access | |
| Notes | The present work was financially supported by Padova University DOR 2016−2018 and P-DiSC #03BIRD2016- UNIPD projects. T.A. acknowledges a postdoctoral grant from the Research Foundation Flanders (FWO). Thanks are also due to Prof. Sara Bals (EMAT, University of Antwerp, Belgium) and to Dr. Giorgio Carraro (Department of Chemical Sciences, Padova University, Italy) for valuable support and experimental assistance. | Approved | Most recent IF: 4.857 | ||
| Call Number | EMAT @ emat @c:irua:156245 | Serial | 5147 | ||
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| Author | Tang, Y.; Hunter, E.C.; Battle, P.D.; Hendrickx, M.; Hadermann, J.; Cadogan, J.M. | ||||
| Title | Ferrimagnetism as a consequence of unusual cation ordering in the Perovskite SrLa2FeCoSbO9 | Type | A1 Journal article | ||
| Year | 2018 | Publication | Inorganic chemistry | Abbreviated Journal | Inorg Chem |
| Volume | 57 | Issue | 12 | Pages | 7438-7445 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | A polycrystalline sample of SrLa2FeCoSbO9 has been prepared in a solid-state reaction and studied by a combination of electron microscopy, magnetometry, Mossbauer spectroscopy, X-ray diffraction, and neutron diffraction. The compound adopts a monoclinic (space group P2(1)/n; a = 5.6218(6), b = 5.6221(6), c = 7.9440(8) angstrom, beta = 90.050(7)degrees at 300 K) perovskite-like crystal structure with two crystallographically distinct six-coordinate sites. One of these sites is occupied by 2/3 Co-2(+),1/3 Fe3+ and the other by 2/3 Sb5+, 1/3 Fe3+. This pattern of cation ordering results in a transition to a ferrimagnetic phase at 215 K. The magnetic moments on nearest-neighbor, six-coordinate cations align in an antiparallel manner, and the presence of diamagnetic Sb5+ on only one of the two sites results in a nonzero remanent magnetization of similar to 1 mu(B) per formula unit at 5 K. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Easton, Pa | Editor | ||
| Language | Wos | 000436023800073 | Publication Date | 2018-05-29 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN |
0020-1669 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 4.857 | Times cited | 6 | Open Access | Not_Open_Access |
| Notes | ; PDB, ECH, and JH acknowledge support from EPSRC under grant EP/M0189954/1. We would like to thank the STFC for the award of beamtime at the ISIS Neutron and Muon Source (RB 1610100), and we thank Dr. I. da Silva for the assistance provided. We also thank Dr. R Paria Sena for help with the HAADF-STEM and STEM-EDX experiments. ; | Approved | Most recent IF: 4.857 | ||
| Call Number | UA @ lucian @ c:irua:152485 | Serial | 5103 | ||
| Permanent link to this record | |||||
| Author | Cassidy, S.J.; Orlandi, F.; Manuel, P.; Hadermann, J.; Scrimshire, A.; Bingham, P.A.; Clarke, S.J. | ||||
| Title | Complex Magnetic Ordering in the Oxide Selenide Sr2Fe3Se2O3 | Type | A1 Journal article | ||
| Year | 2018 | Publication | Inorganic chemistry | Abbreviated Journal | Inorg Chem |
| Volume | 57 | Issue | 16 | Pages | 10312-10322 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Easton, Pa | Editor | ||
| Language | Wos | 000442489100078 | Publication Date | 2018-07-31 | |
| 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 | 2 | Open Access | OpenAccess |
| Notes | ; S. J. Cassidy prepared the samples and performed the diffraction and magnetometry measurements. F.O., P.M., and S. J. Cassidy measured and interpreted the NPD data. J.H. performed and interpreted the electron diffraction measurements. A.S. and P.A.B. performed and interpreted the Mossbauer spectroscopy measurements. S. J. Cassidy and S. J. Clarke conceived the project and wrote the paper with input from all co-authors. We acknowledge the financial support of the EPSRC (Grants EP/I017844/1, EP/P018874/1, and EP/ M020517/1), and the Leverhulme Trust (RPG-2014-221). We thank the ESTEEM2 network for enabling the electron microscopy investigations, the ISIS facility for the award of beamtime on WISH (RB1610357), and the Diamond Light Source Ltd. for the award of beam time on I11 (allocation EE13284). We thank Dr. C. Murray, Dr. S. Day and Dr. A. Baker for assistance on I11 and Dr. M. Coduri and Dr. A. N. Fitch for assistance on ID22. ; | Approved | Most recent IF: 4.857 | ||
| Call Number | UA @ lucian @ c:irua:153723 | Serial | 5085 | ||
| Permanent link to this record | |||||
| Author | Cassidy, S.J.; Pitcher, M.J.; Lim, J.J.K.; Hadermann, J.; Allen, J.P.; Watson, G.W.; Britto, S.; Chong, E.J.; Free, D.G.; Grey, C.P.; Clarke, S.J. | ||||
| Title | Layered CeSO and LiCeSO oxide chalcogenides obtained via topotactic oxidative and reductive transformations | Type | A1 Journal article | ||
| Year | 2019 | Publication | Inorganic chemistry | Abbreviated Journal | Inorg Chem |
| Volume | 58 | Issue | 6 | Pages | 3838-3850 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | The chemical accessibility of the Celv oxidation state enables redox chemistry to be performed on the naturally coinagemetal -deficient phases CeM1-xSO (M = Cu, Ag). A metastable black compound with the PbFC1 structure type (space group P4/nmm: a = 3.8396(1) angstrom, c = 6.607(4) angstrom, V = 97.40(6) angstrom(3)) and a composition approaching CeSO is obtained by deintercalation of Ag from CeAg0.8SO. High-resolution transmission electron microscopy reveals the presence of large defect-free regions in CeSO, but stacking faults are also evident which can be incorporated into a quantitative model to account for the severe peak anisotropy evident in all the highresolution X-ray and neutron diffractograms of bulk CeSO samples; these suggest that a few percent of residual Ag remains. A strawcolored compound with the filled PbFCI (i.e., ZrSiCuAs- or HfCuSi2type) structure (space group P4/nmm: a = 3.98171(1) angstrom, c = 8.70913(5) angstrom, V = 138.075(1) angstrom 3) and a composition close to LiCeSO, but with small amounts of residual Ag, is obtained by direct reductive lithiation of CeAga8S0 or by insertion of Li into CeSO using chemical or electrochemical means. Computation of the band structure of pure, stoichiometric CeSO predicts it to be a Ce' compound with the 4f-states lying approximately 1 eV above the sulfide-dominated valence band maximum. Accordingly, the effective magnetic moment per Ce ion measured in the CeSO samples is much reduced from the value found for the Ce3+-containing LiCeSO, and the residual paramagnetism corresponds to the Ce3+ ions remaining due to the presence of residual Ag, which presumably reflects the difficulty of stabilizing Ce' in the presence of sulfide (S2-). Comparison of the behavior of CeCu0.8SO with that of CeCu0.8SO reveals much slower reaction kinetics associated with the Cu,_xS layers, and this enables intermediate CeCui LixSO phases to be isolated. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000461978700036 | Publication Date | 2019-02-25 | |
| 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 | Open Access | OpenAccess | |
| Notes | ; We thank the UK EPSRC (EP/M020517/1 and EP/P018874/1), the Leverhulme Trust (RPG-2014-221), and Science Foundation Ireland (Grant 12/IA/1414) for funding and the EPSRC for additional studentship support. We acknowledge the ISIS pulsed neutron and muon source and the Diamond Light Source Ltd. (EE13284 and EE18786) and the ESRF for the award of beam time. We thank Dr. R I. Smith for assistance on the neutron beamlines, Dr. A. Baker and Dr. C. Murray for support on III, and Dr. C. Curls for support on ID31. ; | Approved | Most recent IF: 4.857 | ||
| Call Number | UA @ admin @ c:irua:159426 | Serial | 5253 | ||
| Permanent link to this record | |||||
| Author | Tunca, B.; Lapauw, T.; Delville, R.; Neuville, D.R.; Hennet, L.; Thiaudiere, D.; Ouisse, T.; Hadermann, J.; Vleugels, J.; Lambrinou, K. | ||||
| Title | Synthesis and Characterization of Double Solid Solution (Zr,Ti)(2)(Al,Sn)C MAX Phase Ceramics | Type | A1 Journal article | ||
| Year | 2019 | Publication | Inorganic chemistry | Abbreviated Journal | Inorg Chem |
| Volume | 58 | Issue | 10 | Pages | 6669-6683 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Quasi phase-pure (>98 wt %) MAX phase solid solution ceramics with the (ZryTi)(2)(Al-0.5,Sn-0.5)C stoichiometry and variable Zr/Ti ratios were synthesized by both reactive hot pressing and pressureless sintering of ZrH2, TiH2, Al, Sn, and C powder mixtures. The influence of the different processing parameters, such as applied pressure and sintering atmosphere, on phase purity and microstructure of the produced ceramics was investigated. The addition of Sn to the (Zr,Ti)(2)AlC system was the key to achieve phase purity. Its effect on the crystal structure of a 211-type MAX phase was assessed by calculating the distortions of the octahedral M6C and trigonal M(6)A prisms due to steric effects. The M(6)A prismatic distortion values were found to be smaller in Sn-containing double solid solutions than in the (Zr,Ti)(2)AlC MAX phases. The coefficients of thermal expansion along the < a > and < c > directions were measured by means of Rietveld refinement of high-temperature synchrotron X-ray diffraction data of (Zr1-x,Ti-x)(2)(Al-0.5,Sn-0.5)C MAX phase solid solutions with x = 0, 0.3, 0.7, and 1. The thermal expansion coefficient data of the Ti-2(Al-0.5,Sn-0.5)C solid solution were compared with those of the Ti2AlC and Ti2SnC ternary compounds. The thermal expansion anisotropy increased in the (Zr,Ti)(2)(Al-0.5,Sn-0.5)C double solid solution MAX phases as compared to the Zr-2(Al-0.5,Sn-0.5)C and Ti-2(Al-0.5,Sn-0.5)C end-members. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000469304700014 | Publication Date | 2019-05-01 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN |
0020-1669 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 4.857 | Times cited | 3 | Open Access | Not_Open_Access |
| Notes | ; H. Roussel and D. Pinek are acknowledged for the Ti<INF>2</INF>SnC single-crystal production and high-temperature XRD measurements performed at Grenoble INP-LMGP-CMTC. This research was funded partly by the European Atomic Energy Community's (Euratom) Seventh Framework Programme FP7/2007-2013 under Grant Agreement No. 604862 (FP7MatISSE), and partly by the Euratom research and training programme 2014-2018 under Grant Agreement No. 740415 (H2020 IL TROVATORE). T.L. thanks the Agency for Innovation by Science and Technology (IWT), Flanders, Belgium, for Ph.D. Grant No. 131081. B.T. acknowledges the financial support of the SCK.CEN Academy for Nuclear Science and Technology. All authors gratefully acknowledge Synchrotron SOLEIL for the allocated time at the DIFFABS beamline in association with Project 20161410 entitled “Investigation of (Zr-Ti)-Al-C MAX phases with in-situ high-temperature XRD” and the Hercules Foundation for Project AKUL/1319 (CombiS(T)EM). ; | Approved | Most recent IF: 4.857 | ||
| Call Number | UA @ admin @ c:irua:160318 | Serial | 5261 | ||
| 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. | ||||
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| 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 | Xu, X.; Jones, M.A.; Cassidy, S.J.; Manuel, P.; Orlandi, F.; Batuk, M.; Hadermann, J.; Clarke, S.J. | ||||
| 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 | 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 | ||
| Permanent link to this record | |||||
| Author | Skaggs, C.M.; Kang, C.-J.; Perez, C.J.; Hadermann, J.; Emge, T.J.; Frank, C.E.; Pak, C.; Lapidus, S.H.; Walker, D.; Kotliar, G.; Kauzlarich, S.M.; Tan, X.; Greenblatt, M. | ||||
| Title | Ambient and high pressure CuNiSb₂ : metal-ordered and metal-disordered NiAs-type derivative pnictides | Type | A1 Journal article | ||
| Year | 2020 | Publication | Inorganic Chemistry | Abbreviated Journal | Inorg Chem |
| Volume | 59 | Issue | 19 | Pages | 14058-14069 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | The mineral Zlatogorite, CuNiSb2, was synthesized in the laboratory for the first time by annealing elements at ambient pressure (CuNiSb2-AP). Rietveld refinement of synchrotron powder X-ray diffraction data indicates that CuNiSb2-AP crystallizes in the NiAs-derived structure (P (3) over bar m1, #164) with Cu and Ni ordering. The structure consists of alternate NiSb6 and CuSb6 octahedral layers via face-sharing. The formation of such structure instead of metal disordered NiAs-type structure (P6(3)/mmc, #194) is validated by the lower energy of the ordered phase by first-principle calculations. Interatomic crystal orbital Hamilton population, electron localization function, and charge density analysis reveal strong Ni-Sb, Cu-Sb, and Cu-Ni bonding and long weak Sb-Sb interactions in CuNiSb2-AP. The magnetic measurement indicates that CuNiSb2-AP is Pauli paramagnetic. First-principle calculations and experimental electrical resistivity measurements reveal that CuNiSb2-AP is a metal. The low Seebeck coefficient and large thermal conductivity suggest that CuNiSb2 is not a potential thermoelectric material. Single crystals were grown by chemical vapor transport. The high pressure sample (CuNiSb2-8 GPa) was prepared by pressing CuNiSb2-AP at 700 degrees C and 8 GPa. However, the structures of single crystal and CuNiSb2-8 GPa are best fit with a disordered metal structure in the P (3) over bar m1 space group, corroborated by transmission electron microscopy. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000580381700028 | Publication Date | 2020-09-20 | |
| 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 | 4.6 | Times cited | Open Access | OpenAccess | |
| Notes | Approved | Most recent IF: 4.6; 2020 IF: 4.857 | |||
| Call Number | UA @ admin @ c:irua:174331 | Serial | 6714 | ||
| Permanent link to this record | |||||
| Author | Leinders, G.; Baldinozzi, G.; Ritter, C.; Saniz, R.; Arts, I.; Lamoen, D.; Verwerft, M. | ||||
| Title | Charge Localization and Magnetic Correlations in the Refined Structure of U3O7 | Type | A1 Journal article | ||
| Year | 2021 | Publication | Inorganic Chemistry | Abbreviated Journal | Inorg Chem |
| Volume | 60 | Issue | 14 | Pages | 10550-10564 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Atomic arrangements in the mixed-valence oxide U3O7 are refined from high-resolution neutron scattering data. The crystallographic model describes a long-range structural order in a U60O140 primitive cell (space group P42/n) containing distorted cuboctahedral oxygen clusters. By combining experimental data and electronic structure calculations accounting for spin–orbit interactions, we provide robust evidence of an interplay between charge localization and the magnetic moments carried by the uranium atoms. The calculations predict U3O7 to be a semiconducting solid with a band gap of close to 0.32 eV, and a more pronounced charge-transfer insulator behavior as compared to the well-known Mott insulator UO2. Most uranium ions (56 out of 60) occur in 9-fold and 10-fold coordinated environments, surrounding the oxygen clusters, and have a tetravalent (24 out of 60) or pentavalent (32 out of 60) state. The remaining uranium ions (4 out of 60) are not contiguous to the oxygen cuboctahedra and have a very compact, 8-fold coordinated environment with two short (2 × 1.93(3) Å) “oxo-type” bonds. The higher Hirshfeld charge and the diamagnetic character point to a hexavalent state for these four uranium ions. Hence, the valence state distribution corresponds to 24/60 × U(IV) + 32/60 U(V) + 4/60 U(VI). The tetravalent and pentavalent uranium ions are predicted to carry noncollinear magnetic moments (with amplitudes of 1.6 and 0.8 μB, respectively), resulting in canted ferromagnetic order in characteristic layers within the overall fluorite-related structure. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000675430900049 | Publication Date | 2021-07-19 | |
| 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 | Open Access | OpenAccess | |
| Notes | Financial support for this research was partly provided by the Energy Transition Fund of the Belgian FPS Economy (Project SF-CORMOD – Spent Fuel CORrosion MODeling). This work was performed in part using HPC resources from GENCI-IDRIS (Grants 2020-101450 and 2020-101601), and in part 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. GL thanks E. Suard and C. Schreinemachers for assistance during the neutron scattering experiments at the ILL. GB acknowledges V. Petříček for suggestions on using JANA2006. | Approved | Most recent IF: 4.857 | ||
| Call Number | EMAT @ emat @c:irua:179907 | Serial | 6801 | ||
| Permanent link to this record | |||||