|
“Tuning Size and Seed Position in Small Silver Nanorods”. Sánchez-Iglesias A, Zhuo X, Albrecht W, Bals S, Liz-Marzán LM, ACS materials letters 2, 1246 (2020). http://doi.org/10.1021/acsmaterialslett.0c00388
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Times cited: 9
DOI: 10.1021/acsmaterialslett.0c00388
|
|
“In situ study of the formation mechanism of two-dimensional superlattices from PbSe nanocrystals”. Geuchies JJ, van Overbeek C, Evers WH, Goris B, de Backer A, Gantapara AP, Rabouw FT, Hilhorst J, Peters JL, Konovalov O, Petukhov AV, Dijkstra M, Siebbeles LDA, van Aert S, Bals S, Vanmaekelbergh D, Nature materials 15, 1248 (2016). http://doi.org/10.1038/nmat4746
Abstract: Oriented attachment of PbSe nanocubes can result in the formation of two-dimensional (2D) superstructures with long-range nanoscale and atomic order. This questions the applicability of classic models in which the superlattice grows by first forming a nucleus, followed by sequential irreversible attachment of nanocrystals, as one misaligned attachment would disrupt the 2D order beyond repair. Here, we demonstrate the formation mechanism of 2D PbSe superstructures with square geometry by using in situ grazing-incidence X-ray scattering (small angle and wide angle), ex situ electron microscopy, and Monte Carlo simulations. We observed nanocrystal adsorption at the liquid/gas interface, followed by the formation of a hexagonal nanocrystal monolayer. The hexagonal geometry transforms gradually through a pseudo-hexagonal phase into a phase with square order, driven by attractive interactions between the {100} planes perpendicular to the liquid substrate, which maximize facet-to-facet overlap. The nanocrystals then attach atomically via a necking process, resulting in 2D square superlattices.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 39.737
Times cited: 182
DOI: 10.1038/nmat4746
|
|
“Achieving Fast Kinetics and Enhanced Li Storage Capacity for Ti3C2O2 by Intercalation of Quinone Molecules”. Siriwardane EMD, Demiroglu I, Sevik C, Cakir D, ACS applied energy materials 2, 1251 (2019). http://doi.org/10.1021/ACSAEM.8B01801
Abstract: Using first-principles calculations, we demonstrated that high lithium storage capacity and fast kinetics are achieved for Ti3C2O2 by preintercalating organic molecules. As a proof-of-concept, two different quinone molecules, namely 1,4-benzoquinone (C6H4O2) and tetrafluoro-1,4-benzoquinone (C6F4O2) were selected as the molecular linkers to demonstrate the feasibility of this interlayer engineering strategy for energy storage. As compared to Ti3C2O2 bilayer without linker molecules, our pillared structures facilitate a much faster ion transport, promising a higher charge/discharge rate for Li. For example, while the diffusion barrier of a single Li ion within pristine Ti3C2O2 bilayer is at least 1.0 eV, it becomes 0.3 eV in pillared structures, which is comparable and even lower than that of commercial materials. At high Li concentrations, the calculated diffusion barriers are as low as 0.4 eV. Out-of-plane migration of Li ions is hindered due to large barrier energy with a value of around 1-1.35 eV. Concerning storage capacity, we can only intercalate one monolayer of Li within pristine Ti3C2O2 bilayer. In contrast, pillared structures offer significantly higher storage capacity. Our calculations showed that at least two layers of Li can be intercalated between Ti3C2O2 layers without forming bulk Li and losing the pillared structure upon Li loading/unloading. A small change in the in-plane lattice parameters (<0.5%) and volume (<1.0%) and ab initio molecular dynamics simulations prove the stability of the pillared structures against Li intercalation and thermal effects. Intercalated molecules avoid the large contraction/expansion of the whole structure, which is one of the key problems in electrochemical energy storage. Pillared structures allow us to realize electrodes with high capacity and fast kinetics. Our results open new research paths for improving the performance of not only MXenes but also other layered materials for supercapacitor and battery applications.
Keywords: A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
DOI: 10.1021/ACSAEM.8B01801
|
|
“Study on the giant positive magnetoresistance and Hall effect in ultrathin graphite flakes”. Vansweevelt R, Mortet V, D' Haen J, Ruttens bart, van Haesendonck C, Partoens B, Peeters FM, Wagner P, Physica status solidi : A : applications and materials science 208, 1252 (2011). http://doi.org/10.1002/pssa.201001206
Abstract: In this paper, we report on the electronic transport properties of mesoscopic, ultrathin graphite flakes with a thickness corresponding to a stack of 150 graphene layers. The graphite flakes show an unexpectedly strong positive magnetoresistance (PMR) already at room temperature, which scales in good approximation with the square of the magnetic field. Furthermore, we show that the resistivity is unaffected by magnetic fields oriented in plane with the graphene layers. Hall effect measurements indicate that the charge carriers are p-type and their concentration increases with increasing temperature while the mobility is decreasing. The Hall voltage is non-linear in higher magnetic fields. Possible origins of the observed effects are discussed. Ball and stick model of the two topmost carbon layers of the hexagonal graphite structure.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 1.775
Times cited: 8
DOI: 10.1002/pssa.201001206
|
|
“Photo-responsive metal-organic frameworks –, design strategies and emerging applications in photocatalysis and adsorption”. Scandura G, Eid S, Alnajjar AA, Paul T, Karanikolos GN, Shetty D, Omer K, Alqerem R, Juma A, Wang H, Arafat HA, Dumee LF, Materials Advances 4, 1258 (2023). http://doi.org/10.1039/D2MA01022D
Abstract: Stimuli-responsive metal-organic frameworks (MOFs) are highly versatile porous materials with the ability to respond to different external stimuli, including temperature, pressure, pH, and light. The MOF properties can switch reversibly under specific light irradiation, opening the doors to various applications. This review focuses on design strategies to obtain photo-responsive MOFs, namely (i) encapsulation of photo-switchable molecules as guests in MOF porous structures, (ii) fabrication of MOF composites, (iii) post-synthesis modification, and (iv) synthesis of MOFs with photo-responsive ligands. The most recent reports from the literature are herein reviewed and analyzed in terms of material chemistry and performance. Comparisons between the different strategies are performed and future challenges are discussed. The critical aspect of the fatigue of photo-responsive MOFs applied for prolonged cycling of irradiation is also discussed.
Keywords: A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
DOI: 10.1039/D2MA01022D
|
|
“Reply to Comment on “Frustrated octahedral tilting distortion in the incommensurately modulated Li3xNd2/3-xTiO3 perovskites””. Abakumov AM, Erni R, Tsirlin AA, Chemistry of materials 26, 1288 (2014). http://doi.org/10.1021/cm500005d
Keywords: Editorial; Electron microscopy for materials research (EMAT)
Impact Factor: 9.466
Times cited: 1
DOI: 10.1021/cm500005d
|
|
“Multilayer MoS2 growth by metal and metal oxide sulfurization”. Heyne MH, Chiappe D, Meersschaut J, Nuytten T, Conard T, Bender H, Huyghebaert C, Radu IP, Caymax M, de Marneffe JF, Neyts EC, De Gendt S;, Journal of materials chemistry C : materials for optical and electronic devices 4, 1295 (2016). http://doi.org/10.1039/c5tc04063a
Abstract: We investigated the deposition of MoS2 multilayers on large area substrates. The pre-deposition of metal or metal oxide with subsequent sulfurization is a promising technique to achieve layered films. We distinguish a different reaction behavior in metal oxide and metallic films and investigate the effect of the temperature, the H2S/H-2 gas mixture composition, and the role of the underlying substrate on the material quality. The results of the experiments suggest a MoS2 growth mechanism consisting of two subsequent process steps. At first, the reaction of the sulfur precursor with the metal or metal oxide occurs, requiring higher temperatures in the case of metallic film compared to metal oxide. At this stage, the basal planes assemble towards the diffusion direction of the reaction educts and products. After the sulfurization reaction, the material recrystallizes and the basal planes rearrange parallel to the substrate to minimize the surface energy. Therefore, substrates with low roughness show basal plane assembly parallel to the substrate. These results indicate that the substrate character has a significant impact on the assembly of low dimensional MoS2 films.
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 5.256
DOI: 10.1039/c5tc04063a
|
|
“Recent Advances in Transmission Electron Microscopy for Materials Science at the EMAT Lab of the University of Antwerp”. Guzzinati G, Altantzis T, Batuk M, De Backer A, Lumbeeck G, Samaee V, Batuk D, Idrissi H, Hadermann J, Van Aert S, Schryvers D, Verbeeck J, Bals S, Materials 11, 1304 (2018). http://doi.org/10.3390/ma11081304
Abstract: The rapid progress in materials science that enables the design of materials down to the nanoscale also demands characterization techniques able to analyze the materials down to the same scale, such as transmission electron microscopy. As Belgium’s foremost electron microscopy group, among the largest in the world, EMAT is continuously contributing to the development of TEM techniques, such as high-resolution imaging, diffraction, electron tomography, and spectroscopies, with an emphasis on quantification and reproducibility, as well as employing TEM methodology at the highest level to solve real-world materials science problems. The lab’s recent contributions are presented here together with specific case studies in order to highlight the usefulness of TEM to the advancement of materials science.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 2.654
Times cited: 15
DOI: 10.3390/ma11081304
|
|
“Pd@MOF-5: limitations of gas-phase infiltration and solution impregnation of [Zn4O(bdc)3] (MOF-5) with metalorganic palladium precursors for loading with Pd nanoparticles”. Esken D, Zhang X, Lebedev OI, Schröder F, Fischer RA, Journal of materials chemistry 19, 1314 (2009). http://doi.org/10.1039/b815977g
Abstract: The limitations of the loading of the porous metalorganic framework [Zn4O(bdc)3] (bdc = benzene-1,4-dicarboxylate; MOF-5 or IRMOF-1) with Pd nanoparticles was investigated. First, the volatile organometallic precursor [Pd(5-C5H5)(3-C3H5)] was employed to get the inclusion compound [Pd(5-C5H5)(3-C3H5)]x@MOF-5 via gas-phase infiltration at 10-3 mbar. A loading of four molecules of [Pd(5-C5H5)(3-C3H5)] per formula unit of MOF-5 (x = 4) can be reached (35 wt.% Pd). Second, the metalorganic precursor [Pd(acac)2] (acac = 2,4-pentanedionate) was used and the inclusion materials [Pd(acac)2]x@MOF-5 of different Pd loadings were obtained by incipient wetness infiltration. However, the maximum loading was lower as compared with the former case with about two precursor molecules per formula unit of MOF-5. Both loading routes are suitable for the synthesis of Pd nanoparticles inside the porous host matrix. Homogeneously distributed nanoparticles with diameter of 2.4(±0.2) nm can be achieved by photolysis of the inclusion compounds [Pd(5-C5H5)(3-C3H5)]x@MOF-5 (x 4), while the hydrogenolysis of [Pd(acac)2]x@MOF-5 (x 2) leads to a mixture of small particles inside the network (< 3 nm) and large Pd agglomerates (40 nm) on the outer surface of the MOF-5 specimens. The pure Pdx@MOF-5 materials proved to be stable under hydrogen pressure (2 bar) at 150 °C over many hours. Neither hydrogenation of the bdc linkers nor particle growth was observed. The new composite materials were characterized by 1H/13C-MAS-NMR, powder XRD, ICP-AES, FT-IR, N2 sorption measurements and high resolution TEM. Raising the Pd loading of a representative sample Pd4@MOF-5 (35 wt.% Pd) by using [Pd(5-C5H5)(3-C3H5)] as precursor in a second cycle of gas-phase infiltration and photolysis was accompanied by the collapse of the long-range crystalline order of the MOF.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Times cited: 100
DOI: 10.1039/b815977g
|
|
“Structure determination of spherical MCM-41 particles”. Pauwels B, Van Tendeloo G, Thoelen C, van Rhijn W, Jacobs PA, Advanced materials 13, 1317 (2001). http://doi.org/10.1002/1521-4095(200109)13:17<1317::AID-ADMA1317>3.0.CO;2-5
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 19.791
Times cited: 91
DOI: 10.1002/1521-4095(200109)13:17<1317::AID-ADMA1317>3.0.CO;2-5
|
|
“Misfit accommodation of epitaxial La1-xAxMnO3 (A=Ca, Sr) thin films”. Lebedev OI, Van Tendeloo G, Amelinckx S, International journal of inorganic materials 3, 1331 (2001). http://doi.org/10.1016/S1466-6049(01)00155-6
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Times cited: 2
DOI: 10.1016/S1466-6049(01)00155-6
|
|
“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
|
|
“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
|
|
“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
|
|
“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
|
|
“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
|
|
“Functionalization of single-layer TaS₂, and formation of ultrathin Janus structures”. Kahraman Z, Yagmurcukardes M, Sahin H, Journal Of Materials Research 35, 1397 (2020). http://doi.org/10.1557/JMR.2020.64
Abstract: Ab initio calculations are performed to investigate the structural, vibrational, electronic, and piezoelectric properties of functionalized single layers of TaS2. We find that single-layer TaS2 is a suitable host material for functionalization via fluorination and hydrogenation. The one-side fluorinated (FTaS2) and hydrogenated (HTaS2) single layers display indirect gap semiconducting behavior in contrast to bare metallic TaS2. On the other hand, it is shown that as both surfaces of TaS2 are saturated anti-symmetrically, the formed Janus structure is a dynamically stable metallic single layer. In addition, it is revealed that out-of-plane piezoelectricity is created in all anti-symmetric structures. Furthermore, the Janus-type single-layer has the highest specific heat capacity to which longitudinal and transverse acoustical phonon modes have contribution at low temperatures. Our findings indicate that single-layer TaS2 is suitable for functionalization via H and F atoms that the formed, anti-symmetric structures display distinctive electronic, vibrational, and piezoelectric properties.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.7
Times cited: 1
DOI: 10.1557/JMR.2020.64
|
|
“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
|
|
“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
|
|
“Quantum transport of a two-dimensional electron gas in a spatially modulated magnetic field”. Peeters FM, Vasilopoulos P, Physical review : B : condensed matter and materials physics 47, 1466 (1993). http://doi.org/10.1103/PhysRevB.47.1466
Abstract: Electrical transport properties of a two-dimensional electron gas axe studied in the presence of a perpendicular magnetic field B modulated weakly and periodically along one direction, B = (B + B0 cos Kx)z, with B0 much less than B, K = 2pi/a, and a being the period of the modulation. B0 is taken constant or proportional to B. The Landau levels broaden into bands and their width, proportional to the modulation strength B0, oscillates with B and gives rise to oscillations in the magnetoresistance at low B. These oscillations reflect the commensurability between the cyclotron diameter at the Fermi level and the period a and consequently hey are distinctly different from the Shubnikov-de Ha.as ones, at higher B, in period and temperature dependence. The bandwidth at the Fermi energy can be one order of magnitude larger, at low B, than that of the electric case for equal modulation strengths. The resulting magnetoresistance oscillations have a much higher amplitude than those of the electric case with which they are out of phase. Explicit asymptotic expressions are derived for the temperature dependence of the transport coefficients. The case when both electric and magnetic modulations are present is also considered. The position of the resulting oscillations depends on the ratio delta between the two modulation strengths. When the modulations are out of phase there is no shift in the position of the oscillations when delta varies and for a particular value of delta the oscillations are suppressed.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.736
Times cited: 169
DOI: 10.1103/PhysRevB.47.1466
|
|
“Magneto-polaron effect on shallow indium donors in CdTe”. Grynberg M, Huant S, Martinez G, Kossut J, Wojtowicz T, Karczewski G, Shi JM, Peeters FM, Devreese JT, Physical review : B : condensed matter and materials physics 54, 1467 (1996). http://doi.org/10.1103/PhysRevB.54.1467
Keywords: A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems
Impact Factor: 3.736
Times cited: 33
DOI: 10.1103/PhysRevB.54.1467
|
|
“Two electron quantum disks”. Peeters FM, Schweigert VA, Physical review : B : condensed matter and materials physics 53, 1468 (1996). http://doi.org/10.1103/PhysRevB.53.1468
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.736
Times cited: 204
DOI: 10.1103/PhysRevB.53.1468
|
|
“Understanding superionic conductivity in lithium and sodium salts of weakly coordinating closo-hexahalocarbaborate anions”. Jorgensen M, Shea PT, Tomich AW, Varley JB, Bercx M, Lovera S, Cerny R, Zhou W, Udovic TJ, Lavallo V, Jensen TR, Wood BC, Stavila V, Chemistry of materials 32, 1475 (2020). http://doi.org/10.1021/ACS.CHEMMATER.9B04383
Abstract: Solid-state ion conductors based on closo-polyborate anions combine high ionic conductivity with a rich array of tunable properties. Cation mobility in these systems is intimately related to the strength of the interaction with the neighboring anionic network and the energy for reorganizing the coordination polyhedra. Here, we explore such factors in solid electrolytes with two anions of the weakest coordinating ability, [HCB11H5Cl6](-) and [HCB11H5Br6](-), and a total of 11 polymorphs are identified for their lithium and sodium salts. Our approach combines ab initio molecular dynamics, synchrotron X-ray powder diffraction, differential scanning calorimetry, and AC impedance measurements to investigate their structures, phase-transition behavior, anion orientational mobilities, and ionic conductivities. We find that M(HCB11H5X6) (M = Li, Na, X = Cl, Br) compounds exhibit order-disorder polymorphic transitions between 203 and 305 degrees C and display Li and Na superionic conductivity in the disordered state. Through detailed analysis, we illustrate how cation disordering in these compounds originates from a competitive interplay among the lattice symmetry, the anion reorientational mobility, the geometric and electronic asymmetry of the anion, and the polarizability of the halogen atoms. These factors are compared to other closo-polyborate-based ion conductors to suggest guidelines for optimizing the cation-anion interaction for fast ion mobility. This study expands the known solid-state poly(carba)borate-based materials capable of liquid-like ionic conductivities, unravels the mechanisms responsible for fast ion transport, and provides insights into the development of practical superionic solid electrolytes.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Times cited: 5
DOI: 10.1021/ACS.CHEMMATER.9B04383
|
|
“Structures and magnetism of La1-xSrxMnO3-(0.5+x)/2 (0.67\leq x\leq1) phases”. Dixon E, Hadermann J, Hayward MA, Chemistry of materials 24, 1486 (2012). http://doi.org/10.1021/cm300199b
Abstract: Topotactic reduction of La1-xSrxMnO3 (0.67 <= x <= 1) phases with sodium hydride yields a series of isoelectronic materials of composition La1-xSrxMnO3-(0.5+x)/2. Lanthanum rich members of the series (0.67 <= x <= 0.83) adopt anion deficient perovskite structures with a 6-layer -OTOOT'O- stacking sequence of sheets of octahedra/square-based pyramids (O) and sheets of tetrahedra (T). The strontium rich members of the series (0.83 <= x <= 1) incorporate “step defects” into this 6-layer structure in which the OTOOT'O stacking sequence is converted into either OOTOOT' or TOOT'OO at a defect plane which runs perpendicular to the [201] lattice plane. The step defects appear to provide a mechanism to relieve lattice strain and accommodate additional anion deficiency in phases with x > 0.83. Magnetization and neutron diffraction data indicate La1-xSrxMnO3-(0.5+x)/2 phases adopt antiferromagnetically ordered states at low-temperature in which the ordered arrangement of magnetic spins is incommensurate with the crystallographic lattice.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 9.466
Times cited: 13
DOI: 10.1021/cm300199b
|
|
“Two-Dimensional CdSe-PbSe Heterostructures and PbSe Nanoplatelets: Formation, Atomic Structure, and Optical Properties”. Salzmann BBV, Wit J de, Li C, Arenas-Esteban D, Bals S, Meijerink A, Vanmaekelbergh D, The journal of physical chemistry: C : nanomaterials and interfaces 126, 1513 (2022). http://doi.org/10.1021/acs.jpcc.1c09412
Keywords: A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Impact Factor: 3.7
Times cited: 12
DOI: 10.1021/acs.jpcc.1c09412
|
|
“Influence of laser and isothermal treatments on microstructural properties of SnO2 films”. Rembeza ES, Richard O, van Landuyt J, Materials research bulletin 34, 1527 (1999). http://doi.org/10.1016/S0025-5408(99)00188-9
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 2.446
Times cited: 17
DOI: 10.1016/S0025-5408(99)00188-9
|
|
“Chemical composition of building materials used in Turkey”. Čevik U, Damla N, Van Grieken R, Vefa Akpinar M, Construction and building materials 25, 1546 (2011). http://doi.org/10.1016/J.CONBUILDMAT.2010.08.011
Abstract: The main goal of this work was to determine the chemical composition of building materials used in Turkey by utilizing energy dispersive X-ray fluorescence (EDXRF) spectrometry. Gas concrete, cement, sand, bricks, roofing tiles, marble, lime and gypsum materials were selected as building materials for this research. The chemical contents and their trace concentrations of the selected samples were determined. The most abundant oxides measured were generally SiO2, Al2O3, CaO, MgO, Fe2O3, K2O and SO3 for all samples. While the main chemical component of gas concrete, cement, sand and marble samples were SiO2 and CaO, brick and roofing tile mainly consisted of SiO2 and Al2O3. CaO and SO3 were major component of lime and gypsum samples, respectively. For U and Th concentrations in the samples, activities of 226Ra and 232Th were measured by utilizing gamma spectrometry. ANOVA and Pearson correlation analyses were performed on the studied data for statistical analysis.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1016/J.CONBUILDMAT.2010.08.011
|
|
“Role of the carbon support on the oxygen reduction and evolution activities in LaNiO3 composite electrodes in alkaline solution”. Alexander CT, Abakumov AM, Forslund RP, Johnston KP, Stevenson KJ, ACS applied energy materials 1, 1549 (2018). http://doi.org/10.1021/ACSAEM.7B00339
Abstract: Metal-air batteries and fuel cells show a great deal of promise in advancing low-cost, high-energy-density charge storage solutions for sustainable energy applications. To improve the activities and stabilities of electrocatalysts for the critical oxygen reduction and evolution reactions (ORR and OER, respectively), a greater understanding is needed of the catalyst/carbon interactions and carbon stability. Herein, we report how LaNiO3 (LNO) supported on nitrogen-doped carbon nanotubes (N-CNT) made from a high-yield synthesis lowers the overpotential for both the OER and ORR markedly to enable a low bifunctional window of 0.81 V at only a 51 mu g cm(-2) mass loading. Furthermore, the addition of LNO to the N-CNTs improves the galvanostatic stability for the OER by almost 2 orders of magnitude. The nanoscale geometries of the perovskites and the CNTs enhance the number of metal-support and charge transfer interactions and thus the activity. We use rotating ring disk electrodes (RRDEs) combined with Tafel slope analysis and ICP-OES to quantitatively separate current contributions from the OER, carbon oxidation, and even anodic iron leaching from carbon nanotubes.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
DOI: 10.1021/ACSAEM.7B00339
|
|
“Electrophonon resonances in a quasi-two-dimensional electron system”. Xu W, Peeters FM, Devreese JT, Physical review : B : condensed matter and materials physics 48, 1562 (1993). http://doi.org/10.1103/PhysRevB.48.1562
Abstract: When the energy difference between two electric subbands in a quasi-two-dimensional electron system equals a LO-phonon energy, resonant scattering will occur. This leads to an enhancement of the scattering rate and, consequently, to a suppression of the conductivity. Changing the energy difference between the electric subbands (e.g., through a gate) leads to a series of electrophonon resonances in the conductivity. A detailed study is made of this effect for different confinement potentials. We found that the scattering processes where the emission of a phonon is involved are very important for the electrophonon resonance and that the size of the effect decreases with increasing temperature.
Keywords: A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems
Impact Factor: 3.736
Times cited: 45
DOI: 10.1103/PhysRevB.48.1562
|
|
“New lead vanadium phosphate with langbeinite-type structure: Pb1.5V2(PO4)3”. Shpanchenko RV, Lapshina OA, Antipov EV, Hadermann J, Kaul EE, Geibel C, Materials research bulletin 40, 1569 (2005). http://doi.org/10.1016/j.materresbull.2005.04.037
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 2.446
Times cited: 14
DOI: 10.1016/j.materresbull.2005.04.037
|