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| Author | Mallick, S.; Khalsa, G.; Kaaret, J.Z.; Zhang, W.; Batuk, M.; Gibbs, A.S.; Hadermann, J.; Halasyamani, P.S.; Benedek, N.A.; Hayward, M.A. | ||||
| Title | The influence of the 6s² configuration of Bi³+ on the structures of A ' BiNb₂O₇ (A ' = Rb, Na, Li) layered perovskite oxides | Type | A1 Journal article | ||
Year  |
2021 | Publication | Journal of the Chemical Society : Dalton transactions | Abbreviated Journal | |
| Volume | 50 | Issue | 42 | Pages | 15359-15369 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Solid state compounds which exhibit non-centrosymmetric crystal structures are of great interest due to the physical properties they can exhibit. The 'hybrid improper' mechanism – in which two non-polar distortion modes couple to, and stabilize, a further polar distortion mode, yielding an acentric crystal structure – offers opportunities to prepare a range of novel non-centrosymmetric solids, but examples of compounds exhibiting acentric crystal structures stabilized by this mechanism are still relatively rare. Here we describe a series of bismuth-containing layered perovskite oxide phases, RbBiNb2O7, LiBiNb2O7 and NaBiNb2O7, which have structural frameworks compatible with hybrid-improper ferroelectricity, but also contain Bi3+ cations which are often observed to stabilize acentric crystal structures due to their 6s(2) electronic configurations. Neutron powder diffraction analysis reveals that RbBiNb2O7 and LiBiNb2O7 adopt polar crystal structures (space groups I2cm and B2cm respectively), compatible with stabilization by a trilinear coupling of non-polar and polar modes. The Bi3+ cations present are observed to enhance the magnitude of the polar distortions of these phases, but are not the primary driver for the acentric structure, as evidenced by the observation that replacing the Bi3+ cations with Nd3+ cations does not change the structural symmetry of the compounds. In contrast the non-centrosymmetric, but non-polar structure of NaBiNb2O7 (space group P2(1)2(1)2(1)) differs significantly from the centrosymmetric structure of NaNdNb2O7, which is attributed to a second-order Jahn-Teller distortion associated with the presence of the Bi3+ cations. | ||||
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| Language | Wos | 000706651100001 | Publication Date | 2021-10-05 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1477-9234 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | Times cited | Open Access | OpenAccess | ||
| Notes | Approved | Most recent IF: NA | |||
| Call Number | UA @ admin @ c:irua:182584 | Serial | 6893 | ||
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| Author | Quintelier, M.; Perkisas, T.; Poppe, R.; Batuk, M.; Hendrickx, M.; Hadermann, J. | ||||
| Title | Determination of spinel content in cycled Li1.2Ni0.13Mn0.54Co0.13O2 using three-dimensional electron diffraction and precession electron diffraction | Type | A1 Journal article | ||
| Year |
2021 | Publication | Symmetry-Basel | Abbreviated Journal | Symmetry-Basel |
| Volume | 13 | Issue | 11 | Pages | 1989-17 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Engineering Management (ENM); Electron microscopy for materials research (EMAT) | ||||
| Abstract | Among lithium battery cathode materials, Li1.2Ni0.13Mn0.54Co0.13O2 (LR-NMC) has a high theoretical capacity, but suffers from voltage and capacity fade during cycling. This is partially ascribed to transition metal cation migration, which involves the local transformation of the honeycomb layered structure to spinel-like nano-domains. Determination of the honeycomb layered/spinel phase ratio from powder X-ray diffraction data is hindered by the nanoscale of the functional material and the domains, diverse types of twinning, stacking faults, and the possible presence of the rock salt phase. Determining the phase ratio from transmission electron microscopy imaging can only be done for thin regions near the surfaces of the crystals, and the intense beam that is needed for imaging induces the same transformation to spinel as cycling does. In this article, it is demonstrated that the low electron dose sufficient for electron diffraction allows the collection of data without inducing a phase transformation. Using calculated electron diffraction patterns, we demonstrate that it is possible to determine the volume ratio of the different phases in the particles using a pair-wise comparison of the intensities of the reflections. Using this method, the volume ratio of spinel structure to honeycomb layered structure is determined for a submicron sized crystal from experimental three-dimensional electron diffraction (3D ED) and precession electron diffraction (PED) data. Both twinning and the possible presence of the rock salt phase are taken into account. After 150 charge-discharge cycles, 4% of the volume in LR-NMC particles was transformed irreversibly from the honeycomb layered structure to the spinel structure. The proposed method would be applicable to other multi-phase materials as well. | ||||
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| Language | Wos | 000815310500001 | Publication Date | 2021-10-21 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2073-8994 | ISBN | Additional Links | UA library record; WoS full record | |
| Impact Factor | 1.457 | Times cited | Open Access | OpenAccess | |
| Notes | Approved | Most recent IF: 1.457 | |||
| Call Number | UA @ admin @ c:irua:189468 | Serial | 7080 | ||
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| Author | Saveleva, V.A.; Wang, L.; Kasian, O.; Batuk, M.; Hadermann, J.; Gallet, J.-j.; Bournel, F.; Alonso-Vante, N.; Ozouf, G.; Beauger, C.; Mayrhofer, K.J.J.; Cherevko, S.; Gago, A.S.; Friedrich, K.A.; Zafeiratos, S.; Savinova, E.R. | ||||
| Title | Insight into the Mechanisms of High Activity and Stability of Iridium Supported on Antimony-Doped Tin Oxide Aerogel for Anodes of Proton Exchange Membrane Water Electrolyzers | Type | A1 Journal article | ||
| Year |
2020 | Publication | Acs Catalysis | Abbreviated Journal | Acs Catal |
| Volume | 10 | Issue | 4 | Pages | 2508-2516 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | The use of high amounts of iridium in industrial proton exchange membrane water electrolysers (PEMWE) could hinder their widespread use for the decarbonisation of society with hydrogen. Non-thermally oxidised Ir nanoparticles supported on antimony-doped tin oxide (SnO2:Sb, ATO) aerogel allow decreasing the use of the precious metal by more than 70 %, while enhancing the electro-catalytic activity and stability. To date the origin of these benefits remains unknown. Here we present clear evidence on the mechanisms that lead to the enhancement of the electrochemical properties of the catalyst. Operando near ambient pressure X-ray photoelectron spectroscopy on membrane electrode assemblies reveals a low degree of Ir oxidation, attributed to the oxygen spill-over from Ir to SnO2:Sb. Furthermore, the formation of highly unstable Ir(III) species is mitigated, while the decrease of Ir dissolution in Ir/SnO2:Sb is confirmed by inductively coupled plasma mass spectrometry (ICP-MS). The mechanisms that lead to the high activity and stability of Ir catalyst supported on SnO2:Sb aerogel for PEMWE are thus unveiled. | ||||
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| Language | Wos | 000516887400011 | Publication Date | 2020-02-21 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2155-5435 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 12.9 | Times cited | Open Access | OpenAccess | |
| Notes | The research leading to these results has received funding from the European Union’s Seventh Framework Program (FP7/2007-2013) for Fuel Cell and Hydrogen Joint Technology (FCH JU) Initiative under Grant No. 621237 (INSIDE). In addition, A.S.G. and C.B. thank the European Union’s Horizon 2020 research and innovation programme for funding the project PRETZEL under grant agreement No 779478 and it is supported by FCH JU. Solvay is acknowledged for providing Aquivion membrane and ionomer. | Approved | Most recent IF: 12.9; 2020 IF: 10.614 | ||
| Call Number | EMAT @ emat @c:irua:167147 | Serial | 6341 | ||
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| Author | Ciocarlan, R.-G.; Seftel, E.M.; Gavrila, R.; Suchea, M.; Batuk, M.; Mertens, M.; Hadermann, J.; Cool, P. | ||||
| Title | Spinel nanoparticles on stick-like Freudenbergite nanocomposites as effective smart-removal photocatalysts for the degradation of organic pollutants under visible light | Type | A1 Journal article | ||
| Year |
2020 | Publication | Journal Of Alloys And Compounds | Abbreviated Journal | J Alloy Compd |
| Volume | 820 | Issue | Pages | 153403 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA) | ||||
| Abstract | A series of mixed nanocomposite materials was synthetized, containing a Ferrite phase type Zn1-xNixFe2O4 and a Freudenbergite phase type Na2Fe2Ti6O16, where x = 0; 0.2; 0.4; 0.6; 0.8; 1. The choice for this combination is based on the good adsorption properties of Freudenbergite for dye molecules, and the small bandgap energy of Ferrite spinel, allowing activation of the catalysts under visible light irradiation. A two steps synthesis protocol was used to obtain the smart-removal nanocomposites. Firstly, the spinel structure was obtained via the co-precipitation route followed by the addition of the Ti-source and formation of the Freudenbergite system. The role of cations on the formation mechanism and an interesting interchange of cations between spinel and Freudenbergite structures was clarified by a TEM study. Part of the Ti4+ penetrated the spinel structure and, at the same time, part of the Fe3+ formed the Freudenbergite system. The photocatalytic activity was studied under visible light, reaching for the best catalysts a 67% and 40% mineralization degree for methylene blue and rhodamine 6G respectively, after 6 h of irradiation. In the same conditions, the well-known commercial P25 (Degussa) managed to mineralize only 12% and 3% of methylene blue and rhodamine 6G, respectively. Due to the remarkable magnetic properties of Ferrites, a convenient recovery and reuse of the catalysts is possible after the photocatalytic tests. Based on the excellent catalytic performance of the nanocomposites under visible light and their ease of separation out of the solution after the catalytic reaction, the newly developed composite catalysts are considered very effective for wastewater treatment. | ||||
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| Language | Wos | 000507854700130 | Publication Date | 2019-12-15 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0925-8388 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 6.2 | Times cited | Open Access | OpenAccess | |
| Notes | The authors acknowledge the FWO-Flanders (project nr. G038215N) for financial support. | Approved | Most recent IF: 6.2; 2020 IF: 3.133 | ||
| Call Number | EMAT @ emat @c:irua:166447 | Serial | 6342 | ||
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| Author | Rumyantseva, M.N.; Vladimirova, S.A.; Platonov, V.B.; Chizhov, A.S.; Batuk, M.; Hadermann, J.; Khmelevsky, N.O.; Gaskov, A.M. | ||||
| Title | Sub-ppm H2S sensing by tubular ZnO-Co3O4 nanofibers | Type | A1 Journal article | ||
| Year |
2020 | Publication | Sensors And Actuators B-Chemical | Abbreviated Journal | Sensor Actuat B-Chem |
| Volume | 307 | Issue | Pages | 127624 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Tubular ZnO – Co3O4 nanofibers were co-electrospun from polymer solution containing zinc and cobalt acetates. Phase composition, cobalt electronic state and element distribution in the fibers were investigated by XRD, SEM, HRTEM, HAADF-STEM with EDX mapping, and XPS. Bare ZnO has high selective sensitivity to NO and NO2, while ZnO-Co3O4 composites demonstrate selective sensitivity to H2S in dry and humid air. This effect is discussed in terms of transformation of cobalt oxides into cobalt sulfides and change in the acidity of ZnO oxide surface upon cobalt doping. Reduction in response and recovery time is attributed to the formation of a tubular structure facilitating gas transport through the sensitive layer. | ||||
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| Language | Wos | 000508110400059 | Publication Date | 2019-12-24 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0925-4005 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 5.401 | Times cited | Open Access | Not_Open_Access | |
| Notes | This work was supported by RFBR grants No. 18-03-00091 and No. 18-03-00580. | Approved | Most recent IF: NA | ||
| Call Number | EMAT @ emat @c:irua:166449 | Serial | 6343 | ||
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| Author | Hendrickx, M.; Tang, Y.; Hunter, E.C.; Battle, P.D.; Cadogan, Jm.; Hadermann, J. | ||||
| Title | CaLa2FeCoSbO9 and ALa2FeNiSbO9 (A = Ca, Sr, Ba): cation-ordered, inhomogeneous, ferrimagnetic perovskites | Type | A1 Journal article | ||
| Year |
2020 | Publication | Journal Of Solid State Chemistry | Abbreviated Journal | J Solid State Chem |
| Volume | 285 | Issue | Pages | 121226 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Polycrystalline samples of CaLa2FeCoSbO9 and ALa2FeNiSbO9 (A=Ca, Sr, Ba) have been prepared in solid-state reactions and studied by a combination of transmission electron microscopy, magnetometry, X-ray diffraction, neutron diffraction and Mössbauer spectroscopy. Diffraction and TEM showed that each shows 1:1 B-site ordering in which Co2+/Ni2+ and Sb5+ tend to occupy two distinct crystallographic sites while Fe3+ is distributed over both sites. While X-ray and neutron diffraction agreed that all four compositions are monophasic with space group P21/n, TEM revealed different levels of compositional inhomogeneity at the subcrystal scale, which, in the case of BaLa2FeNiSbO9, leads to the occurrence of both a P21/n and an I2/m phase. Magnetometry and neutron diffraction show that these perovskites are ferrimagnets with a G-type magnetic structure. Their relatively low magnetisation can be attributed to their inhomogeneity. This work demonstrates the importance of studying the microstructure of complex compositions. | ||||
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| Language | Wos | 000521107900017 | Publication Date | 2020-01-30 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0022-4596 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.3 | Times cited | Open Access | OpenAccess | |
| Notes | PDB, ECH, and JH acknowledge support from EPSRC under grant EP/M0189954/1. We would also like to thank E. Suard at ILL and I. Da Silva at ISIS for the experimental assistance they provided. | Approved | Most recent IF: 3.3; 2020 IF: 2.299 | ||
| Call Number | EMAT @ emat @c:irua:167137 | Serial | 6345 | ||
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| Author | Paulus, A.; Hendrickx, M.; Bercx, M.; Karakulina, O.M.; Kirsanova, M.A.; Lamoen, D.; Hadermann, J.; Abakumov, A.M.; Van Bael, M.K.; Hardy, A. | ||||
| Title | An in-depth study of Sn substitution in Li-rich/Mn-rich NMC as a cathode material for Li-ion batteries | Type | A1 Journal article | ||
| Year |
2020 | Publication | Journal of the Chemical Society : Dalton transactions | Abbreviated Journal | |
| Volume | 49 | Issue | 30 | Pages | 10486-10497 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Layered Li-rich/Mn-rich NMC (LMR-NMC) is characterized by high initial specific capacities of more than 250 mA h g(-1), lower cost due to a lower Co content and higher thermal stability than LiCoO2. However, its commercialisation is currently still hampered by significant voltage fade, which is caused by irreversible transition metal ion migration to emptied Li positionsviatetrahedral interstices upon electrochemical cycling. This structural change is strongly correlated with anionic redox chemistry of the oxygen sublattice and has a detrimental effect on electrochemical performance. In a fully charged state, up to 4.8 Vvs.Li/Li+, Mn4+ is prone to migrate to the Li layer. The replacement of Mn4+ for an isovalent cation such as Sn4+ which does not tend to adopt tetrahedral coordination and shows a higher metal-oxygen bond strength is considered to be a viable strategy to stabilize the layered structure upon extended electrochemical cycling, hereby decreasing voltage fade. The influence of Sn4+ on the voltage fade in partially charged LMR-NMC is not yet reported in the literature, and therefore, we have investigated the structure and the corresponding electrochemical properties of LMR-NMC with different Sn concentrations. We determined the substitution limit of Sn4+ in Li1.2Ni0.13Co0.13Mn0.54-xSnxO2 by powder X-ray diffraction and transmission electron microscopy to be x approximate to 0.045. The limited solubility of Sn is subsequently confirmed by density functional theory calculations. Voltage fade for x= 0 andx= 0.027 has been comparatively assessed within the 3.00 V-4.55 V (vs.Li/Li+) potential window, from which it is concluded that replacing Mn4+ by Sn4+ cannot be considered as a viable strategy to inhibit voltage fade within this window, at least with the given restricted doping level. | ||||
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| Language | Wos | 000555330900018 | Publication Date | 2020-07-09 | |
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| ISSN | 0300-9246; 1477-9226; 1472-7773 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 4 | Times cited | Open Access | OpenAccess | |
| Notes | ; The authors acknowledge Research Foundation Flanders (FWO) project number G040116N for funding. The authors are grateful to Dr Ken Elen and Greet Cuyvers (imo-imomec, UHasselt and imec) for respectively preliminary PXRD measurements and performing ICP-AES on the monometal precursors. Dr Dmitry Rupasov (Skolkovo Institute of Science and Technology) is acknowledged for performing TGA measurements on the metal sulfate precursors. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the FWO-Vlaanderen and the Flemish Government-department EWI. ; | Approved | Most recent IF: 4; 2020 IF: 4.029 | ||
| Call Number | UA @ admin @ c:irua:171149 | Serial | 6450 | ||
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| Author | Tunca, B.; Lapauw, T.; Callaert, C.; Hadermann, J.; Delville, R.; Caspi, E.'ad N.; Dahlqvist, M.; Rosen, J.; Marshal, A.; Pradeep, K.G.; Schneider, J.M.; Vleugels, J.; Lambrinou, K. | ||||
| Title | Compatibility of Zr₂AlC MAX phase-based ceramics with oxygen-poor, static liquid lead-bismuth eutectic | Type | A1 Journal article | ||
| Year |
2020 | Publication | Corrosion Science | Abbreviated Journal | Corros Sci |
| Volume | 171 | Issue | Pages | 108704-108719 | |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | This work investigates the compatibility of Zr2AlC MAX phase-based ceramics with liquid LBE, and proposes a mechanism to explain the observed local Zr2AlC/LBE interaction. The ceramics were exposed to oxygen-poor (C-O <= 2.2 x 10(-10) mass%), static liquid LBE at 500 degrees C for 1000 h. A new Zr-2(Al,Bi,Pb)C MAX phase solid solution formed in-situ in the LBE-affected Zr2AlC grains. Out-of-plane ordering was favorable in the new solid solution, whereby A-layers with high and low-Bi/Pb contents alternated in the crystal structure, in agreement with first-principles calculations. Bulk Zr-2(Al,Bi,Pb)C was synthesized by reactive hot pressing to study the crystal structure of the solid solution by neutron diffraction. | ||||
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| Language | Wos | 000537624600005 | Publication Date | 2020-04-27 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0010-938x | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 8.3 | Times cited | 3 | Open Access | Not_Open_Access |
| Notes | ; B.T. acknowledges the financial support of the SCK CEN Academy for Nuclear Science and Technology (Belgium). This research was partly funded by the European Atomic Energy Community's (Euratom) Seventh Framework Programme FP7/ 2007-2013 under Grant Agreement No. 604862 (FP7 MatISSE), the MYRRHA project (SCK CEN, Belgium), as well as by the Euratom research and training programme 2014-2018 under Grant Agreement No. 740415 (H2020 IL TROVATORE). The performed research falls within the framework of the EERA (European Energy Research Alliance) Joint Programme on Nuclear Materials (JPNM). The authors gratefully acknowledge the Hercules Foundation for Project AKUL/1319 (CombiS(T)EM)) and the Knut and Alice Wallenberg (KAW) foundation. The calculations were carried out using supercomputer resources provided by the Swedish National Infrastructure for Computing (SNIC) at the High Performance Computing Center North (HPC2N) and the PDC Center for High Performance Computing. E.N.C. thanks Offir Ozeri for his help in NPD data acquiring. ; | Approved | Most recent IF: 8.3; 2020 IF: 5.245 | ||
| Call Number | UA @ admin @ c:irua:170157 | Serial | 6475 | ||
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| Author | Vishwakarma, M.; Agrawal, K.; Hadermann, J.; Mehta, B.R. | ||||
| Title | Investigating the effect of sulphurization on volatility of compositions in Cu-poor and Sn-rich CZTS thin films | Type | A1 Journal article | ||
| Year |
2020 | Publication | Applied Surface Science | Abbreviated Journal | Appl Surf Sci |
| Volume | 507 | Issue | Pages | 145043 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | In the present work, the Cu-poor and Sn-rich CZTS thin films were prepared in order to study the volatility of Sn with respect to other components. Thin film compositions were kept intentionally Sn-rich to understand the behaviour of loss and segregation of Sn during sulphurization. The homogeneous composition distribution in precursor thin films turns heterogeneous with a change in morphology after sulphurization. The inability of identifying nanoscale secondary phases in CZTS thin film by conventional analytical techniques such as XRD and Raman, can be fulfilled by employing HAADF-STEM analysis. XPS and HAADF-STEM analyses provide the quantification of nanoscale secondary phases across the thin film and surface, respectively. The volatility of Sn was revealed in the form of segregation in the middle layer of CZTS cross-sectional lamella rather than loss to annealing atmosphere. It was observed that among the cations of CZTS, Sn segregates more than Cu, while Zn segregates least. The nanoscale spurious phases were observed to vary across different regions in the sulphurized CZTS sample. The reactive annealing lead to grain growth and formation of grain boundary features in the CZTS thin films, where annealing significantly modifies the potential difference and band bending at grain boundaries with respect to intra-grains. | ||||
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| Language | Wos | 000520021200053 | Publication Date | 2019-12-13 | |
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| ISSN | 0169-4332 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 6.7 | Times cited | 4 | Open Access | OpenAccess |
| Notes | ; Authors acknowledges support provided by DST, India in the forms of InSOL project. We also acknowledge Dr. Indrani Mishra for XPS measurements and DST-FIST Raman facility for Raman measurements. Manoj Vishwakarma acknowledges IIT Delhi, New Delhi, India for MHRD fellowship. Prof. B.R. Mehta acknowledges the support of the Schlumberger chair professorship. ; | Approved | Most recent IF: 6.7; 2020 IF: 3.387 | ||
| Call Number | UA @ admin @ c:irua:168603 | Serial | 6552 | ||
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| Author | Vishwakarma, M.; Varandani, D.; Hendrickx, M.; Hadermann, J.; Mehta, B.R. | ||||
| Title | Nanoscale photovoltage mapping in CZTSe/CuxSe heterostructure by using kelvin probe force microscopy | Type | A1 Journal article | ||
| Year |
2020 | Publication | Materials Research Express | Abbreviated Journal | |
| Volume | 7 | Issue | 1 | Pages | 016418 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | In the present work, kelvin probe force microscopy (KPFM) technique has been used to study the CZTSe/CuxSe bilayer interface prepared by multi-step deposition and selenization process of metal precursors. Transmission electron microscopy (TEM) confirmed the bilayer configuration of the CZTSe/CuxSe sample. Two configuration modes (surface mode and junction mode) in KPFM have been employed in order to measure the junction voltage under illumination conditions. The results show that CZTSe/CuxSe has small junction voltage of similar to 21 mV and the presence of CuxSe secondary phase in the CZTSe grain boundaries changes the workfunction of the local grain boundaries region. The negligible photovoltage difference between grain and grain boundaries in photovoltage image indicates that CuxSe phase deteriorates the higher photovoltage at grain boundaries normally observed in CZTSe based device. These results can be important for understanding the role of secondary phases in CZTSe based junction devices. | ||||
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| Language | Wos | 000520120900001 | Publication Date | 2019-12-27 | |
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| ISSN | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | ||
| Impact Factor | Times cited | Open Access | OpenAccess | ||
| Notes | ; Authors acknowledges support provided DST in the forms of InSOL and Indo-Swiss projects. We also acknowledge Joke Hadermann EMAT, University of Antwerp, Groenenborgerlaan 171, B-2020 Belgium for helping in TEM measurements. M V Manoj Vishwakarma acknowledges IIT Delhi for MHRD fellowship. Prof B R Mehta acknowledges the support of the Schlumberger chair professorship. M V also acknowledges the support of DST-FIST Raman facility. ; | Approved | Most recent IF: NA | ||
| Call Number | UA @ admin @ c:irua:167843 | Serial | 6567 | ||
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| Author | Parsons, T.G.; Hadermann, J.; Halasyamani, P.S.; Hayward, M.A. | ||||
| Title | Preparation of the noncentrosymmetric ferrimagnetic phase La0.9Ba0.1Mn0.96O2.43 by topochemical reduction | Type | A1 Journal article | ||
| Year |
2020 | Publication | Journal Of Solid State Chemistry | Abbreviated Journal | J Solid State Chem |
| Volume | 287 | Issue | Pages | 121356-121357 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Topochemical reduction of La0.9Ba0.1MnO3 with NaH at 225 degrees C yields the brownmillerite phase La0.9Ba0.1MnO2.5. However, reduction with CaH2 at 435 degrees C results in the formation of La0.9Ba0.1Mn0.96O2.43 via the deintercalation of both oxide anions and manganese cations from the parent perovskite phase. Electron and neutron diffraction data reveal La0.9Ba0.1Mn0.96O2.43 adopts a complex noncentrosymmetric structure, described in space group I23, confirmed by SHG measurements. Low-temperature neutron diffraction data reveal La0.9Ba0.1Mn0.96O2.43 adopts an ordered magnetic structure in which all the nearest neighbor interactions are antiferromagnetic. However, the presence of ordered manganese cation-vacancies results in a net ferrimagnetic structure with net saturated moment of 0.157(2) mu B per manganese center. | ||||
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| Language | Wos | 000533632700029 | Publication Date | 2020-04-05 | |
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0022-4596 | ISBN | Additional Links | UA library record; WoS full record | |
| Impact Factor | 3.3 | Times cited | Open Access | Not_Open_Access | |
| Notes | ; We thank the EPSRC for funding this work and E. Suard for assisting with the collection of the neutron powder diffraction data. PSH thanks the Welch Foundation (Grant E-1457) for support. ; | Approved | Most recent IF: 3.3; 2020 IF: 2.299 | ||
| Call Number | UA @ admin @ c:irua:169450 | Serial | 6583 | ||
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| Author | Han, Y.; Zeng, Y.; Hendrickx, M.; Hadermann, J.; Stephens, P.W.; Zhu, C.; Grams, C.P.; Hemberger, J.; Frank, C.; Li, S.; Wu, M.X.; Retuerto, M.; Croft, M.; Walker, D.; Yao, D.-X.; Greenblatt, M.; Li, M.-R. | ||||
| Title | Universal a-cation splitting in LiNbO₃-type structure driven by intrapositional multivalent coupling | Type | A1 Journal article | ||
| Year |
2020 | Publication | Journal Of The American Chemical Society | Abbreviated Journal | J Am Chem Soc |
| Volume | 142 | Issue | 15 | Pages | 7168-7178 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Understanding the electric dipole switching in multiferroic materials requires deep insight of the atomic-scale local structure evolution to reveal the ferroelectric mechanism, which remains unclear and lacks a solid experimental indicator in high-pressure prepared LiNbO3-type polar magnets. Here, we report the discovery of Zn-ion splitting in LiNbO3-type Zn2FeNbO6 established by multiple diffraction techniques. The coexistence of a high-temperature paraelectric-like phase in the polar Zn2FeNbO6 lattice motivated us to revisit other high-pressure prepared LiNbO3-type A(2)BB'O-6 compounds. The A-site atomic splitting (similar to 1.0-1.2 angstrom between the split-atom pair) in B/B'-mixed Zn2FeTaO6 and O/N-mixed ZnTaO2N is verified by both powder X-ray diffraction structural refinements and high angle annular dark field scanning transmission electron microscopy images, but is absent in single-B-site ZnSnO3. Theoretical calculations are in good agreement with experimental results and suggest that this kind of A-site splitting also exists in the B-site mixed Mn-analogues, Mn2FeMO6 (M = Nb, Ta) and anion-mixed MnTaO2N, where the smaller A-site splitting (similar to 0.2 angstrom atomic displacement) is attributed to magnetic interactions and bonding between A and B cations. These findings reveal universal A-site splitting in LiNbO3-type structures with mixed multivalent B/B', or anionic sites, and the splitting-atomic displacement can be strongly suppressed by magnetic interactions and/or hybridization of valence bands between d electrons of the A- and B-site cations. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000526300600046 | Publication Date | 2020-03-27 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0002-7863 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 15 | Times cited | 1 | Open Access | Not_Open_Access |
| Notes | ; This work was supported by the National Science Foundation of China (NSFC-21875287), the Program for Guangdong Introducing Innovative and Entrepreneurial Teams (2017ZT07C069), and an NSF-DMR-1507252 grant (U.S.). Use of the NSLS, Brookhaven National Laboratory, was supported by the DOE BES (DE-AC02-98CH10886). M.R. is thankful for the Spanish Juan de la Cierva grant FPDI-2013-17582. Y.Z. and D.-X.Y. are supported by NKRDPC-2018YFA0306001, NKRDPC-2017YFA0206203, NSFC-11974432, NSFG-2019A1515011337, the National Supercomputer Center in Guangzhou, and the Leading Talent Program of Guangdong Special Projects. Work on IOP, CAS, was supported by NSFC and MOST grants. A portion of this research at ORNL's Spallation Neutron Source was sponsored by the Scientific User Facilities Division, Office of Basic Energy Sciences, U.S. Department of Energy. J.H. and M.H. thank the FWO for support for the electron microscopy studies through grant G035619N. We thank beamline BL14B1 (Shanghai Synchrotron Radiation Facility) for providing beam time and help during the experiments. ; | Approved | Most recent IF: 15; 2020 IF: 13.858 | ||
| Call Number | UA @ admin @ c:irua:170294 | Serial | 6646 | ||
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| 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 | Kamminga, M.E.; Batuk, M.; Hadermann, J.; Clarke, S.J. | ||||
| Title | Misfit phase (BiSe)1.10NbSe2 as the origin of superconductivity in niobium-doped bismuth selenide | Type | A1 Journal article | ||
| Year |
2020 | Publication | Communications Materials | Abbreviated Journal | Commun Mater |
| Volume | 1 | Issue | 1 | Pages | 82 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Topological superconductivity is of great contemporary interest and has been proposed in doped Bi<sub>2</sub>Se<sub>3</sub>, in which electron-donating atoms such as Cu, Sr or Nb have been intercalated into the Bi<sub>2</sub>Se<sub>3</sub>structure. For Nb<sub><italic>x</italic></sub>Bi<sub>2</sub>Se<sub>3</sub>, with<italic>T</italic><sub>c</sub> ~ 3 K, it is assumed in the literature that Nb is inserted in the van der Waals gap. However, in this work an alternative origin for the superconductivity in Nb-doped Bi<sub>2</sub>Se<sub>3</sub>is established. In contrast to previous reports, it is deduced that Nb intercalation in Bi<sub>2</sub>Se<sub>3</sub>does not take place. Instead, the superconducting behaviour in samples of nominal composition Nb<sub><italic>x</italic></sub>Bi<sub>2</sub>Se<sub>3</sub>results from the (BiSe)<sub>1.10</sub>NbSe<sub>2</sub>misfit phase that is present in the sample as an impurity phase for small<italic>x</italic>(0.01 ≤ <italic>x</italic> ≤ 0.10) and as a main phase for large<italic>x</italic>(<italic>x</italic> = 0.50). The structure of this misfit phase is studied in detail using a combination of X-ray diffraction and transmission electron microscopy techniques. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000610580800001 | Publication Date | 2020-11-10 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2662-4443 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | Times cited | Open Access | OpenAccess | ||
| Notes | M.E.K. was supported by the Netherlands Organisation for Scientific Research (NWO, grant code 019.181EN.003). We also acknowledge support from the EPSRC (EP/ R042594/1, EP/P018874/1, EP/M020517/1) and the Leverhulme Trust (RPG-2018-377). J.H. acknowledges support from the University of Antwerp through BOF Grant No. 31445. We thank DLS Ltd for beam time (EE18786), Dr Clare Murray for assistance on I11 and Dr Jon Wade from the Department of Earth Sciences, University of Oxford for performing the SEM measurements. We also thank Dr Michal Dušak and Dr Václav Petřiček for their advice concerning the use of the Jana2006 software. | Approved | Most recent IF: NA | ||
| Call Number | EMAT @ emat @c:irua:176116 | Serial | 6705 | ||
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| 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. | ||||
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| 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 | ||
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| Author | Frolov, A.S.; Sanchez-Barriga, J.; Callaert, C.; Hadermann, J.; Fedorov, A., V; Usachov, D.Y.; Chaika, A.N.; Walls, B.C.; Zhussupbekov, K.; Shvets, I., V.; Muntwiler, M.; Amati, M.; Gregoratti, L.; Varykhalov, A.Y.; Rader, O.; Yashina, L., V. | ||||
| Title | Atomic and electronic structure of a multidomain GeTe crystal | Type | A1 Journal article | ||
| Year |
2020 | Publication | Acs Nano | Abbreviated Journal | Acs Nano |
| Volume | 14 | Issue | 12 | Pages | 16576-16589 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Renewed interest in the ferroelectric semi-conductor germanium telluride was recently triggered by the direct observation of a giant Rashba effect and a 30-year-old dream about a functional spin field-effect transistor. In this respect, all-electrical control of the spin texture in this material in combination with ferroelectric properties at the nanoscale would create advanced functionalities in spintronics and data information processing. Here, we investigate the atomic and electronic properties of GeTe bulk single crystals and their (111) surfaces. We succeeded in growing crystals possessing solely inversion domains of similar to 10 nm thickness parallel to each other. Using HAADF-TEM we observe two types of domain boundaries, one of them being similar in structure to the van der Waals gap in layered materials. This structure is responsible for the formation of surface domains with preferential Te-termination (similar to 68%) as we determined using photoelectron diffraction and XPS. The lateral dimensions of the surface domains are in the range of similar to 10-100 nm, and both Ge- and Te-terminations reveal no reconstruction. Using spin-ARPES we establish an intrinsic quantitative relationship between the spin polarization of pure bulk states and the relative contribution of different terminations, a result that is consistent with a reversal of the spin texture of the bulk Rashba bands for opposite configurations of the ferroelectric polarization within individual nanodomains. Our findings are important for potential applications of ferroelectric Rashba semiconductors in nonvolatile spintronic devices with advanced memory and computing capabilities at the nanoscale. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000603308800022 | Publication Date | 2020-11-02 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1936-0851 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 17.1 | Times cited | Open Access | OpenAccess | |
| Notes | Approved | Most recent IF: 17.1; 2020 IF: 13.942 | |||
| Call Number | UA @ admin @ c:irua:175027 | Serial | 6716 | ||
| Permanent link to this record | |||||
| Author | Saniz, R.; Sarmadian, N.; Partoens, B.; Batuk, M.; Hadermann, J.; Marikutsa, A.; Rumyantseva, M.; Gaskov, A.; Lamoen, D. | ||||
| Title | First-principles study of CO and OH adsorption on in-doped ZnO surfaces | Type | A1 Journal article | ||
| Year |
2019 | Publication | The journal of physics and chemistry of solids | Abbreviated Journal | J Phys Chem Solids |
| Volume | 132 | Issue | Pages | 172-181 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) | ||||
| Abstract | We present a first-principles computational study of CO and OH adsorption on non-polar ZnO (10¯10) surfaces doped with indium. The calculations were performed using a model ZnO slab. The position of the In dopants was varied from deep bulk-like layers to the surface layers. It was established that the preferential location of the In atoms is at the surface by examining the dependence of the defect formation energy as well as the surface energy on In location. The adsorption sites on the surface of ZnO and the energy of adsorption of CO molecules and OH-species were determined in connection to In doping. It was found that OH has higher bonding energy to the surface than CO. The presence of In atoms at the surface of ZnO is favorable for CO adsorption, resulting in an elongation of the C-O bond and in charge transfer to the surface. The effect of CO and OH adsorption on the electronic and conduction properties of surfaces was assessed. We conclude that In-doped ZnO surfaces should present a higher electronic response upon adsorption of CO. |
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000472124700023 | Publication Date | 2019-04-25 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0022-3697 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.059 | Times cited | 7 | Open Access | Not_Open_Access: Available from 26.04.2021 |
| Notes | FWO-Vlaanderen, G0D6515N ; ERA.Net RUS Plus, 096 ; VSC; HPC infrastructure of the University of Antwerp; FWO-Vlaanderen; Flemish Government-department EWI; | Approved | Most recent IF: 2.059 | ||
| Call Number | EMAT @ emat @UA @ admin @ c:irua:159656 | Serial | 5170 | ||
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| Author | Marikutsa, A.; Rumyantseva, M.; Gaskov, A.; Batuk, M.; Hadermann, J.; Sarmadian, N.; Saniz, R.; Partoens, B.; Lamoen, D. | ||||
| Title | Effect of zinc oxide modification by indium oxide on microstructure, adsorbed surface species, and sensitivity to CO | Type | A1 Journal article | ||
| Year |
2019 | Publication | Frontiers in materials | Abbreviated Journal | |
| Volume | 6 | Issue | 6 | Pages | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) | ||||
| Abstract | Additives in semiconductor metal oxides are commonly used to improve sensing behavior of gas sensors. Due to complicated effects of additives on the materials microstructure, adsorption sites and reactivity to target gases the sensing mechanism with modified metal oxides is a matter of thorough research. Herein, we establish the promoting effect of nanocrystalline zinc oxide modification by 1-7 at.% of indium on the sensitivity to CO gas due to improved nanostructure dispersion and concentration of active sites. The sensing materials were synthesized via an aqueous coprecipitation route. Materials composition, particle size and BET area were evaluated using X-ray diffraction, nitrogen adsorption isotherms, high-resolution electron microscopy techniques and EDX-mapping. Surface species of chemisorbed oxygen, OH-groups, and acid sites were characterized by probe molecule techniques and infrared spectroscopy. It was found that particle size of zinc oxide decreased and the BET area increased with the amount of indium oxide. The additive was observed as amorphous indium oxide segregated on agglomerated ZnO nanocrystals. The measured concentration of surface species was higher on In2O3-modified zinc oxide. With the increase of indium oxide content, the sensor response of ZnO/In2O3 to CO was improved. Using in situ infrared spectroscopy, it was shown that oxidation of CO molecules was enhanced on the modified zinc oxide surface. The effect of modifier was attributed to promotion of surface OH-groups and enhancement of CO oxidation on the segregated indium ions, as suggested by DFT in previous work. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000461540600001 | Publication Date | 2019-03-15 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2296-8016 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | Times cited | 11 | Open Access | OpenAccess | |
| Notes | ; Research was supported by the grant from Russian Science Foundation (project No. 18-73-00071). ; | Approved | Most recent IF: NA | ||
| Call Number | UA @ admin @ c:irua:158540 | Serial | 5205 | ||
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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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| 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. | ||||
| 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 | ||
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| Author | Tan, X.; Stephens, P.W.; Hendrickx, M.; Hadermann, J.; Segre, C.U.; Croft, M.; Kang, C.-J.; Deng, Z.; Lapidus, S.H.; Kim, S.W.; Jin, C.; Kotliar, G.; Greenblatt, M. | ||||
| Title | Tetragonal Cs1.17In0.81Cl3 : a charge-ordered indium halide perovskite derivative | Type | A1 Journal article | ||
| Year |
2019 | Publication | Chemistry of materials | Abbreviated Journal | Chem Mater |
| Volume | 31 | Issue | 6 | Pages | 1981-1989 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Polycrystalline samples of Cs1.17In0.81Cl3 were prepared by annealing a mixture of CsCl, InCl, and InCl3, stoichiometric for the targeted CsInCl3. Synchrotron powder X-ray diffraction refinement and chemical analysis by energy dispersive X-ray indicated that Cs1.17In0.81Cl3, a tetragonal distorted perovskite derivative (I4/m), is the thermodynamically stable product. The refined unit cell parameters and space group were confirmed by electron diffraction. In the tetragonal structure, In+ and In3+ are located in four different crystallographic sites, consistent with their corresponding bond lengths. In1, In2, and In3 are octahedrally coordinated, whereas In4 is at the center of a pentagonal bipyramid of Cl because of the noncooperative octahedral tilting of In4Cl6. The charged-ordered In+ and In3+ were also confirmed by X-ray absorption and Raman spectroscopy. Cs1.17In0.81Cl3 is the first example of an inorganic halide double perovskite derivative with charged-ordered In+ and In3+. Band structure and optical conductivity calculations were carried out with both generalized gradient approximation (GGA) and modified Becke-Johnson (mBJ) approach; the GGA calculations estimated the band gap and optical band gap to be 2.27 eV and 2.4 eV, respectively. The large and indirect band gap suggests that Cs1.17In0.81Cl3 is not a good candidate for photovoltaic application. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000462950400017 | Publication Date | 2019-02-19 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0897-4756 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 9.466 | Times cited | 6 | Open Access | OpenAccess |
| Notes | ; M.G. and X.T. were supported by the Center for Computational Design of Functional Strongly Correlated Materials and Theoretical Spectroscopy under DOE Grant No. DE-FOA-0001276. M.G. also acknowledges support of NSF-DMR-1507252 grant. G.K. and C.-J.K. were supported by the Air Force Office of Scientific Research. MRCAT operations are supported by the Department of Energy and the MRCAT member institutions. The use of the Advanced Photon Source at the Argonne National Laboratory was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357. The works at IOPCAS were supported by NSF & MOST of China through research projects. ; | Approved | Most recent IF: 9.466 | ||
| Call Number | UA @ admin @ c:irua:159413 | Serial | 5262 | ||
| Permanent link to this record | |||||
| Author | Tan, X.; McCabe, E.E.; Orlandi, F.; Manuel, P.; Batuk, M.; Hadermann, J.; Deng, Z.; Jin, C.; Nowik, I.; Herber, R.; Segre, C.U.; Liu, S.; Croft, M.; Kang, C.-J.; Lapidus, S.; Frank, C.E.; Padmanabhan, H.; Gopalan, V.; Wu, M.; Li, M.-R.; Kotliar, G.; Walker, D.; Greenblatt, M. | ||||
| Title | MnFe0.5Ru0.5O3 : an above-room-temperature antiferromagnetic semiconductor | Type | A1 Journal article | ||
| Year |
2019 | Publication | Journal of materials chemistry C : materials for optical and electronic devices | Abbreviated Journal | J Mater Chem C |
| Volume | 7 | Issue | 3 | Pages | 509-522 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | A transition-metal-only MnFe0.5Ru0.5O3 polycrystalline oxide was prepared by a reaction of starting materials MnO, MnO2, Fe2O3, RuO2 at 6 GPa and 1873 K for 30 minutes. A combination of X-ray and neutron powder diffraction refinements indicated that MnFe0.5Ru0.5O3 adopts the corundum (alpha-Fe2O3) structure type with space group R (3) over barc, in which all metal ions are disordered. The centrosymmetric nature of the MnFe0.5Ru0.5O3 structure is corroborated by transmission electron microscopy, lack of optical second harmonic generation, X-ray absorption near edge spectroscopy, and Mossbauer spectroscopy. X-ray absorption near edge spectroscopy of MnFe0.5Ru0.5O3 showed the oxidation states of Mn, Fe, and Ru to be 2+/3+, 3+, and similar to 4+, respectively. Resistivity measurements revealed that MnFe0.5Ru0.5O3 is a semiconductor. Magnetic measurements and magnetic structure refinements indicated that MnFe0.5Ru0.5O3 orders antiferromagnetically around 400 K, with magnetic moments slightly canted away from the c axis. Fe-57 Mossbauer confirmed the magnetic ordering and Fe3+ (S = 5/2) magnetic hyperfine splitting. First principles calculations are provided to understand the electronic structure more thoroughly. A comparison of synthesis and properties of MnFe0.5Ru0.5O3 and related corundum Mn2BB'O-6 derivatives is discussed. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000458780300004 | Publication Date | 2018-11-27 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2050-7526; 2050-7534 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 5.256 | Times cited | 1 | Open Access | Not_Open_Access |
| Notes | ; M. G. thanks the NSF-DMR-1507252 grant of the United States. X. T. was supported by the “Center for Computational Design of Functional Strongly Correlated Materials and Theoretical Spectroscopy'' under DOE Grant No. DE-FOA-0001276. G. K. and C. J. K. were supported by the Air Force Office of Scientific Research. MRCAT operations are supported by the Department of Energy and the MRCAT member institutions. EEM is grateful to the Leverhulme Trust (RPG-2017-362). M. R. Li and M. X. Wu are supported by the ”One Thousand Youth Talents'' Program of China. Use of the Advanced Photon Source at Argonne National Laboratory was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357. Part of this research used the ISS, 8-ID and TES, 8-BM beamlines at the National Synchrotron Light Source II (NSLS-II), a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Brookhaven National Laboratory under Contract No. DE-SC0012704. Without the valuable aid/support of the NSLS-II staff scientists Eli Stavitski, Klaus Attenkofer, and Paul Northrup this phase of the work could not have been performed. The work at IOPCAS was supported by NSF & MOST of China through research projects. H. R. and V. G. acknowledge NSF-MRSEC Center for Nanoscale Science at Penn State through the grant number DMR-1420620. The authors would like to thank Ms Jean Hanley at Lamont-Doherty Earth Observatory in Columbia University for making the high-pressure assemblies. The authors acknowledge the science and technology facility council (STFC) UK for the provision of neutron beam time. The authors would like to thank Daniel Nye for help on the Rigaku SmartLab X-ray diffractometer instrument in the Materials Characterization Laboratory at the ISIS Neutron and Muon Source. ; | Approved | Most recent IF: 5.256 | ||
| Call Number | UA @ admin @ c:irua:157564 | Serial | 5264 | ||
| Permanent link to this record | |||||
| Author | Callaert, C.; Bercx, M.; Lamoen, D.; Hadermann, J. | ||||
| Title | Interstitial defects in the van der Waals gap of Bi2Se3 | Type | A1 Journal article | ||
| Year |
2019 | Publication | Acta Crystallographica. Section B: Structural Science, Crystal Engineering and Materials (Online) | Abbreviated Journal | Acta Crystallogr B |
| Volume | 75 | Issue | 4 | Pages | 717-732 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Bi<sub>2</sub>Se<sub>3</sub>is a thermoelectric material and a topological insulator. It is slightly conducting in its bulk due to the presence of defects and by controlling the defects different physical properties can be fine tuned. However, studies of the defects in this material are often contradicting or inconclusive. Here, the defect structure of Bi<sub>2</sub>Se<sub>3</sub>is studied with a combination of techniques: high-resolution scanning transmission electron microscopy (HR-STEM), high-resolution energy-dispersive X-ray (HR-EDX) spectroscopy, precession electron diffraction tomography (PEDT), X-ray diffraction (XRD) and first-principles calculations using density functional theory (DFT). Based on these results, not only the observed defects are discussed, but also the discrepancies in results or possibilities across the techniques. STEM and EDX revealed interstitial defects with mainly Bi character in an octahedral coordination in the van der Waals gap, independent of the applied sample preparation method (focused ion beam milling or cryo-crushing). The inherent character of these defects is supported by their observation in the structure refinement of the EDT data. Moreover, the occupancy probability of the defects determined by EDT is inversely proportional to their corresponding DFT calculated formation energies. STEM also showed the migration of some atoms across and along the van der Waals gap. The kinetic barriers calculated using DFT suggest that some paths are possible at room temperature, while others are most probably beam induced. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000480512600024 | Publication Date | 2019-08-01 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2052-5206 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.032 | Times cited | Open Access | ||
| Notes | University of Antwerp, 31445 ; Acknowledgements We thank Artem M. Abakumov for providing the original Bi2Se3 sample and are also very grateful to Christophe Vandevelde for trying repeatedly to get good single crystal X-ray diffraction data out of each of our failed attempts at making an undeformed single crystal. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the FWO-Vlaanderen and the Flemish Government-department EWI. | Approved | Most recent IF: 2.032 | ||
| Call Number | EMAT @ emat @c:irua:161847 | Serial | 5295 | ||
| Permanent link to this record | |||||
| Author | Gvozdetskyi, V.; Bhaskar, G.; Batuk, M.; Zhao, X.; Wang, R.; Carnahan, S.L.; Hanrahan, M.P.; Ribeiro, R.A.; Canfield, P.C.; Rossini, A.J.; Wang, C.-Z.; Ho, K.-M.; Hadermann, J.; Zaikina, J.V. | ||||
| Title | Computationally Driven Discovery of a Family of Layered LiNiB Polymorphs | Type | A1 Journal article | ||
| Year |
2019 | Publication | Angewandte Chemie: international edition in English | Abbreviated Journal | Angew Chem Int Edit |
| Volume | 58 | Issue | 44 | Pages | 15855-15862 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Two novel lithium nickel boride polymorphs RT-LiNiB and HT-LiNiB with layered crystal structures are reported. This family of compounds was theoretically predicted by using the adaptive genetic algorithm (AGA) and subsequently synthesized via a hydride route with LiH precursor as a lithium source. Being unique among the known ternary transition metal borides, the LiNiB structures feature Li layers alternating with nearly planar [NiB] layers, composed of Ni hexagonal rings centered by B-B pairs. A comprehensive study using a combination of single crystal/synchrotron powder X-ray diffraction data, solid-state 7Li and 11B NMR, scanning transmission electron microscopy, quantum chemistry calculations, and magnetism has shed light on the intrinsic features of these polymorphic compounds. The unique layered structures of LiNiB compounds make them ultimate precursors to further study their exfoliation, paving a way toward two-dimensional transition metal borides, MBenes. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000491219600038 | Publication Date | 2019-10-28 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1433-7851 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 11.994 | Times cited | Open Access | ||
| Notes | the Gordon and Betty Moore Foundation’s EPiQS Initiative through Grant GBMF4411. The Ames Laboratory is operated for the U.S. Department of Energy by Iowa State University under contract #DE-AC02-07CH11358. Use of the Advanced Photon Source at Argonne National Laboratory was supported by the U. S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357. | Approved | Most recent IF: 11.994 | ||
| Call Number | EMAT @ emat @c:irua:164752 | Serial | 5433 | ||
| Permanent link to this record | |||||
| Author | Hadermann, J.; Palatinus, L. | ||||
| Title | Introducton to the special issue on electron crystallography | Type | Editorial | ||
| Year |
2019 | Publication | And Materials | Abbreviated Journal | |
| Volume | 75 | Issue | 4 | Pages | 462-462 |
| Keywords | Editorial; Electron microscopy for materials research (EMAT) | ||||
| Abstract | |||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000480512600028 | Publication Date | 2019-08-05 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | ||
| Impact Factor | Times cited | 2 | Open Access | ||
| Notes | ; ; | Approved | Most recent IF: NA | ||
| Call Number | UA @ admin @ c:irua:161845 | Serial | 5389 | ||
| Permanent link to this record | |||||
| Author | Chizhov, A.; Vasiliev, R.; Rumyantseva, M.; Krylov, I.; Drozdov, K.; Batuk, M.; Hadermann, J.; Abakumov, A.; Gaskov, A. | ||||
| Title | Light-activated sub-ppm NO2 detection by hybrid ZnO/QD nanomaterials vs. charge localization in core-shell QD | Type | A1 Journal article | ||
| Year |
2019 | Publication | Frontiers in materials | Abbreviated Journal | |
| Volume | 6 | Issue | 6 | Pages | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | New hybrid materials-photosensitized nanocomposites containing nanocrystal heterostructures with spatial charge separation, show high response for practically important sub-ppm level NO2 detection at room temperature. Nanocomposites ZnO/CdSe, ZnO/(CdS@CdSe), and ZnO/(ZnSe@CdS) were obtained by the immobilization of nanocrystals-colloidal quantum dots (QDs), on the matrix of nanocrystalline ZnO. The formation of crystalline core-shell structure of QDs was confirmed by HAADF-STEM coupled with EELS mapping. Optical properties of photosensitizers have been investigated by optical absorption and luminescence spectroscopy combined with spectral dependences of photoconductivity, which proved different charge localization regimes. Photoelectrical and gas sensor properties of nanocomposites have been studied at room temperature under green light (max = 535 nm) illumination in the presence of 0.12-2 ppm NO2 in air. It has been demonstrated that sensitization with type II heterostructure ZnSe@CdS with staggered gap provides the rapid growth of effective photoresponse with the increase in the NO2 concentration in air and the highest sensor sensitivity toward NO2. We believe that the use of core-shell QDs with spatial charge separation opens new possibilities in the development of light-activated gas sensors working without thermal heating. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000487641600002 | Publication Date | 2019-09-24 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2296-8016 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | Times cited | 1 | Open Access | ||
| Notes | ; This work was financially supported by RFBR grant No. 1653-76001 (RFBR – ERA.Net FONSENS 096) and in part by a grant from the St. Petersburg State University – Event 3-2018 (id: 26520408). AC acknowledges support from the RFBR grant No. 18-33-01004. ; | Approved | Most recent IF: NA | ||
| Call Number | UA @ admin @ c:irua:163776 | Serial | 5390 | ||
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| Author | Chin, C.-M.; Battle, P.D.; Hunter, E.C.; Avdeev, M.; Hendrickx, M.; Hadermann, J. | ||||
| Title | Stabilisation of magnetic ordering in La3Ni2-xCuxB'O9(B'=Sb,Ta,Nb) by the introduction of Cu2+ | Type | A1 Journal article | ||
| Year |
2019 | Publication | Journal of solid state chemistry | Abbreviated Journal | J Solid State Chem |
| Volume | 276 | Issue | 276 | Pages | 164-172 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | La3Ni2-xCuxB'O-9 (x = 0.25; B' = Sb, Ta, Nb: x = 0.5; B' = Nb) have been synthesized and characterised by transmission electron microscopy, neutron diffraction and magnetometry. Each adopts a perovskite-like structure (space group P2(1)/n) with two crystallographically-distinct six-coordinate sites, one occupied by a disordered arrangement of Ni2+ and Cu2+ and the other by a disordered similar to 1:2 distribution of Ni2+ and B'(5+), although some Cu2+ is found on the latter site when x = 0.5. Each composition undergoes a magnetic transition in the range 90 <= T/K <= 130 and shows a spontaneous magnetisation at 5 K; the transition temperature always exceeds that of the x = 0 composition by >= 30 K. A long-range ordered G-type ferrimagnetic structure is present in each composition, but small relaxor domains are also present. This contrasts with the pure relaxor and spin-glass behaviour of x = 0, B' = Ta, Nb, respectively. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000473372400023 | Publication Date | 2019-05-09 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0022-4596 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.299 | Times cited | 2 | Open Access | |
| Notes | ; We thank EPSRC for funding through grant EP/M0189541. CMC thanks the Croucher Foundation and the University of Oxford for the award of a graduate scholarship. ; | Approved | Most recent IF: 2.299 | ||
| Call Number | UA @ admin @ c:irua:161199 | Serial | 5396 | ||
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| Author | Hadermann, J.; Abakumov, A.M. | ||||
| Title | Structure solution and refinement of metal-ion battery cathode materials using electron diffraction tomography | Type | A1 Journal article | ||
| Year |
2019 | Publication | And Materials | Abbreviated Journal | |
| Volume | 75 | Issue | 4 | Pages | 485-494 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | The applicability of electron diffraction tomography to the structure solution and refinement of charged, discharged or cycled metal-ion battery positive electrode (cathode) materials is discussed in detail. As these materials are often only available in very small amounts as powders, the possibility of obtaining single-crystal data using electron diffraction tomography (EDT) provides unique access to crucial information complementary to X-ray diffraction, neutron diffraction and high-resolution transmission electron microscopy techniques. Using several examples, the ability of EDT to be used to detect lithium and refine its atomic position and occupancy, to solve the structure of materials ex situ at different states of charge and to obtain in situ data on structural changes occurring upon electrochemical cycling in liquid electrolyte is discussed. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000480512600002 | Publication Date | 2019-08-05 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | ||
| Impact Factor | Times cited | 2 | Open Access | ||
| Notes | ; The following funding is acknowledged: Fonds Wetenschappelijk Onderzoek (grant No. G040116N); Russian Foundation of Basic Research (grant No. 17-03-00370-a). ; | Approved | Most recent IF: NA | ||
| Call Number | UA @ admin @ c:irua:161846 | Serial | 5397 | ||
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| Author | Piorra, A.; Hrkac, V.; Wolff, N.; Zamponi, C.; Duppel, V.; Hadermann, J.; Kienle, L.; Quandt, E. | ||||
| Title | (Ba0.85Ca0.15)(Ti0.9Zr0.1)O3 thin films prepared by PLD : relaxor properties and complex microstructure | Type | A1 Journal article | ||
| Year |
2019 | Publication | Journal of applied physics | Abbreviated Journal | J Appl Phys |
| Volume | 125 | Issue | 24 | Pages | 244103 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Ferroelectric lead-free thin films of the composition (Ba0.85Ca0.15)(Ti0.9Zr0.1)O-3 (BCZT) were deposited by pulsed laser deposition on Pt/TiO2/SiO2/Si substrates using a ceramic BCZT target prepared by a conventional solid state reaction. The target material itself shows a piezoelectric coefficient of d(33)=640pm/V. The (111) textured thin films possess a thickness of up to 1.1 mu m and exhibit a clamped piezoelectric response f of up to 190pm/V, a dielectric coefficient of (r)=2000 at room temperature, and a pronounced relaxor behavior. As indicated by transmission electron microscopy, the thin films are composed of longitudinal micrometersized columns with similar to 100nm lateral dimension that are separated at twin- and antiphase boundaries. The superposition phenomena according to this columnar growth were simulated based on suitable supercells. The major structural component is described as a tetragonal distorted variant of the perovskite parent type; however, frequently coherently intergrown nanodomains were observed indicating a much more complex structure that is characterized by a 7-layer modulation along the growth direction of the films. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000474439600002 | Publication Date | 2019-06-25 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0021-8979; 1089-7550 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.068 | Times cited | Open Access | ||
| Notes | ; The authors want to thank Dr. Martina Luysberg and Dr. Lothar Houben from the Ernst Ruska Centre in Julich for discussion and CS-corrected microscopy. Funding of this work via the DFG (No. CRC1261) “Magnetoelectric Sensors: From Composite Materials to Biomagnetic Diagnostics” and the PAK902 is gratefully acknowledged. ; | Approved | Most recent IF: 2.068 | ||
| Call Number | UA @ admin @ c:irua:161310 | Serial | 5399 | ||
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| Author | Retuerto, M.; Calle-Vallejo, F.; Pascual, L.; Lumbeeck, G.; Fernandez-Diaz, M.T.; Croft, M.; Gopalakrishnan, J.; Pena, M.A.; Hadermann, J.; Greenblatt, M.; Rojas, S. | ||||
| Title | La1.5Sr0.5NiMn0.5Ru0.5O6 double perovskite with enhanced ORR/OER bifunctional catalytic activity | Type | A1 Journal article | ||
| Year |
2019 | Publication | ACS applied materials and interfaces | Abbreviated Journal | Acs Appl Mater Inter |
| Volume | 11 | Issue | 24 | Pages | 21454-21464 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Perovskites (ABO(3)) with transition metals in active B sites are considered alternative catalysts for the water oxidation to oxygen through the oxygen evolution reaction (OER) and for the oxygen reduction through the oxygen reduction reaction (ORR) back to water. We have synthesized a double perovskite (A(2)BB'O-6) with different cations in A, B, and B' sites, namely, ((La15Sr0.5)-Sr-.)(A)(Ni0.5Mn0.5)(B)(Ni0.5Ru0.5)(B)O-6 (LSNMR), which displays an outstanding OER/ORR bifunctional performance. The composition and structure of the oxide has been determined by powder X-ray diffraction, powder neutron diffraction, and transmission electron microscopy to be monoclinic with the space group P2(1)/n and with cationic ordering between the ions in the B and B' sites. X-ray absorption near-edge spectroscopy suggests that LSNMR presents a configuration of similar to Ni2+, similar to Mn4+, and similar to Ru5+. This bifunctional catalyst is endowed with high ORR and OER activities in alkaline media, with a remarkable bifunctional index value of similar to 0.83 V (the difference between the potentials measured at -1 mA cm(-2) for the ORR and +10 mA cm(-2) for the OER). The ORR onset potential (E-onset) of 0.94 V is among the best reported to date in alkaline media for ORR-active perovskites. The ORR mass activity of LSNMR is 1.1 A g(-1) at 0.9 V and 7.3 A g(-1) at 0.8 V. Furthermore, LSNMR is stable in a wide potential window down to 0.05 V. The OER potential to achieve a current density of 10 mA cm(-2) is 1.66 V. Density functional theory calculations demonstrate that the high ORR/OER activity of LSNMR is related to the presence of active Mn sites for the ORR- and Ru-active sites for the OER by virtue of the high symmetry of the respective reaction steps on those sites. In addition, the material is stable to ORR cycling and also considerably stable to OER cycling. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000472683300019 | Publication Date | 2019-05-30 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1944-8244 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 7.504 | Times cited | 12 | Open Access | |
| Notes | ; This work was supported by the ENE2016-77055-C3-3-R project from the Spanish Ministry of Economy and Competitiveness (MINECO) and PIE 201480E122 from CSIC. M.R. thanks MINECO's Juan de la Cierva program for a grant (FPDI-2013-17582). F.C.-V. thanks the Spanish MEC for a Ramon y Cajal research contract (RYC-2015-18996). M.G. acknowledges the support from NSF-DMR-1507252 grant, NJ, USA. ; | Approved | Most recent IF: 7.504 | ||
| Call Number | UA @ admin @ c:irua:161320 | Serial | 5400 | ||
| Permanent link to this record | |||||