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Author |
Shafiei, M.; Fazileh, F.; Peeters, F.M.; Milošević, M.V. |
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Title |
Tuning the quantum phase transition of an ultrathin magnetic topological insulator |
Type |
A1 Journal article |
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Year |
2024 |
Publication |
Physical review materials |
Abbreviated Journal |
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Volume |
8 |
Issue |
7 |
Pages |
074201-74208 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We explore the effect of thickness, magnetization direction, strain, and gating on the topological quantum phase transition of a thin-film magnetic topological insulator. Reducing the film thickness to the ultrathin regime couples the edge states on the two surfaces, opening a gap known as the hybridization gap, and causing a phase transition from a topological insulator to a normal insulator (NI). An out-of-plane/in-plane magnetization of size proportional to the hybridization gap triggers a phase transition from a normal insulator state to a quantum anomalous Hall (QAH)/semimetal state. A magnetization tilt by angle 0 from the out-of-plane axis influences the topological phase transition in a way that for sufficiently large 0, no phase transition from NI to QAH can be observed regardless of the sample thickness or magnetization, and for 0 close to pi /2 the system transits to a semimetal phase. Furthermore, we demonstrate that compressive/tensile strain can be used to decrease/increase the magnetization threshold for the topological phase transition. Finally, we reveal the effect of a vertical potential acting on the film, be it due to the substrate or applied gating, which breaks inversion symmetry and raises the magnetization threshold for the transition from NI to QAH state. |
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Wos |
https://www.webofscience.com/api/gateway?GWVersion=2&SrcApp=brocade2&SrcAuth=WosAPI&KeyUT=WOS:001281 |
Publication Date |
2024-07-25 |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2475-9953 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
3.4 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 3.4; 2024 IF: NA |
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Call Number |
UA @ admin @ c:irua:207598 |
Serial  |
9324 |
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Author |
Hoekx, S.; Daems, N.; Arenas Esteban, D.; Bals, S.; Breugelmans, T. |
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Title |
Toward the rational design of Cu electrocatalysts for improved performance of the NO3RR |
Type |
A1 Journal article |
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Year |
2024 |
Publication |
ACS applied energy materials |
Abbreviated Journal |
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Volume |
7 |
Issue |
9 |
Pages |
3761-3775 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT) |
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Abstract |
Cu is one of the most promising materials as an electrocatalyst for the nitrate reduction reaction (NO3RR) to ammonia, a reaction that can simultaneously remove nitrates from wastewater and produce ammonia, a high-value commodity chemical. However, a rational approach to catalyst design is lacking, limiting efficient catalyst optimization. In this work, we propose a way to synthesize monodisperse, polycrystalline Cu NPs with small variances in size by changing the carbon chain length of the phosphonic acid-based ligand. Cu NPs with 8.3, 10.0, and 11.9 nm diameters are successfully synthesized, and high-resolution electron microscopy and tomography are used to characterize these NPs in depth. By isolating Cu NP size as a parameter, we can unequivocally establish its effect on electrochemical performance for the NO3RR to ammonia under optimal operating conditions for the catalyst (0.1 M KOH electrolyte at -1.25 V vs RHE, as established in the first phase). The smallest Cu NPs (8.3 nm with a TDPA ligand) perform best, achieving Faradaic efficiencies (FEs) of 85.4% and absolute current densities of similar to 250 mA cm(-2), with increasing current densities and constant FEs as the particle size decreases. To allow for a rational approach to Cu-based catalyst design from a stability perspective, this work completed a first study of the main degradation pathway that the Cu NPs undergo during NO3RR. High-resolution electron microscopy and tomography are used to characterize the particles at various stages of the reaction. The NPs undergo agglomeration, pulverization, and particle detachment due to the reaction, starting at a particle size of 8.3 nm and progressively getting smaller, but leveling off, until a NP size of 2.6 nm is reached after 2 h of electrolysis. This decrease in NP size goes paired with a decrease in FE from 83% after the first 15 min to 74% after 2 h at -0.75 V vs RHE, despite the increase in active surface area. These insights into the most prominent degradation mechanisms allow for rational adjustments to future catalysts to combat these changes; for example, by embedding NPs in a tailored support, morphological degradation could be impeded. Therefore, these insights allow for a rational approach to the improvement of the stability of Cu-based catalysts for the NO3RR, a very important but often an overlooked aspect of catalyst design. |
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Wos |
001228056800001 |
Publication Date |
2024-04-30 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2574-0962 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
6.4 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 6.4; 2024 IF: NA |
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Call Number |
UA @ admin @ c:irua:206469 |
Serial |
9323 |
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Author |
Gonzalez-Garcia, A.; Bacaksiz, C.; Frauenheim, T.; Milošević, M.V. |
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Title |
Strong spin-lattice coupling and high-temperature magnetic ordering in monolayer chromium dichalcogenides |
Type |
A1 Journal article |
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Year |
2024 |
Publication |
Physical review materials |
Abbreviated Journal |
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Volume |
8 |
Issue |
6 |
Pages |
064001-64009 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We detail the magnetic properties of monolayer CrX2 and its Janus counterparts CrXY (X, Y = S, Se, Te, with X not equal Y) using ab initio methods and Landau-Lifshitz-Gilbert magnetization dynamics, and uncover the pronouncedly strong interplay between their structure symmetry and the magnetic order. The relaxation of nonmagnetic chalcogen atoms, that carry large spin-orbit coupling, changes the energetically preferential magnetic order between in-plane antiferromagnetic and tilted ferromagnetic one. The considered Janus monolayers exhibit sizable Dzyaloshinskii-Moriya interaction, in some cases above 20% of the isotropic exchange, and critical temperature of the long-range magnetic order in the vicinity or even significantly above the room temperature. |
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Wos |
001247462600001 |
Publication Date |
2024-06-13 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2475-9953 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
3.4 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 3.4; 2024 IF: NA |
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Call Number |
UA @ admin @ c:irua:206660 |
Serial |
9317 |
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Author |
Yari, S.; Bird, L.; Rahimisheikh, S.; Reis, A.C.; Mohammad, M.; Hadermann, J.; Robinson, J.; Shearing, P.R.; Safari, M. |
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Title |
Probing charge transport and microstructural attributes in solvent- versus water-based electrodes with a spotlight on Li-S battery cathode |
Type |
A1 Journal article |
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Year |
2024 |
Publication |
Advanced energy materials |
Abbreviated Journal |
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Volume |
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Issue |
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Pages |
2402163 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
In the quest for environmentally benign battery technologies, this study examines the microstructural and transport properties of water-processed electrodes and compares them to conventionally formulated electrodes using the toxic solvent, N-Methyl-2-pyrrolidone (NMP). Special focus is placed on sulfur electrodes utilized in lithium-sulfur batteries for their sustainability and compatibility with diverse binder/solvent systems. The characterization of the electrodes by X-ray micro-computed tomography reveals that in polyvinylidene fluoride (PVDF) Lithium bis(trifluoromethanesulfonyl)imide/NMP, sulfur particles tend to remain in large clusters but break down into finer particles in carboxymethyl cellulose-styrene butadiene rubber (CMC-SBR)/water and lithium polyacrylate (LiPAA)/water dispersions. The findings reveal that in the water-based electrodes, the binder properties dictate the spatial arrangement of carbon particles, resulting in either thick aggregates with short-range connectivity or thin films with long-range connectivity among sulfur particles. Additionally, cracking is found to be particularly prominent in thicker water-based electrodes, propagating especially in regions with larger particle agglomerates and often extending to cause local delamination of the electrodes. These microstructural details are shown to significantly impact the tortuosity and contact resistance of the sulfur electrodes and thereby affecting the cycling performance of the Li-S battery cells. The choice of solvent and binder is crucial in determining particle surface charge, which directly influences active material dispersion and carbon-binder arrangement within the battery porous electrodes. This, in turn, affects ionic and electronic transport properties, ultimately impacting electrochemical performance. Meticulous engineering of the slurry to control these factors is essential for efficient and sustainable water-based electrode processing. image |
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Wos |
https://www.webofscience.com/api/gateway?GWVersion=2&SrcApp=brocade2&SrcAuth=WosAPI&KeyUT=WOS:001291 |
Publication Date |
2024-08-16 |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1614-6832; 1614-6840 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
27.8 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 27.8; 2024 IF: 16.721 |
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Call Number |
UA @ admin @ c:irua:207624 |
Serial |
9311 |
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Author |
Kandemir, Z.; D'Amico, P.; Sesti, G.; Cardoso, C.; Milošević, M.V.; Sevik, C. |
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Title |
Optical properties of metallic MXene multilayers through advanced first-principles calculations |
Type |
A1 Journal article |
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Year |
2024 |
Publication |
Physical review materials |
Abbreviated Journal |
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Volume |
8 |
Issue |
7 |
Pages |
075201-75210 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Having a strong electromagnetic absorption, MXene multilayers are readily envisaged for applications in electromagnetic shields and related prospective technology. However, an ab initio characterization of the optical properties of MXenes is still lacking, due in part to major difficulties with the treatment of metallicity in the first-principles approaches. Here we addressed the latter challenge, after a careful treatment of intraband transitions, to present a thorough analysis of the electronic and optical properties of a selected set of metallic MXene layers based on density functional theory (DFT) and many-body perturbation theory calculations. Our results reveal that the GW corrections are particularly important in regions of the band structure where d and p states hybridize. For some systems, we show that GW corrections open a gap between occupied states, resulting in a band structure that closely resembles that of an intrinsic transparent conductor, thereby opening an additional line of prospective applications for the MXenes family. Nevertheless, GW and Bethe-Salpeter corrections have a minimal influence on the absorption spectra, in contrast to what is typically observed in semiconductor layers. Our present results suggest that calculations within the independent particle approximation (IPA) calculations are sufficiently accurate for assessing the optical characteristics of bulk-layered MXene materials. Finally, our calculated dielectric properties and absorption spectra, in agreement with existing experimental data, confirm the potential of MXenes as effective infrared emitters. |
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Wos |
https://www.webofscience.com/api/gateway?GWVersion=2&SrcApp=brocade2&SrcAuth=WosAPI&KeyUT=WOS:001275 |
Publication Date |
2024-07-22 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2475-9953 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
3.4 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 3.4; 2024 IF: NA |
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Call Number |
UA @ admin @ c:irua:207597 |
Serial |
9309 |
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Author |
Tian, X.; Xie, X.; Li, J.; Kong, X.; Gong, W.-J.; Peeters, F.M.; Li, L. |
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Title |
Multiferroic ScLaX₂ (X = P, As, and Sb) monolayers : bidirectional negative Poisson's ratio effects and phase transformations driven by rare-earth (main-group) elements |
Type |
A1 Journal article |
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Year |
2024 |
Publication |
Physical review materials |
Abbreviated Journal |
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Volume |
8 |
Issue |
8 |
Pages |
084407-84411 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
The combination of auxetic property, ferroelasticity, and ferroelectricity in two-dimensional materials offers new avenues for next-generation multifunctional devices. However, two-dimensional materials that simultaneously exhibit those properties are rarely reported. Here, we present a class of two-dimensional Janus-like structures ScLaX2 X 2 (X X = P, As, and Sb) with a rectangular lattice based on first-principles calculations. We predict that those ScLaX2 X 2 monolayers are stable semiconductors with both intrinsic in-plane and out-of-plane auxetic properties, showing a bidirectional negative Poisson's ratio effect. The value of the out-of-plane negative Poisson's ratio effect can reach – 2.28 /- 3.06 /- 3.89. By applying uniaxial strain engineering, two transition paths can be found, including the VA main group element path and the rare-earth metal element path, corresponding to the ferroelastic and the multiferroic (ferroelastic and ferroelectric) phase transition, respectively. For the ScLaSb2 2 monolayer, the external force field can not only control the ferroelastic phase transition, but it can also lead to the reversal of the out-of-plane polarization, exhibiting potential multiferroicity. The coupling between the bidirectional negative Poisson's ratio effect and multiferroicity makes the ScLaX2 X 2 monolayers promising for future device applications. |
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Wos |
https://www.webofscience.com/api/gateway?GWVersion=2&SrcApp=brocade2&SrcAuth=WosAPI&KeyUT=WOS:001293 |
Publication Date |
2024-08-13 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2475-9953 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
3.4 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 3.4; 2024 IF: NA |
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Call Number |
UA @ admin @ c:irua:207592 |
Serial |
9306 |
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Author |
Folkers, B.; Jansen, T.; Roskamp, T.J.; Reith, P.; Timmermans, A.; Jannis, D.; Gauquelin, N.; Verbeeck, J.; Hilgenkamp, H.; Rosario, C.M.M. |
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Title |
Imaging the suppression of ferromagnetism in LaMnO₃ by metallic overlayers |
Type |
A1 Journal article |
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Year |
2024 |
Publication |
Physical review materials |
Abbreviated Journal |
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Volume |
8 |
Issue |
5 |
Pages |
054408-6 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
LaMnO 3 (LMO) thin films epitaxially grown on SrTiO 3 (STO) usually exhibit ferromagnetism above a critical layer thickness. We report the use of scanning SQUID microscopy (SSM) to study the suppression of the ferromagnetism in STO / LMO / metal structures. By partially covering the LMO surface with a metallic layer, both covered and uncovered LMO regions can be studied simultaneously. While Au does not significantly influence the ferromagnetic order of the underlying LMO film, a thin Ti layer induces a strong suppression of the ferromagnetism, over tens of nanometers, which increases with time on a timescale of days. Detailed electron energy loss spectroscopy analysis of the Ti-LaMnO 3 interface reveals the presence of Mn 2 + and an evolution of the Ti valence state from Ti 0 to Ti 4 + over approximately 5 nm. Furthermore, we demonstrate that by patterning Ti / Au overlayers, we can locally suppress the ferromagnetism and define ferromagnetic structures down to sub -micrometer scales. |
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Wos |
001239765800005 |
Publication Date |
2024-05-13 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2475-9953 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
3.4 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 3.4; 2024 IF: NA |
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Call Number |
UA @ admin @ c:irua:206555 |
Serial |
9297 |
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Author |
Šoškić, B.N.; Bekaert, J.; Sevik, C.; Šljivančanin, Ž.; Milošević, M.V. |
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Title |
First-principles exploration of superconductivity in intercalated bilayer borophene phases |
Type |
A1 Journal article |
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Year |
2024 |
Publication |
Physical review materials |
Abbreviated Journal |
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Volume |
8 |
Issue |
6 |
Pages |
064803-64811 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We explore the emergence of phonon-mediated superconductivity in bilayer borophenes by controlled intercalation with elements from the groups of alkali, alkaline-earth, and transition metals, using systematic first-principles and Eliashberg calculations. We show that the superconducting properties are primarily governed by the interplay between the out-of-plane (????????) boron states and the partially occupied in-plane (????+????????,????) bonding states at the Fermi level. Our Eliashberg calculations indicate that intercalation with alkaline-earth-metal elements leads to the highest superconducting critical temperatures (????????). Specifically, Be in ????4, Mg in ????3, and Ca in the kagome bilayer borophene demonstrate superior performance with ???????? reaching up to 58 K. Our study therefore reveals that intercalated bilayer borophene phases are not only more resilient to chemical deterioration, but also harbor enhanced ???????? values compared to their monolayer counterparts, underscoring their substantial potential for the development of boron-based two-dimensional superconductors. |
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Wos |
https://www.webofscience.com/api/gateway?GWVersion=2&SrcApp=brocade2&SrcAuth=WosAPI&KeyUT=WOS:001254 |
Publication Date |
2024-06-24 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2475-9953 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
3.4 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 3.4; 2024 IF: NA |
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Call Number |
UA @ admin @ c:irua:206919 |
Serial |
9290 |
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Author |
Huang, S.; Houwman, E.; Gauquelin, N.; Orekhov, A.; Chezganov, D.; Verbeeck, J.; Hu, S.; Zhong, G.; Koster, G.; Rijnders, G. |
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Title |
Enhanced piezoelectricity by polarization rotation through thermal strain manipulation in PbZr0.6Ti0.4O3 thin films |
Type |
A1 Journal article |
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Year |
2024 |
Publication |
Advanced Materials Interfaces |
Abbreviated Journal |
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Volume |
11 |
Issue |
19 |
Pages |
2400048-2400049 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Lead based bulk piezoelectric materials, e.g., PbZrxTi1-xO3 (PZT), are widely used in electromechanical applications, sensors, and transducers, for which optimally performing thin films are needed. The results of a multi-domain Landau-Ginzberg-Devonshire model applicable to clamped ferroelectric thin films are used to predict the lattice symmetry and properties of clamped PZT thin films on different substrates. Guided by the thermal strain phase diagrams that are produced by this model, experimentally structural transitions are observed. These can be related to changes of the piezoelectric properties in PZT(x = 0.6) thin films that are grown on CaF2, SrTiO3 (STO) and 70% PbMg1/3Nb2/3O3-30% PbTiO3 (PMN-PT) substrates by pulsed laser deposition. Through temperature en field dependent in situ X-ray reciprocal space mapping (RSMs) and piezoelectric force microscopy (PFM), the low symmetry monoclinic phase and polarization rotation are observed in the film on STO and can be linked to the measured enhanced properties. The study identifies a monoclinic -rhombohedral M-C-M-A-R crystal symmetry path as the polarization rotation mechanism. The films on CaF2 and PMN-PT remain in the same symmetry phase up to the ferroelectric-paraelectric phase transition, as predicted. These results support the validity of the multi-domain model which provides the possibility to predict the behavior of clamped, piezoelectric PZT thin films, and design films with enhanced properties. |
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Wos |
001240425700001 |
Publication Date |
2024-06-07 |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2196-7350 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
5.4 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 5.4; 2024 IF: 4.279 |
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Call Number |
UA @ admin @ c:irua:206593 |
Serial |
9287 |
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Author |
Kocabas, T.; Samanta, B.; Barboza, E. da S.; Sevik, C.; Milošević, M.V.; Çakir, D. |
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Title |
Electron-phonon coupling and thermal conductivity of MAB compounds |
Type |
A1 Journal article |
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Year |
2024 |
Publication |
Physical review materials |
Abbreviated Journal |
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Volume |
8 |
Issue |
5 |
Pages |
055002-55011 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We investigated the electron-phonon ( e -ph ) coupling and vibrational thermal conductivity in the representative MAB compounds, namely MoAlB, WAlB, Tc 2 AlB 2 , and Cr 2 AlB 2 . The spectral distribution functions of e -ph interaction, obtained through ab initio linear-response calculations, reveal that the electron-phonon coupling values range from low (0.15) to moderate (0.58). With such e -ph coupling, out of the considered compounds, only Tc 2 AlB 2 exhibits a superconducting transition, at 4 K. We further evaluated the thermal conductivity and associated properties like scattering rates, obtained using ab initio and other methodologies. The latter included the iterative solution of the Peierls-Boltzmann transport equation, using HIPHIVE package for advanced optimization and machine learning techniques, and employing maximum likelihood estimation to approximate scattering rates from a limited set of scattering processes. We found that these methods yield nearly identical predictions for thermal conductivity values, with a significant decrease in the computational cost compared to the first-principles methods. We examined interactions arising from both three-phonon (3 ph ) and four -phonon (4 ph ) scattering processes. The 4 ph interactions demonstrated a smaller yet significant impact on the overall vibrational thermal conductivity, most notably in Tc 2 AlB 2 . Our findings indicate that Cr 2 AlB 2 has the highest thermal conductivity across all considered crystal directions, with the thermal conductivity being spatially anisotropic, most pronouncedly in Tc 2 AlB 2 . Finally, we show that empirical expressions based on Slack models are well suited for screening the thermal conductivity properties of MAB phases, and can be employed to establish upper and lower limits of their thermal conductivity. |
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Wos |
001231927600005 |
Publication Date |
2024-05-21 |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2475-9953 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
3.4 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 3.4; 2024 IF: NA |
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Call Number |
UA @ admin @ c:irua:206590 |
Serial |
9286 |
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| Permanent link to this record |
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Author |
Van Daele, K.; Balalta, D.; Hoekx, S.; Jacops, R.; Daems, N.; Altantzis, T.; Pant, D.; Breugelmans, T. |
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Title |
Synergy or Antagonism? Exploring the Interplay of SnO2and an N-OMC Carbon Capture Medium for the Electrochemical CO2Reduction toward Formate |
Type |
A1 Journal Article |
| |
Year |
2024 |
Publication |
ACS Applied Energy Materials |
Abbreviated Journal |
ACS Appl. Energy Mater. |
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| |
Volume |
7 |
Issue |
13 |
Pages |
5517-5527 |
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Keywords |
A1 Journal Article; nitrogen-doped ordered mesoporous carbon, SnO2, degradation pathways, electrochemical CO2 reduction, formate; Electron Microscopy for Materials Science (EMAT) ; |
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Abstract |
Closing the anthropogenic carbon cycle by means of the sustainable electrochemical CO2 reduction (eCO2R) toward formate (FA) is a promising strategy for CO2 abatement, clearing the path toward a carbon neutral future. Currently, three possible reaction pathways have been identified for the eCO2R toward FA, all of which are initiated by the adsorption of CO2 on the electrocatalyst’s surface. Therefore, a possible strategy to enhance the availability of CO2 near the active sites is to combine an active electrocatalyst material (here, SnO2) with a known carbon capture medium (here, nitrogen-doped ordered mesoporous carbon (N-OMC)). SnO2 was introduced in situ during the N-OMC synthesis, yielding SnO2-N-OMCs. We approached the state of the art for Sn-based N-doped carbon electrocatalysts in terms of performance under industrially relevant currents with an average FEFA of 59% for SnO2-N-OMC (6) and 61% for SnO2-N-OMC (2). Moreover, the SnO2-N-OMC electrocatalysts require a low overpotential, courtesy of the N-OMC support, compared to the state of the art, for the selective conversion of CO2 toward FA at the industrially relevant current density of 100 mA cm–2. Additionally, the 24 h stability of the best performing SnO2-N-OMC electrocatalysts is explored, and pulverization/agglomeration and in situ SnO2 reduction are identified as major degradation pathways, allowing future research to be steered more accurately toward more stable Sn-based electrocatalysts for the eCO2R toward FA. An optimal combination of both the SnO2 species and the N-OMC carbon capture medium could result in a synergistic effect, especially when utilization of the N-OMC support material is optimized to morphologically stabilize the SnO2 active species. |
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Wos |
https://www.webofscience.com/api/gateway?GWVersion=2&SrcApp=brocade2&SrcAuth=WosAPI&KeyUT=WOS:001253 |
Publication Date |
2024-07-08 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2574-0962 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
6.4 |
Times cited |
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Open Access |
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Notes |
K.V.D. received financial support through a PhD fellowship strategic basic research (1S83320N) from the Research Foundation Flanders (FWO). Additionally, this project received funding in the framework of the Catalisti cluster SBO project CO2PERATE (“All renewable CCU based on formic acid integrated in an industrial micro-grid”), with financial support of VLAIO (Flemish Agency for Innovation and Entrepreneurship) (UA & VITO). Furthermore, this research was supported by the Interreg 2 Seas-program 2014–2020, cofunded by the European Regional Development Fund under subsidy contract no. E2C 2S03-019 (UA & VITO). D.B. and D.P. acknowledge the support from European Union’s Horizon 2020 MSCA-ITN programme under grant agreement no. 955650 (CATCHY). S.H. is financially supported through a PhD fellowship strategic basic research (1S42623N) from the Research Foundation Flanders (FWO). R.J. received financial support of the federal Energy Transition Fund by FPS Economy. T.A. acknowledges funding from the University of Antwerp Research fund (BOF). We acknowledge Prof. Tom Hauffman and Kitty Baert from the Electrochemical and Surface Engineering research group (SURF) at the VUB (Vrije Universiteit Brussel) for the XPS measurements, Prof. Christophe Vande Velde from the Intelligence in Processes, Advanced Catalysts and Solvents (iPRACS, UAntwerp) research group for the XRD analysis, and Prof. Pegie Cool, Prof. Vera Meynen, and Radu-George Ciocarlan from the Laboratory of Adsorption and Catalysis (LADCA, UAntwerp) for the nitrogen physisorption and Raman spectroscopy measurements. |
Approved |
Most recent IF: 6.4; 2024 IF: NA |
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Call Number |
EMAT @ emat @c:irua:206409 |
Serial |
9261 |
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| Permanent link to this record |
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Author |
Chowdhury, M.S.; Esteban, D.A.; Amin, R.; Román-Freijeiro, C.; Rösch, E.L.; Etzkorn, M.; Schilling, M.; Ludwig, F.; Bals, S.; Salgueiriño, V.; Lak, A. |
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Title |
Organic Molecular Glues to Design Three-Dimensional Cubic Nano-assemblies of Magnetic Nanoparticles |
Type |
A1 Journal Article |
| |
Year |
2024 |
Publication |
Chemistry of Materials |
Abbreviated Journal |
Chem. Mater. |
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Volume |
36 |
Issue |
14 |
Pages |
6865-6876 |
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Keywords |
A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; |
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Wos |
https://www.webofscience.com/api/gateway?GWVersion=2&SrcApp=brocade2&SrcAuth=WosAPI&KeyUT=WOS:001275 |
Publication Date |
2024-07-23 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0897-4756 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
8.6 |
Times cited |
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Open Access |
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Notes |
Ministerio de Ciencia e Innovaci?n, PID2020-119242-I00 ; Deutsche Forschungsgemeinschaft, LA 4923/3-1 RTG 1952 ; Horizon 2020 Framework Programme, 823717 ; |
Approved |
Most recent IF: 8.6; 2024 IF: 9.466 |
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Call Number |
EMAT @ emat @c:irua:207594 |
Serial |
9258 |
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Author |
Quintelier, M.; Hajizadeh, A.; Zintler, A.; Gonçalves, B.F.; Fernández de Luis, R.; Esrafili Dizaji, L.; Vande Velde, C.M.L.; Wuttke, S.; Hadermann, J. |
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Title |
In SituStudy of the Activation Process of MOF-74 Using Three-Dimensional Electron Diffraction |
Type |
A1 Journal Article |
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Year |
2024 |
Publication |
Chemistry of Materials |
Abbreviated Journal |
Chem. Mater. |
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Volume |
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Issue |
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Pages |
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Keywords |
A1 Journal Article; 3DED; MOFs; in situ; Electron Microscopy for Materials Science (EMAT) ; |
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Abstract |
Metal–organic framework (MOF)-74 is known for its effectiveness in selectively capturing carbon dioxide (CO2). Especially the Zn and Cu versions of MOF-74 show high efficiency of this material for CO2. However, the activation of this MOF, which is a crucial step for its utilization, is so far not well understood. Here, we are closing the knowledge gap by examining the activation using, for the first time in the MOF, three-dimensional electron diffraction (3DED) during in situ heating. The use of state-of-the-art direct electron detectors enables rapid acquisition and minimal exposure times, therefore minimizing beam damage to the very electron beam-sensitive MOF material. The activation process of Zn-MOF-74 and Cu-MOF-74 is systematically studied in situ, proving the creation of open metal sites. Differences in thermal stability between Zn-MOF-74 and Cu-MOF-74 are attributed to the strength of the metal–oxygen bonds and Jahn–Teller distortions. In the case of Zn-MOF-74, we observe previously unknown remaining electrostatic potentials inside the MOF pores, which indicate the presence of remaining atoms that might impede gas flow throughout the structure when using the MOF for absorption purposes. We believe our study exemplifies the significance of employing advanced characterization techniques to enhance our material understanding, which is a crucial step for unlocking the full potential of MOFs in various applications. |
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Wos |
https://www.webofscience.com/api/gateway?GWVersion=2&SrcApp=brocade2&SrcAuth=WosAPI&KeyUT=WOS:001275 |
Publication Date |
2024-07-22 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0897-4756 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
8.6 |
Times cited |
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Open Access |
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Notes |
European Regional Development Fund, PID2021-122940OB-C31 ; H2020 Energy, 101022633 ; Universiteit Antwerpen, BOF TOP 38689 ; H2020 Marie Sklodowska-Curie Actions, 956099 ; Fonds Wetenschappelijk Onderzoek, I003218N ; Japan Science and Technology Agency, JPMJSC2102 ; Funda??o de Amparo ? Pesquisa do Estado de S?o Paulo; Agencia Estatal de Investigaci?n,Ministerio de Ciencia, Innovaci?n y Universidades, PID2021-122940OB-C31 TED2021-130621B-C42 ; |
Approved |
Most recent IF: 8.6; 2024 IF: 9.466 |
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Call Number |
EMAT @ emat @c:irua:207555 |
Serial |
9255 |
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Author |
Arts, I.; Saniz, R.; Baldinozzi, G.; Leinders, G.; Verwerft, M.; Lamoen, D. |
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Title |
Ab initio study of the adsorption of O, O2, H2O and H2O2 on UO2 surfaces using DFT+U and non-collinear magnetism |
Type |
A1 Journal Article |
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Year |
2024 |
Publication |
Journal of Nuclear Materials |
Abbreviated Journal |
Journal of Nuclear Materials |
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Volume |
599 |
Issue |
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Pages |
155249 |
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Keywords |
A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; |
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Abstract |
In order to model correctly the corrosion of spent nuclear fuel under disposal conditions, it is important to understand its behavior in the presence of oxidants. To advance in this direction, we consider the oxidation of UO2. We investigate computationally the adsorption of various species on its three most stable surfaces: (111), (110), and (100), with emphasis on incorporating a full non-collinear PBE+U approach. Various species, namely O, O2, H2O and H2O2 are considered due to their relevance for the oxidation of UO2. The dissociation energy and an estimate for the dissociation barrier for O2 were obtained, using the preferred adsorption configurations of O and O2. The adsorption configurations for H2O in our study compare well with previous studies that used collinear approximations, both in terms of relative stability of configurations and bond lengths. Differences in adsorption energies were found, which may be important for reaction kinetics. Dissociative reactions in which the water molecule splits in hydrogen and hydroxyl occur only on one of the three surfaces. The hydrogen further reacts with a surface oxygen to also form a hydroxyl group. Not surprisingly, we find that H2O2 binds more strongly to the three surfaces than water (lower formation energy), and similar to H2O adsorption, dissociative reactions may occur. The dissociated hydrogen reacts with a surface oxygen to form a hydroxyl group and the hydroperoxyl molecule binds with a surface uranium. Our study, which includes a detailed study of electron transfer, magnetic structure and the preferred adsorption configurations, gives insight into the uranium oxidation states and the influence of surface geometry on adsorption. The findings contribute to a more comprehensive understanding of the early stages of UO2 oxidation. |
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Wos |
https://www.webofscience.com/api/gateway?GWVersion=2&SrcApp=brocade2&SrcAuth=WosAPI&KeyUT=WOS:001262 |
Publication Date |
2024-06-25 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0022-3115 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS full record |
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Impact Factor |
3.1 |
Times cited |
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Open Access |
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Notes |
Financial support for this research was provided by the Energy Transition Fund of the Belgian FPS Economy (Project SF-CORMOD: Spent Fuel – Corrosion modeling). This work was performed using HPC resources from the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the FWO-Vlaanderen and the Flemish Government department EWI (Economie, Wetenschap & Innovatie). |
Approved |
Most recent IF: 3.1; 2024 IF: 2.048 |
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Call Number |
EMAT @ emat @c:irua:207055 |
Serial |
9249 |
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Author |
Hassani, N.; Movafegh-Ghadirli, A.; Mahdavifar, Z.; Peeters, F.M.; Neek-Amal, M. |
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Title |
Two new members of the covalent organic frameworks family : crystalline 2D-oxocarbon and 3D-borocarbon structures |
Type |
A1 Journal article |
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Year |
2024 |
Publication |
Computational materials science |
Abbreviated Journal |
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Volume |
241 |
Issue |
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Pages |
1-9 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Oxocarbons, known for over two centuries, have recently revealed a long-awaited facet: two-dimensional crystalline structures. Employing an intelligent global optimization algorithm (IGOA) alongside densityfunctional calculations, we unearthed a quasi -flat oxocarbon (C 6 0 6 ), featuring an oxygen -decorated hole, and a novel 3D-borocarbon. Comparative analyses with recently synthesized isostructures, such as 2D -porous carbon nitride (C 6 N 6 ) and 2D -porous boroxine (B 6 0 6 ), highlight the unique attributes of these compounds. All structures share a common stoichiometry of X 6 Y 6 (which we call COF-66), where X = B, C, and Y = B, N, O (with X not equal Y), exhibiting a 2D -crystalline structure, except for borocarbon C 6 B 6 , which forms a 3D crystal. In our comprehensive study, we conducted a detailed exploration of the electronic structure of X 6 Y 6 compounds, scrutinizing their thermodynamic properties and systematically evaluating phonon stability criteria. With expansive surface areas, diverse pore sizes, biocompatibility, pi-conjugation, and distinctive photoelectric properties, these structures, belonging to the covalent organic framework (COF) family, present enticing prospects for fundamental research and hold potential for biosensing applications. |
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Wos |
001215960700001 |
Publication Date |
2024-04-23 |
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Series Editor |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0927-0256 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
3.3 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 3.3; 2024 IF: 2.292 |
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Call Number |
UA @ admin @ c:irua:206005 |
Serial |
9179 |
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Author |
Ni, S.; Houwman, E.; Gauquelin, N.; Chezganov, D.; Van Aert, S.; Verbeeck, J.; Rijnders, G.; Koster, G. |
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Title |
Stabilizing perovskite Pb(Mg0.33Nb0.67)O3-PbTiO3 thin films by fast deposition and tensile mismatched growth template |
Type |
A1 Journal article |
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Year |
2024 |
Publication |
ACS applied materials and interfaces |
Abbreviated Journal |
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Volume |
16 |
Issue |
10 |
Pages |
12744-12753 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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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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Wos |
001176343700001 |
Publication Date |
2024-02-29 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1944-8244 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
9.5 |
Times cited |
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Open Access |
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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 |
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Call Number |
UA @ admin @ c:irua:204754 |
Serial |
9174 |
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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. |
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Title |
Single-layered imine-linked porphyrin-based two-dimensional covalent organic frameworks targeting CO₂ reduction |
Type |
A1 Journal article |
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Year |
2024 |
Publication |
Advanced energy materials |
Abbreviated Journal |
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Volume |
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Issue |
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Pages |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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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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Wos |
001177577200001 |
Publication Date |
2024-02-28 |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1614-6832; 1614-6840 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
27.8 |
Times cited |
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Open Access |
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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 |
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Call Number |
UA @ admin @ c:irua:204856 |
Serial |
9172 |
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Author |
Tiwari, S.; Van de Put, M.; Sorée, B.; Hinkle, C.; Vandenberghe, W.G. |
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Title |
Reduction of magnetic interaction due to clustering in doped transition-metal dichalcogenides : a case study of Mn-, V-, and Fe-doped WSe₂ |
Type |
A1 Journal article |
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Year |
2024 |
Publication |
ACS applied materials and interfaces |
Abbreviated Journal |
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Volume |
16 |
Issue |
4 |
Pages |
4991-4998 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
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Abstract |
Using Hubbard-U-corrected density functional theory calculations, lattice Monte Carlo simulations, and spin Monte Carlo simulations, we investigate the impact of dopant clustering on the magnetic properties of WSe2 doped with period four transition metals. We use manganese (Mn) and iron (Fe) as candidate n-type dopants and vanadium (V) as the candidate p-type dopant, substituting the tungsten (W) atom in WSe2. Specifically, we determine the strength of the exchange interaction in Fe-, Mn-, and V-doped WSe2 in the presence of clustering. We show that the clusters of dopants are energetically more stable than discretely doped systems. Further, we show that in the presence of dopant clustering, the magnetic exchange interaction significantly reduces because the magnetic order in clustered WSe2 becomes more itinerant. Finally, we show that the clustering of the dopant atoms has a detrimental effect on the magnetic interaction, and to obtain an optimal Curie temperature, it is important to control the distribution of the dopant atoms. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
001155511900001 |
Publication Date |
2024-01-18 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
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| |
ISSN |
1944-8244 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
9.5 |
Times cited |
|
Open Access |
|
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| |
Notes |
|
Approved |
Most recent IF: 9.5; 2024 IF: 7.504 |
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| |
Call Number |
UA @ admin @ c:irua:203830 |
Serial |
9169 |
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| Permanent link to this record |
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| |
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Author |
Joy, R.M.; Pobedinskas, P.; Bourgeois, E.; Chakraborty, T.; Goerlitz, J.; Herrmann, D.; Noel, C.; Heupel, J.; Jannis, D.; Gauquelin, N.; D'Haen, J.; Verbeeck, J.; Popov, C.; Houssiau, L.; Becher, C.; Nesladek, M.; Haenen, K. |
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| |
Title |
Photoluminescence of germanium-vacancy centers in nanocrystalline diamond films : implications for quantum sensing applications |
Type |
A1 Journal article |
| |
Year |
2024 |
Publication |
ACS applied nano materials |
Abbreviated Journal |
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| |
Volume |
7 |
Issue |
4 |
Pages |
3873-3884 |
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| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
Point defects in diamond, promising candidates for nanoscale pressure- and temperature-sensing applications, are potentially scalable in polycrystalline diamond fabricated using the microwave plasma-enhanced chemical vapor deposition (MW PE CVD) technique. However, this approach introduces residual stress in the diamond films, leading to variations in the characteristic zero phonon line (ZPL) of the point defect in diamond. Here, we report the effect of residual stress on germanium-vacancy (GeV) centers in MW PE CVD nanocrystalline diamond (NCD) films fabricated using single crystal Ge as the substrate and solid dopant source. GeV ensemble formation indicated by the zero phonon line (ZPL) at similar to 602 nm is confirmed by room temperature (RT) photoluminescence (PL) measurements. PL mapping results show spatial nonuniformity in GeV formation along with other defects, including silicon-vacancy centers in the diamond films. The residual stress in NCD results in shifts in the PL peak positions. By estimating a stress shift coefficient of (2.9 +/- 0.9) nm/GPa, the GeV PL peak position in the NCD film is determined to be between 598.7 and 603.2 nm. A larger ground state splitting due to the strain on a GeV-incorporated NCD pillar at a low temperature (10 K) is also reported. We also report the observation of intense ZPLs at RT that in some cases could be related to low Ge concentration and the surrounding crystalline environment. In addition, we also observe thicker microcrystalline diamond (MCD) films delaminate from the Ge substrate due to film residual stress and graphitic phase at the diamond/Ge substrate interface (confirmed by electron energy loss spectroscopy). Using this approach, a free-standing color center incorporated MCD film with dimensions up to 1 x 1 cm(2) is fabricated. Qualitative analysis using time-of-flight secondary ion mass spectroscopy reveals the presence of impurities, including Ge and silicon, in the MCD film. Our experimental results will provide insights into the scalability of GeV fabrication using the MW PE CVD technique and effectively implement NCD-based nanoscale-sensing applications. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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| |
Language |
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Wos |
001164609600001 |
Publication Date |
2024-02-15 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
2574-0970 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
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| |
Impact Factor |
5.9 |
Times cited |
|
Open Access |
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| |
Notes |
|
Approved |
Most recent IF: 5.9; 2024 IF: NA |
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| |
Call Number |
UA @ admin @ c:irua:204826 |
Serial |
9164 |
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| Permanent link to this record |
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Author |
Wang, G.; Xie, C.; Wang, H.; Li, Q.; Xia, F.; Zeng, W.; Peng, H.; Van Tendeloo, G.; Tan, G.; Tian, J.; Wu, J. |
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Title |
Mitigated oxygen loss in lithium-rich manganese-based cathode enabled by strong Zr-O affinity |
Type |
A1 Journal article |
| |
Year |
2024 |
Publication |
Advanced functional materials |
Abbreviated Journal |
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| |
Volume |
|
Issue |
|
Pages |
2313672 |
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| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
Oxygen loss is a serious problem of lithium-rich layered oxide (LLO) cathodes, as the high capacity of LLO relies on reversible oxygen redox. Oxygen release can occur at the surface leading to the formation of spinel or rock salt structures. Also, the lattice oxygen will usually become unstable after long cycling, which remains a major roadblock in the application of LLO. Here, it is shown that Zr doping is an effective strategy to retain lattice oxygen in LLO due to the high affinity between Zr and O. A simple sol-gel method is used to dope Zr4+ into the LLOs to adjust the local electronic structure and inhibit the diffusion of oxygen anions to the surface during cycling. Compared with untreated LLOs, LLO-Zr cathodes exhibit a higher cycling stability, with 94% capacity retention after 100 cycles at 0.4 C, up to 223 mAh g-1 at 1 C, and 88% capacity retention after 300 cycles. Theoretical calculations show that due to the strong Zr-O covalent bonding, the formation energy of oxygen vacancies has effectively increased and the loss of lattice oxygen under high voltage can be suppressed. This study provides a simple method for developing high-capacity and cyclability Li-rich cathode materials for lithium-ion batteries. Oxygen release can occur at the cathode surface leading to the formation of spinel or rock salt structures. Here, it is shown that Zr doping is an effective strategy to retain lattice oxygen in lithium-rich layered oxides (LLO) due to the high affinity between Zr and O. LLO-Zr exhibit higher cycling stability, with 88% capacity retention after 300 cycles at 1 C. image |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
001159843800001 |
Publication Date |
2024-02-10 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
|
Edition |
|
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| |
ISSN |
1616-301x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
19 |
Times cited |
|
Open Access |
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| |
Notes |
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Approved |
Most recent IF: 19; 2024 IF: 12.124 |
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Call Number |
UA @ admin @ c:irua:203812 |
Serial |
9161 |
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| Permanent link to this record |
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Author |
Yorulmaz, U.; Šabani, D.; Sevik, C.; Milošević, M.V. |
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Title |
Goodenough-Kanamori-Anderson high-temperature ferromagnetism in tetragonal transition-metal xenes |
Type |
A1 Journal article |
| |
Year |
2024 |
Publication |
2D materials |
Abbreviated Journal |
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| |
Volume |
11 |
Issue |
3 |
Pages |
035013-10 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Seminal Goodenough-Kanamori-Anderson (GKA) rules provide an inceptive understanding of the superexchange interaction of two magnetic metal ions bridged with an anion, and suggest fostered ferromagnetic interaction for orthogonal bridging bonds. However, there are no examples of two-dimensional (2D) materials with structure that optimizes the GKA arguments towards enhanced ferromagnetism and its critical temperature. Here we reveal that an ideally planar GKA ferromagnetism is indeed stable in selected tetragonal transition-metal xenes (tTMXs), with Curie temperature above 300 K found in CrC and MnC. We provide the general orbitally-resolved analysis of magnetic interactions that supports the claims and sheds light at the mechanisms dominating the magnetic exchange process in these structures. Furthermore, we propose the set of three GKA-like rules that will guarantee room temperature ferromagetnism. With recent advent of epitaxially-grown tetragonal 2D materials, our findings earmark tTMXs for facilitated spintronic and magnonic applications, or as a desirable magnetic constituent of functional 2D heterostructures. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
001208053200001 |
Publication Date |
2024-04-12 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
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| |
ISSN |
2053-1583 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
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Impact Factor |
5.5 |
Times cited |
|
Open Access |
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Notes |
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Approved |
Most recent IF: 5.5; 2024 IF: 6.937 |
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Call Number |
UA @ admin @ c:irua:205464 |
Serial |
9153 |
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| Permanent link to this record |
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Author |
Xu, H.; Li, H.; Gauquelin, N.; Chen, X.; Wu, W.-F.; Zhao, Y.; Si, L.; Tian, D.; Li, L.; Gan, Y.; Qi, S.; Li, M.; Hu, F.; Sun, J.; Jannis, D.; Yu, P.; Chen, G.; Zhong, Z.; Radovic, M.; Verbeeck, J.; Chen, Y.; Shen, B. |
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Title |
Giant tunability of Rashba splitting at cation-exchanged polar oxide interfaces by selective orbital hybridization |
Type |
A1 Journal article |
| |
Year |
2024 |
Publication |
Advanced materials |
Abbreviated Journal |
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Volume |
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Issue |
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Pages |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
The 2D electron gas (2DEG) at oxide interfaces exhibits extraordinary properties, such as 2D superconductivity and ferromagnetism, coupled to strongly correlated electrons in narrow d-bands. In particular, 2DEGs in KTaO3 (KTO) with 5d t2g orbitals exhibit larger atomic spin-orbit coupling and crystal-facet-dependent superconductivity absent for 3d 2DEGs in SrTiO3 (STO). Herein, by tracing the interfacial chemistry, weak anti-localization magneto-transport behavior, and electronic structures of (001), (110), and (111) KTO 2DEGs, unambiguously cation exchange across KTO interfaces is discovered. Therefore, the origin of the 2DEGs at KTO-based interfaces is dramatically different from the electronic reconstruction observed at STO interfaces. More importantly, as the interface polarization grows with the higher order planes in the KTO case, the Rashba spin splitting becomes maximal for the superconducting (111) interfaces approximately twice that of the (001) interface. The larger Rashba spin splitting couples strongly to the asymmetric chiral texture of the orbital angular moment, and results mainly from the enhanced inter-orbital hopping of the t2g bands and more localized wave functions. This finding has profound implications for the search for topological superconductors, as well as the realization of efficient spin-charge interconversion for low-power spin-orbitronics based on (110) and (111) KTO interfaces. An unambiguous cation exchange is discovered across the interfaces of (001), (110), and (111) KTaO3 2D electron gases fabricated at room temperature. Remarkably, the (111) interfaces with the highest superconducting transition temperature also turn out to show the strongest electron-phonon interaction and the largest Rashba spin splitting. image |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
001219658400001 |
Publication Date |
2024-03-13 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
0935-9648 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
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Impact Factor |
29.4 |
Times cited |
|
Open Access |
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Notes |
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Approved |
Most recent IF: 29.4; 2024 IF: 19.791 |
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Call Number |
UA @ admin @ c:irua:206037 |
Serial |
9152 |
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| Permanent link to this record |
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Author |
Wu, X.; Ding, J.; Cui, W.; Lin, W.; Xue, Z.; Yang, Z.; Liu, J.; Nie, X.; Zhu, W.; Van Tendeloo, G.; Sang, X. |
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Title |
Enhanced electrical properties of Bi2-xSbxTe3 nanoflake thin films through interface engineering |
Type |
A1 Journal article |
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Year |
2024 |
Publication |
Energy & environment materials |
Abbreviated Journal |
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Volume |
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Issue |
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Pages |
e12755-8 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The structure-property relationship at interfaces is difficult to probe for thermoelectric materials with a complex interfacial microstructure. Designing thermoelectric materials with a simple, structurally-uniform interface provides a facile way to understand how these interfaces influence the transport properties. Here, we synthesized Bi2-xSbxTe3 (x = 0, 0.1, 0.2, 0.4) nanoflakes using a hydrothermal method, and prepared Bi2-xSbxTe3 thin films with predominantly (0001) interfaces by stacking the nanoflakes through spin coating. The influence of the annealing temperature and Sb content on the (0001) interface structure was systematically investigated at atomic scale using aberration-corrected scanning transmission electron microscopy. Annealing and Sb doping facilitate atom diffusion and migration between adjacent nanoflakes along the (0001) interface. As such it enhances interfacial connectivity and improves the electrical transport properties. Interfac reactions create new interfaces that increase the scattering and the Seebeck coefficient. Due to the simultaneous optimization of electrical conductivity and Seebeck coefficient, the maximum power factor of the Bi1.8Sb0.2Te3 nanoflake films reaches 1.72 mW m(-1) K-2, which is 43% higher than that of a pure Bi2Te3 thin film. |
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Corporate Author |
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Thesis |
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Place of Publication |
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Wos |
https://www.webofscience.com/api/gateway?GWVersion=2&SrcApp=brocade2&SrcAuth=WosAPI&KeyUT=WOS:001204 |
Publication Date |
2024-04-18 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
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ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles; WoS full record; WoS citing articles |
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Impact Factor |
|
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: NA |
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Call Number |
UA @ admin @ c:irua:205438 |
Serial |
9148 |
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| Permanent link to this record |
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Author |
Blagojević, J.; Mijin, S.D.; Bekaert, J.; Opačić, M.; Liu, Y.; Milošević, M.V.; Petrović, C.; Popović, Z.V.; Lazarević, N. |
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Title |
Competition of disorder and electron-phonon coupling in 2H-TaSe2-xSx (0≤x≤2) as evidenced by Raman spectroscopy |
Type |
A1 Journal article |
| |
Year |
2024 |
Publication |
Physical review materials |
Abbreviated Journal |
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Volume |
8 |
Issue |
2 |
Pages |
024004-24008 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
The vibrational properties of 2H-TaSe<sub>2-x</sub>S<sub>x</sub> (0≤x≤2) single crystals were probed using Raman spectroscopy and density functional theory calculations. The end members revealed two out of four symmetry-predicted Raman active modes, together with the pronounced two-phonon structure, attributable to the enhanced electron-phonon coupling. Additional peaks become observable due to crystallographic disorder for the doped samples. The evolution of the E<sub>2</sub>g<sup>2</sup> mode Fano parameter reveals that the disorder has a weak impact on electron-phonon coupling, which is also supported by the persistence of two-phonon structure in doped samples. As such, this research provides thorough insights into the lattice properties, the effects of crystallographic disorder on Raman spectra, and the interplay of this disorder with the electron-phonon coupling in 2H-TaSe<sub>2-x</sub>S<sub>x</sub> compounds. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
001171649400004 |
Publication Date |
2024-02-21 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
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| |
ISSN |
2475-9953 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
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| |
Impact Factor |
3.4 |
Times cited |
|
Open Access |
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Notes |
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Approved |
Most recent IF: 3.4; 2024 IF: NA |
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Call Number |
UA @ admin @ c:irua:204404 |
Serial |
9141 |
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| Permanent link to this record |
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Author |
Yang, C.-Q.; Yin, Z.-W.; Li, W.; Cui, W.-J.; Zhou, X.-G.; Wang, L.-D.; Zhi, R.; Xu, Y.-Y.; Tao, Z.-W.; Sang, X.; Cheng, Y.-B.; Van Tendeloo, G.; Hu, Z.-Y.; Su, B.-L. |
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Title |
Atomically deciphering the phase segregation in mixed halide perovskite |
Type |
A1 Journal article |
| |
Year |
2024 |
Publication |
Advanced functional materials |
Abbreviated Journal |
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Volume |
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Issue |
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Pages |
1-10 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Mixed-halide perovskites show promising applications in tandem solar cells owing to their adjustable bandgap. One major obstacle to their commercialization is halide phase segregation, which results in large open-circuit voltage deficiency and J-V hysteresis. However, the ambiguous interplay between structural origin and phase segregation often results in aimless and unspecific optimization strategies for the device's performance and stability. An atomic scale is directly figured out the abundant Ruddlesden-Popper anti-phase boundaries (RP-APBs) within a CsPbIBr2 polycrystalline film and revealed that phase segregation predominantly occurs at RP-APB-enriched interfaces due to the defect-mediated lattice strain. By compensating their structural lead halide, such RP-APBs are eliminated, and the decreasing of strain can be observed, resulting in the suppression of halide phase segregation. The present work provides the deciphering to precisely regulate the perovskite atomic structure for achieving photo-stable mixed halide wide-bandgap perovskites of high-efficiency tandem solar cell commercial applications. The phase segregation in mixed halide perovskite film predominantly occurs at Ruddlesden-Popper anti-phase boundaries (RP-APBs)-enriched interfaces due to the defect-mediated lattice strain. The RP-APBs defects can be eliminated by compensating for their structural lead halide deficiency, resulting in the suppression of halide phase segregation. image |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
001200673300001 |
Publication Date |
2024-04-12 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
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| |
ISSN |
1616-301x |
ISBN |
|
Additional Links |
UA library record; WoS full record |
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| |
Impact Factor |
19 |
Times cited |
|
Open Access |
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| |
Notes |
|
Approved |
Most recent IF: 19; 2024 IF: 12.124 |
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Call Number |
UA @ admin @ c:irua:205509 |
Serial |
9134 |
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| Permanent link to this record |
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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. |
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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 |
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| |
Volume |
|
Issue |
|
Pages |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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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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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
001206226700001 |
Publication Date |
2024-04-22 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
0935-9648 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
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| |
Impact Factor |
29.4 |
Times cited |
|
Open Access |
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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 |
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Call Number |
EMAT @ emat @c:irua:205967 |
Serial |
9130 |
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| Permanent link to this record |
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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. |
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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 |
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Volume |
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Issue |
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Keywords |
A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; |
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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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001227929100001 |
Publication Date |
2024-04-26 |
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ISSN |
1944-8244 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
9.5 |
Times cited |
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Open Access |
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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 |
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Call Number |
EMAT @ emat @c:irua:206322 |
Serial |
9126 |
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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. |
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Title |
Phase coexistence induced surface roughness in V2O3/Ni magnetic heterostructures |
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A1 Journal article |
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Year |
2024 |
Publication |
APL materials |
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Volume |
12 |
Issue |
4 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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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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001202661800003 |
Publication Date |
2024-04-01 |
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ISSN |
2166-532X |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
6.1 |
Times cited |
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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 |
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Call Number |
EMAT @ emat @c:irua:205569 |
Serial |
9120 |
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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. |
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Title |
Decoding Excimer Formation in Covalent–Organic Frameworks Induced by Morphology and Ring Torsion |
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A1 Journal article |
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Year |
2024 |
Publication |
Advanced materials |
Abbreviated Journal |
Advanced Materials |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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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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001206226700001 |
Publication Date |
2024-04-22 |
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Edition |
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ISSN |
0935-9648 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
29.4 |
Times cited |
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Open Access |
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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 |
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Call Number |
EMAT @ emat @c:irua:205967 |
Serial |
9118 |
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Xiao, H.; Zhang, Z.; Xu, W.; Wang, Q.; Xiao, Y.; Ding, L.; Huang, J.; Li, H.; He, B.; Peeters, F.M. |
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Title |
Terahertz optoelectronic properties of synthetic single crystal diamond |
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A1 Journal article |
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Year |
2023 |
Publication |
Diamond and related materials |
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139 |
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110266-110268 |
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A1 Journal article; Condensed Matter Theory (CMT) |
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A systematic investigation is undertaken for studying the optoelectronic properties of single crystal diamond (SCD) grown by microwave plasma chemical vapor deposition (MPCVD). It is indicated that, without intentional doping and surface treatment during the sample growth, the terahertz (THz) optical conduction in SCD is mainly affected by surface H-terminations, -OH-, O- and N-based functional groups. By using THz time-domain spectroscopy (TDS), we measure the transmittance, the complex dielectric constant and optical conductivity σ(ω) of SCD. We find that SCD does not show typical semiconductor characteristics in THz regime, where σ(ω) cannot be described rightly by the conventional Drude formula. Via fitting the real and imaginary parts of σ(ω) to the Drude-Smith formula, the ratio of the average carrier density to the effective electron mass γ = ne/m*, the electronic relaxation time τ and the electronic backscattering or localization factor can be determined optically. The temperature dependence of these parameters is examined. From the temperature dependence of γ, a metallic to semiconductor transition is observed at about T = 10 K. The temperature dependence of τ is mainly induced by electron coupling with acoustic-phonons and there is a significant effect of photon-induced electron backscattering or localization in SCD. This work demonstrates that THz TDS is a powerful technique in studying SCD which contains H-, N- and O-based bonds and has low electron density and high dc resistivity. The results obtained from this study can benefit us to gain an in-depth understanding of SCD and may provide new guidance for the application of SCD as electronic, optical and optoelectronic materials. |
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Publication Date |
2023-08-02 |
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Edition |
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ISSN |
0925-9635 |
ISBN |
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Additional Links |
UA library record |
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Impact Factor |
4.1 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 4.1; 2023 IF: 2.561 |
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Call Number |
UA @ admin @ c:irua:200920 |
Serial |
9103 |
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