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“From Bi4V2O11 to Bi4V2O10.66: the VV-VIV transformation in the Aurovillius-type framework”. Huvé, M, Vannier R-N, Nowogrocki G, Mairesse G, Van Tendeloo G, Journal of materials chemistry 6, 1339 (1996). http://doi.org/10.1039/jm9960601339
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Times cited: 63
DOI: 10.1039/jm9960601339
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“Diagnostic mirrors with transparent protection layer for ITER”. Razdobarin AG, Mukhin EE, Semenov VV, Tolstyakov SY, Kochergin MM, Kurskiev GS, Podushnikova KA, Kirilenko DA, Sitnikova AA, Konovalov VG, Solodovchenko SI, Nekhaieva OM, Skorik OA, Bondarenko VN, Voitsenya VS;, Fusion engineering and design 86, 1341 (2011). http://doi.org/10.1016/j.fusengdes.2011.02.052
Abstract: Fast degradation of in-vessel optics is one of the most serious problems for all optical diagnostics in ITER. To provide the resistance to mechanical and thermal stresses along with a high stability of optical characteristics under deposition-dominated conditions we suggest using high-reflective metallic (Ag or Al) film mirrors coated on silicon substrate and protected with thin oxide film in the divertor Thomson Scattering (TS) diagnostics. The mirrors coated with Al2O3 and ZrO2 films were tested under irradiation by deuterium ions. The experimental results on the oxide films sputtering are discussed in the context of their applicability for the first mirror protection in ITER.
Keywords: A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Impact Factor: 1.319
Times cited: 6
DOI: 10.1016/j.fusengdes.2011.02.052
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“Deconvolution of core electron energy loss spectra”. Verbeeck J, Bertoni G, Ultramicroscopy 109, 1343 (2009). http://doi.org/10.1016/j.ultramic.2009.06.010
Abstract: Different deconvolution methods for removing multiple scattering and instrumental broadening from core loss electron energy loss spectra are compared with special attention to the artefacts they introduce. The Gaussian modifier method, Wiener filter, maximum entropy, and model based methods are described. Their performance is compared on virtual spectra where the true single scattering distribution is known. A test on experimental spectra confirms the good performance of model based deconvolution in comparison to maximum entropy methods and shows the advantage of knowing the estimated error bars from a single spectrum acquisition.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 2.843
Times cited: 13
DOI: 10.1016/j.ultramic.2009.06.010
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“Synthesis of single wall carbon nanotubes by catalytic decomposition of hydrocarbons”. Colomer J-F, Bister G, Willems I, Konya Z, Fonseca A, Van Tendeloo G, Nagy JB, Chemical communications , 1343 (1999). http://doi.org/10.1039/a903142a
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 6.319
Times cited: 110
DOI: 10.1039/a903142a
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“Synthesis and characterization of La1+xSr2-xCoMnO7-\delta (x=0,0.2, \delta=0,1)”. El Shinawi H, Bertha A, Hadermann J, Herranz T, Santos B, Marco JF, Berry FJ, Greaves C, Journal of solid state chemistry 183, 1347 (2010). http://doi.org/10.1016/j.jssc.2010.04.018
Abstract: The n=2 Ruddlesden-Popper phases LaSr(2)CoMnO(7) and La(1 2)Sr(1 8)CoMnO(7) have been synthesized by a sol-gel method The O6-type phases LaSr(2)CoMnO(6) and La(1 2)Sr(1 8)CoMnO(6) were produced by reduction of the 07 phases under a hydrogen atmosphere The materials crystallize in the tetragonal I4/mmm space group with no evidence of long-range cation order in the neutron and electron diffraction data Oxygen vacancies in the reduced materials are located primarily at the common apex of the double perovskite layers giving rise to square pyramidal coordination around cobalt and manganese ions. The oxidation states Co(3+)/Mn(4+) and Co(2+)/Mn(3+) predominate in the as-prepared and reduced materials, respectively The materials are spin glasses at low temperature and the dominant magnetic interactions change from ferro- to antiferromagnetic following reduction (C) 2010 Elsevier Inc All rights reserved
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 2.299
Times cited: 5
DOI: 10.1016/j.jssc.2010.04.018
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“A method to determine the local surface profile from reconstructed exit waves”. Wang A, Chen FR, Van Aert S, van Dyck D, Ultramicroscopy 111, 1352 (2011). http://doi.org/10.1016/j.ultramic.2011.04.005
Abstract: Reconstructed exit waves are useful to quantify unknown structure parameters such as the position and composition of the atom columns at atomic scale. Existing techniques provide a complex wave in a flat plane which is close to the plane where the electrons leave the atom columns. However, due to local deviation in the flatness of the exit surface, there will be an offset between the plane of reconstruction and the actual exit of a specific atom column. Using the channelling theory, it has been shown that this defocus offset can in principle be determined atom column-by-atom column. As such, the surface roughness could be quantified at atomic scale. However, the outcome strongly depends on the initial plane of reconstruction especially in a crystalline structure. If this plane is further away from the true exit, the waves of the atom columns become delocalized and interfere mutually which strongly complicates the interpretation of the exit wave in terms of the local structure. In this paper, we will study the delocalization with defocus using the channelling theory in a more systematic way.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab
Impact Factor: 2.843
Times cited: 3
DOI: 10.1016/j.ultramic.2011.04.005
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“The influence of the h-BN morphology and structure on the c-BN growth”. Nistor L, Teodorescu V, Ghica C, van Landuyt J, Dinca G, Georgeoni P, Diamond and related materials
T2 –, 11th European Conference on Diamond, Diamond-like Materials, Carbon, Nanotubes, Nitrides and Silicon Carbide (Diamond 2000), SEP 03-08, 2000, OPORTO, PORTUGAL 10, 1352 (2001). http://doi.org/10.1016/S0925-9635(00)00377-0
Abstract: The morphology and structure of hexagonal graphitic BN (h-BN) powders with graphitization indices GI <5, used as precursors for the synthesis of cubic BN (c-BN) crystals, has been investigated by transmission electron microscopy in diffraction contrast and high resolution. We show that besides the GI, which is a general parameter for controlling the structural quality of h-EN ponders, some other microstructural features strongly influence the synthesis of c-BN. In our opinion, the high reactivity of some h-BN powders results from the presence of some nucleation centers for c-BN, observed at the edges of the h-BN particles. They are formed by a rearrangement of the graphitic (0002) planes by bending back, joining in pairs and forming locally nanoarches (half nanotubes). In these particular places, the nature of bonding locally turns towards sp(3), as in the case of c-BN, (C) 2001 Elsevier Science B.V. All rights reserved.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 2.561
Times cited: 17
DOI: 10.1016/S0925-9635(00)00377-0
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“TEM sample preparation by FIB for carbon nanotube interconnects”. Ke X, Bals S, Romo Negreira A, Hantschel T, Bender H, Van Tendeloo G, Ultramicroscopy 109, 1353 (2009). http://doi.org/10.1016/j.ultramic.2009.06.011
Abstract: A powerful method to study carbon nanotubes (CNTs) grown in patterned substrates for potential interconnects applications is transmission electron microscopy (TEM). However, high-quality TEM samples are necessary for such a study. Here, TEM specimen preparation by focused ion beam (FIB) has been used to obtain lamellae of patterned samples containing CNTs grown inside contact holes. A dual-cap Pt protection layer and an extensive 5 kV cleaning procedure are applied in order to preserve the CNTs and avoid deterioration during milling. TEM results show that the inner shell structure of the carbon nanotubes has been preserved, which proves that focused ion beam is a useful technique to prepare TEM samples of CNT interconnects.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 2.843
Times cited: 21
DOI: 10.1016/j.ultramic.2009.06.011
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“One-pot synthesis of catalytically stable and active nanoreactors: encapsulation of size-controlled nanoparticles within a hierarchically macroporous core@ordered mesoporous shell system”. Yang X-Y, Li Y, Van Tendeloo G, Xiao F-S, Su B-L, Advanced materials 21, 1368 (2009). http://doi.org/10.1002/adma.200802914
Abstract: Size-controlled, catalytically active nanoparticles are successfully encapsulated in a one-pot synthesis to form novel hierarchical macroporous core@mesoporous shell structures, where macroporous cores are connected by uniform and ordered mesoporous channels. Most importantly, the encapsulated nanoparticles can be used as nanoreactors, with high activities and excellent long-term recycling stability.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 19.791
Times cited: 61
DOI: 10.1002/adma.200802914
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“Bifunctional nickel-nitrogen-doped-carbon-supported copper electrocatalyst for CO2 reduction”. Choukroun D, Daems N, Kenis T, Van Everbroeck T, Hereijgers J, Altantzis T, Bals S, Cool P, Breugelmans T, Journal Of Physical Chemistry C 124, 1369 (2020). http://doi.org/10.1021/ACS.JPCC.9B08931
Abstract: Bifunctionality is a key feature of many industrial catalysts, supported metal clusters and particles in particular, and the development of such catalysts for the CO2 reduction reaction (CO2RR) to hydrocarbons and alcohols is gaining traction in light of recent advancements in the field. Carbon-supported Cu nanoparticles are suitable candidates for integration in the state-of-the-art reaction interfaces, and here, we propose, synthesize, and evaluate a bifunctional Ni–N-doped-C-supported Cu electrocatalyst, in which the support possesses active sites for selective CO2 conversion to CO and Cu nanoparticles catalyze either the direct CO2 or CO reduction to hydrocarbons. In this work, we introduce the scientific rationale behind the concept, its applicability, and the challenges with regard to the catalyst. From the practical aspect, the deposition of Cu nanoparticles onto carbon black and Ni–N–C supports via an ammonia-driven deposition precipitation method is reported and explored in more detail using X-ray diffraction, thermogravimetric analysis, and hydrogen temperature-programmed reduction. High-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) and energy-dispersive X-ray spectroscopy (EDXS) give further evidence of the presence of Cu-containing nanoparticles on the Ni–N–C supports while revealing an additional relationship between the nanoparticle’s composition and the electrode’s electrocatalytic performance. Compared to the benchmark carbon black-supported Cu catalysts, Ni–N–C-supported Cu delivers up to a 2-fold increase in the partial C2H4 current density at −1.05 VRHE (C1/C2 = 0.67) and a concomitant 10-fold increase of the CO partial current density. The enhanced ethylene production metrics, obtained by virtue of the higher intrinsic activity of the Ni–N–C support, point out toward a synergistic action between the two catalytic functionalities.
Keywords: A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA); Applied Electrochemistry & Catalysis (ELCAT)
Impact Factor: 3.7
Times cited: 24
DOI: 10.1021/ACS.JPCC.9B08931
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“Long-range orientation and atomic attachment of nanocrystals in 2D honeycomb superlattices”. Boneschanscher MP, Evers WH, Geuchies JJ, Altantzis T, Goris B, Rabouw FT, van Rossum SAP, van der Zant HSJ, Siebbeles LDA, Van Tendeloo G, Swart I, Hilhorst J, Petukhov AV, Bals S, Vanmaekelbergh D;, Science 344, 1377 (2014). http://doi.org/10.1126/science.1252642
Abstract: Oriented attachment of synthetic semiconductor nanocrystals is emerging as a route for obtaining new semiconductors that can have Dirac-type electronic bands like graphene, but also strong spin-orbit coupling. The two-dimensional assembly geometry will require both atomic coherence and long-range periodicity of the superlattices. We show how the interfacial self-assembly and oriented attachment of nanocrystals results in two-dimensional (2D) metal chalcogenide semiconductors with a honeycomb superlattice. We present an extensive atomic and nanoscale characterization of these systems using direct imaging and wave scattering methods. The honeycomb superlattices are atomically coherent, and have an octahedral symmetry that is buckled; the nanocrystals occupy two parallel planes. Considerable necking and large-scale atomic motion occurred during the attachment process.
Keywords: A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Impact Factor: 37.205
Times cited: 304
DOI: 10.1126/science.1252642
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“Local oxygen-vacancy ordering and twinned octahedral tilting pattern in the Bi0.81Pb0.19FeO2.905 cubic perovskite”. Dachraoui W, Hadermann J, Abakumov AM, Tsirlin AA, Batuk D, Glazyrin K, McCammon C, Dubrovinsky L, Van Tendeloo G, Chemistry of materials 24, 1378 (2012). http://doi.org/10.1021/cm300178x
Abstract: The structure of Bi0.81Pb0.19FeO2.905 was investigated on different length scales using a combination of electron diffraction, high-resolution scanning transmission electron microscopy, synchrotron X-ray powder diffraction, and Mössbauer spectroscopy. In the 80300 K temperature range, the average crystal structure of Bi0.81Pb0.19FeO2.905 is a cubic Pm3̅m perovskite with a = 3.95368(3) Å at T = 300 K. The (Pb2+, Bi3+) cations and O2 anions are randomly displaced along the 110 cubic directions, indicating the steric activity of the lone pair on the Pb2+ and Bi3+ cations and a tilting distortion of the perovskite framework. The charge imbalance induced by the heterovalent Bi3+ → Pb2+ substitution is compensated by the formation of oxygen vacancies preserving the trivalent state of the Fe cations. On a short scale, oxygen vacancies are located in anion-deficient (FeO1.25) layers that are approximately 6 perovskite unit cells apart and transform every sixth layer of the FeO6 octahedra into a layer with a 1:1 mixture of corner-sharing FeO4 tetrahedra and FeO5 tetragonal pyramids. The anion-deficient layers act as twin planes for the octahedral tilting pattern of adjacent perovskite blocks. They effectively randomize the octahedral tilting and prevent the cooperative distortion of the perovskite framework. The disorder in the anion sublattice impedes cooperative interactions of the local dipoles induced by the off-center displacements of the Pb and Bi cations. Magnetic susceptibility measurements evidence the antiferromagnetic ordering in Bi0.81Pb0.19FeO2.905 at low temperatures.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 9.466
Times cited: 27
DOI: 10.1021/cm300178x
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“Polyethylene glycol conjugated polymeric nanocapsules for targeted delivery of quercetin to folate-expressing cancer cells in vitro and in vivo”. El-Gogary RI, Rubio N, Wang JTW, Al-Jamal WT, Bourgognon M, Kafa H, Naeem M, Klippstein R, Abbate V, Leroux F, Bals S, Van Tendeloo G, Kamel AO, Awad GAS, Mortada ND, Al-Jamal KT;, ACS nano 8, 1384 (2014). http://doi.org/10.1021/nn405155b
Abstract: In this work we describe the formulation and characterization of chemically modified polymeric nanocapsules incorporating the anticancer drug, quercetin, for the passive and active targeting to tumors. Folic acid was conjugated to poly(lactide-co-glycolide) (PLGA) polymer to facilitate active targeting to cancer cells. Two different methods for the conjugation of PLGA to folic acid were employed utilizing polyethylene glycol (PEG) as a spacer. Characterization of the conjugates was performed using FTIR and H-1 NMR studies. The PEG and folk acid content was independent of the conjugation methodology employed. PEGylation has shown to reduce the size of the nanocapsule; moreover, zeta-potential was shown to be polymer-type dependent. Comparative studies on the cytotoxicity and cellular uptake of the different formulations by He La cells, in the presence and absence of excess folic acid, were carried out using MTT assay and Confocal Laser Scanning Microscopy, respectively. Both results confirmed the selective uptake and cytotoxicity of the folic acid targeted nanocapsules to the folate enriched cancer cells in a folate-dependent manner. Finally, the passive tumor accumulation and the active targeting of the nanocapsules to folate-expressing cells were confirmed upon intravenous administration in He La or IGROV-1 tumor-bearing mice. The developed nanocapsules provide a system for targeted delivery of a range of hydrophobic anticancer drugs in vivo.
Keywords: A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Impact Factor: 13.942
Times cited: 144
DOI: 10.1021/nn405155b
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“Copper(II)-binding ability of stereoisomeric cis- and trans-2-aminocyclohexanecarboxylic acidl-phenylalanine dipeptides : a combined CW/pulsed EPR and DFT study”. Nagy NV, Van Doorslaer S, Szabó-Plánka T, Van Rompaey S, Hamza A, Fülöp F, Tóth GK, Rockenbauer A, Inorganic chemistry 51, 1386 (2012). http://doi.org/10.1021/ic2016116
Abstract: With the aim of an improved understanding of the metal-complexation properties of alicyclic β-amino acid stereoisomers, and their peptides, the complex equilibria and modes of coordination with copper(II) of l-phenylalanine (F) derivatives of cis/trans-2-aminocyclohexanecarboxylic acid (c/tACHC), i.e. the dipeptides F-c/tACHC and c/tACHC-F, were investigated by a combination of CW and pulsed EPR methods. For the interpretation of the experimental data, DFT quantum-chemical calculations were carried out. Simulation of a pH-dependent series of room-temperature CW-EPR spectra revealed the presence of EPR-active complexes ([Cu(aqua)]2+, [CuL]+, [CuLH1], [CuLH2]−, and [CuL2H1]−), and an EPR-inactive species ([Cu2L2H3]−) in aqueous solutions for all studied cases. [CuLH]2+ was included in the equilibrium model for the c/tACHC-Fcopper(II) systems, and [CuL2], together with two coordination isomers of [CuL2H1]−, were also identified in the F-tACHCcopper(II) system. Comparison of the complexation properties of the diastereomeric ligand pair F-(1S,2R)-ACHC and F-(1R,2S)-ACHC did not reveal significant differences. Considerably lower formation constants were obtained for the trans than for the cis isomers for both the F-c/tACHC and the c/tACHC-F pairs in the case of [CuLH1] involving tridentate coordination by the amino, the deprotonated peptide, and the carboxylate groups. A detailed structural analysis by pulsed EPR methods and DFT calculations indicated that there was no significant destabilization for the complexes of the trans isomers. The lower stability of their complexes was explained by the limitation that only the conformer with donor groups in equatorialequatorial ring positions can bind to copper(II), whereas both equatorial-axial conformers of the cis isomers are capable of binding. From a consideration of the proton couplings obtained with X-band 1H HYSCORE, 2H exchange experiments, and DFT, the thermodynamically most stable cyclohexane ring conformer was assigned for all four [CuLH1] complexes. For the F-cACHC case, the conformer did not match the most stable conformer of the free ligand.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 4.857
Times cited: 18
DOI: 10.1021/ic2016116
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“Seedless synthesis of single crystalline Au nanoparticles with unusual shapes and tunable LSPR in the near-IR”. Angelomé, PC, Heidari Mezerji H, Goris B, Pastoriza-Santos I, Pérez-Juste J, Bals S, Liz-Marzán LM, Chemistry of materials 24, 1393 (2012). http://doi.org/10.1021/cm3004479
Abstract: The plasmonic properties of metal nanoparticles have acquired great importance because of their potential applications in very diverse fields. Metal nanoparticles with localized surface plasmon resonances (LSPR) in the near-infrared (NIR, 7501300 nm) are of particular interest because tissues, blood, and water display low absorption in this spectral range, thus facilitating biomedical applications. Cetyltrimethylammonium chloride (CTAC) was used to induce the seedless formation of highly anisotropic, twisted single crystalline Au nanoparticles in a single step. The LSPR of the obtained particles can be tuned from 600 nm up to 1400 nm by simply changing the reaction temperature or the reagents concentrations. The tunability of the LSPR is closely associated with significant changes in the final particle morphology, which was studied by advanced electron microscopy techniques (3D Tomography and HAADF-STEM). Kinetic experiments were carried out to establish the growth mechanism, suggesting that slow kinetics together with the complexation of the gold salt precursor to CTAC are key factors favoring the formation of these anisotropic particles.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 9.466
Times cited: 42
DOI: 10.1021/cm3004479
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“Mixed tellurides Ni3-xGaTe2 (0\leq x\leq0.65): crystal and electronic structures, properties, and nickel deficiency effects on vacancy ordering”. Isaeva AA, Makarevich ON, Kutznetsov AN, Doert T, Abakumov AM, Van Tendeloo G, European journal of inorganic chemistry , 1395 (2010). http://doi.org/10.1002/ejic.200901027
Abstract: The Ni3-xGaTe2 series of compounds (0 x 0.65) was synthesized by a high-temperature ceramic technique at 750 °C. Crystal structures of three compounds in the series were determined by X-ray powder diffraction: Ni2.98(1)GaTe2 (RI = 0.042, Rp = 0.023, Rwp = 0.035), Ni2.79(1)GaTe2 (RI = 0.053, Rp = 0.028, Rwp = 0.039), Ni2.58(1)GaTe2 (RI = 0.081, Rp = 0.037, Rwp = 0.056); the structures were verified by electron diffraction and, for the former compound, high-resolution electron microscopy. The compounds crystallize in a hexagonal lattice with P63/mmc, and the structures can be regarded as a hexagonal close-packed array with a -Ga-Te-Te- stacking sequence. The octahedral and trigonal bipyramidal voids in the hcp structure are selectively filled with Ni atoms to form one entirely occupied and two partially occupied sites, thus allowing variations in the nickel content in the series of compounds Ni3-xGaTe2 (0 x 0.65). A superstructure with asup = 2asub (P63/mmc) has been identified for Ni3-xGaTe2 (0.5 x 0.65) by electron diffraction. Real-space, high-resolution images confirm an ordering of Ni atoms and vacancies inthe ab plane. Quantum-chemical calculations performed forNi3-xGaTe2 (x = 0, 0.25, 0.75, 1) suggest anisotropic metallic conductivity and Pauli paramagnetic behavior that are experimentally confirmed for Ni3GaTe2.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 2.444
Times cited: 8
DOI: 10.1002/ejic.200901027
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“New molybdenum oxides Ag4M2Zr(MoO4)6 (M=Mg, Mn, Co, Zn) with a channel-like structure”. Khobrakova ET, Morozov VA, Khasanov SS, Tsyrenova GD, Khaikina EG, Lebedev OI, Van Tendeloo G, Lazoryak BI, Solid state sciences 7, 1397 (2005). http://doi.org/10.1016/j.solidstatesciences.2005.08.010
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 1.811
Times cited: 9
DOI: 10.1016/j.solidstatesciences.2005.08.010
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“Oxygen and fluorine doping in Sr2MnGaO5 brownmillerite”. Antipov EV, Abakumov AM, Alekseeva AM, Rozova MG, Hadermann J, Lebedev OI, Van Tendeloo G, Physica status solidi: A: applied research 201, 1403 (2004). http://doi.org/10.1002/pssa.200304428
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Times cited: 9
DOI: 10.1002/pssa.200304428
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“Linear versus non-linear structural information limit in high-resolution transmission electron microscopy”. Van Aert S, Chen JH, van Dyck D, Ultramicroscopy 110, 1404 (2010). http://doi.org/10.1016/j.ultramic.2010.07.001
Abstract: A widely used performance criterion in high-resolution transmission electron microscopy (HRTEM) is the information limit. It corresponds to the inverse of the maximum spatial object frequency that is linearly transmitted with sufficient intensity from the exit plane of the object to the image plane and is limited due to partial temporal coherence. In practice, the information limit is often measured from a diffractogram or from Young's fringes assuming a weak phase object scattering beyond the inverse of the information limit. However, for an aberration corrected electron microscope, with an information limit in the sub-angstrom range, weak phase objects are no longer applicable since they do not scatter sufficiently in this range. Therefore, one relies on more strongly scattering objects such as crystals of heavy atoms observed along a low index zone axis. In that case, dynamical scattering becomes important such that the non-linear and linear interaction may be equally important. The non-linear interaction may then set the experimental cut-off frequency observed in a diffractogram. The goal of this paper is to quantify both the linear and the non-linear information transfer in terms of closed form analytical expressions. Whereas the cut-off frequency set by the linear transfer can be directly related with the attainable resolution, information from the non-linear transfer can only be extracted using quantitative, model-based methods. In contrast to the historic definition of the information limit depending on microscope parameters only, the expressions derived in this paper explicitly incorporate their dependence on the structure parameters as well. In order to emphasize this dependence and to distinguish from the usual information limit, the expressions derived for the inverse cut-off frequencies will be referred to as the linear and non-linear structural information limit. The present findings confirm the well-known result that partial temporal coherence has different effects on the transfer of the linear and non-linear terms, such that the non-linear imaging contributions are damped less than the linear imaging contributions at high spatial frequencies. This will be important when coherent aberrations such as spherical aberration and defocus are reduced.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab
Impact Factor: 2.843
Times cited: 6
DOI: 10.1016/j.ultramic.2010.07.001
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“Theoretical investigation of grain size tuning during prolonged bias-enhanced nucleation”. Eckert M, Mortet V, Zhang L, Neyts E, Verbeeck J, Haenen ken, Bogaerts A, Chemistry of materials 23, 1414 (2011). http://doi.org/10.1021/cm102481y
Abstract: In this paper, the effects of prolonged bias-enhanced nucleation (prolonged BEN) on the growth mechanisms of diamond are investigated by molecular dynamics (MD) and combined MD-Metropolis Monte Carlo (MD-MMC) simulations. First, cumulative impacts of CxHy+ and Hx+ on an a-C:H/nanodiamond composite were simulated; second, nonconsecutive impacts of the dominant ions were simulated in order to understand the observed phenomena in more detail. As stated in the existing literature, the growth of diamond structures during prolonged BEN is a process that takes place below the surface of the growing film. The investigation of the penetration behavior of CxHy+ and Hx+ species shows that the carbon-containing ions remain trapped within this amorphous phase where they dominate mechanisms like precipitation of sp3 carbon clusters. The H+ ions, however, penetrate into the crystalline phase at high bias voltages (>100 V), destroying the perfect diamond structure. The experimentally measured reduction of grain sizes at high bias voltage, reported in the literature, might thus be related to penetrating H+ ions. Furthermore, the CxHy+ ions are found to be the most efficient sputtering agents, preventing the build up of defective material.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 9.466
Times cited: 9
DOI: 10.1021/cm102481y
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“Nano-structures at martensite macrotwin interfaces in Ni65Al35”. Boullay P, Schryvers D, Ball JM, Acta materialia 51, 1421 (2003). http://doi.org/10.1016/S1359-6454(02)00536-0
Abstract: The atomic configurations at macrotwin interfaces between microtwinned martensite plates in Ni65Al35 material are investigated using transmission electron microscopy. The observed structures are interpreted in view of possible formation mechanisms for these interfaces. A distinction is made between cases in which the microtwins, originating from mutually perpendicular {110} austenite planes, enclose a final angle larger or smaller than 90degrees. Two different configurations, a crossing and a step type are described. Depending on the actual case, tapering, bending and tip splitting of the smaller microtwinvariants are observed. The most reproducible deformations occur in a region of approximately 5-10 nm width around the interface while a variety of structural defects are observed further away from the interface. These structures and deformations are interpreted in terms of the coalescence of two separately nucleated microtwinned martensite plates and the need to accommodate remaining stresses. (C) 2003 Acta Materialia Inc. Published by Elsevier Science Ltd. All rights reserved.
Keywords: A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Impact Factor: 5.301
Times cited: 31
DOI: 10.1016/S1359-6454(02)00536-0
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“Effect of amorphous-crystalline interfaces on the martensitic transformation in Ti50Ni25Cu25”. Santamarta R, Schryvers D, Scripta materialia 50, 1423 (2004). http://doi.org/10.1016/j.scriptamat.2004.03.013
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.747
Times cited: 29
DOI: 10.1016/j.scriptamat.2004.03.013
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“Y2O3 inclusions in YBa2Cu3O7-\delta thin films”. Verbist K, Vasiliev AL, Van Tendeloo G, Applied physics letters 66, 1424 (1995). http://doi.org/10.1063/1.113266
Abstract: Nanoprecipitates in YBa2Cu3O7‐δ(YBCO) thin films have been identified by high resolution electron microscopy (HREM) as Y2O3 inclusions; they correspond to two different types of epitaxial relationships namely [001] or [110] parallel to the YBCOc‐axis. The [001] precipitates are situated near the YBCO surface, in the bulk and on the YBCO film/substrate interface. The [110] precipitates have only been observed at the surface. Literature data have been reinterpreted.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.302
Times cited: 28
DOI: 10.1063/1.113266
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“Synthesis of multi-branched porous carbon nanofibers and their application in electrochemical double-layer capacitors”. Tao XY, Zhang XB, Zhang L, Cheng JP, Liu F, Luo JH, Luo ZQ, Geise HJ, Carbon 44, 1425 (2006). http://doi.org/10.1016/j.carbon.2005.11.024
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 6.337
Times cited: 77
DOI: 10.1016/j.carbon.2005.11.024
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“Influence of the morphology on the magneto-transport properties of laser-ablated ultrathin La0.7Ba0.3MnO3 films”. Das A, Gordon I, Wagner P, Cannaerts M, Moshchalkov VV, Bruynseraede Y, Schuddinck W, Van Tendeloo G, Borghs G, Journal of applied physics 90, 1429 (2001). http://doi.org/10.1063/1.1380217
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 2.068
Times cited: 2
DOI: 10.1063/1.1380217
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“Reliable Characterization of Organic &, Pharmaceutical Compounds with High Resolution Monochromated EEL Spectroscopy”. Das PP, Guzzinati G, Coll C, Gomez Perez A, Nicolopoulos S, Estrade S, Peiro F, Verbeeck J, Zompra AA, Galanis AS, Polymers 12, 1434 (2020). http://doi.org/10.3390/polym12071434
Abstract: Organic and biological compounds (especially those related to the pharmaceutical industry) have always been of great interest for researchers due to their importance for the development of new drugs to diagnose, cure, treat or prevent disease. As many new API (active pharmaceutical ingredients) and their polymorphs are in nanocrystalline or in amorphous form blended with amorphous polymeric matrix (known as amorphous solid dispersion—ASD), their structural identification and characterization at nm scale with conventional X-Ray/Raman/IR techniques becomes difficult. During any API synthesis/production or in the formulated drug product, impurities must be identified and characterized. Electron energy loss spectroscopy (EELS) at high energy resolution by transmission electron microscope (TEM) is expected to be a promising technique to screen and identify the different (organic) compounds used in a typical pharmaceutical or biological system and to detect any impurities present, if any, during the synthesis or formulation process. In this work, we propose the use of monochromated TEM-EELS, to analyze selected peptides and organic compounds and their polymorphs. In order to validate EELS for fingerprinting (in low loss/optical region) and by further correlation with advanced DFT, simulations were utilized.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.364
Times cited: 6
DOI: 10.3390/polym12071434
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“Halide perovskite-lead chalcohalide nanocrystal heterostructures”. Imran M, Peng L, Pianetti A, Pinchetti V, Ramade J, Zito J, Di Stasio F, Buha J, Toso S, Song J, Infante I, Bals S, Brovelli S, Manna L, Journal Of The American Chemical Society 143, 1435 (2021). http://doi.org/10.1021/JACS.0C10916
Abstract: We report the synthesis of colloidal CsPbX3-Pb4S3Br2 (X = Cl, Br, I) nanocrystal heterostructures, providing an example of a sharp and atomically resolved epitaxial interface between a metal halide perovskite and a non-perovskite lattice. The CsPbBr3-Pb4S3Br2 nanocrystals are prepared by a two-step direct synthesis using preformed subnanometer CsPbBr3 clusters. Density functional theory calculations indicate the creation of a quasi-type II alignment at the heterointerface as well as the formation of localized trap states, promoting ultrafast separation of photogenerated excitons and carrier trapping, as confirmed by spectroscopic experiments. Postsynthesis reaction with either Cl- or I- ions delivers the corresponding CsPbCI3-Pb4S3Br2 and CsPbI3-Pb4S3Br2 heterostructures, thus enabling anion exchange only in the perovskite domain. An increased structural rigidity is conferred to the perovskite lattice when it is interfaced with the chalcohalide lattice. This is attested by the improved stability of the metastable gamma phase (or “black” phase) of CsPbI3 in the CsPbI3-Pb4S3Br2 heterostructure.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 13.858
Times cited: 54
DOI: 10.1021/JACS.0C10916
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“Multimodal zeolite-beta-based catalysts with a hierarchical, three-level pore structure”. Chen L-H, Li X-Y, Tian G, Li Y, Tan H-Y, Van Tendeloo G, Zhu G-S, Qiu S-L, Yang X-Y, Su B-L, Chemsuschem 4, 1452 (2011). http://doi.org/10.1002/cssc.201100181
Abstract: Hole diggers: The hierarchically structured porous solid-acid catalyst described in this report possess a remarkable pore system, encompassing well-defined macrochannels, interconnected mesopores, intracrystalline mesopores, and tunable zeolite micropores. Importantly, the catalyst exhibits very strong acidity and superior catalytic activity for esterification reactions.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 7.226
Times cited: 33
DOI: 10.1002/cssc.201100181
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“Heterogeneity of silica and glycan-epitope distribution in epidermal idioblast cell walls in Adiantum raddianum laminae”. Van Hoorebeke L, Leroux O, Leroux F, Mastroberti AA, Santos-Silva F, Van Loo D, Bagniewska-Zadworna A, Bals S, Popper ZA, de Araujo Mariath JE, Planta 237, 1453 (2013). http://doi.org/10.1007/s00425-013-1856-6
Abstract: Laminae of Adiantum raddianum Presl., a fern belonging to the family Pteridaceae, are characterised by the presence of epidermal fibre-like cells under the vascular bundles. These cells were thought to contain silica bodies, but their thickened walls leave no space for intracellular silica suggesting it may actually be deposited within their walls. Using advanced electron microscopy in conjunction with energy dispersive X-ray microanalysis we showed the presence of silica in the cell walls of the fibre-like idioblasts. However, it was specifically localised to the outer layers of the periclinal wall facing the leaf surface, with the thick secondary wall being devoid of silica. Immunocytochemical experiments were performed to ascertain the respective localisation of silica deposition and glycan polymers. Epitopes characteristic for pectic homogalacturonan and the hemicelluloses xyloglucan and mannan were detected in most epidermal walls, including the silica-rich cell wall layers. The monoclonal antibody, LM6, raised against pectic arabinan, labelled the silica-rich primary wall of the epidermal fibre-like cells and the guard cell walls, which were also shown to contain silica. We hypothesise that the silicified outer wall layers of the epidermal fibre-like cells support the lamina during cell expansion prior to secondary wall formation. This implies that silicification does not impede cell elongation. Although our results suggest that pectic arabinan may be implicated in silica deposition, further detailed analyses are needed to confirm this. The combinatorial approach presented here, which allows correlative screening and in situ localisation of silicon and cell wall polysaccharide distribution, shows great potential for future studies.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.361
Times cited: 16
DOI: 10.1007/s00425-013-1856-6
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“Structural and magnetotransport transitions in the electron-doped Pr1-xSrxMnO3(0.85\leq x\leq1) manganites”. Hervieu M, Martin C, Maignan A, Van Tendeloo G, Jirak Z, Hejtmanek J, Barnabe A, Thopart D, Raveau B, Chemistry and materials 12, 1456 (2000). http://doi.org/10.1021/cm000016o
Abstract: The exploration of the Mn4+-rich side of the Pr1-xSrxMnO3 system has allowed the extension of the domain of the cubic perovskite, by using a two-step process, combining synthesis under Ar flow at high temperature and O-2 pressure annealing at lower temperature. We show that these Pr-doped cubic perovskites exhibit a coupled structural (cubic-tetragonal) and magnetic (para-antiferro) transition connected with a resistivity jump at the same temperature. The strong interplay between lattice, charges, and spins for these oxides results from the appearance at low temperature of the distorted C-type antiferromagnetic structure. The Pr1-xSrxMnO3 magnetic phase diagram shows, for 0.9 less than or equal to x less than or equal to 1 (i.e., on the Mn4+-rich side), the existence at low temperature of C- and G-type antiferromagnetism. The absence of ferromagnetic-antiferromagnetic competition explains that magnetoresistante properties are not observed in this system, in contrast to Mn4+-rich Ln(1-x)Ca(x)MnO(3) systems.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 9.466
Times cited: 24
DOI: 10.1021/cm000016o
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