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“TEM investigation of the microstructure and defects of CuZr martensite: 1: morphology and twin systems”. Seo JW, Schryvers D, Acta materialia 46, 1165 (1998). http://doi.org/10.1016/S1359-6454(97)00333-9
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 5.301
Times cited: 46
DOI: 10.1016/S1359-6454(97)00333-9
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“Ga segregation in DyBa2Cu3O7-\delta/PrBa2Cu3-xGaxO7-\delta/DyBa2Cu3O7-\delta ramp-type Josephson junctions”. Verbist K, Lebedev OI, Van Tendeloo G, Verhoeven MAJ, Rijnders AJHM, Blank DHA, Rogalia H, Applied physics letters 70, 1167 (1997)
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.411
Times cited: 8
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“Multi-functional copper oxide nanosystems for H2 sustainable production and sensing”. Gasparotto A, Barreca D, Fornasiero P, Gombac V, Lebedev O, Maccato C, Montini T, Tondello E, Van Tendeloo G, Comini E, Sberveglieri G, ECS transactions 25, 1169 (2009)
Abstract: This work focuses on the use of tailored copper oxide nanoarchitectures as multi-functional materials for the sustainable production of hydrogen and its on-line detection. An innovative copper(II) precursor, Cu(hfa)2TMEDA, was adopted in the CVD of CuxO (x=1,2) nanosystems under both O2 and O2+H2O atmospheres on Si(100) and Al2O3 substrates. A multi-technique characterization indicates that both the phase composition (from Cu2O to CuO) and morphology (from continuous films to entangled quasi-1D nanosystems) can be tailored by varying the growth temperature and reaction atmosphere. The obtained CuxO nanodeposits are active in the photocatalytic H2 production from aqueous solutions under UV-Vis irradiation and display interesting gas sensing performances towards hydrogen detection even at moderate temperatures.
Keywords: A2 Journal article; Electron microscopy for materials research (EMAT)
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“Size of cerium dioxide support nanocrystals dictates reactivity of highly dispersed palladium catalysts”. Muravev V, Parastaev A, van den Bosch Y, Ligt B, Claes N, Bals S, Kosinov N, Hensen EJM, Science 380, 1174 (2023). http://doi.org/10.1126/science.adf9082
Abstract: The catalytic performance of heterogeneous catalysts can be tuned by modulation of the size and structure of supported transition metals, which are typically regarded as the active sites. In single-atom metal catalysts, the support itself can strongly affect the catalytic properties. Here, we demonstrate that the size of cerium dioxide (CeO2) support governs the reactivity of atomically dispersed palladium (Pd) in carbon monoxide (CO) oxidation. Catalysts with small CeO2 nanocrystals (~4 nanometers) exhibit unusually high activity in a CO-rich reaction feed, whereas catalysts with medium-size CeO2 (~8 nanometers) are preferred for lean conditions. Detailed spectroscopic investigations reveal support size–dependent redox properties of the Pd-CeO2 interface.
Keywords: A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Impact Factor: 56.9
Times cited: 22
DOI: 10.1126/science.adf9082
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“TEM investigation of the microstructure and defects of CuZr martensite: 2: planar defects”. Seo JW, Schryvers D, Acta materialia 46, 1177 (1998). http://doi.org/10.1016/S1359-6454(97)00334-0
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 5.301
Times cited: 21
DOI: 10.1016/S1359-6454(97)00334-0
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“A transmission electron microscopy study of tweed-like structures in Al62Cu17.5CO17.5Si3 decagonal quasicrystals”. Zhang Z, Geng W, van Landuyt J, Van Tendeloo G, Philosophical magazine: A: physics of condensed matter: defects and mechanical properties 71, 1177 (1995)
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Times cited: 7
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“[SrF0.8(OH)0.2]2.526[Mn6O12]: columnar rock-salt fragments inside the todorokite-type tunnel structure”. Abakumov AM, Hadermann J, Van Tendeloo G, Kovba ML, Skolis YY, Mudretsova SN, Antipov EV, Volkova OS, Vasiliev AN, Tristan N, Klingeler R, Büchner B, Chemistry of materials 19, 1181 (2007). http://doi.org/10.1021/cm062508s
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 9.466
Times cited: 9
DOI: 10.1021/cm062508s
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“Structural characterization of Er-doped Li2O-Al2O3-SiO2 glass ceramics”. Krsmanovic R, Bals S, Bertoni G, Van Tendeloo G, Optical materials 30, 1183 (2008). http://doi.org/10.1016/j.optmat.2007.05.045
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.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 2.238
Times cited: 12
DOI: 10.1016/j.optmat.2007.05.045
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“Ag1/8Pr5/8MoO4: an incommensurately modulated scheelite-type structure”. Morozov VA, Mironov AV, Lazoryak BI, Khaikina EG, Basovich OM, Rossell MD, Van Tendeloo G, Journal of solid state chemistry 179, 1183 (2006). http://doi.org/10.1016/j.jssc.2005.12.041
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 2.299
Times cited: 35
DOI: 10.1016/j.jssc.2005.12.041
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“Achieving High Moisture Tolerance in Pseudohalide Perovskite Nanocrystals for Light-Emitting Diode Application”. Bhatia H, Keshavarz M, Martin C, Van Gaal L, Zhang Y, de Coen B, Schrenker NJ, Valli D, Ottesen M, Bremholm M, Van de Vondel J, Bals S, Hofkens J, Debroye E, ACS Applied Optical Materials 1, 1184 (2023). http://doi.org/10.1021/acsaom.3c00096
Abstract: The addition of potassium thiocyanate (KSCN) to the FAPbBr3 structure and subsequent post-treatment of nanocrystals (NCs) lead to high quantum confinement, resulting in a photoluminescent quantum yield (PLQY) approaching unity and microsecond decay times. This synergistic approach demonstrated exceptional stability under humid conditions, retaining 70% of the PLQY for over a month, while the untreated NCs degrade within 24 h. Additionally, the devices incorporating the post-treated NCs displayed 1.5% external quantum efficiency (EQE), a 5-fold improvement over untreated devices. These results provide promising opportunities for the use of perovskites in moisture-stable optoelectronics.
Keywords: A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ;
DOI: 10.1021/acsaom.3c00096
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“Three-Dimensional Nanoparticle Transformations Captured by an Electron Microscope”. Albrecht W, Van Aert S, Bals S, Accounts Of Chemical Research 54, 1189 (2021). http://doi.org/10.1021/acs.accounts.0c00711
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 20.268
Times cited: 12
DOI: 10.1021/acs.accounts.0c00711
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“Morphological TEM studies and magnetoresistance analysis of sputtered Al-substituted ZnO films : the role of oxygen”. Van Gompel M, Atalay AY, Gaulke A, Van Bael MK, D'Haen J, Turner S, Van Tendeloo G, Vanacken J, Moshchalkov VV, Wagner P, Physica status solidi : A : applications and materials science 212, 1191 (2015). http://doi.org/10.1002/pssa.201431888
Abstract: In this article, we report on the synthesis of thin, epitaxial films of the transparent conductive oxide Al:ZnO on (0001)-oriented synthetic sapphire substrates by DC sputtering from targets with a nominal 1 at.% Al substitution. The deposition was carried out at an unusually low substrate temperature of only 250 °C in argonoxygen mixtures as well as in pure argon. The impact of the processgas composition on the morphology was analysed by transmission electron microscopy, revealing epitaxial growth in all the cases with a minor impact of the process parameters on the resulting grain sizes. The transport properties resistivity, Hall effect and magnetoresistance were studied in the range from 10 to 300 K in DC and pulsed magnetic fields up to 45 T. While the carrier density and mobility are widely temperature independent, we identified a low fieldlow temperature regime in which the magnetoresistance shows an anomalous, negative behaviour. At higher fields and temperatures, the magnetoresistance exhibits a more conventional, positive curvature with increasing field strength. As a possible explanation, we propose carrier scattering at localised magnetic trace impurities and magnetic correlations.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 1.775
DOI: 10.1002/pssa.201431888
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“Synthesis, structure and magnetic ordering of the mullite-type Bi2Fe4-xCrxO9 solid solutions with a frustrated pentagonal Cairo lattice”. Rozova MG, Grigoriev VV, Bobrikov IA, Filimonov DS, Zakharov KV, Volkova OS, Vasiliev AN, Antipov EV, Tsirlin AA, Abakumov AM, Journal of the Chemical Society : Dalton transactions 45, 1192 (2016). http://doi.org/10.1039/c5dt04296h
Abstract: Highly homogeneous mullite-type solid solutions Bi2Fe4-xCrxO9 (x = 0.5, 1, 1.2) were synthesized using a soft chemistry technique followed by a solid-state reaction in Ar. The crystal structure of Bi2Fe3CrO9 was investigated using X-ray and neutron powder diffraction, transmission electron microscopy and Fe-57 Mossbauer spectroscopy (S.G. Pbam, a = 7.95579(9) angstrom , b = 8.39145(9) angstrom, c = 5.98242(7) angstrom, R-F(X-ray) = 0.022, R-F(neutron) = 0.057). The ab planes in the structure are tessellated with distorted pentagonal loops built up by three tetrahedrally coordinated Fe sites and two octahedrally coordinated Fe/Cr sites, linked together in the ab plane by corner-sharing forming a pentagonal Cairo lattice. Magnetic susceptibility measurements and powder neutron diffraction show that the compounds order antiferromagnetically (AFM) with the Neel temperatures decreasing upon increasing the Cr content from T-N similar to 250 K for x = 0 to T-N similar to 155 K for x = 1.2. The magnetic structure of Bi2Fe3CrO9 at T = 30 K is characterized by a propagation vector k = (1/2,1/2,1/2). The tetrahedrally coordinated Fe cations form singlet pairs within dimers of corner-sharing tetrahedra, but spins on the neighboring dimers are nearly orthogonal. The octahedrally coordinated (Fe, Cr) cations form antiferromagnetic up-up-down-down chains along c, while the spin arrangement in the ab plane is nearly orthogonal between nearest neighbors and collinear between second neighbors. The resulting magnetic structure is remarkably different from the one in pure Bi2Fe4O9 and features several types of spin correlations even on crystallographically equivalent exchange that may be caused by the simultaneous presence of Fe and Cr on the octahedral site.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 4.029
DOI: 10.1039/c5dt04296h
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“Point defect reactions in silicon studied in situ by high flux electron irradiation in high voltage transmission electron microscope”. Vanhellemont J, Romano Rodriguez A, Fedina L, van Landuyt J, Aseev A, Materials science and technology 11, 1194 (1995). http://doi.org/10.1179/mst.1995.11.11.1194
Abstract: Results are presented of in situ studies of 1 MeV electron irradiation induced (113) defect generation in silicon containing different types and concentrations of extrinsic point defects. A semiquantitative model is developed describing the influence of interfaces and stress fields and of extrinsic point defects on the (113) defect generation in silicon during irradiation. The theoretical results obtained are correlated with experimental data obtained on silicon uniformly doped with boron and phosphorus and with observations obtained by irradiating cross-sectional samples of wafers with highly doped surface layers. It is shown that in situ irradiation in a high voltage election microscope is a powerful tool for studying local point defect reactions in silicon. (C) 1995 The Institute of Materials.
Keywords: A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Impact Factor: 0.995
Times cited: 7
DOI: 10.1179/mst.1995.11.11.1194
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“Point defect reactions in silicon studies in situ by high flux electron irradiation in high voltage transmission electron microscope”. Vanhellemont J, Romano-Rodriguez A, Fedina L, van Landuyt J, Aseev A, Materials science and technology 11, 1194 (1995)
Keywords: A3 Journal article; Electron microscopy for materials research (EMAT)
Times cited: 7
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“Surfactant layers on gold nanorods”. Mosquera J, Wang D, Bals S, Liz-Marzan LM, Accounts of chemical research 56, 1204 (2023). http://doi.org/10.1021/ACS.ACCOUNTS.3C00101
Abstract: Gold nanorods (Au NRs) are an exceptionally promising tool in nanotechnology due to three key factors: (i) their strong interaction with electromagnetic radiation, stemming from their plasmonic nature, (ii) the ease with which the resonance frequency of their longitudinal plasmon mode can be tuned from the visible to the near-infrared region of the electromagnetic spect r u m based on their aspect ratio, and (iii) their simple and cost-effective preparation through seed-mediated chemical growth. In this synthetic method, surfactants play a critical role in controlling the size, shape, and colloidal stabi l i t y of Au NRs. For example, surfactants can stabilize specific crystallographic facets during the formation of Au NRs, leading to t h e formation of NRs with specific morphologies. The process of surfactant adsorption onto the NR surface may result in various assemblies of surfactant molecules, such as spherical micelles, elongated micelles, or bilayers. Again, the assembly mode is critical toward determining the further availabi l i t y of the Au NR surface to the surrounding medium. Despite its importance and a great deal of research effort, the interaction between Au NPs and surfactants remains insufficiently understood, because the assembly process is influenced by numerous factors, including the chemical nature of the surfactant, the surface morphology of Au NPs, and solution parameters. Therefore, gaining a more comprehensive understanding of these interactions is essential to unlock the full potential of the seed-mediated growth method and the applications of plasmonic NPs. A plethora of characterization techniques have been applied to reach such an understanding , but many open questions remain. In this Account, we review the current knowledge on the interactions between surfactants and Au NRs. We briefly introduce the state-of-the-art methods for synthesizing Au NRs and highlight the crucial role of cationic surfactants during this process. The self-assembly and organization of surfactants on the Au NR surface is then discussed to better understand their role in seed-mediated growth. Subsequently, we provide examples and elucidate how chemical additives can be used to modulate micellar assemblies, in turn allowing for a finer control over the growth of Au NRs, including chiral NRs. Next, we review the main experimental characterization and computational modeling techniques that have been applied to shed light on the arrangement of surfactants on Au NRs and summarize the advantages and disadvantages for each technique. The Account ends with a “Conclusions and Outlook” section, outlining promising future research directions and developments that we consider are sti l l required, mostly related to the application of electron microscopy in liquid and in 3D. Finally, we remark on the potential of exploiting machine learning techniques to predict synthetic routes for NPs with predefined structures and properties.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 18.3
Times cited: 8
DOI: 10.1021/ACS.ACCOUNTS.3C00101
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“Investigation of the elementary mechanisms controlling dislocation/twin boundary interactions in fcc metals and alloys : from conventional to advanced TEM characterization”. Idrissi H, Schryvers D Formatex Research Center, S.l., page 1213 (2012).
Keywords: H2 Book chapter; Electron microscopy for materials research (EMAT)
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“Degradation process of lead chromate in paintings by Vincent van Gogh studied by means of synchrotron X-ray spectromicroscopy and related methods : 1 : artificially aged model samples”. Monico L, van der Snickt G, Janssens K, de Nolf W, Miliani C, Verbeeck J, Tian H, Tan H, Dik J, Radepont M, Cotte M, Analytical chemistry 83, 1214 (2011). http://doi.org/10.1021/ac102424h
Abstract: On several paintings by artists of the end of the 19th century and the beginning of the 20th Century a darkening of the original yellow areas, painted with the chrome yellow pigment (PbCrO4, PbCrO4·xPbSO4, or PbCrO4·xPbO) is observed. The most famous of these are the various Sunflowers paintings Vincent van Gogh made during his career. In the first part of this work, we attempt to elucidate the degradation process of chrome yellow by studying artificially aged model samples. In view of the very thin (1−3 μm) alteration layers that are formed, high lateral resolution spectroscopic methods such as microscopic X-ray absorption near edge (μ-XANES), X-ray fluorescence spectrometry (μ-XRF), and electron energy loss spectrometry (EELS) were employed. Some of these use synchrotron radiation (SR). Additionally, microscopic SR X-ray diffraction (SR μ-XRD), μ-Raman, and mid-FTIR spectroscopy were employed to completely characterize the samples. The formation of Cr(III) compounds at the surface of the chrome yellow paint layers is particularly observed in one aged model sample taken from a historic paint tube (ca. 1914). About two-thirds of the chromium that is present at the surface has reduced from the hexavalent to the trivalent state. The EELS and μ-XANES spectra are consistent with the presence of Cr2O3·2H2O (viridian). Moreover, as demonstrated by μ-XANES, the presence of another Cr(III) compound, such as either Cr2(SO4)3·H2O or (CH3CO2)7Cr3(OH)2 [chromium(III) acetate hydroxide], is likely.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Impact Factor: 6.32
Times cited: 113
DOI: 10.1021/ac102424h
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“Ordering principles for tetrahedral chains in Ga- and Co-substituted YBCO intergrowths”. Milat O, Krekels T, Van Tendeloo G, Amelinckx S, Journal de physique: 1: physique générale, physique statistique, matière condensée, domaines interdisciplinaires 3, 1219 (1993)
Abstract: A model for superstructure ordering in the <<chain>> layers of Ga (Co) substituted YBCO intergrowths with general formula (REO2)NSr2MCu2O5 (M = Co, Ga; n = 1, 2, ...) is proposed. By Ga or Co substitution for Cu, the structure of the <<chain>> layer changes : instead of the CuO4 planar squares, the chains consist of MO4 tetrahedra (M = Ga, Co) running along the [110] perovskite direction. The existing model for the Ga substituted <<123>> implies that all the chains are the same. Our new model is based on the results of Electron diffraction and High-resolution electron microscopy investigations. The model reveals the occurrence of two types of chains as a consequence of <<opposite>> ordering between neighbouring tetrahedra. The comer linked tetrahedra in each chain appear as alternatingly rotated in opposite sense, and a chain itself, as being displaced with respect to the underlying structure in one of two senses ; either forth (right) or back (left) along the chain direction. The regular alternation of chains of opposite type doubles the periodicity within a layer and induces the possibility for intrinsic disorder in the chain layer stacking sequence. The planar superstructure and a staggered stacking of the tetrahedral chain layers is found irrespective of the rest of the intergrowth structure. Superstructure ordering in the case of Co substitution is more perfect than for the Ga substitution.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Times cited: 16
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“Surface processes during purification of InP quantum dots”. Mordvinova N, Emelin P, Vinokurov A, Dorofeev S, Abakumov A, Kuznetsova T, Beilstein journal of nanotechnology 5, 1220 (2014). http://doi.org/10.3762/bjnano.5.135
Abstract: Recently, a new simple and fast method for the synthesis of InP quantum dots by using phosphine as phosphorous precursor and myristic acid as surface stabilizer was reported. Purification after synthesis is necessary to obtain samples with good optical properties. Two methods of purification were compared and the surface processes which occur during purification were studied. Traditional precipitation with acetone is accompanied by a small increase in photoluminescence. It occurs that during the purification the hydrolysis of the indium precursor takes place, which leads to a better surface passivation. The electrophoretic purification technique does not increase luminescence efficiency but yields very pure quantum dots in only a few minutes. Additionally, the formation of In(OH)(3) during the low temperature synthesis was explained. Purification of quantum dots is a very significant part of post-synthetical treatment that determines the properties of the material. But this subject is not sufficiently discussed in the literature. The paper is devoted to the processes that occur at the surface of quantum dots during purification. A new method of purification, electrophoresis, is investigated and described in particular.
Keywords: A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Impact Factor: 3.127
Times cited: 5
DOI: 10.3762/bjnano.5.135
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“Melamine–Formaldehyde Microcapsules: Micro- and Nanostructural Characterization with Electron Microscopy”. Heidari H, Rivero G, Idrissi H, Ramachandran D, Cakir S, Egoavil R, Kurttepeli M, Crabbé, AC, Hauffman T, Terryn H, Du Prez F, Schryvers D, Microscopy and microanalysis 22, 1222 (2016). http://doi.org/10.1017/S1431927616012484
Abstract: A systematic study has been carried out to compare the surface morphology, shell thickness, mechanical properties, and binding behavior of melamine–formaldehyde microcapsules of 5–30 μm diameter size with various amounts of core content by using scanning and transmission electron microscopy including electron tomography, in situ nanomechanical tensile testing, and electron energy-loss spectroscopy. It is found that porosities are present on the outside surface of the capsule shell, but not on the inner surface of the shell. Nanomechanical tensile tests on the capsule shells reveal that Young’s modulus of the shell material is higher than that of bulk melamine–formaldehyde and that the shells exhibit a larger fracture strain compared with the bulk. Core-loss elemental analysis of microcapsules embedded in epoxy indicates that during the curing process, the microcapsule-matrix interface remains uniform and the epoxy matrix penetrates into the surface micro-porosities of the capsule shells.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 1.891
Times cited: 2
DOI: 10.1017/S1431927616012484
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“Stable polyoxometalate insertion within the mesoporous metal organic framework MIL-100(Fe)”. Canioni R, Roch-Marchal C, Sécheresse F, Horcajada P, Serre C, Hardi-Dan M, Férey G, Grenèche J-M, Lefebvre F, Chang J-S, Hwang Y-K, Lebedev O, Turner S, Van Tendeloo G, Journal of materials chemistry 21, 1226 (2011). http://doi.org/10.1039/c0jm02381g
Abstract: Successful encapsulation of polyoxometalate (POM) within the framework of a mesoporous iron trimesate MIL-100(Fe) sample has been achieved by direct hydrothermal synthesis in the absence of fluorine. XRPD, 31P MAS NMR, IR, EELS, TEM and 57Fe Mössbauer spectrometry corroborate the insertion of POM within the cavities of the MOF. The experimental Mo/Fe ratio is 0.95, in agreement with the maximum theoretical amount of POM loaded within the pores of MIL-100(Fe), based on steric hindrance considerations. The POM-MIL-100(Fe) sample exhibits a pore volume of 0.373 cm3 g−1 and a BET surface area close to 1000 m2 g−1, indicating that small gas molecules can easily diffuse inside the cavities despite the presence of heavy phosphomolybdates. These latter contribute to the decrease in the overall surface area, due to the increase in molar weight, by 65%. Moreover, the resulting Keggin containing MIL-100(Fe) solid is stable in aqueous solution with no POM leaching even after more than 2 months. In addition, no exchange of the Keggin anions by tetrabutylammonium perchlorate in organic media has been observed.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Times cited: 158
DOI: 10.1039/c0jm02381g
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“Hierarchical zeolite single-crystal reactor for excellent catalytic efficiency”. Sun M-H, Zhou J, Hu Z-Y, Chen L-H, Li L-Y, Wang Y-D, Xie Z-K, Turner S, Van Tendeloo G, Hasan T, Su B-L, Matter 3, 1226 (2020). http://doi.org/10.1016/J.MATT.2020.07.016
Abstract: As a size- and shape-selective catalyst, zeolites are widely used in petroleum and fine-chemicals processing. However, their small micropores severely hinder molecular diffusion and are sensitive to coke formation. Hierarchically porous zeolite single crystals with fully interconnected, ordered, and tunable multimodal porosity at macro-, meso-, and microlength scale, like in leaves, offer the ideal solution. However, their synthesis remains highly challenging. Here, we report a versatile confined zeolite crystallization process to achieve these superior properties. Such zeolite single crystals lead to significantly improved mass transport properties by shortening the diffusion length while maintaining shape-selective properties, endowing them with a high efficiency of zeolite crystals, enhanced catalytic activities and lifetime, highly reduced coke formation, and reduced deactivation rate in bulky-molecule reactions and methanol-to-olefins process. Their industrial utilization can lead to the design of innovative and intensified reactors and processes with highly enhanced efficiency and minimum energy consumption.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
DOI: 10.1016/J.MATT.2020.07.016
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“The notion of resolution”. Van Aert S, den Dekker AJ, van Dyck D, van den Bos A Springer, Berlin, page 1228 (2008).
Keywords: H3 Book chapter; Electron microscopy for materials research (EMAT); Vision lab
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“The notion of resolution”. Van Aert S, den Dekker AJ, van Dyck D, van den Bos A Springer, Berlin, page 1228 (2007).
Keywords: H3 Book chapter; Electron microscopy for materials research (EMAT); Vision lab
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“Quantum transport in a nanosize silicon-on-insulator metal-oxide-semiconductor field effect transistor”. Croitoru MD, Gladilin VN, Fomin VM, Devreese JT, Magnus W, Schoenmaker W, Sorée B, Journal of applied physics 93, 1230 (2003). http://doi.org/10.1063/1.1533108
Keywords: A1 Journal article; Theory of quantum systems and complex systems; Condensed Matter Theory (CMT); Electron microscopy for materials research (EMAT)
Impact Factor: 2.068
Times cited: 16
DOI: 10.1063/1.1533108
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“Off-stoichiometry effects on the crystalline and defect structure of hexagonal manganite REMnO3 films (RE = Y, Er, Dy)”. Gélard J, Jehanathan N, Roussel H, Gariglio S, Lebedev OI, Van Tendeloo G, Dubourdieu C, Chemistry of materials 23, 1232 (2011). http://doi.org/10.1021/cm1029358
Abstract: The crystalline and defect structure of epitaxial hexagonal RExMnyO3 (RE = Er, Dy) films with varying cationic composition was investigated by X-ray diffraction and transmission electron microscopy. The films are composed of a strained layer at the interface with the substrate and of a relaxed layer on top of it. The critical thickness is of 10 to 25 nm. For Mn-rich films (or RE deficient), an off-stoichiometric composition maintaining the hexagonal LuMnO3-type structure is stabilized over a large range of the RE/Mn ratio (0.72−1.00), with no Mn-rich secondary phases observed. A linear dependence of the out-of-plane lattice parameter with RE/Mn is observed in this range. Out-of-phase boundary (OPB) extended defects are observed in all films and exhibit a local change in stoichiometry. Such a large solubility limit in the RE deficient region points toward the formation of vacancies on the RE site (RExMnO3−δ, with 0.72 ≤ x < 1), a phenomenon that is encountered in perovskite manganites such as LaxMnO3−δ (x < 1) and that may strongly impact the physical properties of hexagonal manganites.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 9.466
Times cited: 17
DOI: 10.1021/cm1029358
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“Effects of Nanostructure and Coating on the Mechanics of Carbon Nanotube Arrays”. Poelma RH, Fan X, Hu Z-Y, Van Tendeloo G, van Zeijl HW, Zhang GQ, Advanced functional materials 26, 1233 (2016). http://doi.org/10.1002/adfm.201503673
Abstract: Nanoscale materials are one of the few engineering materials that can be grown from the bottom up in a controlled manner. Here, the effects of nanostructure and nanoscale conformal coating on the mechanical behavior of vertically aligned carbon nanotube (CNT) arrays through experiments and simulation are systematically investigated. A modeling approach is developed and used to quantify the compressive strength and modulus of the CNT array under large deformation. The model accounts for the porous
nanostructure, which contains multiple CNTs with random waviness, van der Waals interactions, fracture strain, contacts, and frictional forces. CNT array micropillars are grown and their porous nanostructure is controlled by the infi ltration and deposition of thin conformal coatings using chemical vapor deposition. Flat-punch nanoindentation experiments reveal signifi cant changes in material properties as a function of coating thickness. The simulations explain the experimental results and show the novel failure transition regime that changes from collective CNT buckling toward structural collapse due to fracture. The compressive strength and the elastic
modulus increase exponentially as a function of the coating thickness and demonstrate a unique dependency on the CNT waviness. More interestingly, a design rule is identifi ed that predicts the optimum coating thickness for porous materials.
Keywords: A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Impact Factor: 12.124
Times cited: 17
DOI: 10.1002/adfm.201503673
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“HREM investigation of martensite precursor effects and stacking sequences in Ni-Mn-Ti alloys”. Schryvers D, Lahjouji DE, Slootmaekers B, Potapov PL, Scripta metallurgica et materialia 35, 1235 (1996). http://doi.org/10.1016/1359-6462(96)00271-0
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.224
Times cited: 2
DOI: 10.1016/1359-6462(96)00271-0
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“Quantitative atomic resolution mapping using high-angle annular dark field scanning transmission electron microscopy”. Van Aert S, Verbeeck J, Erni R, Bals S, Luysberg M, van Dyck D, Van Tendeloo G, Ultramicroscopy 109, 1236 (2009). http://doi.org/10.1016/j.ultramic.2009.05.010
Abstract: A model-based method is proposed to relatively quantify the chemical composition of atomic columns using high angle annular dark field (HAADF) scanning transmission electron microscopy (STEM) images. The method is based on a quantification of the total intensity of the scattered electrons for the individual atomic columns using statistical parameter estimation theory. In order to apply this theory, a model is required describing the image contrast of the HAADF STEM images. Therefore, a simple, effective incoherent model has been assumed which takes the probe intensity profile into account. The scattered intensities can then be estimated by fitting this model to an experimental HAADF STEM image. These estimates are used as a performance measure to distinguish between different atomic column types and to identify the nature of unknown columns with good accuracy and precision using statistical hypothesis testing. The reliability of the method is supported by means of simulated HAADF STEM images as well as a combination of experimental images and electron energy-loss spectra. It is experimentally shown that statistically meaningful information on the composition of individual columns can be obtained even if the difference in averaged atomic number Z is only 3. Using this method, quantitative mapping at atomic resolution using HAADF STEM images only has become possible without the need of simultaneously recorded electron energy loss spectra.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab
Impact Factor: 2.843
Times cited: 166
DOI: 10.1016/j.ultramic.2009.05.010
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