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| Author | Vandemeulebroucke, D.; Batuk, M.; Hajizadeh, A.; Wastiaux, M.; Roussel, P.; Hadermann, J. | ||||
| Title | Incommensurate Modulations and Perovskite Growth in LaxSr2–xMnO4−δAffecting Solid Oxide Fuel Cell Conductivity | Type | A1 Journal Article | ||
| Year | 2024 | Publication | Chemistry of Materials | Abbreviated Journal | Chem. Mater. |
| Volume | Issue | Pages | |||
| Keywords | A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; | ||||
| Abstract | Ruddlesden-Popper La????Sr2−????MnO4−???? materials are interesting symmetric solid oxide fuel cell electrodes due to their good redox stability, mixed ionic and electronic conducting behavior and thermal expansion that matches well with common electrolytes. In reducing environments – as at a solid oxide fuel cell anode – the x = 0.5 member, i.e. La0.5Sr1.5MnO4−????, has a much higher total conductivity than compounds with a different La/Sr ratio, although all those compositions have the same K2NiF4-type I4/mmm structure. The origin for this conductivity difference is not yet known in literature. Now, a combination of in-situ and ex-situ 3D electron diffraction, high-resolution imaging, energy-dispersive X-ray analysis and electron energy-loss spectroscopy uncovered clear differences between x=0.25 and x=0.5 in the pristine structure, as well as in the transformations upon high-temperature reduction. In La0.5Sr1.5MnO4−????, Ruddlesden-Popper n=2 layer defects and an amorphous surface layer are present, but not in La0.25Sr1.75MnO4−????. After annealing at 700°C in 5% H2/Ar, La0.25Sr1.75MnO4−???? transforms to a tetragonal 2D incommensurately modulated structure with modulation vectors ⃗????1 = 0.2848(1) · (⃗????* +⃗????*) and ⃗????2 =0.2848(1) · (⃗????* – ⃗????*), whereas La0.5Sr1.5MnO4−???? only partially transforms to an orthorhombic 1D incommensurately modulated structure, with ⃗???? = 0.318(2) · ⃗????*. Perovskite domains grow at the crystal edge at 700°C in 5% H2 or vacuum, due to the higher La concentration on the surface compared to the bulk, which leads to a different thermodynamic equilibrium. Since it is known that a lower degree of oxygen vacancy ordering and a higher amount of perovskite blocks enhance oxygen mobility, those differences in defect structure and structural transformation upon reduction, might all contribute to the higher conductivity of La0.5Sr1.5MnO4−???? in solid oxide fuel cell anode conditions compared to other La/Sr ratios. |
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| Language | English | Wos | 001174840900001 | Publication Date | 2024-02-20 |
| Series Editor | Series Title | Abbreviated Series Title | |||
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Edition | |||
| ISSN | 0897-4756 | ISBN | Additional Links | UA library record; WoS full record | |
| Impact Factor | 8.6 | Times cited | Open Access | Not_Open_Access | |
| Notes | Universiteit Antwerpen, BOF TOP 38689 ; Fonds Wetenschappelijk Onderzoek, I003218N ; European Commission NanED, 956099 ; | Approved | Most recent IF: 8.6; 2024 IF: 9.466 | ||
| Call Number | EMAT @ emat @c:irua:204354 | Serial | 8997 | ||
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| Author | Chakraborty, J.; Chatterjee, A.; Molkens, K.; Nath, I.; Arenas Esteban, D.; Bourda, L.; Watson, G.; Liu, C.; Van Thourhout, D.; Bals, S.; Geiregat, P.; Van der Voort, P. | ||||
| Title | Decoding Excimer Formation in Covalent–Organic Frameworks Induced by Morphology and Ring Torsion | Type | A1 Journal Article | ||
| Year | 2024 | Publication | Advanced Materials | Abbreviated Journal | Advanced Materials |
| Volume | Issue | Pages | |||
| Keywords | A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; | ||||
| Abstract | A thorough and quantitative understanding of the fate of excitons in covalent–organic frameworks (COFs) after photoexcitation is essential for their augmented optoelectronic and photocatalytic applications via precise structure tuning. The synthesis of a library of COFs having identical chemical backbone with impeded conjugation, but varied morphology and surface topography to study the effect of these physical properties on the photophysics of the materials is herein reported. The variation of crystallite size and surface topography substantified different aggregation pattern in the COFs, which leads to disparities in their photoexcitation and relaxation properties. Depending on aggregation, an inverse correlation between bulk luminescence decay time and exciton binding energy of the materials is perceived. Further transient absorption spectroscopic analysis confirms the presence of highly localized, immobile, Frenkel excitons (of diameter 0.3–0.5 nm) via an absence of annihilation at high density, most likely induced by structural torsion of the COF skeletons, which in turn preferentially relaxes via long‐lived (nanosecond to microsecond) excimer formation (in femtosecond scale) over direct emission. These insights underpin the importance of structural and topological design of COFs for their targeted use in photocatalysis. | ||||
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| Language | Wos | 001206226700001 | Publication Date | 2024-04-22 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
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Edition | |||
| ISSN | 0935-9648 | ISBN | Additional Links | UA library record; WoS full record | |
| Impact Factor | 29.4 | Times cited | Open Access | ||
| Notes | PVDV, JC, AC, and IN acknowledge the FWO-Vlaanderen for research grant G020521N and the research board of UGent (BOF) through a Concerted Research Action (GOA010-17). JC acknowledges UGent for BOF postdoctoral grant (2022.0032.01). AC acknowledges FWO- Vlaanderen for postdoctoral grant (12T7521N). KM, DVT and PG acknowledges FWO- Vlaanderen for research grant G0B2921N. SB and DAE acknowledge financial support from ERC Consolidator Grant Number 815128 REALNANO. CHL acknowledges China Scholarship Council doctoral grant (201908110280). PVDV acknowledges Hercules Project AUGE/17/07 for the UV VIS DRS spectrometer and UGent BASBOF BOF20/BAS/015 for the powder X-Ray Diffractometer. PG thanks UGent for support of the Core Facility NOLIMITS. | Approved | Most recent IF: 29.4; 2024 IF: 19.791 | ||
| Call Number | EMAT @ emat @c:irua:205967 | Serial | 9118 | ||
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| Author | Esteban, D.A.; Chamocho, E.G.; Carretero González, J.; Urones Garrote, E.; Otero Díaz, L.C.; Brande, D.Á. | ||||
| Title | Enhancing Electrochemical Properties of Walnut Shell Activated Carbon with Embedded MnO Clusters for Supercapacitor Applications | Type | A1 Journal Article | ||
| Year | 2024 | Publication | Batteries & Supercaps | Abbreviated Journal | Batteries & Supercaps |
| Volume | Issue | Pages | |||
| Keywords | A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; | ||||
| Abstract | Activated carbon (AC) materials from renewable sources are widely used in electrochemical applications due to their well‐known high surface area. However, their application as electrode material in double‐layer electrochemical devices may be limited due to their relatively low electrical conductivity and lightweight. To overcome these limitations, the incorporation of pseudocapacitance metal oxide nanoparticles is an optimum approach. These nanoparticles can provide a second energy storage mechanism to the composite, mitigating the loss of surface area associated with their incorporation. As a result, the composite material is endowed with increased conductivity and higher density, making it more suitable for practical implementation in real devices. In this study, we have incorporated a fine dispersion of 1 % of MnO clusters into a highly porous activated carbon synthesized from walnut shells (WAC). The high‐resolution electron microscopy studies, combined with their related analytical techniques, allow us to determine the presence of the cluster within the matrix carbon precisely. The resulting MnO@WAC composite demonstrated significantly improved capacitive behavior compared with the WAC material, with increased volumetric capacitance and higher charge retention at higher current densities. The composite‘s electrochemical performance suggests its potential as a promising electrode material for supercapacitors, addressing drawbacks associated with traditional AC materials. | ||||
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| Language | Wos | 001198179300001 | Publication Date | 2024-04-08 | |
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| ISSN | 2566-6223 | ISBN | Additional Links | UA library record; WoS full record | |
| Impact Factor | Times cited | Open Access | |||
| Notes | Grants PID2020-112848RB-C21 funded by MCIN/AEI/ 10.13039/501100011033 and by the European Union PRTR funding through projects are acknowledged. Access to the ICTS- CNME for TEM is also acknowledged. | Approved | Most recent IF: NA | ||
| Call Number | EMAT @ emat @c:irua:205463 | Serial | 9119 | ||
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| Author | Ignatova, K.; Vlasov, E.; Seddon, S.D.; Gauquelin, N.; Verbeeck, J.; Wermeille, D.; Bals, S.; Hase, T.P.A.; Arnalds, U.B. | ||||
| Title | Phase coexistence induced surface roughness in V2O3/Ni magnetic heterostructures | Type | A1 Journal Article | ||
| Year | 2024 | Publication | APL Materials | Abbreviated Journal | |
| Volume | 12 | Issue | 4 | Pages | |
| Keywords | A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; | ||||
| Abstract | We present an investigation of the microstructure changes in V2O3 as it goes through its inherent structural phase transition. Using V2O3 films with a well-defined crystal structure deposited by reactive magnetron sputtering on r-plane Al2O3 substrates, we study the phase coexistence region and its impact on the surface roughness of the films and the magnetic properties of overlying Ni magnetic layers in V2O3/Ni hybrid magnetic heterostructures. The simultaneous presence of two phases in V2O3 during its structural phase transition was identified with high resolution x-ray diffraction and led to an increase in surface roughness observed using x-ray reflectivity. The roughness reaches its maximum at the midpoint of the transition. In V2O3/Ni hybrid heterostructures, we find a concomitant increase in the coercivity of the magnetic layer correlated with the increased roughness of the V2O3 surface. The chemical homogeneity of the V2O3 is confirmed through transmission electron microscopy analysis. High-angle annular dark field imaging and electron energy loss spectroscopy reveal an atomically flat interface between Al2O3 and V2O3, as well as a sharp interface between V2O3 and Ni. | ||||
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| Language | Wos | 001202661800003 | Publication Date | 2024-04-01 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue |
Edition | |||
| ISSN | 2166-532X | ISBN | Additional Links | UA library record; WoS full record | |
| Impact Factor | 6.1 | Times cited | Open Access | ||
| Notes | This work was supported by the funding from the University of Iceland Research Fund, the Icelandic Research Fund Grant No. 207111. Instrumentation funding from the Icelandic Infrastructure Fund is acknowledged. This work was based on experiments per- formed at the BM28 (XMaS) beamline at the European Synchrotron Radiation Facility, Grenoble, France. XMaS is a National Research Facility funded by the UK EPSRC and managed by the Universi- ties of Liverpool and Warwick. This project has received funding from the European Union’s Horizon 2020 research and innovation program under Grant Agreement No. 823717—ESTEEM3. | Approved | Most recent IF: 6.1; 2024 IF: 4.335 | ||
| Call Number | EMAT @ emat @c:irua:205569 | Serial | 9120 | ||
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| Author | Vlasov, E.; Heyvaert, W.; Ni, B.; Van Gordon, K.; Girod, R.; Verbeeck, J.; Liz-Marzán, L.M.; Bals, S. | ||||
| Title | High-Throughput Morphological Chirality Quantification of Twisted and Wrinkled Gold Nanorods | Type | A1 Journal Article | ||
| Year | 2024 | Publication | ACS Nano | Abbreviated Journal | ACS Nano |
| Volume | Issue | Pages | |||
| Keywords | A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; | ||||
| Abstract | Chirality in gold nanostructures offers an exciting opportunity to tune their differential optical response to left- and right-handed circularly polarized light, as well as their interactions with biomolecules and living matter. However, tuning and understanding such interactions demands quantification of the structural features that are responsible for the chiral behavior. Electron tomography (ET) enables structural characterization at the single-particle level and has been used to quantify the helicity of complex chiral nanorods. However, the technique is time-consuming and consequently lacks statistical value. To address this issue, we introduce herein a high-throughput methodology that combines images acquired by secondary electron-based electron beam-induced current (SEEBIC) with quantitative image analysis. As a result, the geometric chirality of hundreds of nanoparticles can be quantified in less than 1 h. When combining the drastic gain in data collection efficiency of SEEBIC with a limited number of ET data sets, a better understanding of how the chiral structure of individual chiral nanoparticles translates into the ensemble chiroptical response can be reached. | ||||
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| Language | Wos | Publication Date | 2024-04-26 | ||
| Series Editor | Series Title | Abbreviated Series Title | |||
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Edition | |||
| ISSN | 1936-0851 | ISBN | Additional Links | ||
| Impact Factor | 17.1 | Times cited | Open Access | ||
| Notes | The authors acknowledge financial support by the European Research Council (ERC CoG No. 815128 REALNANO to S.B.) and from MCIN/AEI/10.13039/501100011033 (Grant PID2020-117779RB-I00 to L.M.L.-M and FPI Fellowship PRE2021-097588 to K.V.G.). Funded by the European Union under Project 101131111 − DELIGHT, JV acknowledges the eBEAM project supported by the European Union’s Horizon 2020 research and innovation program FETPROACT-EIC-07- 2020: emerging paradigms and communities. | Approved | Most recent IF: 17.1; 2024 IF: 13.942 | ||
| Call Number | EMAT @ emat @ | Serial | 9121 | ||
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| Author | Guerrero, R.M.; Lemir, I.D.; Carrasco, S.; Fernández-Ruiz, C.; Kavak, S.; Pizarro, P.; Serrano, D.P.; Bals, S.; Horcajada, P.; Pérez, Y. | ||||
| Title | Scaling-Up Microwave-Assisted Synthesis of Highly Defective Pd@UiO-66-NH2Catalysts for Selective Olefin Hydrogenation under Ambient Conditions | Type | A1 Journal Article | ||
| Year | 2024 | Publication | ACS Applied Materials & Interfaces | Abbreviated Journal | ACS Appl. Mater. Interfaces |
| Volume | Issue | Pages | |||
| Keywords | A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; | ||||
| Abstract | The need to develop green and cost-effective industrial catalytic processes has led to growing interest in preparing more robust, efficient, and selective heterogeneous catalysts at a large scale. In this regard, microwave-assisted synthesis is a fast method for fabricating heterogeneous catalysts (including metal oxides, zeolites, metal–organic frameworks, and supported metal nanoparticles) with enhanced catalytic properties, enabling synthesis scale-up. Herein, the synthesis of nanosized UiO-66-NH2 was optimized via a microwave-assisted hydrothermal method to obtain defective matrices essential for the stabilization of metal nanoparticles, promoting catalytically active sites for hydrogenation reactions (760 kg·m–3·day–1 space time yield, STY). Then, this protocol was scaled up in a multimodal microwave reactor, reaching 86% yield (ca. 1 g, 1450 kg·m–3·day–1 STY) in only 30 min. Afterward, Pd nanoparticles were formed in situ decorating the nanoMOF by an effective and fast microwave-assisted hydrothermal method, resulting in the formation of Pd@UiO-66-NH2 composites. Both the localization and oxidation states of Pd nanoparticles (NPs) in the MOF were achieved using high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) and X-ray photoelectron spectroscopy (XPS), respectively. The optimal composite, loaded with 1.7 wt % Pd, exhibited an extraordinary catalytic activity (>95% yield, 100% selectivity) under mild conditions (1 bar H2, 25 °C, 1 h reaction time), not only in the selective hydrogenation of a variety of single alkenes (1-hexene, 1-octene, 1-tridecene, cyclohexene, and tetraphenyl ethylene) but also in the conversion of a complex mixture of alkenes (i.e., 1-hexene, 1-tridecene, and anethole). The results showed a powerful interaction and synergy between the active phase (Pd NPs) and the catalytic porous scaffold (UiO-66-NH2), which are essential for the selectivity and recyclability. | ||||
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| Language | Wos | Publication Date | 2024-04-26 | ||
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Edition | |||
| ISSN | 1944-8244 | ISBN | Additional Links | ||
| Impact Factor | 9.5 | Times cited | Open Access | ||
| Notes | The authors gratefully acknowledge financial support from “Comunidad de Madrid” and European Regional Development Fund-FEDER through the project HUB MADRID+CIRCULAR; the State Research Agency (MCIN/AEI /10.13039/501100011033) through the grant with reference number CEX2019-000931-M received in the 2019 call for “Severo Ochoa Centres of Excellence” and “María de Maeztu Units of Excellence” of the State Programme for Knowledge Generation and Scientific and Technological Strengthening of the R&D&I System; and MICIU through the project “NAPOLION” (PID2022-139956OB-I00). S.K. acknowledges the Flemish Fund for Scientific Research (FWO Vlaanderen) through a PhD research grant (1181124N). | Approved | Most recent IF: 9.5; 2024 IF: 7.504 | ||
| Call Number | EMAT @ emat @ | Serial | 9126 | ||
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| Author | Leinders, G.; Grendal, O.G.; Arts, I.; Bes, R.; Prozheev, I.; Orlat, S.; Fitch, A.; Kvashnina, K.; Verwerft, M. | ||||
| Title | Refinement of the uranium dispersion corrections from anomalous diffraction | Type | A1 Journal Article | ||
| Year | 2024 | Publication | Journal of Applied Crystallography | Abbreviated Journal | J Appl Cryst |
| Volume | 57 | Issue | 2 | Pages | 284-295 |
| Keywords | A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; | ||||
| Abstract | The evolution of the uranium chemical state in uranium compounds, principally in the oxides, is of concern in the context of nuclear fuel degradation under storage and repository conditions, and in accident scenarios. The U–O system shows complicated phase relations between single-valence uranium dioxide (UO<sub>2</sub>) and different mixed-valence compounds (<italic>e.g.</italic>U<sub>4</sub>O<sub>9</sub>, U<sub>3</sub>O<sub>7</sub>and U<sub>3</sub>O<sub>8</sub>). To try resolving the electronic structure associated with unique atomic positions, a combined application of diffraction and spectroscopic techniques, such as diffraction anomalous fine structure (DAFS), can be considered. Reported here is the application of two newly developed routines for assessing a DAFS data set, with the aim of refining the uranium X-ray dispersion corrections. High-resolution anomalous diffraction data were acquired from polycrystalline powder samples of UO<sub>2</sub>(containing tetravalent uranium) and potassium uranate (KUO<sub>3</sub>, containing pentavalent uranium) using synchrotron radiation in the vicinity of the U<italic>L</italic><sub>3</sub>edge (17.17 keV). Both routines are based on an iterative refinement of the dispersion corrections, but they differ in either using the intensity of a selection of reflections or doing a full-pattern (Rietveld method) refinement. The uranium dispersion corrections obtained using either method are in excellent agreement with each other, and they show in great detail the chemical shifts and differences in fine structure expected for tetravalent and pentavalent uranium. This approach may open new possibilities for the assessment of other, more complicated, materials such as mixed-valence compounds. Additionally, the DAFS methodology can offer a significant resource optimization because each data set contains both structural (diffraction) and chemical (spectroscopy) information, which can avoid the requirement to use multiple experimental stations at synchrotron sources. | ||||
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| Language | Wos | 001208800100008 | Publication Date | 2024-04-01 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue |
Edition | |||
| ISSN | 1600-5767 | ISBN | Additional Links | UA library record; WoS full record | |
| Impact Factor | 6.1 | Times cited | Open Access | ||
| Notes | FPS Economy, SF-CORMOD; | Approved | Most recent IF: 6.1; 2024 IF: 2.495 | ||
| Call Number | EMAT @ emat @c:irua:206011 | Serial | 9127 | ||
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| Author | Van Gordon, K.; Ni, B.; Girod, R.; Mychinko, M.; Bevilacqua, F.; Bals, S.; Liz‐Marzán, L.M. | ||||
| Title | Single Crystal and Pentatwinned Gold Nanorods Result in Chiral Nanocrystals with Reverse Handedness | Type | A1 Journal Article | ||
| Year | 2024 | Publication | Angewandte Chemie International Edition | Abbreviated Journal | Angew Chem Int Ed |
| Volume | Issue | Pages | |||
| Keywords | A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; | ||||
| Abstract | Handedness is an essential attribute of chiral nanocrystals, having a major influence on their properties. During chemical growth, the handedness of nanocrystals is usually tuned by selecting the corresponding enantiomer of chiral molecules involved in asymmetric growth, often known as chiral inducers. We report that, even using the same chiral inducer enantiomer, the handedness of chiral gold nanocrystals can be reversed by using Au nanorod seeds with either single crystalline or pentatwinned structure. This effect holds for chiral growth induced both by amino acids and by chiral micelles. Although it was challenging to discern the morphological handedness for<italic>L</italic>‐cystine‐directed particles, even using electron tomography, both cases showed circular dichroism bands of opposite sign, with nearly mirrored chiroptical signatures for chiral micelle‐directed growth, along with quasi‐helical wrinkles of inverted handedness. These results expand the chiral growth toolbox with an effect that might be exploited to yield a host of interesting morphologies with tunable optical properties. | ||||
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| Language | Wos | Publication Date | 2024-05-24 | ||
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Edition | |||
| ISSN | 1433-7851 | ISBN | Additional Links | ||
| Impact Factor | 16.6 | Times cited | Open Access | ||
| Notes | Ana Sánchez-Iglesias is acknowledged for support in the synthesis of pentatwinned gold nanorods. The authors acknowledge financial support by the European Research Council (ERC CoG No. 815128 REALNANO to S.B.), from MCIN/AEI/10.13039/501100011033 (Grant PID2020- 117779RB-I00 to L.M.L.-M and FPI Fellowship PRE2021- 097588 to K.V.G.), and by KU Leuven (C14/22/085). This work has been funded by the European Union under Project 101131111—DELIGHT. Funding for open access charge: Universidade de Vigo/ CRUE-CISUG. | Approved | Most recent IF: 16.6; 2024 IF: 11.994 | ||
| Call Number | EMAT @ emat @ | Serial | 9129 | ||
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| Author | Chakraborty, J.; Chatterjee, A.; Molkens, K.; Nath, I.; Arenas Esteban, D.; Bourda, L.; Watson, G.; Liu, C.; Van Thourhout, D.; Bals, S.; Geiregat, P.; Van der Voort, P. | ||||
| Title | Decoding Excimer Formation in Covalent–Organic Frameworks Induced by Morphology and Ring Torsion | Type | A1 Journal Article | ||
| Year | 2024 | Publication | Advanced Materials | Abbreviated Journal | Advanced Materials |
| Volume | Issue | Pages | |||
| Keywords | A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; | ||||
| Abstract | A thorough and quantitative understanding of the fate of excitons in covalent–organic frameworks (COFs) after photoexcitation is essential for their augmented optoelectronic and photocatalytic applications via precise structure tuning. The synthesis of a library of COFs having identical chemical backbone with impeded conjugation, but varied morphology and surface topography to study the effect of these physical properties on the photophysics of the materials is herein reported. The variation of crystallite size and surface topography substantified different aggregation pattern in the COFs, which leads to disparities in their photoexcitation and relaxation properties. Depending on aggregation, an inverse correlation between bulk luminescence decay time and exciton binding energy of the materials is perceived. Further transient absorption spectroscopic analysis confirms the presence of highly localized, immobile, Frenkel excitons (of diameter 0.3–0.5 nm) via an absence of annihilation at high density, most likely induced by structural torsion of the COF skeletons, which in turn preferentially relaxes via long‐lived (nanosecond to microsecond) excimer formation (in femtosecond scale) over direct emission. These insights underpin the importance of structural and topological design of COFs for their targeted use in photocatalysis. | ||||
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| Language | Wos | 001206226700001 | Publication Date | 2024-04-22 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue |
Edition | |||
| ISSN | 0935-9648 | ISBN | Additional Links | UA library record; WoS full record | |
| Impact Factor | 29.4 | Times cited | Open Access | ||
| Notes | PVDV, JC, AC, and IN acknowledge the FWO-Vlaanderen for research grant G020521N and the research board of UGent (BOF) through a Concerted Research Action (GOA010-17). JC acknowledges UGent for BOF postdoctoral grant (2022.0032.01). AC acknowledges FWOVlaanderen for postdoctoral grant (12T7521N). KM, DVT and PG acknowledges FWOVlaanderen for research grant G0B2921N. SB and DAE acknowledge financial support from ERC Consolidator Grant Number 815128 REALNANO. CHL acknowledges China Scholarship Council doctoral grant (201908110280). PVDV acknowledges Hercules Project AUGE/17/07 for the UV VIS DRS spectrometer and UGent BASBOF BOF20/BAS/015 for the powder X-Ray Diffractometer. PG thanks UGent for support of the Core Facility NOLIMITS. | Approved | Most recent IF: 29.4; 2024 IF: 19.791 | ||
| Call Number | EMAT @ emat @c:irua:205967 | Serial | 9130 | ||
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| Author | Cioni, M.; Delle Piane, M.; Polino, D.; Rapetti, D.; Crippa, M.; Arslan Irmak, E.; Van Aert, S.; Bals, S.; Pavan, G.M. | ||||
| Title | Sampling real-time atomic dynamics in metal nanoparticles by combining experiments, simulations, and machine learning | Type | A1 Journal article | ||
| Year | 2024 | Publication | Advanced Science | Abbreviated Journal | |
| Volume | Issue | Pages | 1-13 | ||
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Even at low temperatures, metal nanoparticles (NPs) possess atomic dynamics that are key for their properties but challenging to elucidate. Recent experimental advances allow obtaining atomic-resolution snapshots of the NPs in realistic regimes, but data acquisition limitations hinder the experimental reconstruction of the atomic dynamics present within them. Molecular simulations have the advantage that these allow directly tracking the motion of atoms over time. However, these typically start from ideal/perfect NP structures and, suffering from sampling limits, provide results that are often dependent on the initial/putative structure and remain purely indicative. Here, by combining state-of-the-art experimental and computational approaches, how it is possible to tackle the limitations of both approaches and resolve the atomistic dynamics present in metal NPs in realistic conditions is demonstrated. Annular dark-field scanning transmission electron microscopy enables the acquisition of ten high-resolution images of an Au NP at intervals of 0.6 s. These are used to reconstruct atomistic 3D models of the real NP used to run ten independent molecular dynamics simulations. Machine learning analyses of the simulation trajectories allow resolving the real-time atomic dynamics present within the NP. This provides a robust combined experimental/computational approach to characterize the structural dynamics of metal NPs in realistic conditions. Experimental and computational techniques are bridged to unveil atomic dynamics in gold nanoparticles (NPs), using annular dark-field scanning transmission electron microscopy and molecular dynamics simulations informed by machine learning. The approach provides unprecedented insights into the real-time structural behaviors of NPs, merging state-of-the-art techniques to accurately characterize their dynamics under realistic conditions. image | ||||
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| Language | Wos | 001206888000001 | Publication Date | 2024-04-24 | |
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Edition | |||
| ISSN | 2198-3844 | ISBN | Additional Links | UA library record; WoS full record | |
| Impact Factor | 15.1 | Times cited | Open Access | ||
| Notes | This work was supported by the funding received by the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (grant agreement no. 818776- DYNAPOL, no. 770887 PICOMETRICS and no. 815128 REALNANO). The authors also acknowledge the computational resources provided by the Swiss National Supercomputing Center (CSCS), by CINECA, and the Research Foundation Flanders (FWO, Belgium) G.0346.21N. | Approved | Most recent IF: 15.1; 2024 IF: 9.034 | ||
| Call Number | UA @ admin @ c:irua:205442 | Serial | 9171 | ||
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| Author | Arisnabarreta, N.; Hao, Y.; Jin, E.; Salame, A.; Muellen, K.; Robert, M.; Lazzaroni, R.; Van Aert, S.; Mali, K.S.; De Feyter, S. | ||||
| Title | Single-layered imine-linked porphyrin-based two-dimensional covalent organic frameworks targeting CO₂ reduction | Type | A1 Journal article | ||
| Year | 2024 | Publication | Advanced energy materials | Abbreviated Journal | |
| Volume | Issue | Pages | |||
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | The reduction of carbon dioxide (CO2) using porphyrin-containing 2D covalent organic frameworks (2D-COFs) catalysts is widely explored nowadays. While these framework materials are normally fabricated as powders followed by their uncontrolled surface heterogenization or directly grown as thin films (thickness >200 nm), very little is known about the performance of substrate-supported single-layered (approximate to 0.5 nm thickness) 2D-COFs films (s2D-COFs) due to its highly challenging synthesis and characterization protocols. In this work, a fast and straightforward fabrication method of porphyrin-containing s2D-COFs is demonstrated, which allows their extensive high-resolution visualization via scanning tunneling microscopy (STM) in liquid conditions with the support of STM simulations. The as-prepared single-layered film is then employed as a cathode for the electrochemical reduction of CO2. Fe porphyrin-containing s2D-COF@graphite used as a single-layered heterogeneous catalyst provided moderate-to-high carbon monoxide selectivity (82%) and partial CO current density (5.1 mA cm(-2)). This work establishes the value of using single-layered films as heterogene ous catalysts and demonstrates the possibility of achieving high performance in CO2 reduction even with extremely low catalyst loadings. | ||||
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| Language | Wos | 001177577200001 | Publication Date | 2024-02-28 | |
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| Series Volume | Series Issue |
Edition | |||
| ISSN | 1614-6832; 1614-6840 | ISBN | Additional Links | UA library record; WoS full record | |
| Impact Factor | 27.8 | Times cited | Open Access | ||
| Notes | N.A. acknowledges a postdoctoral fellowship from the Research Foundation- Flanders (FWO) via grant 12ZS623N. S.D.F. acknowledges support from FWO (G0A4120N, G0H2122N, G0A5U24N), KU Leuven Internal Funds (grants C14/18/06, C14/19/079, C14/23/090), European Union under the Horizon Europe grant 101046231 (FantastiCOF), and M-ERA.NET via FWO (G0K9822N). S.D.F., K.M., Y.H., R.L., and S.V.A. were thankful to the FWO and FNRS for the financial support through the EOS program (grant 30489208, 40007495). Research in Mons was also supported by the Belgian National Fund for Scientific Research (FRS-FNRS) within the Consortium des Équipements de Calcul Intensif- CÉCI, and by the Walloon Region (ZENOBE and LUCIA Tier-1 supercomputers). E.J. appreciated the support from the Alexander von Humboldt Foundation, the Max Planck Society, the FLAG-ERA Grant OPERA by DFG 437130745, the National Natural Science Foundation of China (22288101), and the 111 Project (B17020). Partial financial support to M.R. from the Institut Universitaire de France (IUF) was warmly thanked. | Approved | Most recent IF: 27.8; 2024 IF: 16.721 | ||
| Call Number | UA @ admin @ c:irua:204856 | Serial | 9172 | ||
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| Author | Ni, S.; Houwman, E.; Gauquelin, N.; Chezganov, D.; Van Aert, S.; Verbeeck, J.; Rijnders, G.; Koster, G. | ||||
| Title | Stabilizing perovskite Pb(Mg0.33Nb0.67)O3-PbTiO3 thin films by fast deposition and tensile mismatched growth template | Type | A1 Journal article | ||
| Year | 2024 | Publication | ACS applied materials and interfaces | Abbreviated Journal | |
| Volume | 16 | Issue | 10 | Pages | 12744-12753 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Because of its low hysteresis, high dielectric constant, and strong piezoelectric response, Pb(Mg1/3Nb2/3)O-3-PbTiO3 (PMN-PT) thin films have attracted considerable attention for the application in PiezoMEMS, field-effect transistors, and energy harvesting and storage devices. However, it remains a great challenge to fabricate phase-pure, pyrochlore-free PMN-PT thin films. In this study, we demonstrate that a high deposition rate, combined with a tensile mismatched template layer can stabilize the perovskite phase of PMN-PT films and prevent the nucleation of passive pyrochlore phases. We observed that an accelerated deposition rate promoted mixing of the B-site cation and facilitated relaxation of the compressively strained PMN-PT on the SrTiO3 (STO) substrate in the initial growth layer, which apparently suppressed the initial formation of pyrochlore phases. By employing La-doped-BaSnO3 (LBSO) as the tensile mismatched buffer layer, 750 nm thick phase-pure perovskite PMN-PT films were synthesized. The resulting PMN-PT films exhibited excellent crystalline quality close to that of the STO substrate. | ||||
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| Language | Wos | 001176343700001 | Publication Date | 2024-02-29 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
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Edition | |||
| ISSN | 1944-8244 | ISBN | Additional Links | UA library record; WoS full record | |
| Impact Factor | 9.5 | Times cited | Open Access | ||
| Notes | We would like to acknowledge the Netherlands Organization for Scientific Research (NWO) for the financial support of this work. This project has received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement No. 823717-ESTEEM3. | Approved | Most recent IF: 9.5; 2024 IF: 7.504 | ||
| Call Number | UA @ admin @ c:irua:204754 | Serial | 9174 | ||
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| Author | Goessens, C.; Schryvers, D.; van Landuyt, J.; Geuens, I.; Gijbels, R.; Jacob, W.; de Keyzer, R. | ||||
| Title | A temperature study of mixed AgBr-AgBrI tabular crystals | Type | H1 Book chapter | ||
| Year | 1995 | Publication | Abbreviated Journal | ||
| Volume | Issue | Pages | 70-76 | ||
| Keywords | H1 Book chapter; Electron microscopy for materials research (EMAT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
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| Publisher | Place of Publication | Hawaii | Editor | ||
| Language | Wos | A1995RY19900011 | Publication Date | 0000-00-00 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | 39 | Series Issue |
1 | Edition | |
| ISSN | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | ||
| Impact Factor | Times cited | 3 | Open Access | ||
| Notes | Approved | PHYSICS, APPLIED 47/145 Q2 # | |||
| Call Number | UA @ lucian @ c:irua:8459 | Serial | 3501 | ||
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| Author | Schryvers, D.; Tanner, L.E. | ||||
| Title | On the phase-like nature of the 7m structure in ni-al | Type | P1 Proceeding | ||
| Year | 1994 | Publication | Abbreviated Journal | ||
| Volume | Issue | Pages | 849-852 | ||
| Keywords | P1 Proceeding; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
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| Publisher | Elsevier | Place of Publication | Amsterdam | Editor | |
| Language | Wos | A1994BC69J00183 | Publication Date | 0000-00-00 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | 18 | Series Issue |
A B | Edition | |
| ISSN | 0-444-81995-9 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | Times cited | 1 | Open Access | ||
| Notes | Approved | ||||
| Call Number | UA @ lucian @ c:irua:95935 | Serial | 2446 | ||
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