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| Author | Khelifi, S.; Brammertz, G.; Choubrac, L.; Batuk, M.; Yang, S.; Meuris, M.; Barreau, N.; Hadermann, J.; Vrielinck, H.; Poelman, D.; Neyts, K.; Vermang, B.; Lauwaert, J. | ||||
| Title | The path towards efficient wide band gap thin-film kesterite solar cells with transparent back contact for viable tandem application | Type | A1 Journal article | ||
| Year | 2021 | Publication | Solar Energy Materials And Solar Cells | Abbreviated Journal | Sol Energ Mat Sol C |
| Volume | 219 | Issue | Pages | 110824 | |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract  |
Wide band gap thin-film kesterite solar cell based on non-toxic and earth-abundant materials might be a suitable candidate as a top cell for tandem configuration in combination with crystalline silicon as a bottom solar cell. For this purpose and based on parameters we have extracted from electrical and optical characterization techniques of Cu2ZnGeSe4 absorbers and solar cells, a model has been developed to describe the kesterite top cell efficiency limitations and to investigate the different possible configurations with transparent back contact for fourterminal tandem solar cell application. Furthermore, we have studied the tandem solar cell performance in view of the band gap and the transparency of the kesterite top cell and back contact engineering. Our detailed analysis shows that a kesterite top cell with efficiency > 14%, a band gap in the range of 1.5-1.7 eV and transparency above 80% at the sub-band gaps photons energies are required to achieve a tandem cell with higher efficiency than with a single silicon solar cell. | ||||
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| Language | Wos | 000591683500002 | Publication Date | 2020-10-08 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0927-0248 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 4.784 | Times cited | Open Access | OpenAccess | |
| Notes | The authors would like to acknowledge the SWInG project financed by the European Union’s Horizon 2020 research and innovation programme under grant agreement No 640868 and the Research Foundation Flanders-Hercules Foundation (FWO-Vlaanderen, project No AUGE/13/16:FT-IMAGER). | Approved | Most recent IF: 4.784 | ||
| Call Number | EMAT @ emat @c:irua:174337 | Serial | 6706 | ||
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| Author | 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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| 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 | Juchtmans, R.; Béché, A.; Abakumov, A.; Batuk, M.; Verbeeck, J. | ||||
| Title | Using electron vortex beams to determine chirality of crystals in transmission electron microscopy | Type | A1 Journal article | ||
| Year | 2015 | Publication | Physical review : B : condensed matter and materials physics | Abbreviated Journal | Phys Rev B |
| Volume | 91 | Issue | 91 | Pages | 094112 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract |
We investigate electron vortex beams elastically scattered on chiral crystals. After deriving a general expression for the scattering amplitude of a vortex electron, we study its diffraction on point scatterers arranged on a helix. We derive a relation between the handedness of the helix and the topological charge of the electron vortex on one hand and the symmetry of the higher-order Laue zones in the diffraction pattern on the other for kinematically and dynamically scattered electrons. We then extend this to atoms arranged on a helix as found in crystals which belong to chiral space groups and propose a method to determine the handedness of such crystals by looking at the symmetry of the diffraction pattern. In contrast to alternative methods, our technique does not require multiple scattering, which makes it possible to also investigate extremely thin samples in which multiple scattering is suppressed. In order to verify the model, elastic scattering simulations are performed, and an experimental demonstration on Mn2Sb2O7 is given in which we find the sample to belong to the right-handed variant of its enantiomorphic pair. This demonstrates the usefulness of electron vortex beams to reveal the chirality of crystals in a transmission electron microscope and provides the required theoretical basis for further developments in this field. | ||||
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| Language | Wos | 000352017000002 | Publication Date | 2015-03-27 | |
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| Series Volume | Series Issue | Edition | |||
| ISSN | 1098-0121;1550-235X; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 54 | Open Access | |
| Notes | Fwo; 312483 Esteem2; 278510 Vortex; esteem2jra1; esteem2jra2 ECASJO_; | Approved | Most recent IF: 3.836; 2015 IF: 3.736 | ||
| Call Number | c:irua:125512 c:irua:125512 | Serial | 3825 | ||
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| Author | Brammertz, G.; Buffiere, M.; Verbist, C.; Bekaert, J.; Batuk, M.; Hadermann, J.; et al. | ||||
| Title | Process variability in Cu2ZnSnSe4 solar cell devices: Electrical and structural investigations | Type | P1 Proceeding | ||
| Year | 2015 | Publication | The conference record of the IEEE Photovoltaic Specialists Conference T2 – IEEE 42nd Photovoltaic Specialist Conference (PVSC), JUN 14-19, 2015, New Orleans, LA | Abbreviated Journal | |
| Volume | Issue | Pages | |||
| Keywords | P1 Proceeding; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) | ||||
| Abstract |
We have fabricated 9.7% efficient Cu2ZnSnSe4/CdS/ZnO solar cells by H2Se selenization of sequentially sputtered metal layers. Despite the good efficiency obtained, process control appears to be difficult. In the present contribution we compare the electrical and physical properties of two devices with nominal same fabrication procedure, but 1% and 9.7% power conversion efficiency respectively. We identify the problem of the lower performing device to be the segregation of ZnSe phases at the backside of the sample. This ZnSe seems to be the reason for the strong bias dependent photocurrent observed in the lower performing devices, as it adds a potential barrier for carrier collection. The reason for the different behavior of the two nominally same devices is not fully understood, but speculated to be related to sputtering variability. | ||||
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| Publisher | Ieee | Place of Publication | New york | Editor | |
| Language | Wos | Publication Date | |||
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| ISSN | 978-1-4799-7944-8 | ISBN | Additional Links | UA library record; WoS full record | |
| Impact Factor | Times cited | Open Access | |||
| Notes | Approved | Most recent IF: NA | |||
| Call Number | UA @ lucian @ c:irua:132335 | Serial | 4229 | ||
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| Author | Zaikina, J.V.; Batuk, M.; Abakumov, A.M.; Navrotsky, A.; Kauziarich, S.M. | ||||
| Title | Facile synthesis of Ba1-xKxFe2As2 superconductors via hydride route | Type | A1 Journal article | ||
| Year | 2014 | Publication | Journal of the American Chemical Society | Abbreviated Journal | J Am Chem Soc |
| Volume | 136 | Issue | 48 | Pages | 16932-16939 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract |
We have developed a fast, easy, and scalable synthesis method for Ba1xKxFe2As2 (0 ≤ x ≤ 1) superconductors using hydrides BaH2 and KH as a source of barium and potassium metals. Synthesis from hydrides provides better mixing and easier handling of the starting materials, consequently leading to faster reactions and/or lower synthesis temperatures. The reducing atmosphere provided by the evolved hydrogen facilitates preparation of oxygen-free powders. By a combination of methods we have shown that Ba1xKxFe2As2 obtained via hydride route has the same characteristics as when it is prepared by traditional solid-state synthesis. Refinement from synchrotron powder X-ray diffraction data confirms a linear dependence of unit cell parameters upon K content as well as the tetragonal to orthorhombic transition at low temperatures for compositions with x < 0.2. Magnetic measurements revealed dome-like dependence of superconducting transition temperature Tc upon K content with a maximum of 38 K for x close to 0.4. Electron diffraction and high-resolution high-angle annular dark-field scanning transmission electron microscopy indicates an absence of Ba/K ordering, while local inhomogeneity in the Ba/K distribution takes place at a scale of several angstroms along [110] crystallographic direction. | ||||
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| Publisher | Place of Publication | Washington, D.C. | Editor | ||
| Language | Wos | 000345883900040 | Publication Date | 2014-11-11 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
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| ISSN | 0002-7863;1520-5126; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 13.858 | Times cited | 13 | Open Access | |
| Notes | Approved | Most recent IF: 13.858; 2014 IF: 12.113 | |||
| Call Number | UA @ lucian @ c:irua:121331 | Serial | 1169 | ||
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| Author | Turner, S.; Egoavil, R.; Batuk, M.; Abakumov, A.A.; Hadermann, J.; Verbeeck, J.; Van Tendeloo, G. | ||||
| Title | Site-specific mapping of transition metal oxygen coordination in complex oxides | Type | A1 Journal article | ||
| Year | 2012 | Publication | Applied physics letters | Abbreviated Journal | Appl Phys Lett |
| Volume | 101 | Issue | 24 | Pages | 241910 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract |
We demonstrate site-specific mapping of the oxygen coordination number for transition metals in complex oxides using atomically resolved electron energy-loss spectroscopy in an aberration-corrected scanning transmission electron microscope. Pb2Sr2Bi2Fe6O16 contains iron with a constant Fe3+ valency in both octahedral and tetragonal pyramidal coordination and is selected to demonstrate the principle of site-specific coordination mapping. Analysis of the site-specific Fe-L2,3 data reveals distinct variations in the fine structure that are attributed to Fe in a six-fold (octahedron) or five-fold (distorted tetragonal pyramid) oxygen coordination. Using these variations, atomic resolution coordination maps are generated that are in excellent agreement with simulations. | ||||
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| Publisher | American Institute of Physics | Place of Publication | New York, N.Y. | Editor | |
| Language | Wos | 000312490000035 | Publication Date | 2012-12-12 | |
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0003-6951; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.411 | Times cited | 12 | Open Access | |
| Notes | Fwo; Countatoms; Vortex; Esteem 312483; esteem2jra3 ECASJO; | Approved | Most recent IF: 3.411; 2012 IF: 3.794 | ||
| Call Number | UA @ lucian @ c:irua:105302UA @ admin @ c:irua:105302 | Serial | 3030 | ||
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| 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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| Language | Wos | 000491219600038 | Publication Date | 2019-10-28 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
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| ISSN | 1433-7851 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 11.994 | Times cited | 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 | ||
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| Author | Sheath, B.C.; Xu, X.; Manuel, P.; Hadermann, J.; Batuk, M.; O'Sullivan, J.; Bonilla, R.S.; Clarke, S.J. | ||||
| Title | Structures and magnetic ordering in layered Cr oxide arsenides Sr₂CrO₂Cr₂OAs₂ and Sr₂CrO₃CrAs | Type | A1 Journal article | ||
| Year | 2022 | Publication | Inorganic chemistry | Abbreviated Journal | Inorg Chem |
| Volume | 61 | Issue | 31 | Pages | 10-12385 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract |
Two novel chromium oxide arsenide materials have been synthesized, Sr2CrO2Cr2OAs2 (i.e., Sr2Cr3As2O3) and Sr2CrO3CrAs (i.e., Sr2Cr2AsO3), both of which contain chromium ions in two distinct layers. Sr2CrO2Cr2OAs2 was targeted following electron microscopy measurements on a related phase. It crystallizes in the space group P4/mmm and accommodates distorted CrO4As2 octahedra containing Cr2+ and distorted CrO(2)As(4 )octahedra containing Cr3+. In contrast, Sr2CrO3CrAs incorporates Cr3+ in CrO5 square-pyramidal coordination in [Sr2CrO3](+) layers and Cr2+ ions in CrAs(4 )tetrahedra in [CrAs](-) layers and crystallizes in the space group P4/nmm. Powder neutron diffraction data reveal antiferromagnetic ordering in both compounds. In Sr2CrO3CrAs the Cr2+ moments in the [CrAs](-) layers exhibit long-range ordering, while the Cr3+ moments in the [Sr2CrO3](+) layers only exhibit short-range ordering. However, in Sr2CrO2Cr2OAs2, both the Cr(2+ )moments in the CrO4As2 environments and the Cr3+ moments in the CrO2As4 polyhedra are long-range-ordered below 530(10) K. Above this temperature, only the Cr3+ moments are ordered with a Neel temperature slightly in excess of 600 K. A subtle structural change is evident in Sr2CrO2Cr2OAs2 below the magnetic ordering transitions. | ||||
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| Language | Wos | 000841943600001 | Publication Date | 2022-07-27 | |
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| 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 | Approved | Most recent IF: 4.6 | |||
| Call Number | UA @ admin @ c:irua:190007 | Serial | 7215 | ||
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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 | 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. | ||||
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| Language | Wos | 000610580800001 | Publication Date | 2020-11-10 | |
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| 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 | Sasaki, S.; Giri, S.; Cassidy, S.J.; Dey, S.; Batuk, M.; Vandemeulebroucke, D.; Cibin, G.; Smith, R.I.; Holdship, P.; Grey, C.P.; Hadermann, J.; Clarke, S.J. | ||||
| Title | Anion redox as a means to derive layered manganese oxychalcogenides with exotic intergrowth structures | Type | A1 Journal article | ||
| Year | 2023 | Publication | Nature communications | Abbreviated Journal | |
| Volume | 14 | Issue | 1 | Pages | 2917-11 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract |
Topochemistry enables step-by-step conversions of solid-state materials often leading to metastable structures that retain initial structural motifs. Recent advances in this field revealed many examples where relatively bulky anionic constituents were actively involved in redox reactions during (de)intercalation processes. Such reactions are often accompanied by anion-anion bond formation, which heralds possibilities to design novel structure types disparate from known precursors, in a controlled manner. Here we present the multistep conversion of layered oxychalcogenides Sr(2)MnO(2)Cu(1.5)Ch(2) (Ch=S, Se) into Cu-deintercalated phases where antifluorite type [Cu(1.5)Ch(2)](2.5-) slabs collapsed into two-dimensional arrays of chalcogen dimers. The collapse of the chalcogenide layers on deintercalation led to various stacking types of Sr(2)MnO(2)Ch(2) slabs, which formed polychalcogenide structures unattainable by conventional high-temperature syntheses. Anion-redox topochemistry is demonstrated to be of interest not only for electrochemical applications but also as a means to design complex layered architectures. Low temperature chemical transformations of solids using high-energy intermediates have enabled the synthesis of a new series of layered oxide chalcogenide containing oxidised chalcogenide dimers promising a new range of solids. | ||||
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| Language | Wos | 001024186000011 | Publication Date | 2023-05-22 | |
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| ISSN | 2041-1723 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 16.6 | Times cited | Open Access | OpenAccess | |
| Notes | Approved | Most recent IF: 16.6; 2023 IF: 12.124 | |||
| Call Number | UA @ admin @ c:irua:199281 | Serial | 8832 | ||
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| Author | Kutukov, P.; Rumyantseva, M.; Krivetskiy, V.; Filatova, D.; Batuk, M.; Hadermann, J.; Khmelevsky, N.; Aksenenko, A.; Gaskov, A. | ||||
| Title | Influence of Mono- and Bimetallic PtOx, PdOx, PtPdOx Clusters on CO Sensing by SnO2 Based Gas Sensors | Type | A1 Journal Article | ||
| Year | 2018 | Publication | Nanomaterials | Abbreviated Journal | Nanomaterials-Basel |
| Volume | 8 | Issue | 11 | Pages | 917 |
| Keywords | A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; | ||||
| Abstract |
To obtain a nanocrystalline SnO2 matrix and mono- and bimetallic nanocomposites SnO2/Pd, SnO2/Pt, and SnO2/PtPd, a flame spray pyrolysis with subsequent impregnation was used. The materials were characterized using X-ray diffraction (XRD), a single-point BET method, transmission electron microscopy (TEM), and high angle annular dark field scanning transmission electron microscopy (HAADF-STEM) with energy dispersive X-ray (EDX) mapping. The electronic state of the metals in mono- and bimetallic clusters was determined using X-ray photoelectron spectroscopy (XPS). The active surface sites were investigated using the Fourier Transform infrared spectroscopy (FTIR) and thermo-programmed reduction with hydrogen (TPR-H-2) methods. The sensor response of blank SnO2 and nanocomposites had a carbon monoxide (CO) level of 6.7 ppm and was determined in the temperature range 60-300 degrees C in dry (Relative Humidity (RH) = 0%) and humid (RH = 20%) air. The sensor properties of the mono- and bimetallic nanocomposites were analyzed on the basis of information on the electronic state, the distribution of modifiers in SnO2 matrix, and active surface centers. For SnO2/PtPd, the combined effect of the modifiers on the electrophysical properties of SnO2 explained the inversion of sensor response from n- to p-types observed in dry conditions. | ||||
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| Language | Wos | 000451316100052 | Publication Date | 2018-11-07 | |
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| ISSN | 2079-4991 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.553 | Times cited | 7 | Open Access | Not_Open_Access |
| Notes | This research was funded by the Russian Ministry of Education and Sciences (Agreement No. 14.613.21.0075, RFMEFI61317X0075). | Approved | Most recent IF: 3.553 | ||
| Call Number | EMAT @ emat @c:irua:155767 | Serial | 5139 | ||
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| Author | Vermang, B.; Brammertz, G.; Meuris, M.; Schnabel, T.; Ahlswede, E.; Choubrac, L.; Harel, S.; Cardinaud, C.; Arzel, L.; Barreau, N.; van Deelen, J.; Bolt, P.-J.; Bras, P.; Ren, Y.; Jaremalm, E.; Khelifi, S.; Yang, S.; Lauwaert, J.; Batuk, M.; Hadermann, J.; Kozina, X.; Handick, E.; Hartmann, C.; Gerlach, D.; Matsuda, A.; Ueda, S.; Chikyow, T.; Felix, R.; Zhang, Y.; Wilks, R.G.; Baer, M. | ||||
| Title | Wide band gap kesterite absorbers for thin film solar cells: potential and challenges for their deployment in tandem devices | Type | A1 Journal article | ||
| Year | 2019 | Publication | Sustainable Energy & Fuels | Abbreviated Journal | |
| Volume | 3 | Issue | 9 | Pages | 2246-2259 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract |
This work reports on developments in the field of wide band gap Cu2ZnXY4 (with X = Sn, Si or Ge, and Y = S, Se) kesterite thin film solar cells. An overview on recent developments and the current understanding of wide band gap kesterite absorber layers, alternative buffer layers, and suitable transparent back contacts is presented. Cu2ZnGe(S,Se)(4) absorbers with absorber band gaps up to 1.7 eV have been successfully developed and integrated into solar cells. Combining a CdS buffer layer prepared by an optimized chemical bath deposition process with a 1.36 eV band gap absorber resulted in a record Cu2ZnGeSe4 cell efficiency of 7.6%, while the highest open-circuit voltage of 730 mV could be obtained for a 1.54 eV band gap absorber and a Zn(O,S) buffer layer. Employing InZnOx or TiO2 protective top layers on SnO2:In transparent back contacts yields 85-90% of the solar cell performance of reference cells (with Mo back contact). These advances show the potential as well as the challenges of wide band gap kesterites for future applications in high-efficiency and low-cost tandem photovoltaic devices. | ||||
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| Language | Wos | 000482057500004 | Publication Date | 2019-06-14 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
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| ISSN | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | ||
| Impact Factor | Times cited | 2 | Open Access | ||
| Notes | ; This project has received funding from the European Union's Horizon 2020 Research and Innovation Program under grant agreement No. 640868. The synchrotron radiation experiments were performed at the SPring-8 beamline BL15XU with the approval of the NIMS Synchrotron X-ray Station (Proposals 2016A4600, 2016B4601, and 2017A4600) and at BESSY II with the approval of HZB. B. Vermang has received funding from the European Research Council (ERC) under the European Union's Horizon 2020 Research and Innovation Programme (grant agreement no. 715027). ; | Approved | Most recent IF: NA | ||
| Call Number | UA @ admin @ c:irua:161785 | Serial | 5404 | ||
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| Author | Garud, S.; Gampa, N.; Allen, T.G.; Kotipalli, R.; Flandre, D.; Batuk, M.; Hadermann, J.; Meuris, M.; Poortmans, J.; Smets, A.; Vermang, B. | ||||
| Title | Surface passivation of CIGS solar cells using gallium oxide | Type | A1 Journal article | ||
| Year | 2018 | Publication | Physica status solidi : A : applications and materials science | Abbreviated Journal | Phys Status Solidi A |
| Volume | 215 | Issue | 7 | Pages | 1700826 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract |
This work proposes gallium oxide grown by plasma-enhanced atomic layer deposition, as a surface passivation material at the CdS buffer interface of Cu(In,Ga)Se-2 (CIGS) solar cells. In preliminary experiments, a metal-insulator-semiconductor (MIS) structure is used to compare aluminium oxide, gallium oxide, and hafnium oxide as passivation layers at the CIGS-CdS interface. The findings suggest that gallium oxide on CIGS may show a density of positive charges and qualitatively, the least interface trap density. Subsequent solar cell results with an estimated 0.5nm passivation layer show an substantial absolute improvement of 56mV in open-circuit voltage (V-OC), 1mAcm(-2) in short-circuit current density (J(SC)), and 2.6% in overall efficiency as compared to a reference (with the reference showing 8.5% under AM 1.5G). | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000430128500015 | Publication Date | 2018-02-27 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1862-6300 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 1.775 | Times cited | 8 | Open Access | Not_Open_Access |
| Notes | ; The work published in this paper was supported by the European Research Council (ERC) under the Union's Horizon 2020 research and innovation programme (grant agreement No 715027). The authors would also like to thank Dr. Marcel Simor (Solliance) for the CIGS layer fabrication and Prof. Johan Lauwaert (Universtiy of Ghent) for his guidance on DLTS measurements. ; | Approved | Most recent IF: 1.775 | ||
| Call Number | UA @ lucian @ c:irua:150761 | Serial | 4981 | ||
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| Author | Buffière, M.; Brammertz, G.; Batuk, M.; Verbist, C.; Mangin, D.; Koble, C.; Hadermann, J.; Meuris, M.; Poortmans, J. | ||||
| Title | Microstructural analysis of 9.7% efficient Cu2ZnSnSe4 thin film solar cells | Type | A1 Journal article | ||
| Year | 2014 | Publication | Applied physics letters | Abbreviated Journal | Appl Phys Lett |
| Volume | 105 | Issue | 18 | Pages | 183903 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract |
This work presents a detailed analysis of the microstructure and the composition of our record Cu 2ZnSnSe4 (CZTSe)-CdS-ZnO solar cell with a total area efficiency of 9.7%. The average composition of the CZTSe crystallites is Cu 1.94 Zn 1.12Sn0.95Se3.99. Large crystals of ZnSe secondary phase (up to 400 nm diameter) are observed at the voids between the absorber and the back contact, while smaller ZnSe domains are segregated at the grain boundaries and close to the surface of the CZTSe grains. An underlying layer and some particles of Cu xSe are observed at the Mo-MoSe2-Cu2ZnSnSe4 interface. The free surface of the voids at the back interface is covered by an amorphous layer containing Cu, S, O, and C, while the presence of Cd, Na, and K is also observed in this region. | ||||
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| Publisher | American Institute of Physics | Place of Publication | New York, N.Y. | Editor | |
| Language | Wos | 000345000000086 | Publication Date | 2014-11-08 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0003-6951;1077-3118; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.411 | Times cited | 17 | Open Access | |
| Notes | Approved | Most recent IF: 3.411; 2014 IF: 3.302 | |||
| Call Number | UA @ lucian @ c:irua:121329 | Serial | 2038 | ||
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| Author | 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. | ||||
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| 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 | 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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| Publisher | Place of Publication | Editor | |||
| 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 | Cassidy, S.J.; Batuk, M.; Batuk, D.; Hadermann, J.; Woodruff, D.N.; Thompson, A.L.; Clarke, S.J. | ||||
| Title | Complex Microstructure and Magnetism in Polymorphic CaFeSeO | Type | A1 Journal article | ||
| Year | 2016 | Publication | Inorganic chemistry | Abbreviated Journal | Inorg Chem |
| Volume | 55 | Issue | 55 | Pages | 10714-10726 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract |
The structural complexity of the antiferromagnetic oxide selenide CaFeSeO is described. The compound contains puckered FeSeO layers composed of FeSe2O2 tetrahedra sharing all their vertexes. Two polymorphs coexist that can be derived from an archetype BaZnSO structure by cooperative tilting of the FeSe2O2 tetrahedra. The polymorphs differ in the relative arrangement of the puckered layers of vertex-linked FeSe2O2 tetrahedra. In a noncentrosymmetric Cmc21 polymorph (a = 3.89684(2) A, b = 13.22054(8) A, c = 5.93625(2) A) the layers are related by the C-centering translation, while in a centrosymmetric Pmcn polymorph, with a similar cell metric (a = 3.89557(6) A, b = 13.2237(6) A, c = 5.9363(3) A), the layers are related by inversion. The compound shows long-range antiferromagnetic order below a Neel temperature of 159(1) K with both polymorphs showing antiferromagnetic coupling via Fe-O-Fe linkages and ferromagnetic coupling via Fe-Se-Fe linkages within the FeSeO layers. The magnetic susceptibility also shows evidence for weak ferromagnetism which is modeled in the refinements of the magnetic structure as arising from an uncompensated spin canting in the noncentrosymmetric polymorph. There is also a spin glass component to the magnetism which likely arises from the disordered regions of the structure evident in the transmission electron microscopy. | ||||
| Address | Department of Chemistry, Inorganic Chemistry Laboratory, University of Oxford , South Parks Road, Oxford OX1 3QR, United Kingdom | ||||
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| Language | English | Wos | 000385785700085 | Publication Date | 2016-10-05 |
| 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 | Buffière, M.; Brammertz, G.; Sahayaraj, S.; Batuk, M.; Khelifi, S.; Mangin, D.; El Mel, A.A.; Arzel, L.; Hadermann, J.; Meuris, M.; Poortmans, J.; | ||||
| Title | KCN chemical etch for interface engineering in Cu2ZnSnSe4 solar cells | Type | A1 Journal article | ||
| Year | 2015 | Publication | ACS applied materials and interfaces | Abbreviated Journal | Acs Appl Mater Inter |
| Volume | 7 | Issue | 7 | Pages | 14690-14698 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract |
The removal of secondary phases from the surface of the kesterite crystals is one of the major challenges to improve the performances of Cu2ZnSn(S,Se)(4) (CZTSSe) thin film solar cells. In this Contribution, the KCN/KOH Chemical etching approach, originally developed for the removal of CuxSe phases in Cu(In,Ga)(S,Se)(2) thin films) is applied to CZTSe absorbers exhibiting various chemical compositions. Two distinct electrical behaviors were observed on CZTSe/CdS solar cells after treatment: (i) the improvement of the fill factor (FF) after 30 s of etching for the CZTSe absorbers showing initially a distortion of the electrical characteristic; (ii) the progressive degradation Of the FF after long treatment time for all Cu-poor CZTSe solar cell samples. The first effect can be attributed to the action of KCN on the absorber, that is found to clean the absorber free surface from most of the secondary phases surrounding the kesterite grains (e.g., Se-0, CuxSe, SnSex, SnO2, Cu2SnSe3 phases, excepting the ZnSe-based phases). The second observation was identified as a consequence of the preferential etching of Se, Sn, and Zn from the CZTSe surface by the KOH solution, combined with the modification of the alkali content of the absorber. The formation of a Cu-rich shell at the absorber/buffer layer interface, leading to the increase of the recombination rate at the interface, and the increase in the doping of the absorber layer after etching are found to be at the origin of the deterioration of the FF of the solar cells. | ||||
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| Language | Wos | 000358395200019 | Publication Date | 2015-06-03 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1944-8244;1944-8252; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 7.504 | Times cited | 34 | Open Access | |
| Notes | Approved | Most recent IF: 7.504; 2015 IF: 6.723 | |||
| Call Number | c:irua:127153 | Serial | 1755 | ||
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| Author | Guzzinati, G.; Altantzis, T.; Batuk, M.; De Backer, A.; Lumbeeck, G.; Samaee, V.; Batuk, D.; Idrissi, H.; Hadermann, J.; Van Aert, S.; Schryvers, D.; Verbeeck, J.; Bals, S. | ||||
| Title | Recent Advances in Transmission Electron Microscopy for Materials Science at the EMAT Lab of the University of Antwerp | Type | A1 Journal article | ||
| Year | 2018 | Publication | Materials | Abbreviated Journal | Materials |
| Volume | 11 | Issue | 11 | Pages | 1304 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract |
The rapid progress in materials science that enables the design of materials down to the nanoscale also demands characterization techniques able to analyze the materials down to the same scale, such as transmission electron microscopy. As Belgium’s foremost electron microscopy group, among the largest in the world, EMAT is continuously contributing to the development of TEM techniques, such as high-resolution imaging, diffraction, electron tomography, and spectroscopies, with an emphasis on quantification and reproducibility, as well as employing TEM methodology at the highest level to solve real-world materials science problems. The lab’s recent contributions are presented here together with specific case studies in order to highlight the usefulness of TEM to the advancement of materials science. | ||||
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| Language | Wos | 000444112800041 | Publication Date | 2018-07-28 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
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| ISSN | 1996-1944 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.654 | Times cited | 15 | Open Access | OpenAccess |
| Notes | Fonds Wetenschappelijk Onderzoek, G.0502.18N, G.0267.18N, G.0120.12N, G.0365.15N, G.0934.17N, S.0100.18N AUHA13009 ; European Research Council, COLOURATOM 335078 ; Universiteit Antwerpen, GOA Solarpaint ; G. Guzzinati, T. Altantzis and A. De Backer have been supported by postdoctoral fellowship grants from the Research Foundation Flanders (FWO). Funding was also received from the European Research Council (starting grant no. COLOURATOM 335078), the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement no. 770887), the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0502.18N, G.0267.18N, G.0120.12N, G.0365.15N, G.0934.17N, S.0100.18N, G.0401.16N) and from the University of Antwerp through GOA project Solarpaint. Funding for the TopSPIN precession system under grant AUHA13009, as well as for the Qu-Ant-EM microscope, is acknowledged from the HERCULES Foundation. H. Idrissi is mandated by the Belgian National Fund for Scientific Research (F.R.S.-FNRS). (ROMEO:green; preprint:; postprint:can ; pdfversion:can); saraecas; ECAS_Sara; | Approved | Most recent IF: 2.654 | ||
| Call Number | EMAT @ emat @c:irua:153737UA @ admin @ c:irua:153737 | Serial | 5064 | ||
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| Author | Bhaskar, G.; Gvozdetskyi, V.; Batuk, M.; Wiaderek, K.M.; Sun, Y.; Wang, R.; Zhang, C.; Carnahan, S.L.; Wu, X.; Ribeiro, R.A.; Bud'ko, S.L.; Canfield, P.C.; Huang, W.; Rossini, A.J.; Wang, C.-Z.; Ho, K.-M.; Hadermann, J.; Zaikina, J., V | ||||
| Title | Topochemical deintercalation of Li from layered LiNiB : toward 2D MBene | Type | A1 Journal article | ||
| Year | 2021 | Publication | Journal Of The American Chemical Society | Abbreviated Journal | J Am Chem Soc |
| Volume | 143 | Issue | 11 | Pages | 4213-4223 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract |
The pursuit of two-dimensional (2D) borides, MBenes, has proven to be challenging, not the least because of the lack of a suitable precursor prone to the deintercalation. Here, we studied room-temperature topochemical deintercalation of lithium from the layered polymorphs of the LiNiB compound with a considerable amount of Li stored in between [NiB] layers (33 at. % Li). Deintercalation of Li leads to novel metastable borides (Li similar to 0.5NiB) with unique crystal structures. Partial removal of Li is accomplished by exposing the parent phases to air, water, or dilute HCl under ambient conditions. Scanning transmission electron microscopy and solid-state Li-7 and B-1(1) NMR spectroscopy, combined with X-ray pair distribution function (PDF) analysis and DFT calculations, were utilized to elucidate the novel structures of (Li similar to 0.5NiB) and the mechanism of Li-deintercalation. We have shown that the deintercalation of Li proceeds via a “zip-lock” mechanism, leading to the condensation of single [NiB] layers into double or triple layers bound via covalent bonds, resulting in structural fragments with Li[NiB](2) and Li[NiB](3) compositions. The crystal structure of Li similar to 0.5NiB is best described as an intergrowth of the ordered single [NiB], double [NiB](2), or triple [NiB](3) layers alternating with single Li layers; this explains its structural complexity. The formation of double or triple [NiB] layers induces a change in the magnetic behavior from temperature-independent paramagnets in the parent LiNiB compounds to the spin-glassiness in the deintercalated Li similar to 0.5NiB counterparts. LiNiB compounds showcase the potential to access a plethora of unique materials, including 2D MBenes (NiB). | ||||
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| Language | Wos | 000634761500021 | Publication Date | 2021-03-15 | |
| 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 | 13.858 | Times cited | Open Access | Not_Open_Access | |
| Notes | Approved | Most recent IF: 13.858 | |||
| Call Number | UA @ admin @ c:irua:177697 | Serial | 6790 | ||
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| Author | Batuk, M.; Batuk, D.; Tsirlin, A.A.; Rozova, M.G.; Antipov, E.V.; Hadermann, J.; Van Tendeloo, G. | ||||
| Title | Homologous series of layered perovskites An+1BnO3n-1Cl : crystal and magnetic structure of a new oxychloride Pb4BiFe4O11Cl | Type | A1 Journal article | ||
| Year | 2013 | Publication | Inorganic chemistry | Abbreviated Journal | Inorg Chem |
| Volume | 52 | Issue | 4 | Pages | 2208-2218 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract |
The nuclear and magnetic structure of a novel oxychloride Pb4BiFe4O11Cl has been studied over the temperature range 1.5700 K using a combination of transmission electron microscopy and synchrotron and neutron powder diffraction [space group P4/mbm, a = 5.5311(1) Å, c = 19.586(1) Å, T = 300 K]. Pb4BiFe4O11Cl is built of truncated (Pb,Bi)3Fe4O11 quadruple perovskite blocks separated by CsCl-type (Pb,Bi)2Cl slabs. The perovskite blocks consist of two layers of FeO6 octahedra located between two layers of FeO5 tetragonal pyramids. The FeO6 octahedra rotate about the c axis, resulting in a √2ap × √2ap × c superstructure. Below TN = 595(17) K, Pb4BiFe4O11Cl adopts a G-type antiferromagnetic structure with the iron magnetic moments confined to the ab plane. The ordered magnetic moments at 1.5 K are 3.93(3) and 3.62(4) μB on the octahedral and square-pyramidal iron sites, respectively. Pb4BiFe4O11Cl can be considered a member of the perovskite-based An+1BnO3n1Cl homologous series (A = Pb/Bi; B = Fe) with n = 4. The formation of a subsequent member of the series with n = 5 is also demonstrated. | ||||
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| Publisher | Place of Publication | Easton, Pa | Editor | ||
| Language | Wos | 000315255200067 | Publication Date | 2013-02-05 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0020-1669;1520-510X; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 4.857 | Times cited | 6 | Open Access | |
| Notes | Countatoms | Approved | Most recent IF: 4.857; 2013 IF: 4.794 | ||
| Call Number | UA @ lucian @ c:irua:106185 | Serial | 1486 | ||
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| Author | Zhang, F.; Vanmeensel, K.; Inokoshi, M.; Batuk, M.; Hadermann, J.; Van Meerbeek, B.; Naert, I.; Vleugels, J. | ||||
| Title | Critical influence of alumina content on the low temperature degradation of 2-3 mol% yttria-stabilized TZP for dental restorations | Type | A1 Journal article | ||
| Year | 2015 | Publication | Journal of the European Ceramic Society | Abbreviated Journal | J Eur Ceram Soc |
| Volume | 35 | Issue | 35 | Pages | 741-750 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract |
The influence of 0.25, 2 and 5 wt.% alumina addition on the mechanical properties and low temperature degradation (LTD) of 3, 2.5 and 2 mol% yttria-stabilized TZP ceramics was investigated. The amount of alumina addition was observed to have a crucial impact on the degradation of Y-TZP ceramics. Independent on the yttria stabilizer content, 0.25 wt.% alumina had a higher degradation retarding effect to Y-TZP ceramics than 2 and 5 wt.% of alumina addition, which had a comparable effect. The apparent activation energy for the degradation process was increased by adding alumina, but it was the same for 0.255 wt.% alumina doped 3Y-TZP ceramics. For Y-TZPs containing a small amount of alumina addition, only the segregated Al3+ at the grain boundaries of the zirconia grains was effective to retard the degradation of Y-TZPs. The secondary phase Al2O3 grains increased the degradation kinetics, which might be attributed to the residual stresses. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Barking | Editor | ||
| Language | Wos | 000345201700032 | Publication Date | 2014-09-27 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0955-2219; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.411 | Times cited | 37 | Open Access | |
| Notes | Fwo G043110n | Approved | Most recent IF: 3.411; 2015 IF: 2.947 | ||
| Call Number | c:irua:121328 | Serial | 544 | ||
| Permanent link to this record | |||||
| Author | Zhang, F.; Batuk, M.; Hadermann, J.; Manfredi, G.; Mariën, A.; Vanmeensel, K.; Inokoshi, M.; Van Meerbeek, B.; Naert, I.; Vleugels, J. | ||||
| Title | Effect of cation dopant radius on the hydrothermal stability of tetragonal zirconia: Grain boundary segregation and oxygen vacancy annihilation | Type | A1 Journal article | ||
| Year | 2016 | Publication | Acta materialia | Abbreviated Journal | Acta Mater |
| Volume | 106 | Issue | 106 | Pages | 48-58 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract |
The hydrothermal aging stability of 3Y-TZP-xM2O3 (M = La, Nd, Sc) was investigated as a function of 0.02–5 mol% M2O3 dopant content and correlated to the overall phase content, t-ZrO2 lattice parameters, grain size distribution, grain boundary chemistry and ionic conductivity. The increased aging stability with increasing Sc2O3 content and the optimum content of 0.4–0.6 mol% Nd2O3 or 0.2–0.4 mol% La2O3, resulting in the highest aging resistance, could be directly related to the constituent phases and the lattice parameters of the remaining tetragonal zirconia. At low M2O3 dopant contents ≤0.4 mol%, the different aging behavior of tetragonal zirconia was attributed to the defect structure of the zirconia grain boundary which was influenced by the dopant cation radius. It was observed that the grain boundary ionic resistivity and the aging resistance followed the same trend: La3+ > Nd3+ > Al3+ > Sc3+, proving that hydrothermal aging is driven by the diffusion of water-derived mobile species through the oxygen vacancies. Accordingly, we elucidated the underlying mechanism by which a larger trivalent cation segregating at the zirconia grain boundary resulted in a higher aging resistance. |
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| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000371650300006 | Publication Date | 2016-01-08 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1359-6454 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 5.301 | Times cited | 37 | Open Access | |
| Notes | The authors acknowledge the Research Fund of KU Leuven under project 0T/10/052 and the Fund for Scientific Research Flanders (FWO-Vlaanderen) under grant G.0431.10N. F. Zhang thanks the Research Fund of KU Leuven for her post-doctoral fellowship (PDM/15/153). | Approved | Most recent IF: 5.301 | ||
| Call Number | c:irua:132435 | Serial | 4076 | ||
| Permanent link to this record | |||||
| Author | Chizhov, As.; Rumyantseva, Mn.; Drozdov, Ka.; Krylov, Iv.; Batuk, M.; Hadermann, J.; Filatova, Dg.; Khmelevsky, No.; Kozlovsky, Vf.; Maltseva, Ln.; Gaskov, Am. | ||||
| Title | Photoresistive gas sensor based on nanocrystalline ZnO sensitized with colloidal perovskite CsPbBr3 nanocrystals | Type | A1 Journal article | ||
| Year | 2021 | Publication | Sensors And Actuators B-Chemical | Abbreviated Journal | Sensor Actuat B-Chem |
| Volume | 329 | Issue | Pages | 129035 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract |
The development of sensor materials of which gas sensitivity activates under light illumination is of great importance for the design of portable gas analyzers with low power consumption. In the present work a ZnO/CsPbBr3 nanocomposite based on nanocrystalline ZnO and colloidal cubic-shaped perovskite CsPbBr3 nanocrystals (NCs) capped by oleic acide and oleylamine was synthesized. The individual materials and obtained nanocomposite are characterized by x-ray diffraction, low-temperature nitrogen adsorption, x-ray photoelectron spectroscopy, high angle annular dark field scanning transmission electron microscopy with energy-dispersive Xray spectroscopy mapping and UV-vis absorption spectroscopy. The spectral dependence of the photoconductivity of the ZnO/CsPbBr3 nanocomposite reveals a well-defined peak that strongly correlates with the its optical absorption spectrum. The nanocomposite ZnO/CsPbBr3 shows enhanced photoresponse under visible light illumination (lambda(max) = 470 nm, 8 mW/cm(2)) in air, oxygen and argone, compared with pure nanocrystalline ZnO. Under periodic illumination in the temperature range of 25-100 degrees C, the ZnO/CsPbBr3 nanocomposite shows a sensor response to 0.5-3.0 ppm NO2, unlike pure nanocrystalline ZnO matrix, which demonstrates sensor sensitivity to NO2 under the same conditions above 100 degrees C. The effects of humidity on the sensor signal and photoresponse are also discussed. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000612060700009 | Publication Date | 2020-10-25 | |
| 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 | OpenAccess | |
| Notes | The reported study was funded by RFBR according to the research project N◦ 18-33-01004 and in part by a grant from the St. Petersburg State University – Event 3-2018 (id: 46380300). Element mapping for sensors were supported by M.V. Lomonosov Moscow State University Program of Development (X-ray fluorescence spectrometer Tornado M4 plus). | Approved | Most recent IF: 5.401 | ||
| Call Number | EMAT @ emat @c:irua:176123 | Serial | 6707 | ||
| Permanent link to this record | |||||
| Author | Batuk, D.; Batuk, M.; Tsirlin, A.A.; Hadermann, J.; Abakumov, A.M. | ||||
| Title | Trapping of Oxygen Vacancies at Crystallographic Shear Planes in Acceptor-Doped Pb-Based Ferroelectrics | Type | A1 Journal article | ||
| Year | 2015 | Publication | Angewandte Chemie: international edition in English | Abbreviated Journal | Angew Chem Int Edit |
| Volume | 54 | Issue | 54 | Pages | 14787-14790 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract |
The defect chemistry of the ferroelectric material PbTiO3 after doping with Fe(III) acceptor ions is reported. Using advanced transmission electron microscopy and powder X-ray and neutron diffraction, we demonstrate that even at concentrations as low as circa 1.7% (material composition approximately ABO2.95), the oxygen vacancies are trapped into extended planar defects, specifically crystallographic shear planes. We investigate the evolution of these defects upon doping and unravel their detailed atomic structure using the formalism of superspace crystallography, thus unveiling their role in nonstoichiometry in the Pb-based perovskites. | ||||
| Address | Chemistry Department, Moscow State University, 119991, Moscow (Russia). artem.abakumov@uantwerpen.be | ||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | English | Wos | 000367723400031 | Publication Date | 2015-10-21 |
| 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 | 3 | Open Access | |
| Notes | A.M.A. is grateful to the Russian Science Foundation (grant 14-13-00680). AT was funded by the Mobilitas grant MTT77 of the ESF and by the Federal Ministry for Education and Research through the Sofja Kovalevskaya Award of Alexander von Humboldt Foundation. | Approved | Most recent IF: 11.994; 2015 IF: 11.261 | ||
| Call Number | c:irua:131104 | Serial | 4080 | ||
| Permanent link to this record | |||||
| Author | Batuk, D.; Batuk, M.; Abakumov, A.M.; Hadermann, J. | ||||
| Title | Synergy between transmission electron microscopy and powder diffraction : application to modulated structures | Type | A1 Journal article | ||
| Year | 2015 | Publication | Acta crystallographica: section B: structural science | Abbreviated Journal | Acta Crystallogr B |
| Volume | 71 | Issue | 71 | Pages | 127-143 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract |
The crystal structure solution of modulated compounds is often very challenging, even using the well established methodology of single-crystal X-ray crystallography. This task becomes even more difficult for materials that cannot be prepared in a single-crystal form, so that only polycrystalline powders are available. This paper illustrates that the combined application of transmission electron microscopy (TEM) and powder diffraction is a possible solution to the problem. Using examples of anion-deficient perovskites modulated by periodic crystallographic shear planes, it is demonstrated what kind of local structural information can be obtained using various TEM techniques and how this information can be implemented in the crystal structure refinement against the powder diffraction data. The following TEM methods are discussed: electron diffraction (selected area electron diffraction, precession electron diffraction), imaging (conventional high-resolution TEM imaging, high-angle annular dark-field and annular bright-field scanning transmission electron microscopy) and state-of-the-art spectroscopic techniques (atomic resolution mapping using energy-dispersive X-ray analysis and electron energy loss spectroscopy). | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Copenhagen | Editor | ||
| Language | Wos | 000352166500002 | Publication Date | 2015-04-01 | |
| 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 | 11 | Open Access | |
| Notes | Fwo G039211n | Approved | Most recent IF: 2.032; 2015 IF: NA | ||
| Call Number | c:irua:124411 | Serial | 3408 | ||
| Permanent link to this record | |||||
| Author | Morozov, V.A.; Batuk, D.; Batuk, M.; Basovich, O.M.; Khaikina, E.G.; Deyneko, D.V.; Lazoryak, B.I.; Leonidov, I.I.; Abakumov, A.M.; Hadermann, J. | ||||
| Title | Luminescence Property Upgrading via the Structure and Cation Changing in AgxEu(2–x)/3WO4and AgxGd(2–x)/3–0.3Eu0.3WO4 | Type | A1 Journal article | ||
| Year | 2017 | Publication | Chemistry of materials | Abbreviated Journal | Chem Mater |
| Volume | 29 | Issue | 20 | Pages | 8811-8823 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract |
The creation and ordering of A-cation vacancies and the effect of cation substitutions in the scheelite-type framework are investigated as a factor for controlling the scheelite-type structure and luminescence properties. AgxEu3+(2−x)/3□(1−2x)/3WO4 and AgxGd(2−x)/3−0.3Eu3+0.3□(1−2x)/3WO4 (x = 0.5−0) scheelite-type phases were synthesized by a solid state method, and their structures were investigated using a combination of transmission electron microscopy techniques and powder synchrotron X-ray diffraction. Transmission electron microscopy also revealed the (3 + 1)D incommensurately modulated character of AgxEu3+(2−x)/3□(1−2x)/3WO4 (x = 0.286, 0.2) phases. The crystal structures of the scheelite-based AgxEu3+(2−x)/3□(1−2x)/3WO4 (x = 0.5, 0.286, 0.2) red phosphors have been refined from high resolution synchrotron powder X-ray diffraction data. The luminescence properties of all phases under near-ultraviolet (n-UV) light have been investigated. The excitation spectra of AgxEu3+(2−x)/3□(1−2x)/3WO4 (x = 0.5, 0.286,0.2) phosphors show the strongest absorption at 395 nm, which matches well with the commercially available n-UV-emitting GaN-based LED chip. The excitation spectra of the Eu2/3□1/3WO4 and Gd0.367Eu0.30□1/3WO4 phases exhibit the highest contribution of the charge transfer band at 250 nm and thus the most efficient energy transfer mechanism between the host and the luminescent ion as compared to direct excitation. The emission spectra of all samples indicate an intense red emission due to the 5D0 → 7F2 transition of Eu3+. Concentration dependence of the 5D0 → 7F2 emission for AgxEu(2−x)/3□(1−2x)/3WO4 samples differs from the same dependence for the earlier studied NaxEu3+(2−x)/3□(1−2x)/3MoO4 (0 ≤ x ≤ 0.5) phases. The intensity of the 5D0 → 7F2 emission is reduced almost 7 times with decreasing x from 0.5 to 0, but it practically does not change in the range from x = 0.286 to x = 0.200. The emission spectra of Gd-containing samples show a completely different trend as compared to only Eu-containing samples. The Eu3+ emission under excitation of Eu3+(5L6) level (λex = 395 nm) increases more than 2.5 times with the increasing Gd3+ concentration from 0.2 (x = 0.5) to 0.3 (x = 0.2) in the AgxGd(2−x)/3−0.3Eu3+0.3□(1−2x)/3WO4, after which it remains almost constant for higher Gd3+ concentrations. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000413884900028 | Publication Date | 2017-10-24 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0897-4756 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 9.466 | Times cited | 7 | Open Access | Not_Open_Access |
| Notes | This research was supported by FWO (project G039211N), Flanders Research Foundation. V.A.M. is grateful for financial support of the Russian Foundation for Basic Research (Grant 15-03-07741). E.G.K. and O.M.B. are grateful for financial support of the Russian Foundation for Basic Research (Grants 13-03-01020 and 16-03-00510). D.V.D. is grateful for financial support of the Russian Foundation for Basic Research (Grant 16-33-00197) and the Foundation of the President of the Russian Federation (Grant MK-7926.2016.5.). We are grateful to the ESRF for granting the beamtime. Experimental support of Andy Fitch at the ID31 beamline of ESRF is kindly acknowledged. | Approved | Most recent IF: 9.466 | ||
| Call Number | EMAT @ emat @c:irua:147241 | Serial | 4768 | ||
| Permanent link to this record | |||||
| Author | Batuk, D.; Batuk, M.; Morozov, V.A.; Meert, K.W.; Smet, P.F.; Poelman, D.; Abakumov, A.M.; Hadermann, J. | ||||
| Title | Effect of cation vacancies on the crystal structure and luminescent properties of Ca(0.85-1.5x)Gd(x)Eu(0.1)_(0.05+0.5x)WO(4) (0<x<0.567) scheelite-based red phosphors | Type | A1 Journal article | ||
| Year | 2017 | Publication | Journal of alloys and compounds | Abbreviated Journal | J Alloy Compd |
| Volume | 706 | Issue | 706 | Pages | 358-369 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract |
The Ca0.85-1.5xGdxEu0.1_0.05-0.5xWO4 (0 < x < 0.567) series of cation-deficient scheelites is investigated to unveil the influence of the cation vacancies on the crystal structure and luminescent properties. The concentration of the vacancies is varied by the heterovalent substitution of Gd3+ for Ca2+, keeping the concentration of the Eu3+ luminescent centers constant in all compounds of the series. The crystal structure of the materials is studied using a combination of transmission electron microscopy and synchrotron X-ray powder diffraction. At low vacancy concentration (x = 0.1, 0.2), cations and cation vacancies are randomly distributed in the structure, and the materials preserve the I41/a symmetry of the parent scheelite structure [x = 0.1: a = 5.25151(1) Å, c = 11.39479(2) Å; x = 0.2: a = 5.25042(1) Å, c = 11.41335(2) Å]. At higher concentration, the cation-vacancy ordering gives rise to incommensurately modulated structures. The x = 0.3 structure has a (3 + 2)D tetragonal symmetry [superspace group I41/a(a,b,0)00(-b,a,0)00, a = 5.24700(1) Å, c = 11.45514(3) Å, q1 = 0.51637(14)a* + 0.80761(13)b*, q2 = -0.80761a* + 0.51637b*]. At x = 0.4, the scheelite basic cell undergoes a monoclinic distortion with the formation of the (3 + 1)D structure [superspace group I2/b(a,b,0)00, a = 5.23757(1) Å, b = 5.25035(1) Å, c = 11.45750(2) Å, g = 90.5120(2) o, q = 0.54206(8)a* + 0.79330(8)b*]. In both structures, the antiphase Ca and (Gd,Eu) occupancy modulations indicate that the ordering between the A cations and vacancies also induces partial Ca/(Gd,Eu) cation ordering. Further increase of the Gd3þ content up to x = 0.567 leads to the formation of a monoclinic phase (space group C2/c) with the Eu2/3WO4-type structure. Despite the difference in the cation-vacancy ordering patterns, all materials in the series demonstrate very similar quantum efficiency and luminescence decay lifetimes. However, the difference in the local coordination environment of the A cation species noticeably affects the line width and the multiplet splitting of the 4f6-4f6 transitions. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000397997300045 | Publication Date | 2017-02-16 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0925-8388 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.133 | Times cited | 2 | Open Access | OpenAccess |
| Notes | This research was supported by FWO (Flanders Research Foundation, project G039211N). V.A.M. is grateful for financial support of the Russian Foundation for Basic Research (Grant 15-03-07741).We are grateful to the ESRF for granting the beamtime at the ID22 beamline and to Andy Fitch for the support during the experiment. | Approved | Most recent IF: 3.133 | ||
| Call Number | EMAT @ emat @ c:irua:142367 | Serial | 4581 | ||
| Permanent link to this record | |||||
| Author | Batuk, D.; Batuk, M.; Filimonov, D.S.; Zakharov, K.V.; Volkova, O.S.; Vasiliev, A.N.; Tyablikov, O.A.; Hadermann, J.; Abakumov, A.M. | ||||
| Title | Crystal Structure, Defects, Magnetic and Dielectric Properties of the Layered Bi3n+1Ti7Fe3n-3,O9n+11 Perovskite-Anatase lntergrowths | Type | A1 Journal article | ||
| Year | 2017 | Publication | Inorganic chemistry | Abbreviated Journal | Inorg Chem |
| Volume | 56 | Issue | 56 | Pages | 931-942 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract |
The Bi3n+1Ti7Fe3n-3,O9n+11 materials are built of (001)(p) plane parallel perovskite blocks with a thickness of n (Ti,Fe)O-6 octahedra, separated by periodic translational interfaces. The interfaces are based on anatase-like chains of edge -sharing (Ti,Fe)O-6 octahedra. Together with the octahedra of the perovskite blocks, they create S-shaped tunnels stabilized by lone pair Bi3+ cations. In this work, the structure of the n = 4-6 Bi3n+1Ti7Fe3n-3,O9n+11 homologues is analyzed in detail using advanced transmission electron microscopy, powder X-ray diffraction, and Mossbauer spectroscopy. The connectivity of the anatase-like chains to the perovskite blocks results in,a 3ap periodicity along the interfaces, so that they can be located either on top of each other or with shifts of +/- a(p) along [100](p). The ordered arrangement of the interfaces gives rise to orthorhombic Immm and monoclinic A2/m polymorphs with the unit cell parameters a = 3a(p), b = b(p), c = 2(n + 1)c(p) and a = 3a(p), b = b(p), c = 2(n + 1)c(p) – a(p), respectively. While the n = 3 compound is orthorhombic, the monoclinic modification is more favorable in higher homologues. The Bi3n+1Ti7Fe3n-3,O9n+11 structures demonstrate intricate patterns of atomic displacements in the perovskite blocks, which are supported by the stereochemical activity of the Bi3+ cations. These patterns are coupled to the cationic coordination of the oxygen atoms in the (Ti,Fe)O-2 layers at the border of the perovskite blocks. The coupling is strong in the 1/ = 3, 4 homologues, but gradually reduces with the increasing thickness of the perovskite blocks, so that, in the n = 6 compound, the dominant mode of atomic displacements is aligned along the interface planes. The displacements in the adjacent perovskite blocks tend to order antiparallel, resulting in an overall antipolar structure. The Bi3n+1Ti7Fe3n-3,O9n+11 materials demonstrate an unusual diversity of structure defects. The n = 4-6 homologues are robust antiferromagnets below T-N = 135, 220, and 295 K, respectively. They show a high dielectric constant that weakly increases with temperature and is relatively insensitive to the Ti/Fe ratio. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Easton, Pa | Editor | ||
| Language | Wos | 000392262400029 | Publication Date | 2016-12-25 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0020-1669 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 4.857 | Times cited | 3 | Open Access | Not_Open_Access |
| Notes | ; The work was supported by the Russian Science Foundation (grant 14-13-00680). ; | Approved | Most recent IF: 4.857 | ||
| Call Number | UA @ lucian @ c:irua:141471 | Serial | 4495 | ||
| Permanent link to this record | |||||