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Author | Krishnamurthy, S.C.; Arseenko, M.; Kashiwar, A.; Dufour, P.; Marchal, Y.; Delahaye, J.; Idrissi, H.; Pardoen, T.; Mertens, A.; Simar, A. | ||||
Title | Controlled precipitation in a new Al-Mg-Sc alloy for enhanced corrosion behavior while maintaining the mechanical performance | Type | A1 Journal article | ||
Year | 2023 | Publication | Materials characterization | Abbreviated Journal | |
Volume | 200 | Issue | Pages | 112886-11 | |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | The hot working of 5xxx series alloys with Mg ≥3.5 wt% is a concern due to the precipitation of β (Al3Mg2) phase at grain boundaries favoring Inter Granular Corrosion (IGC). The mechanical and corrosion properties of a new 5028-H116 Al-Mg-Sc alloy under various β precipitates distribution is analyzed by imposing different cooling rates from the hot forming temperature (i.e. 325 °C). The mechanical properties are maintained regardless of the heat treatment. However, the different nucleation sites and volume fractions of β precipitates for different cooling rates critically affect IGC. Controlled furnace cooling after the 325 °C heat treatment is ideal in 5028-H116 alloy to reduce susceptibility to IGC after sensitization. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000977059100001 | Publication Date | 2023-04-03 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1044-5803 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.7 | Times cited | Open Access | OpenAccess | |
Notes | Approved | Most recent IF: 4.7; 2023 IF: 2.714 | |||
Call Number | UA @ admin @ c:irua:195598 | Serial | 7291 | ||
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Author | Yang, T.; Kong, Y.; Li, K.; Lu, Q.; Wang, Y.; Du, Y.; Schryvers, D. | ||||
Title | Quasicrystalline clusters transformed from C14-MgZn₂ nanoprecipitates in Al alloys | Type | A1 Journal article | ||
Year | 2023 | Publication | Materials characterization | Abbreviated Journal | |
Volume | 199 | Issue | Pages | 112772-112777 | |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Ultrafine faulty C14-MgZn2 Laves phase precipitates containing quasicrystalline clusters and demonstrating the formation of binary quasicrystalline precipitates with Penrose-like random-tiling were observed in the over-aged FCC matrix of a commercial 7N01 Al-Zn-Mg alloy, using high angle annular dark field scanning transmission electron microscopy. The evolution from C14-Laves phase to quasicrystalline clusters is illustrated, and five-fold symmetry can be found in both real and reciprocal spaces. Our findings reveal the possibility of quasicrystalline formation from Laves phase in a highly plastic metal matrix like Al and demonstrate the structural relationship between Laves phase and quasicrystals. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000954788800001 | Publication Date | 2023-03-02 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1044-5803 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.7 | Times cited | Open Access | Not_Open_Access | |
Notes | Approved | Most recent IF: 4.7; 2023 IF: 2.714 | |||
Call Number | UA @ admin @ c:irua:196106 | Serial | 8446 | ||
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Author | Andersen, Ja.; van 't Veer, K.; Christensen, Jm.; Østberg, M.; Bogaerts, A.; Jensen, Ad. | ||||
Title | Ammonia decomposition in a dielectric barrier discharge plasma: Insights from experiments and kinetic modeling | Type | A1 Journal article | ||
Year | 2023 | Publication | Chemical engineering science | Abbreviated Journal | |
Volume | 271 | Issue | Pages | 118550 | |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Utilizing ammonia as a storage medium for hydrogen is currently receiving increased attention. A possible method to retrieve the hydrogen is by plasma-catalytic decomposition. In this work, we combined an experimental study, using a dielectric barrier discharge plasma reactor, with a plasma kinetic model, to get insights into the decomposition mechanism. The experimental results revealed a similar effect on the ammonia conversion when changing the flow rate and power, where increasing the specific energy input (higher power or lower flow rate) gave an increased conversion. A conversion as high as 82 % was achieved at a specific energy input of 18 kJ/Nl. Furthermore, when changing the discharge volume from 31 to 10 cm3, a change in the plasma distribution factor from 0.2 to 0.1 was needed in the model to best describe the conversions of the experiments. This means that a smaller plasma volume caused a higher transfer of energy through micro-discharges (non-uniform plasma), which was found to promote the decomposition of ammonia. These results indicate that it is the collisions between NH3 and the high-energy electrons that initiate the decomposition. Moreover, the rate of ammonia destruction was found by the model to be in the order of 1022 molecules/(cm3 s) during the micro-discharges, which is 5 to 6 orders of magnitude higher than in the afterglows. A considerable re-formation of ammonia was found to take place in the afterglows, limiting the overall conversion. In addition, the model revealed that implementation of packing material in the plasma introduced high concentrations of surface-bound hydrogen atoms, which introduced an additional ammonia re-formation pathway through an Eley-Rideal reaction with gas phase NH2. Furthermore, a more uniform plasma is predicted in the presence of MgAl2O4, which leads to a lower average electron energy during micro-discharges and a lower conversion (37 %) at a comparable residence time for the plasma alone (51 %). | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000946293200001 | Publication Date | 2023-02-09 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0009-2509 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.7 | Times cited | Open Access | OpenAccess | |
Notes | We thank Topsoe A/S for providing the packing material used, the research group PLASMANT (UAntwerpen) for sharing their plasma kinetic model and allowing us to perform the calculations on their clusters, and the Department of Chemical and Biochemical Engineering, Technical University of Denmark, for funding this project. | Approved | Most recent IF: 4.7; 2023 IF: 2.895 | ||
Call Number | PLASMANT @ plasmant @c:irua:195204 | Serial | 7237 | ||
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Author | Wang, Y.; Yuan, Y.; Liao, X.; Van Tendeloo, G.; Zhao, Y.; Sun, C. | ||||
Title | Chip-based in situ TEM investigation of structural thermal instability in aged layered cathode | Type | A1 Journal article | ||
Year | 2023 | Publication | Nanoscale Advances | Abbreviated Journal | |
Volume | 5 | Issue | 16 | Pages | 4182-4190 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Thermally induced oxygen release is an intrinsic structural instability in layered cathodes, which causes thermal runaway issues and becomes increasingly critical with the continuous improvement in energy density. Furthermore, thermal runaway events always occur in electrochemically aged cathodes, where the coupling of the thermal and electrochemical effect remains elusive. Herein, we report the anomalous segregation of cobalt metal in an aged LiCoO2 cathode, which is attributed to the local exposure of the high-energy (100) surface of LiCoO2 and weak interface Co-O dangling bonds significantly promoting the diffusion of Co. The presence of the LCO-Co interface severely aggregated the oxygen release in the form of dramatic Co growth. A unique particle-to-particle oxygen release pathway was also found, starting from the isolated high reduction areas induced by the cycling heterogeneity. This study provides atomistic insight into the robust coupling between the intrinsic structural instability and electrochemical cycling. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 001030149900001 | Publication Date | 2023-07-14 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2516-0230 | ISBN | Additional Links | UA library record; WoS full record | |
Impact Factor | 4.7 | Times cited | Open Access | OpenAccess | |
Notes | Approved | Most recent IF: 4.7; 2023 IF: NA | |||
Call Number | UA @ admin @ c:irua:198281 | Serial | 8841 | ||
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Author | Meng, S.; Li, S.; Sun, S.; Bogaerts, A.; Liu, Y.; Yi, Y. | ||||
Title | NH3 decomposition for H2 production by thermal and plasma catalysis using bimetallic catalysts | Type | A1 Journal article | ||
Year | 2024 | Publication | Chemical engineering science | Abbreviated Journal | Chemical Engineering Science |
Volume | 283 | Issue | Pages | 119449 | |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Plasma catalysis has emerged as a promising approach for driving thermodynamically unfavorable chemical reactions. Nevertheless, comprehending the mechanisms involved remains a challenge, leading to uncertainty about whether the optimal catalyst in plasma catalysis aligns with that in thermal catalysis. In this research, we explore this question by studying monometallic catalysts (Fe, Co, Ni and Mo) and bimetallic catalysts (Fe-Co, Mo- Co, Fe-Ni and Mo-Ni) in both thermal catalytic and plasma catalytic NH3 decomposition. Our findings reveal that the Fe-Co bimetallic catalyst exhibits the highest activity in thermal catalysis, the Fe-Ni bimetallic catalyst outperforms others in plasma catalysis, indicating a discrepancy between the optimal catalysts for the two catalytic modes in NH3 decomposition. Comprehensive catalyst characterization, kinetic analysis, temperature program surface reaction experiments and plasma diagnosis are employed to discuss the key factors influencing NH3 decomposition performance. |
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Publisher | Place of Publication | Editor | |||
Language | Wos | 001105312500001 | Publication Date | 2023-10-28 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0009-2509 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.7 | Times cited | Open Access | Not_Open_Access | |
Notes | Universiteit Antwerpen, 32249 ; National Natural Science Foundation of China, 21503032 ; PetroChina Innovation Foundation, 2018D-5007-0501 ; | Approved | Most recent IF: 4.7; 2024 IF: 2.895 | ||
Call Number | PLASMANT @ plasmant @c:irua:201009 | Serial | 8967 | ||
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Author | Gestels, A.; Van der Snickt, G.; Caen, J.; Nuyts, G.; Legrand, S.; Vanmeert, F.; Detry, F.; Janssens, K.; Steenackers, G. | ||||
Title | Combined MA-XRF, MA-XRPD and SEM-EDX analysis of a medieval stained-glass panel formerly from Notre Dame, Paris reveals its material history | Type | A1 Journal article | ||
Year | 2022 | Publication | Microchemical journal | Abbreviated Journal | Microchem J |
Volume | 177 | Issue | Pages | 107304 | |
Keywords | A1 Journal article; Engineering sciences. Technology; Art; Antwerp Cultural Heritage Sciences (ARCHES); Antwerp X-ray Imaging and Spectroscopy (AXIS) | ||||
Abstract | As part of its conservation-restoration, the 13th century stained-glass panel ‘the Annunciation’, was examined at the micro- and macro level. This window, since 1898 in the collection of the Museum Mayer Van den Bergh (Antwerp, B), was formerly a part of the southern Rose window of the Notre Dame Cathedral (Paris, F). The insigths emerging from a first phase of the analysis, comprising non-invasive analysis techniques such as optical microscopy combined with macroscopic X-ray fluorescence (MA-XRF) and X-ray diffraction (MA-XRPD) mapping, were used to select sampling positions for the second phase of investigation that involved micro-invasive analysis, namely scanning-electron microscopy coupled to energy-dispersive X-ray analysis (SEM-EDX). The aim of the investigation was fourfold: (1) to assess the applicability of MA-XRF scanning for the characterisation of stained glass windows prior to any conservation or restoration procedure, (2) to assess the applicability of MA-XRPD scanning to identify the degradation products formed on the surface of stained glass windows, (3) to establish a method to limit the set of sampled glass fragments taken from a glass panel for quantititive analysis while maintaining sufficient representativeness and (4) to distinguish the original glass panes and grisaille paint from non-original glass panes that were inserted during various past interventions. Most of the panes in this window proved to consist of medieval potash glass, consistent with the 13th c. origin of the window while a limited number of panes were identified as non-original infills, with divergent glass compositional types and/or colorants. Most panes derive their color from the pot metal glass (i.e. homogenously colored) they were made of. Some of the panes that originally had a red flashed layer on their surface, completely or partially lost this layer due to weathering. Three main compositional glass families with similar color could be defined. With the exception of the yellow and orange panes, the chromophoric elements responsible for the dark(er) and light(er) blue (Co), green (Cu), purple (Mn) and red colors (Cu) were identified. Two different grisaille paints were encountered, part of which were restored during the 19th century. On the basis of this information, all missing pieces were replaced by glass panes with appropriate colors and the panel could be successfully conserved to its former glory. On the surface of several panes, typical glass degradation products such as calcite, syngenite and gypsum were identified, together with lead based degradation products such as anglesite and palmierite. In addition, the presence of hematite and melanotekite in the grisailles was observed; also the presence of Zn, uncorrelated to Cu, in the grissailes on the right side of the window became apparent. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000850000900001 | Publication Date | 2022-02-22 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0026-265x; 0026-265x | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.8 | Times cited | Open Access | OpenAccess | |
Notes | Approved | Most recent IF: 4.8 | |||
Call Number | UA @ admin @ c:irua:187493 | Serial | 7138 | ||
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Author | Fabri, C.; Moretti, M.; Van Passel, S. | ||||
Title | On the (ir)relevance of heatwaves in climate change impacts on European agriculture | Type | A1 Journal article | ||
Year | 2022 | Publication | Climatic Change | Abbreviated Journal | Climatic Change |
Volume | 174 | Issue | 1-2 | Pages | 16-20 |
Keywords | A1 Journal article; Engineering Management (ENM) | ||||
Abstract | The Ricardian model is a widely used approach based on cross-sectional regression analysis to estimate climate change impacts on agricultural productivity. Up until now, researchers have focused on the impacts of gradual changes in temperature and precipitation, even though climate change is known to encompass also changes in the severity and frequency of extreme weather events. This research investigates the impact of heatwaves on European agriculture, additional to the impact of average climate change. Using a dataset of more than 60,000 European farms, the study examines whether adding a measure for heatwaves to the Ricardian model influences its results. We find that heatwaves have a minor impact on agricultural productivity and that this impact is moderated by average temperature. In colder regions, farm productivity increases with the number of heatwave days. For warmer regions, land values decrease with heatwave frequency. Despite the moderating effect, the marginal effect of heatwave frequency, i.e. the percentage change in agricultural land values caused by one more heatwave day per year, is small in comparison to the effect of average temperature increases. Non-marginal effects are found to be relevant, but only in the case of increased heatwave frequency. According to our results, farms are not expected to suffer more from extreme weather than from mean climate change, as was claimed by several previous studies. | ||||
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Language | Wos | 000861873100002 | Publication Date | 2022-09-29 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0165-0009; 1573-1480 | ISBN | Additional Links | UA library record; WoS full record | |
Impact Factor | 4.8 | Times cited | Open Access | OpenAccess | |
Notes | Approved | Most recent IF: 4.8 | |||
Call Number | UA @ admin @ c:irua:191483 | Serial | 7364 | ||
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Author | Saqlain, M.A.; Hussain, A.; Siddiq, D.M.; Leenaerts, O.; Leitão, A.A. | ||||
Title | DFT Study of Synergistic Catalysis of the Water-Gas-Shift Reaction on Cu-Au Bimetallic Surfaces | Type | A1 Journal article | ||
Year | 2016 | Publication | ChemCatChem | Abbreviated Journal | Chemcatchem |
Volume | 8 | Issue | 8 | Pages | 1208-1217 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | The water-gas-shift reaction (WGSR) is an important industrial process that can be significantly enhanced at suitable catalyst surfaces. In this work, we investigate the catalytic behavior of metallic Cu(1 0 0) and bimetallic Cu–Au(1 0 0) surfaces. With density functional theory calculations, the variation in the Gibbs free energy (ΔG°), the activation barriers, and the rate constants for the WGSR are calculated. The variation in ΔG° for water dissociation shows that the process is spontaneous up to 520 K on the bimetallic surface and up to 229 K on the Cu(1 0 0) surface. The calculated rate constants for the process also show that the bimetallic surface is much more reactive than the Cu(1 0 0) surface. The calculated pressure–temperature phase diagram for water dissociation shows that the partial pressure of H2O required for water dissociation on the bimetallic surface is substantially lower than that on the Cu(1 0 0) surface at all the studied temperatures. Additionally, the calculations demonstrate that the kinetics of the water-gas-shift reaction is dominated by redox processes on both the surfaces. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000373074900026 | Publication Date | 2016-02-26 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1867-3880 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.803 | Times cited | 8 | Open Access | |
Notes | ; The authors would like to thank the Brazilian agencies CNPq, CAPES, FAPEMIG (CEX-PPM-00262/13), and TWAS for financial support and CENAPAD-SP for computational facilities. M.A. Saqlain pays special thanks to all the members of GFQSI for making his stay in Brazil memorable. ; | Approved | Most recent IF: 4.803 | ||
Call Number | c:irua:133236 | Serial | 4070 | ||
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Author | Zhong, R.; Peng, L.; de Clippel, F.; Gommes, C.; Goderis, B.; Ke, X.; Van Tendeloo, G.; Jacobs, P.A.; Sels, B.F. | ||||
Title | An eco-friendly soft template synthesis of mesostructured silica-carbon nanocomposites for acid catalysis | Type | A1 Journal article | ||
Year | 2015 | Publication | ChemCatChem | Abbreviated Journal | Chemcatchem |
Volume | 7 | Issue | 7 | Pages | 3047-3058 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | The synthesis of ordered mesoporous silica-carbon composites was explored by employing TEOS and sucrose as the silica and carbon precursor respectively, and the triblock copolymer F127 as a structure-directing agent via an evaporation-induced self-assembly (EISA) process. It is demonstrated that the synthesis procedures allow for control of the textural properties and final composition of these silica-carbon nanocomposites via adjustment of the effective SiO2/C weight ratio. Characterization by SAXS, N-2 physisorption, HRTEM, TGA, and C-13 and Si-29 solid-state MAS NMR show a 2D hexagonal mesostructure with uniform large pore size ranging from 5.2 to 7.6nm, comprising of separate carbon phases in a continuous silica phase. Ordered mesoporous silica and non-ordered porous carbon can be obtained by combustion of the pyrolyzed nanocomposites in air or etching with HF solution, respectively. Sulfonic acid groups can be readily introduced to such kind of silica-carbon nanocomposites by a standard sulfonation procedure with concentrated sulfuric acid. Excellent acid-catalytic activities and selectivities for the dimerization of styrene to produce 1,3-diphenyl-1-butene and dimerization of -methylstyrene to unsaturated dimers were demonstrated with the sulfonated materials. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000361189400037 | Publication Date | 2015-09-03 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1867-3880; 1867-3899 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.803 | Times cited | 13 | Open Access | |
Notes | Approved | Most recent IF: 4.803; 2015 IF: 4.556 | |||
Call Number | UA @ lucian @ c:irua:127836 | Serial | 4138 | ||
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Author | Lu, A.K.A.; Houssa, M.; Luisier, M.; Pourtois, G. | ||||
Title | Impact of layer alignment on the behavior of MoS2-ZrS2 tunnel field-effect transistors : an ab initio study | Type | A1 Journal article | ||
Year | 2017 | Publication | Physical review applied | Abbreviated Journal | Phys Rev Appl |
Volume | 8 | Issue | 3 | Pages | 034017 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Tunnel field-effect transistors based on van der Waals heterostructures are emerging device concepts for low-power applications, auguring sub-60 mV/dec subthreshold swing values. In these devices, the channel is built from a stack of several different two-dimensional materials whose nature allows tailoring the band alignments and enables a good electrostatic control of the device. In this work, we propose a theoretical study of the variability of the performances of a MoS2-ZrS2 tunnel field-effect transistor induced by fluctuations of the relative position or the orientation of the layers. Our results indicate that although a steep subthreshold slope (20 mV/dec) is achievable, fluctuations in the relative orientation of the ZrS2 layer with respect to the MoS2 one lead to a significant variability in the tunneling current by about one decade. This arises from changes in the orbital overlap between the layers and from the modulation of the transport direction. | ||||
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Publisher | American Physical Society | Place of Publication | College Park, Md | Editor | |
Language | Wos | 000411460400001 | Publication Date | 2017-09-22 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2331-7019 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.808 | Times cited | 6 | Open Access | OpenAccess |
Notes | Approved | Most recent IF: 4.808 | |||
Call Number | UA @ lucian @ c:irua:146741 | Serial | 4785 | ||
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Author | de de Meux, A.J.; Pourtois, G.; Genoe, J.; Heremans, P. | ||||
Title | Defects in amorphous semiconductors : the case of amorphous indium gallium zinc oxide | Type | A1 Journal article | ||
Year | 2018 | Publication | Physical review applied | Abbreviated Journal | Phys Rev Appl |
Volume | 9 | Issue | 9 | Pages | 054039 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Based on a rational classification of defects in amorphous materials, we propose a simplified model to describe intrinsic defects and hydrogen impurities in amorphous indium gallium zinc oxide (a-IGZO). The proposed approach consists of organizing defects into two categories: point defects, generating structural anomalies such as metal-metal or oxygen-oxygen bonds, and defects emerging from changes in the material stoichiometry, such as vacancies and interstitial atoms. Based on first-principles simulations, it is argued that the defects originating from the second group always act as perfect donors or perfect acceptors. This classification simplifies and rationalizes the nature of defects in amorphous phases. In a-IGZO, the most important point defects are metal-metal bonds (or small metal clusters) and peroxides (O-O single bonds). Electrons are captured by metal-metal bonds and released by the formation of peroxides. The presence of hydrogen can lead to two additional types of defects: metal-hydrogen defects, acting as acceptors, and oxygen-hydrogen defects, acting as donors. The impact of these defects is linked to different instabilities observed in a-IGZO. Specifically, the diffusion of hydrogen and oxygen is connected to positive-and negative-bias stresses, while negative-bias illumination stress originates from the formation of peroxides. | ||||
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Publisher | American Physical Society | Place of Publication | College Park, Md | Editor | |
Language | Wos | 000433070900003 | Publication Date | 2018-05-25 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2331-7019 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.808 | Times cited | 7 | Open Access | OpenAccess |
Notes | Approved | Most recent IF: 4.808 | |||
Call Number | UA @ lucian @ c:irua:151497 | Serial | 5019 | ||
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Author | Yin, L.; Juneja, R.; Lindsay, L.; Pandey, T.; Parker, D.S. | ||||
Title | Semihard iron-based permanent-magnet materials | Type | A1 Journal article | ||
Year | 2021 | Publication | Physical Review Applied | Abbreviated Journal | Phys Rev Appl |
Volume | 15 | Issue | 2 | Pages | 024012 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Permanent magnets generally require a favorable, but difficult-to-achieve combination of high magnetization, Curie point, and magnetic anisotropy. Thus there have been few, if any, viable permanent magnets developed since the 1982 discovery of Nd2Fe14B [M. Sagawa, S. Fujimura, H. Yamamoto, Y. Matsuura, and S. Hirosawa, J. Appl. Phys. 57, 4094 (1985)]. Here we point out, both by direct first-principles calculations on the iron carbides and silicides Fe5C2, Fe5SiC, and Fe7C3 as well as a discussion of recent experimental findings, that there are numerous rare-earth-free iron-rich potential permanent-magnet materials with sufficient intrinsic magnetic properties to reasonably achieve room-temperature energy products of 20-25 MG Oe. This is substantially better than the performance of the best available rare-earth-free magnets based on ferrite, as well as shape-anisotropy-employing alnico. These magnets could plausibly fill, at low cost, the present performance “gap” [J. M. D. Coey, Scr. Mater. 67, 524 (2012)] between the best rare-earth-free magnets and rare-earth magnets such as Nd2Fe14B and Sm-Co. | ||||
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Language | Wos | 000614707800002 | Publication Date | 2021-02-05 | |
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Series Volume | Series Issue | Edition | |||
ISSN | 2331-7019 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.808 | Times cited | Open Access | Not_Open_Access | |
Notes | Approved | Most recent IF: 4.808 | |||
Call Number | UA @ admin @ c:irua:176624 | Serial | 6734 | ||
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Author | Sethu, K.K.V.; Ghosh, S.; Couet, S.; Swerts, J.; Sorée, B.; De Boeck, J.; Kar, G.S.; Garello, K. | ||||
Title | Optimization of tungsten beta-phase window for spin-orbit-torque magnetic random-access memory | Type | A1 Journal article | ||
Year | 2021 | Publication | Physical Review Applied | Abbreviated Journal | Phys Rev Appl |
Volume | 16 | Issue | 6 | Pages | 064009 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Switching induced by spin-orbit torque (SOT) is being vigorously explored, as it allows the control of magnetization using an in-plane current, which enables a three-terminal magnetic-tunnel-junction geometry with isolated read and write paths. This significantly improves the device endurance and the read stability, and allows reliable subnanosecond switching. Tungsten in the beta phase, beta-W, has the largest reported antidamping SOT charge-to-spin conversion ratio (theta(AD) approximate to -60%) for heavy metals. However, beta-W has a limitation when one is aiming for reliable technology integration: the beta phase is limited to a thickness of a few nanometers and enters the alpha phase above 4 nm in our samples when industry-relevant deposition tools are used. Here, we report our approach to extending the range of beta-W, while simultaneously improving the SOT efficiency by introducing N and O doping of W. Resistivity and XRD measurements confirm the extension of the beta phase from 4 nm to more than 10 nm, and transport characterization shows an effective SOT efficiency larger than -44.4% (reaching approximately -60% for the bulk contribution). In addition, we demonstrate the possibility of controlling and enhancing the perpendicular magnetic anisotropy of a storage layer (Co-Fe-B). Further, we integrate the optimized W(O, N) into SOT magnetic random-access memory (SOT-MRAM) devices and project that, for the same thickness of SOT material, the switching current decreases by 25% in optimized W(O, N) compared with our standard W. Our results open the path to using and further optimizing W for integration of SOT-MRAM technology. | ||||
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Language | Wos | 000729005800002 | Publication Date | 2021-12-03 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2331-7019 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.808 | Times cited | Open Access | Not_Open_Access | |
Notes | Approved | Most recent IF: 4.808 | |||
Call Number | UA @ admin @ c:irua:184832 | Serial | 7007 | ||
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Author | Tao, Z.H.; Dong, H.M.; Milošević, M.V.; Peeters, F.M.; Van Duppen, B. | ||||
Title | Tailoring dirac plasmons via anisotropic dielectric environment by design | Type | A1 Journal article | ||
Year | 2021 | Publication | Physical Review Applied | Abbreviated Journal | Phys Rev Appl |
Volume | 16 | Issue | 5 | Pages | 054030 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Dirac plasmons in a two-dimensional (2D) crystal are strongly affected by the dielectric properties of the environment, due to interaction of their electric field lines with the surrounding medium. Using graphene as a 2D reservoir of free carriers, one can engineer a material configuration that provides an anisotropic environment to the plasmons. In this work, we discuss the physical properties of Dirac plasmons in graphene surrounded by an arbitrary anisotropic dielectric and exemplify how h-BN-based heterostructures can be designed to bear the required anisotropic characteristics. We calculate how dielec-tric anisotropy impacts the spatial propagation of the plasmons and find that an anisotropy-induced plasmon mode emerges, together with a damping pathway, that stem from the out-of-plane off-diagonal elements in the dielectric tensor. Furthermore, we find that one can create hyperbolic plasmons by inher-iting the dielectric hyperbolicity of the designed material environment. Strong control over plasmon propagation patterns can be realized in a similar manner. Finally, we show that in this way one can also control the polarization of the light-matter excitations that constitute the plasmon. Taken together, our results promote the design of the dielectric environment as an effective path to tailor the plasmonic response of graphene on the nanoscopic level. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000720372500002 | Publication Date | 2021-11-15 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2331-7019 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.808 | Times cited | 2 | Open Access | Not_Open_Access |
Notes | Approved | Most recent IF: 4.808 | |||
Call Number | UA @ admin @ c:irua:184063 | Serial | 7028 | ||
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Author | Komulainen, S.; Verlackt, C.; Pursiainen, J.; Lajunen, M. | ||||
Title | Oxidation and degradation of native wheat starch by acidic bromate in water at room temperature | Type | A1 Journal article | ||
Year | 2013 | Publication | Carbohydrate Polymers | Abbreviated Journal | Carbohyd Polym |
Volume | 93 | Issue | 1 | Pages | 73-80 |
Keywords | A1 Journal article; Electron Microscopy for Materials Science (EMAT); | ||||
Abstract | Native wheat starch was oxidized by benign acidic bromate in water at room temperature. HPLC-ELSD study indicated that starch degraded in the course of oxidation but it still had a polymeric structure characterized by H-1, C-13, HSQC and HMBC NMR measurements. Products were generally water-soluble fragments but the use of a short reaction time and dilute reaction mixture yielded water-insoluble products. Titration of the products showed, that the increase of the starch content and reaction time increased the content of carbonyl and carboxyl groups in the range of 0.5-2.5% and 1.7-17.2%, respectively, in the product fragments. A mechanism for the oxidation reaction was proposed. (C) 2012 Elsevier Ltd. All rights reserved. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000316512900011 | Publication Date | 2012-06-21 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0144-8617; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.811 | Times cited | 32 | Open Access | |
Notes | Approved | Most recent IF: 4.811; 2013 IF: 3.916 | |||
Call Number | UA @ lucian @ c:irua:108288 | Serial | 2537 | ||
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Author | Batuk, D.; Tsirlin, A.A.; Filimonov, D.S.; Zakharov, K.V.; Volkova, O.S.; Vasiliev, A.; Hadermann, J.; Abakumov, A.M. | ||||
Title | Bi(3n+1)Ti7Fe(3n-3)O(9n+11) Homologous Series: Slicing Perovskite Structure with Planar Interfaces Containing Anatase-like Chains | Type | A1 Journal article | ||
Year | 2016 | Publication | Inorganic chemistry | Abbreviated Journal | Inorg Chem |
Volume | 55 | Issue | 55 | Pages | 1245-1257 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | The n = 3-6 members of a new perovskite-based homologous series Bi(3n+1)Ti7Fe(3n-3)O(9n+11) are reported. The crystal structure of the n = 3 Bi10Ti7Fe6O38 member is refined using a combination of X-ray and neutron powder diffraction data (a = 11.8511(2) A, b = 3.85076(4) A, c = 33.0722(6) A, S.G. Immm), unveiling the partially ordered distribution of Ti(4+) and Fe(3+) cations and indicating the presence of static random displacements of the Bi and O atoms. All Bi(3n+1)Ti7Fe(3n-3)O(9n+11) structures are composed of perovskite blocks separated by translational interfaces parallel to the (001)p perovskite planes. The thickness of the perovskite blocks increases with n, while the atomic arrangement at the interfaces remains the same. The interfaces comprise chains of double edge-sharing (Fe,Ti)O6 octahedra connected to the octahedra of the perovskite blocks by sharing edges and corners. This configuration shifts the adjacent perovskite blocks relative to each other over a vector (1/2)[110]p and creates S-shaped tunnels along the [010] direction. The tunnels accommodate double columns of the Bi(3+) cations, which stabilize the interfaces owing to the stereochemical activity of their lone electron pairs. The Bi(3n+1)Ti7Fe(3n-3)O(9n+11) structures can be formally considered either as intergrowths of perovskite modules and polysynthetically twinned modules of the Bi2Ti4O11 structure or as intergrowths of the 2D perovskite and 1D anatase fragments. Transmission electron microscopy (TEM) on Bi10Ti7Fe6O38 reveals that static atomic displacements of Bi and O inside the perovskite blocks are not completely random; they are cooperative, yet only short-range ordered. According to TEM, the interfaces can be laterally shifted with respect to each other over +/-1/3a, introducing an additional degree of disorder. Bi10Ti7Fe6O38 is paramagnetic in the 1.5-1000 K temperature range due to dilution of the magnetic Fe(3+) cations with nonmagnetic Ti(4+). The n = 3, 4 compounds demonstrate a high dielectric constant of 70-165 at room temperature. | ||||
Address | Center for Electrochemical Energy Storage, Skolkovo Institute of Science and Technology , Nobelya str. 3, 143026 Moscow, Russia | ||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | English | Wos | 000369356800031 | Publication Date | 2016-01-09 |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0020-1669 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.857 | Times cited | 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. | ||||
Address | |||||
Corporate Author | Thesis | ||||
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 | ||
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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 | ||||
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 | ||
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Author | Batuk, D.; Batuk, M.; Filimonov, D.S.; Zakharov, K.V.; Volkova, O.S.; Vasiliev, A.N.; Tyablikov, O.A.; Hadermann, J.; Abakumov, A.M. | ||||
Title | Crystal Structure, Defects, Magnetic and Dielectric Properties of the Layered Bi3n+1Ti7Fe3n-3,O9n+11 Perovskite-Anatase lntergrowths | Type | A1 Journal article | ||
Year | 2017 | Publication | Inorganic chemistry | Abbreviated Journal | Inorg Chem |
Volume | 56 | Issue | 56 | Pages | 931-942 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | The Bi3n+1Ti7Fe3n-3,O9n+11 materials are built of (001)(p) plane parallel perovskite blocks with a thickness of n (Ti,Fe)O-6 octahedra, separated by periodic translational interfaces. The interfaces are based on anatase-like chains of edge -sharing (Ti,Fe)O-6 octahedra. Together with the octahedra of the perovskite blocks, they create S-shaped tunnels stabilized by lone pair Bi3+ cations. In this work, the structure of the n = 4-6 Bi3n+1Ti7Fe3n-3,O9n+11 homologues is analyzed in detail using advanced transmission electron microscopy, powder X-ray diffraction, and Mossbauer spectroscopy. The connectivity of the anatase-like chains to the perovskite blocks results in,a 3ap periodicity along the interfaces, so that they can be located either on top of each other or with shifts of +/- a(p) along [100](p). The ordered arrangement of the interfaces gives rise to orthorhombic Immm and monoclinic A2/m polymorphs with the unit cell parameters a = 3a(p), b = b(p), c = 2(n + 1)c(p) and a = 3a(p), b = b(p), c = 2(n + 1)c(p) – a(p), respectively. While the n = 3 compound is orthorhombic, the monoclinic modification is more favorable in higher homologues. The Bi3n+1Ti7Fe3n-3,O9n+11 structures demonstrate intricate patterns of atomic displacements in the perovskite blocks, which are supported by the stereochemical activity of the Bi3+ cations. These patterns are coupled to the cationic coordination of the oxygen atoms in the (Ti,Fe)O-2 layers at the border of the perovskite blocks. The coupling is strong in the 1/ = 3, 4 homologues, but gradually reduces with the increasing thickness of the perovskite blocks, so that, in the n = 6 compound, the dominant mode of atomic displacements is aligned along the interface planes. The displacements in the adjacent perovskite blocks tend to order antiparallel, resulting in an overall antipolar structure. The Bi3n+1Ti7Fe3n-3,O9n+11 materials demonstrate an unusual diversity of structure defects. The n = 4-6 homologues are robust antiferromagnets below T-N = 135, 220, and 295 K, respectively. They show a high dielectric constant that weakly increases with temperature and is relatively insensitive to the Ti/Fe ratio. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Easton, Pa | Editor | ||
Language | Wos | 000392262400029 | Publication Date | 2016-12-25 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0020-1669 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.857 | Times cited | 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. | ||||
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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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Corporate Author | Thesis | ||||
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. | ||||
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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 | ||
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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) | ||||
Abstract | |||||
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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 | ||
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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. | ||||
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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 | ||
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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. | ||||
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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 | ||
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