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| Author | Kirsanova, M.A.; De Sloovere, D.; Karakulina, O.M.; Hadermann, J.; Van Bael, M.K.; Hardy, A.; Abakumov, A.M. | ||||
| Title | Toward unlocking the Mn3+/Mn2+ redox pair in alluaudite-type Na2+2zMn2-z(SO4)3-x(SeO4)x cathodes for sodium-ion batteries | Type | A1 Journal article | ||
| Year | 2019 | Publication | Journal of solid state chemistry | Abbreviated Journal | J Solid State Chem |
| Volume | 277 | Issue | 277 | Pages | 804-810 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | In polyanion cathodes, the inductive effect alters the potential of a M(n+1)+/Mn+ redox couple (M – transition metal) according to the electronegativity of the X cation in the polyanion groups (XO4m+). To manipulate the operating potential, we synthesized a series of mixed sulfate-selenate alluaudites, with structure formulas Na2+2zMn2-z(SO4)(3-x)(SeO4)(x) and Na2.81Ni1.60(SO4)(1.43)(SeO4)(1.57). Their crystal structure was determined from powder X-ray diffraction data, revealing that the Mn-based alluaudites form solid solutions with the same crystal structure for x = 0.75; 1.125 and 1.5. Na2.81Ni1.60(SO4)(1.43)(SeO4)(1.57) is isostructural to the Mn-based alluaudites. Although the Na2+2zMn2-z(SO4)(3-x)(SeO4)(x) compound with the highest selenium content demonstrates a reversible discharge capacity of 60 mAh g(-1), only a small part of this electrochemical activity can be ascribed to the Mn3+/Mn2+ redox couple. The redox potential of the Mn3+/Mn2+ pair in Na2+2zMn2-z(SO4)(3-)x(SeO4)(x) decreases with increasing values of x, in agreement with the lower electronegativity of Se compared to that of S. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000481726300103 | Publication Date | 2019-07-24 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0022-4596 | ISBN | Additional Links | UA library record; WoS full record | |
Impact Factor  |
2.299 | Times cited | Open Access | ||
| Notes | ; The authors thank the Russian Foundation for Basic Research for financial support (grant 17-03-00370), in addition to Research Foundation-Flanders (project No G040116). ; | Approved | Most recent IF: 2.299 | ||
| Call Number | UA @ admin @ c:irua:162852 | Serial | 5401 | ||
| Permanent link to this record | |||||
| Author | Hendrickx, M.; Tang, Y.; Hunter, E.C.; Battle, P.D.; Hadermann, J. | ||||
| Title | Structural and magnetic properties of the perovskites A₂LaFe₂SbO₉ (A = Ca, Sr, Ba) | Type | A1 Journal article | ||
| Year | 2021 | Publication | Journal Of Solid State Chemistry | Abbreviated Journal | J Solid State Chem |
| Volume | 295 | Issue | Pages | 121914 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Polycrystalline samples of A(2)LaFe(2)SbO(9) (A = Ca, Sr, Ba) perovskites appeared monophasic to X-ray or neutron powder diffraction but a single-crystal study utilising transmission electron microscopy revealed a greater level of complexity. Although local charge balance is maintained, compositional and structural variations are present among and within the submicron-sized crystals. Despite the inhomogeneity, A = Ca is monophasic with a partially-ordered distribution of Fe3+ and Sb5+ cations across two crystallographically-distinct octahedral sites, i.e. Ca2La(Fe1.25Sb0.25)(2d) (Fe0.75Sb0.75)(2c)O-9. For A = Sr or Ba, the inhomogeneities result in differences in the filling patterns of the octahedra and the ordering of the B cations. Particles of A = Sr contain a phase (Fe:Sb similar to 2:1) without B cation ordering and one (Fe:Sb similar to 1:1) with B cation ordering. Monophasic A = Ba lacks long-range cation order although ordered nanodomains are present within the disordered phase. The temperature dependence of the magnetic properties of each sample is discussed. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000615711800013 | Publication Date | 2020-12-17 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0022-4596 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor |
2.299 | Times cited | Open Access | OpenAccess | |
| Notes | Approved | Most recent IF: 2.299 | |||
| Call Number | UA @ admin @ c:irua:176663 | Serial | 6739 | ||
| Permanent link to this record | |||||
| Author | Golovachev, I.B.; Mychinko, M.Y.; Volkova, N.E.; Gavrilova, L.Y.; Raveau, B.; Maignan, A.; Cherepanov, V.A. | ||||
| Title | Effect of cobalt content on the properties of quintuple perovskites Sm₂Ba₃Fe₅-xCoxO₁₅-δ | Type | A1 Journal article | ||
| Year | 2021 | Publication | Journal Of Solid State Chemistry | Abbreviated Journal | J Solid State Chem |
| Volume | 301 | Issue | Pages | 122324 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Quintuple perovskites Sm2Ba3Fe5-xCoxO15-delta = 0.5, 1.0 and 1.5) have been prepared by glycerin-nitrate tech- nique in air. The phase purity was confirmed by XRD. Partial substitution of Co for Fe decreases the oxygen content and thus the mean oxidation state of 3d-metals. It also slightly decreases the thermal expansion coefficient of oxides. Positive value of the Seebeck coefficient confirmed p-type conductivity, though the thermopower decreases as the Co content increases. The temperature dependence of electrical conductivity reveals a maximum at 550-750 degrees C. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000684543700028 | Publication Date | 2021-06-03 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0022-4596 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor |
2.299 | Times cited | Open Access | OpenAccess | |
| Notes | Approved | Most recent IF: 2.299 | |||
| Call Number | UA @ admin @ c:irua:181656 | Serial | 6864 | ||
| Permanent link to this record | |||||
| Author | Pape, E.; Bezerra, T.N.; Vanneste, H.; Heeschen, K.; Moodley, L.; Leroux, F.; van Breugel, P.; Vanreusel, A. | ||||
| Title | Community structure and feeding preference of nematodes associated with methane seepage at the Darwin mud volcano (Gulf of Cádiz) | Type | A1 Journal article | ||
| Year | 2011 | Publication | Marine ecology progress series | Abbreviated Journal | Mar Ecol Prog Ser |
| Volume | 438 | Issue | Pages | 71-83 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | We sampled the Darwin mud volcano (MV) for meiofaunal community and trophic structure in relation to pore-water geochemistry along a 10 m transect from a seep site on the rim of the crater towards the MV slope. Pore-water profiles indicated considerable variation in upward methane (CH4) flow among sediment cores taken along the transect, with highest flux in the seep sediment core, gradually decreasing along the transect, to no CH4 flux in the core taken at a 5 m distance. Low sulphate concentrations and high levels of total alkalinity and sulphide (H2S) suggested that anaerobic oxidation of methane (AOM) occurred close to the sediment surface in the seep sediment core. High H2S levels had a genus- and species-specific impact on meiofaunal densities. Nematode genus composition varied gradually between sediment cores, with the genus Sabatieria dominating almost all sediment cores. However, genus diversity increased with increasing distance from the seep site. These limited data suggest that the community structure of seep meiofauna is highly dependent on local (a)biotic habitat characteristics, and a typical seep meiofaunal community cannot be delineated. Stable isotope values suggested the nematode diet up to 10 m from the seep site included thiotrophic carbon. The thicker hemipelagic sediment layer (photosynthetic carbon), the increased trophic diversity, and the heavier nematode δ13C farther from the seep site suggest a decrease in thiotrophy and an increase in photosynthetic carbon in the nematode diet. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Inter-research | Place of Publication | Halstenbek | Editor | |
| Language | Wos | 000295616000006 | Publication Date | 2011-07-06 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0171-8630;1616-1599; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor |
2.292 | Times cited | 18 | Open Access | |
| Notes | Approved | Most recent IF: 2.292; 2011 IF: 2.711 | |||
| Call Number | UA @ lucian @ c:irua:93682 | Serial | 414 | ||
| Permanent link to this record | |||||
| Author | Fang, C.M.; van Huis, M.A.; Zandbergen, H.W. | ||||
| Title | Stability and structures of the CFCC-TmC phases : a first-principles study | Type | A1 Journal article | ||
| Year | 2012 | Publication | Computational materials science | Abbreviated Journal | Comp Mater Sci |
| Volume | 51 | Issue | 1 | Pages | 146-150 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | The η-M6C, γ-M23C6, and π-M11C2 phases (M = Cr, Mn and Fe) have complex cubic lattices with lattice parameters of approximately 1.0 nm. They belong to the CFCC-TmC family (complex face-centered cubic transition metal carbides), display a rich variety of crystal structures, and play in important role in iron alloys and steels. Here we show that first-principles calculations predict high stability for the γ-M23C6 and η-M6C phases, and instability for the π-M11C2 phases, taking into account various compositional and structural possibilities. The calculations also show a wide variety in magnetic properties. The Cr-containing phases were found to be non-magnetic and the Fe-phases to be ferromagnetic, while the Mn-containing phases were found to be either ferrimagnetic or non-magnetic. Details of the local atomic structures, and the formation and stability of these precipitates in alloys are discussed. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000296214300020 | Publication Date | 2011-08-29 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0927-0256; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor |
2.292 | Times cited | 18 | Open Access | |
| Notes | Approved | Most recent IF: 2.292; 2012 IF: 1.878 | |||
| Call Number | UA @ lucian @ c:irua:93277 | Serial | 3119 | ||
| Permanent link to this record | |||||
| Author | Schryvers, D.; de Saegher, B.; van Landuyt, J. | ||||
| Title | Electron microscopy and diffraction study of the composition dependency of the 3R microtwinned martensite in Ni-Al | Type | A1 Journal article | ||
| Year | 1991 | Publication | Materials research bulletin | Abbreviated Journal | Mater Res Bull |
| Volume | 26 | Issue | Pages | 57-66 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | |||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | New York, N.Y. | Editor | ||
| Language | Wos | A1991EU98500007 | Publication Date | 0000-00-00 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0025-5408 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor |
2.288 | Times cited | 11 | Open Access | |
| Notes | Approved | no | |||
| Call Number | UA @ lucian @ c:irua:48348 | Serial | 943 | ||
| Permanent link to this record | |||||
| Author | Laffez, P.; Van Tendeloo, G.; Millange, F.; Caignaert, V.; Hervieu, M.; Raveau, B. | ||||
| Title | Structural phase transition at low temperature, corresponding to charge ordering in the CMR perovskites LN0.5A0.5MNO3 | Type | A1 Journal article | ||
| Year | 1996 | Publication | Materials research bulletin | Abbreviated Journal | Mater Res Bull |
| Volume | 31 | Issue | 8 | Pages | 905-911 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | The magneto resistive perovskites Nd0.5Sr0.5MnO3 and Pr0.5Sr0.41Ca0.09MnO3 undergo a transition from anti ferromagnetic insulator to ferromagnetic metal as function of temperature. The room temperature phase is orthorhombic with the space group Imma and the cell parameters a approximate to root 2a(p), b approximate to 2a(p), and c approximate to root 2a(p). A structural phase transition related to charge ordering accompanying the transition from ferromagnetic state to antiferromagnetic state has been evidenced by low temperature electron diffraction. This transition is reversible and a new superstructure, with a P-type orthorhombic cell. and lattice parameters parameters a approximate to 2 root 2a(p), b approximate to 2a(p), and c approximate to root 2a(p), is formed. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | New York, N.Y. | Editor | ||
| Language | Wos | A1996UZ37300002 | Publication Date | 2002-07-25 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0025-5408; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor |
2.288 | Times cited | 25 | Open Access | |
| Notes | Approved | ||||
| Call Number | UA @ lucian @ c:irua:99650 | Serial | 3246 | ||
| Permanent link to this record | |||||
| Author | Teodorescu, V.S.; Nistor, L.C.; van Landuyt, J.; Dinescu, M. | ||||
| Title | TEM study of laser induced phase transition in iron thin films | Type | A1 Journal article | ||
| Year | 1994 | Publication | Materials research bulletin | Abbreviated Journal | Mater Res Bull |
| Volume | 29 | Issue | 1 | Pages | 63-71 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Laser induced phase transition from b.c.c.(alpha) to f.c.c.(gamma) iron thin films is studied by high resolution TEM. The iron film has been covered on both sides with carbon layers to protect it against oxidation. Single pulse, tau FWHM = 20ns KrF (lambda = 248nm) excimer laser irradiation was performed in air with the film on the substrate. The laser pulse acts like a heat pulse followed by a rapid quenching revealing sequential aspects of the phase transition process. The presence of a fine mixture of the alpha + gamma phases between the alpha and gamma regions of the film has been interpreted as an incomplet transformation. The results are explained by assuming that the transformation took place via a phonon drag mechanism. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | New York, N.Y. | Editor | ||
| Language | Wos | A1994ML03000008 | Publication Date | 2003-06-21 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0025-5408; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor |
2.288 | Times cited | 2 | Open Access | |
| Notes | Approved | no | |||
| Call Number | UA @ lucian @ c:irua:99945 | Serial | 3488 | ||
| Permanent link to this record | |||||
| Author | Kuznetsov, A.S.; Cuong, N.T.; Tikhomirov, V.K.; Jivanescu, M.; Stesmans, A.; Chibotaru, L.F.; Velázquez, J.J.; Rodríguez, V.D.; Kirilenko, D.; Van Tendeloo, G.; Moshchalkov, V.V. | ||||
| Title | Effect of heat-treatment on luminescence and structure of Ag nanoclusters doped oxyfluoride glasses and implication for fiber drawing | Type | A1 Journal article | ||
| Year | 2012 | Publication | Optical materials | Abbreviated Journal | Opt Mater |
| Volume | 34 | Issue | 4 | Pages | 616-621 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | The effect of heat treatment on the structure and luminescence of Ag nanoclusters doped oxyfluoride glasses was studied and the implication for drawing the corresponding fibers doped with luminescent Ag nanoclusters has been proposed. The heat treatment results, first, in condensation of the Ag nanoclusters into larger Ag nanoparticles and loss of Ag luminescence, and further heat treatment results in precipitation of a luminescent-loss nano- and microcrystalline Ag phases onto the surface of the glass. Thus, the oxyfluoride fiber doped with luminescent Ag nanoclusters was pulled from the viscous glass melt and its attenuation loss was 0.19 dB/cm in the red part of the spectrum; i.e. near to the maximum of Ag nanoclusters luminescence band. The nucleation centers for the Ag nanoclusters in oxyfluoride glasses have been suggested to be the fluorine vacancies and their nanoclusters. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Amsterdam | Editor | ||
| Language | Wos | 000300124500006 | Publication Date | 2011-10-18 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0925-3467; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor |
2.238 | Times cited | 25 | Open Access | |
| Notes | Methusalem | Approved | Most recent IF: 2.238; 2012 IF: 1.918 | ||
| Call Number | UA @ lucian @ c:irua:93632 | Serial | 811 | ||
| Permanent link to this record | |||||
| Author | Krsmanovic, R.; Bals, S.; Bertoni, G.; Van Tendeloo, G. | ||||
| Title | Structural characterization of Er-doped Li2O-Al2O3-SiO2 glass ceramics | Type | A1 Journal article | ||
| Year | 2008 | Publication | Optical materials | Abbreviated Journal | Opt Mater |
| Volume | 30 | Issue | 7 | Pages | 1183-1188 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Particularly favourable properties of glass ceramics are developed on the basis of two key advantages of these materials: the variation of chemical composition and of microstructure. Therefore, detailed structural and chemical information are necessary to get insight in novel glass ceramic materials. We present here two examples of Er-doped Li2O-Al2O3-SiO2, with different quantities of ZrO2, both obtained with sol-gel synthesis. Different transmission electron microscopy techniques: conventional TEM, HRTEM, and EELS are used and the results are compared with those previously obtained with XRD and Rietveld analysis. We also demonstrate the 3D reconstruction, obtained from HAADF-STEM imaging, to determine the morphology of nanosize precipitates in these composites. (c) 2007 Elsevier B.V. All rights reserved. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Amsterdam | Editor | ||
| Language | Wos | 000254419100035 | Publication Date | 2007-07-11 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0925-3467; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor |
2.238 | Times cited | 12 | Open Access | |
| Notes | Iap-V1; Esteem | Approved | Most recent IF: 2.238; 2008 IF: 1.714 | ||
| Call Number | UA @ lucian @ c:irua:70004 | Serial | 3219 | ||
| Permanent link to this record | |||||
| Author | Gorlé, C.; Larsson, J.; Emory, M.; Iaccarino, G. | ||||
| Title | The deviation from parallel shear flow as an indicator of linear eddy-viscosity model inaccuracy | Type | A1 Journal article | ||
| Year | 2014 | Publication | Physics of fluids | Abbreviated Journal | Phys Fluids |
| Volume | 26 | Issue | 5 | Pages | 051702 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | A marker function designed to indicate in which regions of a generic flow field the results from linear eddy-viscosity turbulence models are plausibly inaccurate is introduced. The marker is defined to identify regions that deviate from parallel shear flow. For two different flow fields it is shown that these regions largely coincide with regions where the prediction of the Reynolds stress divergence is inaccurate. The marker therefore offers a guideline for interpreting results obtained from Reynolds-averaged Navier-Stokes simulations and provides a basis for the further development of turbulence model-form uncertainty quantification methods. (C) 2014 AIP Publishing LLC. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Woodbury, N.Y. | Editor | ||
| Language | Wos | 000337103900002 | Publication Date | 2014-05-15 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1070-6631;1089-7666; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor |
2.232 | Times cited | 19 | Open Access | |
| Notes | Approved | Most recent IF: 2.232; 2014 IF: 2.031 | |||
| Call Number | UA @ lucian @ c:irua:118385 | Serial | 684 | ||
| Permanent link to this record | |||||
| Author | Croitoru, M.D.; Gladilin, V.N.; Fomin, V.M.; Devreese, J.T.; Kemerink, M.; Koenraad, P.M.; Sauthoff, K.; Wolter, J.H. | ||||
| Title | Electroluminescence spectra of an STM-tip-induced quantum dot | Type | A1 Journal article | ||
| Year | 2004 | Publication | Physica. E: Low-dimensional systems and nanostructures | Abbreviated Journal | Physica E |
| Volume | 21 | Issue | Pages | 270-274 | |
| Keywords | A1 Journal article; Theory of quantum systems and complex systems; Condensed Matter Theory (CMT); Electron microscopy for materials research (EMAT) | ||||
| Abstract | |||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | North-Holland | Place of Publication | Amsterdam | Editor | |
| Language | Wos | 000220873300024 | Publication Date | 2004-01-30 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1386-9477; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor |
2.221 | Times cited | 1 | Open Access | |
| Notes | Approved | Most recent IF: 2.221; 2004 IF: 0.898 | |||
| Call Number | UA @ lucian @ c:irua:44291 | Serial | 901 | ||
| Permanent link to this record | |||||
| Author | Croitoru, M.D.; Gladilin, V.N.; Fomin, V.M.; Devreese, J.T.; Kemerink, M.; Koenraad, P.M.; Sauthoff, K.; Wolter, J.H. | ||||
| Title | Influence of the characteristics of the STM-tip on the electroluminescence spectra | Type | A1 Journal article | ||
| Year | 2005 | Publication | Physica. E: Low-dimensional systems and nanostructures | Abbreviated Journal | Physica E |
| Volume | 27 | Issue | Pages | 13-20 | |
| Keywords | A1 Journal article; Theory of quantum systems and complex systems; Condensed Matter Theory (CMT); Electron microscopy for materials research (EMAT) | ||||
| Abstract | |||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | North-Holland | Place of Publication | Amsterdam | Editor | |
| Language | Wos | 000227813200003 | Publication Date | 2004-12-16 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1386-9477; | ISBN | Additional Links | UA library record; WoS full record | |
| Impact Factor |
2.221 | Times cited | Open Access | ||
| Notes | Approved | Most recent IF: 2.221; 2005 IF: 0.946 | |||
| Call Number | UA @ lucian @ c:irua:52793 | Serial | 1645 | ||
| Permanent link to this record | |||||
| Author | Velazco, A.; Nord, M.; Béché, A.; Verbeeck, J. | ||||
| Title | Evaluation of different rectangular scan strategies for STEM imaging | Type | A1 Journal article | ||
| Year | 2020 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | Issue | Pages | 113021 | ||
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | STEM imaging is typically performed by raster scanning a focused electron probe over a sample. Here we investigate and compare three different scan patterns, making use of a programmable scan engine that allows to arbitrarily set the sequence of probe positions that are consecutively visited on the sample. We compare the typical raster scan with a so-called ‘snake’ pattern where the scan direction is reversed after each row and a novel Hilbert scan pattern that changes scan direction rapidly and provides an homogeneous treatment of both scan directions. We experimentally evaluate the imaging performance on a single crystal test sample by varying dwell time and evaluating behaviour with respect to sample drift. We demonstrate the ability of the Hilbert scan pattern to more faithfully represent the high frequency content of the image in the presence of sample drift. It is also shown that Hilbert scanning provides reduced bias when measuring lattice parameters from the obtained scanned images while maintaining similar precision in both scan directions which is especially important when e.g. performing strain analysis. Compared to raster scanning with flyback correction, both snake and Hilbert scanning benefit from dose reduction as only small probe movement steps occur. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000544042800007 | Publication Date | 2020-05-21 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0304-3991 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor |
2.2 | Times cited | 13 | Open Access | OpenAccess |
| Notes | A.V., A.B. and J.V. acknowledge funding through FWO project G093417N ('Compressed sensing enabling low dose imaging in transmission electron microscopy') from the Flanders Research Fund. M.N. received support for this work from the European Union's Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 838001. J.V acknowledges funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 823717 – ESTEEM3. | Approved | Most recent IF: 2.2; 2020 IF: 2.843 | ||
| Call Number | EMAT @ emat @c:irua:169225 | Serial | 6369 | ||
| Permanent link to this record | |||||
| Author | Fatermans, J.; den Dekker, Aj.; Müller-Caspary, K.; Gauquelin, N.; Verbeeck, J.; Van Aert, S. | ||||
| Title | Atom column detection from simultaneously acquired ABF and ADF STEM images | Type | A1 Journal article | ||
| Year | 2020 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | 219 | Issue | Pages | 113046 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab | ||||
| Abstract | In electron microscopy, the maximum a posteriori (MAP) probability rule has been introduced as a tool to determine the most probable atomic structure from high-resolution annular dark-field (ADF) scanning transmission electron microscopy (STEM) images exhibiting low contrast-to-noise ratio (CNR). Besides ADF imaging, STEM can also be applied in the annular bright-field (ABF) regime. The ABF STEM mode allows to directly visualize light-element atomic columns in the presence of heavy columns. Typically, light-element nanomaterials are sensitive to the electron beam, limiting the incoming electron dose in order to avoid beam damage and leading to images exhibiting low CNR. Therefore, it is of interest to apply the MAP probability rule not only to ADF STEM images, but to ABF STEM images as well. In this work, the methodology of the MAP rule, which combines statistical parameter estimation theory and model-order selection, is extended to be applied to simultaneously acquired ABF and ADF STEM images. For this, an extension of the commonly used parametric models in STEM is proposed. Hereby, the effect of specimen tilt has been taken into account, since small tilts from the crystal zone axis affect, especially, ABF STEM intensities. Using simulations as well as experimental data, it is shown that the proposed methodology can be successfully used to detect light elements in the presence of heavy elements. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000594768500005 | Publication Date | 2020-06-01 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0304-3991 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor |
2.2 | Times cited | 9 | Open Access | OpenAccess |
| Notes | The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (No. W.O.010.16N, No. G.0368.15N, No. G.0502.18N, EOS 30489208). This project has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (Grant Agreement No. 770887). The authors acknowledge funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No. 823717 – ESTEEM3. The direct electron detector (Medipix3, Quantum Detectors) was funded by the Hercules fund from the Flemish Government. K. M. C. acknowledges funding from the Initiative and Network Fund of the Helmholtz Association (Germany) under contract VH-NG-1317. The authors thank Mark Huijben from the University of Twente (Enschede, The Netherlands) for providing the LiMn2O4 sample used in section 4.2 of this study. N. G., J. V., and S. V. A. acknowledge funding from the University of Antwerp through the Concerted Research Actions (GOA) project Solarpaint and the TOP project. | Approved | Most recent IF: 2.2; 2020 IF: 2.843 | ||
| Call Number | EMAT @ emat @c:irua:169706 | Serial | 6373 | ||
| Permanent link to this record | |||||
| Author | Prabhakara, V.; Jannis, D.; Guzzinati, G.; Béché, A.; Bender, H.; Verbeeck, J. | ||||
| Title | HAADF-STEM block-scanning strategy for local measurement of strain at the nanoscale | Type | A1 Journal article | ||
| Year | 2020 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | 219 | Issue | Pages | 113099 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Lattice strain measurement of nanoscale semiconductor devices is crucial for the semiconductor industry as strain substantially improves the electrical performance of transistors. High resolution scanning transmission electron microscopy (HR-STEM) imaging is an excellent tool that provides spatial resolution at the atomic scale and strain information by applying Geometric Phase Analysis or image fitting procedures. However, HR-STEM images regularly suffer from scanning distortions and sample drift during image acquisition. In this paper, we propose a new scanning strategy that drastically reduces artefacts due to drift and scanning distortion, along with extending the field of view. It consists of the acquisition of a series of independent small subimages containing an atomic resolution image of the local lattice. All subimages are then analysed individually for strain by fitting a nonlinear model to the lattice images. The method allows flexible tuning of spatial resolution and the field of view within the limits of the dynamic range of the scan engine while maintaining atomic resolution sampling within the subimages. The obtained experimental strain maps are quantitatively benchmarked against the Bessel diffraction technique. We demonstrate that the proposed scanning strategy approaches the performance of the diffraction technique while having the advantage that it does not require specialized diffraction cameras. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000594768500006 | Publication Date | 2020-09-01 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0304-3991 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor |
2.2 | Times cited | 4 | Open Access | OpenAccess |
| Notes | A.B. D.J. and J.V. acknowledge funding through FWO project G093417N ('Compressed sensing enabling low dose imaging in transmission electron microscopy') from the Flanders Research Fund. J.V acknowledges funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 823717 – ESTEEM3. The Qu-Ant-EM microscope and the direct electron detector used in the diffraction experiments was partly funded by the Hercules fund from the Flemish Government. This project has received funding from the GOA project “Solarpaint” of the University of Antwerp. GG acknowledges support from a postdoctoral fellowship grant from the Fonds Wetenschappelijk Onderzoek – Vlaanderen (FWO). Special thanks to Dr. Thomas Nuytten, Prof. Dr. Wilfried Vandervorst, Dr. Paola Favia, Dr. Olivier Richard from IMEC, Leuven and Prof. Dr. Sara Bals from EMAT, Antwerp for their continuous support and collaboration with the project and to the IMEC processing group for the device fabrication. | Approved | Most recent IF: 2.2; 2020 IF: 2.843 | ||
| Call Number | EMAT @ emat @c:irua:172485 | Serial | 6404 | ||
| Permanent link to this record | |||||
| Author | De wael, A.; De Backer, A.; Van Aert, S. | ||||
| Title | Hidden Markov model for atom-counting from sequential ADF STEM images: Methodology, possibilities and limitations | Type | A1 Journal article | ||
| Year | 2020 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | 219 | Issue | Pages | 113131 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | We present a quantitative method which allows us to reliably measure dynamic changes in the atomic structure of monatomic crystalline nanomaterials from a time series of atomic resolution annular dark field scanning transmission electron microscopy images. The approach is based on the so-called hidden Markov model and estimates the number of atoms in each atomic column of the nanomaterial in each frame of the time series. We discuss the origin of the improved performance for time series atom-counting as compared to the current state-of-the-art atom-counting procedures, and show that the so-called transition probabilities that describe the probability for an atomic column to lose or gain one or more atoms from frame to frame are particularly important. Using these transition probabilities, we show that the method can also be used to estimate the probability and cross section related to structural changes. Furthermore, we explore the possibilities for applying the method to time series recorded under variable environmental conditions. The method is shown to be promising for a reliable quantitative analysis of dynamic processes such as surface diffusion, adatom dynamics, beam effects, or in situ experiments. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000594770500003 | Publication Date | 2020-10-03 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0304-3991 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor |
2.2 | Times cited | Open Access | OpenAccess | |
| Notes | This project has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (Grant Agreement No. 770887 and No. 823717 ESTEEM3). The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through grants to A.D.w. and A.D.B. and projects G.0502.18N and EOS 30489208. | Approved | Most recent IF: 2.2; 2020 IF: 2.843 | ||
| Call Number | EMAT @ emat @c:irua:172449 | Serial | 6417 | ||
| Permanent link to this record | |||||
| Author | Velazco, A.; Béché, A.; Jannis, D.; Verbeeck, J. | ||||
| Title | Reducing electron beam damage through alternative STEM scanning strategies, Part I: Experimental findings | Type | A1 Journal article | ||
| Year | 2022 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | 232 | Issue | Pages | 113398 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | The highly energetic electrons in a transmission electron microscope (TEM) can alter or even completely destroy the structure of samples before sufficient information can be obtained. This is especially problematic in the case of zeolites, organic and biological materials. As this effect depends on both the electron beam and the sample and can involve multiple damage pathways, its study remained difficult and is plagued with irreproducibility issues, circumstantial evidence, rumors, and a general lack of solid data. Here we take on the experimental challenge to investigate the role of the STEM scan pattern on the damage behavior of a commercially available zeolite sample with the clear aim to make our observations as reproducible as possible. We make use of a freely programmable scan engine that gives full control over the tempospatial distribution of the electron probe on the sample and we use its flexibility to obtain multiple repeated experiments under identical conditions comparing the difference in beam damage between a conventional raster scan pattern and a newly proposed interleaved scan pattern that provides exactly the same dose and dose rate and visits exactly the same scan points. We observe a significant difference in beam damage for both patterns with up to 11 % reduction in damage (measured from mass loss). These observations demonstrate without doubt that electron dose, dose rate and acceleration voltage are not the only parameters affecting beam damage in (S)TEM experiments and invite the community to rethink beam damage as an unavoidable consequence of applied electron dose. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000714819200002 | Publication Date | 2021-10-02 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0304-3991 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor |
2.2 | Times cited | 18 | Open Access | OpenAccess |
| Notes | A.V., D.J., A.B. and J.V. acknowledge funding from FWO project G093417N (’Compressed sensing enabling low dose imaging in transmission electron microscopy’) and G042920N (’Coincident event detection for advanced spectroscopy in transmission electron microscopy’). This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 823717 ESTEEM3. The Qu-Ant-EM microscope was partly funded by the Hercules fund from the Flemish Government. J.V. acknowledges funding from GOA project “Solarpaint” of the University of Antwerp.; JRA; reported | Approved | Most recent IF: 2.2 | ||
| Call Number | EMAT @ emat @c:irua:183282 | Serial | 6818 | ||
| Permanent link to this record | |||||
| Author | Jannis, D.; Hofer, C.; Gao, C.; Xie, X.; Béché, A.; Pennycook, Tj.; Verbeeck, J. | ||||
| Title | Event driven 4D STEM acquisition with a Timepix3 detector: Microsecond dwell time and faster scans for high precision and low dose applications | Type | A1 Journal article | ||
| Year | 2022 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | 233 | Issue | Pages | 113423 | |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Four dimensional scanning transmission electron microscopy (4D STEM) records the scattering of electrons in a material in great detail. The benefits offered by 4D STEM are substantial, with the wealth of data it provides facilitating for instance high precision, high electron dose efficiency phase imaging via centre of mass or ptychography based analysis. However the requirement for a 2D image of the scattering to be recorded at each probe position has long placed a severe bottleneck on the speed at which 4D STEM can be performed. Recent advances in camera technology have greatly reduced this bottleneck, with the detection efficiency of direct electron detectors being especially well suited to the technique. However even the fastest frame driven pixelated detectors still significantly limit the scan speed which can be used in 4D STEM, making the resulting data susceptible to drift and hampering its use for low dose beam sensitive applications. Here we report the development of the use of an event driven Timepix3 direct electron camera that allows us to overcome this bottleneck and achieve 4D STEM dwell times down to 100 ns; orders of magnitude faster than what has been possible with frame based readout. We characterize the detector for different acceleration voltages and show that the method is especially well suited for low dose imaging and promises rich datasets without compromising dwell time when compared to conventional STEM imaging. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000734396800003 | Publication Date | 2021-11-13 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0304-3991 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor |
2.2 | Times cited | 31 | Open Access | OpenAccess |
| Notes | This project has received funding from the Euro- pean Union’s Horizon 2020 Research Infrastructure – Integrating Activities for Advanced Communities under grant agreement No 823717 – ESTEEM3. J.V. and A.B. acknowledge funding from FWO project G093417N (‘Compressed sensing enabling low dose imaging in transmission electron microscopy’). J.V. and D.J. ac- knowledge funding from FWO project G042920N ‘Co- incident event detection for advanced spectroscopy in transmission electron microscopy’. We acknowledge funding under the European Union’s Horizon 2020 re- search and innovation programme (J.V. and D.J un- der grant agreement No 101017720, FET-Proactive EBEAM, and C.H., C.G., X.X. and T.J.P. from the Eu- ropean Research Council (ERC) Grant agreement No. 802123-HDEM).; esteem3JRA; esteem3reported | Approved | Most recent IF: 2.2 | ||
| Call Number | EMAT @ emat @c:irua:183948 | Serial | 6828 | ||
| Permanent link to this record | |||||
| Author | Hofer, C.; Pennycook, T.J. | ||||
| Title | Reliable phase quantification in focused probe electron ptychography of thin materials | Type | A1 Journal Article | ||
| Year | 2023 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | 254 | Issue | Pages | 113829 | |
| Keywords | A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; | ||||
| Abstract | Electron ptychography provides highly sensitive, dose efficient phase images which can be corrected for aberrations after the data has been acquired. This is crucial when very precise quantification is required, such as with sensitivity to charge transfer due to bonding. Drift can now be essentially eliminated as a major impediment to focused probe ptychography, which benefits from the availability of easily interpretable simultaneous Z-contrast imaging. However challenges have remained when quantifying the ptychographic phases of atomic sites. The phase response of a single atom has a negative halo which can cause atoms to reduce in phase when brought closer together. When unaccounted for, as in integrating methods of quantification, this effect can completely obscure the effects of charge transfer. Here we provide a new method of quantification that overcomes this challenge, at least for 2D materials, and is robust to experimental parameters such as noise, sample tilt. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 001071608700001 | Publication Date | 2023-08-18 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0304-3991 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor |
2.2 | Times cited | Open Access | ||
| Notes | FWO, G013122N ; Horizon 2020 Framework Programme; Horizon 2020; European Research Council, 802123-HDEM ; European Research Council; | Approved | Most recent IF: 2.2; 2023 IF: 2.843 | ||
| Call Number | EMAT @ emat @c:irua:200272 | Serial | 8987 | ||
| Permanent link to this record | |||||
| Author | Gorji, S.; Kashiwar, A.; Mantha, L.S.; Kruk, R.; Witte, R.; Marek, P.; Hahn, H.; Kübel, C.; Scherer, T. | ||||
| Title | Nanowire facilitated transfer of sensitive TEM samples in a FIB | Type | A1 Journal article | ||
| Year | 2020 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | 219 | Issue | Pages | 113075 | |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | We introduce a facile approach to transfer thin films and other mechanically sensitive TEM samples inside a FIB with minimal introduction of stress and bending. The method is making use of a pre-synthetized flexible freestanding Ag nanowire attached to the tip of a typical tungsten micromanipulator inside the FIB. The main advantages of this approach are the significantly reduced stress-induced bending during transfer and attachment of the TEM sample, the very short time required to attach and cut the nanowire, the operation at very low dose and ion current, and only using the e-beam for Pt deposition during the transfer of sensitive TEM samples. This results in a reduced sample preparation time and reduced exposure to the ion beam or e-beam for Pt deposition during the sample preparation and thus also reduced contamination and beam damage. The method was applied to a number of thin films and different TEM samples in order to illustrate the advantageous benefits of the concept. In particular, the technique has been successfully tested for the transfer of a thin film onto a MEMS heating chip for in situ TEM experiments. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | Publication Date | 2020-07-15 | ||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0304-3991 | ISBN | Additional Links | UA library record | |
| Impact Factor |
2.2 | Times cited | Open Access | ||
| Notes | Approved | Most recent IF: 2.2; 2020 IF: 2.843 | |||
| Call Number | UA @ admin @ c:irua:183618 | Serial | 6871 | ||
| Permanent link to this record | |||||
| Author | Robert, Hl.; Lobato, I.; Lyu, Fj.; Chen, Q.; Van Aert, S.; Van Dyck, D.; Müller-Caspary, K. | ||||
| Title | Dynamical diffraction of high-energy electrons investigated by focal series momentum-resolved scanning transmission electron microscopy at atomic resolution | Type | A1 Journal article | ||
| Year | 2022 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | 233 | Issue | Pages | 113425 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab | ||||
| Abstract | We report a study of scattering dynamics in crystals employing momentum-resolved scanning transmission electron microscopy under varying illumination conditions. As we perform successive changes of the probe focus, multiple real-space signals are obtained in dependence of the shape of the incident electron wave. With support from extensive simulations, each signal is shown to be characterised by an optimum focus for which the contrast is maximum and which differs among different signals. For instance, a systematic focus mismatch is found between images formed by high-angle scattering, being sensitive to thickness and chemical composition, and the first moment in diffraction space, being sensitive to electric fields. It follows that a single recording at one specific probe focus is usually insufficient to characterise materials comprehensively. Most importantly, we demonstrate in experiment and simulation that the second moment ( |
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000734396800009 | Publication Date | 2021-11-13 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0304-3991 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor |
2.2 | Times cited | Open Access | OpenAccess | |
| Notes | We thank Dr. Florian Winkler for valuable discussions and experimental work at the early stages of this study. This work was supported by the Initiative and Network Fund of the Helmholtz Association (Germany) under contracts VH-NG-1317 and ZT-I-0025. This project furthermore received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (grant agreement No. 770887). | Approved | Most recent IF: 2.2 | ||
| Call Number | EMAT @ emat @c:irua:184833 | Serial | 6898 | ||
| Permanent link to this record | |||||
| Author | Jannis, D.; Velazco, A.; Béché, A.; Verbeeck, J. | ||||
| Title | Reducing electron beam damage through alternative STEM scanning strategies, Part II: Attempt towards an empirical model describing the damage process | Type | A1 Journal article | ||
| Year | 2022 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | Issue | Pages | 113568 | ||
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | In this second part of a series we attempt to construct an empirical model that can mimick all experimental observations made regarding the role of an alternative interleaved scan pattern in STEM imaging on the beam damage in a specific zeolite sample. We make use of a 2D diffusion model that describes the dissipation of the deposited beam energy in the sequence of probe positions that are visited during the scan pattern. The diffusion process allows for the concept of trying to ‘outrun’ the beam damage by carefully tuning the dwell time and distance between consecutively visited probe positions. We add a non linear function to include a threshold effect and evaluate the accumulated damage in each part of the image as a function of scan pattern details. Together, these ingredients are able to describe qualitatively all aspects of the experimental data and provide us with a model that could guide a further optimisation towards even lower beam damage without lowering the applied electron dose. We deliberately remain vague on what is diffusing here which avoids introducing too many sample specific details. This provides hope that the model can be applied also in sample classes that were not yet studied in such great detail by adjusting higher level parameters: a sample dependent diffusion constant and damage threshold. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000832788000003 | Publication Date | 0000-00-00 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0304-3991 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor |
2.2 | Times cited | 4 | Open Access | OpenAccess |
| Notes | D.J., A.V, A.B. and J.V. acknowledge funding from FWO project G093417N (’Compressed sensing enabling low dose imaging in transmission electron microscopy’) and G042920N (’Coincident event detection for advanced spectroscopy in transmission electron microscopy’). This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 823717 ESTEEM3. The Qu-Ant-EM microscope was partly funded by the Hercules fund from the Flemish Government. J.V. acknowledges funding from GOA project “Solarpaint” of the University of Antwerp .; esteem3reported; esteem3jra; | Approved | Most recent IF: 2.2 | ||
| Call Number | EMAT @ emat @c:irua:188535 | Serial | 7071 | ||
| Permanent link to this record | |||||
| Author | Hofer, C.; Gao, C.; Chennit, T.; Yuan, B.; Pennycook, T.J. | ||||
| Title | Phase offset method of ptychographic contrast reversal correction | Type | A1 Journal article | ||
| Year | 2024 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | Issue | Pages | 113922 | ||
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | |||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 001164447000001 | Publication Date | 2024-01-08 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0304-3991 | ISBN | Additional Links | UA library record; WoS full record | |
| Impact Factor |
2.2 | Times cited | Open Access | Not_Open_Access | |
| Notes | FWO, G013122N ; Horizon 2020 Framework Programme; European Research Council, 802123-HDEM ; European Research Council; | Approved | Most recent IF: 2.2; 2024 IF: 2.843 | ||
| Call Number | EMAT @ emat @c:irua:202379 | Serial | 8988 | ||
| Permanent link to this record | |||||
| Author | Sentürk, D.G.; De Backer, A.; Friedrich, T.; Van Aert, S. | ||||
| Title | Optimal experiment design for element specific atom counting using multiple annular dark field scanning transmission electron microscopy detectors | Type | A1 Journal article | ||
| Year | 2022 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | 242 | Issue | Pages | 113626 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | This paper investigates the possible benefits for counting atoms of different chemical nature when analysing multiple 2D scanning transmission electron microscopy (STEM) images resulting from independent annular dark field (ADF) detector regimes. To reach this goal, the principles of statistical detection theory are used to quantify the probability of error when determining the number of atoms in atomic columns consisting of multiple types of elements. In order to apply this theory, atom-counting is formulated as a statistical hypothesis test, where each hypothesis corresponds to a specific number of atoms of each atom type in an atomic column. The probability of error, which is limited by the unavoidable presence of electron counting noise, can then be computed from scattering-cross sections extracted from multiple ADF STEM images. Minimisation of the probability of error as a function of the inner and outer angles of a specified number of independent ADF collection regimes results in optimal experimental designs. Based on simulations of spherical Au@Ag and Au@Pt core–shell nanoparticles, we investigate how the combination of two non-overlapping detector regimes helps to improve the probability of error when unscrambling two types of atoms. In particular, the combination of a narrow low angle ADF detector with a detector formed by the remaining annular collection regime is found to be optimal. The benefit is more significant if the atomic number Z difference becomes larger. In addition, we show the benefit of subdividing the detector regime into three collection areas for heterogeneous nanostructures based on a structure consisting of three types of elements, e.g., a mixture of Au, Ag and Al atoms. Finally, these results are compared with the probability of error resulting when one would ultimately use a pixelated 4D STEM detector and how this could help to further reduce the incident electron dose. |
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000873778100001 | Publication Date | 0000-00-00 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0304-3991 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor |
2.2 | Times cited | Open Access | OpenAccess | |
| Notes | This work was supported by the European Research Council (Grant 770887 PICOMETRICS to S. Van Aert and Grant 823717 ESTEEM3). The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0346.21N and EOS 30489208) and a postdoctoral grant to A. De Backer. S. Van Aert acknowledges funding from the University of Antwerp Research fund (BOF).; esteem3reported; esteem3jra | Approved | Most recent IF: 2.2 | ||
| Call Number | EMAT @ emat @c:irua:190925 | Serial | 7118 | ||
| Permanent link to this record | |||||
| Author | De Backer, A.; Bals, S.; Van Aert, S. | ||||
| Title | A decade of atom-counting in STEM: From the first results toward reliable 3D atomic models from a single projection | Type | A1 Journal article | ||
| Year | 2023 | Publication | Ultramicroscopy | Abbreviated Journal | |
| Volume | Issue | Pages | 113702 | ||
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Quantitative structure determination is needed in order to study and understand nanomaterials at the atomic scale. Materials characterisation resulting in precise structural information is a crucial point to understand the structure–property relation of materials. Counting the number of atoms and retrieving the 3D atomic structure of nanoparticles plays an important role here. In this paper, an overview will be given of the atom-counting methodology and its applications over the past decade. The procedure to count the number of atoms will be discussed in detail and it will be shown how the performance of the method can be further improved. Furthermore, advances toward mixed element nanostructures, 3D atomic modelling based on the atom-counting results, and quantifying the nanoparticle dynamics will be highlighted. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000953765800001 | Publication Date | 2023-02-10 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0304-3991 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor |
2.2 | Times cited | 3 | Open Access | OpenAccess |
| Notes | This work was supported by the European Research Council (Grant 770887 PICOMETRICS to S. Van Aert, Grant 815128 REALNANO to S. Bals, and Grant 823717 ESTEEM3). The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0267.18N, G.0502.18N, G.0346.21N, and EOS 30489208) and a postdoctoral grant to A. De Backer. S. Van Aert acknowledges funding from the University of Antwerp Research fund (BOF) . The authors also thank the colleagues who have contributed to this work over the years, including T. Altantzis, E. Arslan Irmak, K.J. Batenburg, E. Bladt, A. De wael, R. Erni, C. Faes, B. Goris, L. Jones, L.M. Liz-Marzán, I. Lobato, G.T. Martinez, P.D. Nellist, M.D. Rosell, A. Rosenauer, K.H.W. van den Bos, A. Varambhia, and Z. Zhang.; esteem3reported; esteem3JRA | Approved | Most recent IF: 2.2; 2023 IF: 2.843 | ||
| Call Number | EMAT @ emat @c:irua:195896 | Serial | 7236 | ||
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| Author | Zhang, Z.; Lobato, I.; De Backer, A.; Van Aert, S.; Nellist, P. | ||||
| Title | Fast generation of calculated ADF-EDX scattering cross-sections under channelling conditions | Type | A1 Journal article | ||
| Year | 2023 | Publication | Ultramicroscopy | Abbreviated Journal | |
| Volume | 246 | Issue | Pages | 113671 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Advanced materials often consist of multiple elements which are arranged in a complicated structure. Quantitative scanning transmission electron microscopy is useful to determine the composition and thickness of nanostructures at the atomic scale. However, significant difficulties remain to quantify mixed columns by comparing the resulting atomic resolution images and spectroscopy data with multislice simulations where dynamic scattering needs to be taken into account. The combination of the computationally intensive nature of these simulations and the enormous amount of possible mixed column configurations for a given composition indeed severely hamper the quantification process. To overcome these challenges, we here report the development of an incoherent non-linear method for the fast prediction of ADF-EDX scattering cross-sections of mixed columns under channelling conditions. We first explain the origin of the ADF and EDX incoherence from scattering physics suggesting a linear dependence between those two signals in the case of a high-angle ADF detector. Taking EDX as a perfect incoherent reference mode, we quantitatively examine the ADF longitudinal incoherence under different microscope conditions using multislice simulations. Based on incoherent imaging, the atomic lensing model previously developed for ADF is now expanded to EDX, which yields ADF-EDX scattering cross-section predictions in good agreement with multislice simulations for mixed columns in a core–shell nanoparticle and a high entropy alloy. The fast and accurate prediction of ADF-EDX scattering cross-sections opens up new opportunities to explore the wide range of ordering possibilities of heterogeneous materials with multiple elements. | ||||
| Address | |||||
| Corporate Author | Zezhong Zhang | Thesis | |||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000995063900001 | Publication Date | 2022-12-28 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0304-3991 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor |
2.2 | Times cited | Open Access | OpenAccess | |
| Notes | European Research Council 770887 PICOMETRICS; Fonds Wetenschappelijk Onderzoek No.G.0502.18N; Horizon 2020, 770887 ; Horizon 2020 Framework Programme; European Research Council, 823717 ESTEEM3 ; esteem3reported; esteem3JRa | Approved | Most recent IF: 2.2; 2023 IF: 2.843 | ||
| Call Number | EMAT @ emat @c:irua:195890 | Serial | 7251 | ||
| Permanent link to this record | |||||
| Author | Lobato, I.; De Backer, A.; Van Aert, S. | ||||
| Title | Real-time simulations of ADF STEM probe position-integrated scattering cross-sections for single element fcc crystals in zone axis orientation using a densely connected neural network | Type | A1 Journal article | ||
| Year | 2023 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | 251 | Issue | Pages | 113769 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Quantification of annular dark field (ADF) scanning transmission electron microscopy (STEM) images in terms of composition or thickness often relies on probe-position integrated scattering cross sections (PPISCS). In order to compare experimental PPISCS with theoretically predicted ones, expensive simulations are needed for a given specimen, zone axis orientation, and a variety of microscope settings. The computation time of such simulations can be in the order of hours using a single GPU card. ADF STEM simulations can be efficiently parallelized using multiple GPUs, as the calculation of each pixel is independent of other pixels. However, most research groups do not have the necessary hardware, and, in the best-case scenario, the simulation time will only be reduced proportionally to the number of GPUs used. In this manuscript, we use a learning approach and present a densely connected neural network that is able to perform real-time ADF STEM PPISCS predictions as a function of atomic column thickness for most common face-centered cubic (fcc) crystals (i.e., Al, Cu, Pd, Ag, Pt, Au and Pb) along [100] and [111] zone axis orientations, root-mean-square displacements, and microscope parameters. The proposed architecture is parameter efficient and yields accurate predictions for the PPISCS values for a wide range of input parameters that are commonly used for aberration-corrected transmission electron microscopes. |
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| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 001011617200001 | Publication Date | 2023-06-01 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0304-3991 | ISBN | Additional Links | UA library record; WoS full record | |
| Impact Factor |
2.2 | Times cited | Open Access | OpenAccess | |
| Notes | This work was supported by the European Research Council (Grant 770887 PICOMETRICS to S. Van Aert). The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (G034621N and G0A7723N) and a postdoctoral grant to A. De Backer. S. Van Aert acknowledges funding from the University of Antwerp Research fund (BOF), Belgium. | Approved | Most recent IF: 2.2; 2023 IF: 2.843 | ||
| Call Number | EMAT @ emat @c:irua:197275 | Serial | 8812 | ||
| Permanent link to this record | |||||
| Author | Denisov, N.; Jannis, D.; Orekhov, A.; Müller-Caspary, K.; Verbeeck, J. | ||||
| Title | Characterization of a Timepix detector for use in SEM acceleration voltage range | Type | A1 Journal article | ||
| Year | 2023 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | 253 | Issue | Pages | 113777 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Hybrid pixel direct electron detectors are gaining popularity in electron microscopy due to their excellent properties. Some commercial cameras based on this technology are relatively affordable which makes them attractive tools for experimentation especially in combination with an SEM setup. To support this, a detector characterization (Modulation Transfer Function, Detective Quantum Efficiency) of an Advacam Minipix and Advacam Advapix detector in the 15–30 keV range was made. In the current work we present images of Point Spread Function, plots of MTF/DQE curves and values of DQE(0) for these detectors. At low beam currents, the silicon detector layer behaviour should be dominant, which could make these findings transferable to any other available detector based on either Medipix2, Timepix or Timepix3 provided the same detector layer is used. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 001026912700001 | Publication Date | 2023-06-08 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0304-3991 | ISBN | Additional Links | UA library record; WoS full record | |
| Impact Factor |
2.2 | Times cited | Open Access | OpenAccess | |
| Notes | The authors acknowledge the financial support of the Research Foundation Flanders (FWO, Belgium) project SBO S000121N. The authors are grateful to Dr. Lobato for productive discussion of methods. | Approved | Most recent IF: 2.2; 2023 IF: 2.843 | ||
| Call Number | EMAT @ emat @c:irua:198258 | Serial | 8815 | ||
| Permanent link to this record | |||||
| Author | Şentürk, DG.; Yu, CP.; De Backer, A.; Van Aert, S. | ||||
| Title | Atom counting from a combination of two ADF STEM images | Type | A1 Journal article | ||
| Year | 2024 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | 255 | Issue | Pages | 113859 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | To understand the structure–property relationship of nanostructures, reliably quantifying parameters, such as the number of atoms along the projection direction, is important. Advanced statistical methodologies have made it possible to count the number of atoms for monotype crystalline nanoparticles from a single ADF STEM image. Recent developments enable one to simultaneously acquire multiple ADF STEM images. Here, we present an extended statistics-based method for atom counting from a combination of multiple statistically independent ADF STEM images reconstructed from non-overlapping annular detector collection regions which improves the accuracy and allows one to retrieve precise atom-counts, especially for images acquired with low electron doses and multiple element structures. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 001089064200001 | Publication Date | 2023-09-23 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0304-3991 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor |
2.2 | Times cited | Open Access | OpenAccess | |
| Notes | This work was supported by the European Research Council (Grant 770887 PICOMETRICS to S. Van Aert). The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (G034621N, G0A7723N, and EOS 40007495) and a postdoctoral grant to A. De Backer. S. Van Aert acknowledges funding from the University of Antwerp Research fund (BOF). | Approved | Most recent IF: 2.2; 2024 IF: 2.843 | ||
| Call Number | EMAT @ emat @c:irua:201008 | Serial | 8964 | ||
| Permanent link to this record | |||||