Records |
Author |
Ahmadi Eshtehardi, H. |
Title |
Combined computational-experimental study on plasma and plasma catalysis for N2 fixation |
Type |
Doctoral thesis |
Year |
2024 |
Publication |
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Abbreviated Journal |
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Volume |
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Issue |
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Pages |
160 p. |
Keywords |
Doctoral thesis; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
Humanity feels the urge of shifting to a sustainable society more than at any other time in its history. Electrification of chemical industry plays a key role in this transition. The possibility of producing fertilizers from air using renewable electricity, and simultaneously, no greenhouse gas emission, resulted in an increasing interest toward plasma technology as a solution for electrification of a part of the chemical industry in the past few years. Additionally, the activation of nitrogen molecules by vibrational and electronic excitation reactions in plasma can lead to an energy-efficient process. Last but not least, the modularity (fast on/off characteristic) of plasma technology makes it capable of using intermittent renewable electricity on site for the production of fertilizers using air. All these advantages offered by plasma technology make it a potential solution for the on-site production of fertilizers in small and decentralized plants using air and renewable electricity, which leads to a considerable reduction in fertilizer production and transportation costs. However, industrialization of plasma-based NF suffers from several challenges, including challenges of plasma catalysis for the selective production of desired species, the high energy cost of plasma-based NF compared to current industrial processes, and the design and development of scaled up and energy-efficient plasma reactors for industrial purposes. In the framework of this thesis we have tried to add to the state-of-the-art (SOTA) in plasma-based NOx production and deal with its limitations using a combination of experimental and modelling work. |
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Wos |
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Publication Date |
2024-06-14 |
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Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:205246 |
Serial |
9139 |
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Author |
Yao, W.; Hui, C.; Wang, L.; Wang, J.; Gielis, J.; Shi, P. |
Title |
Comparison of the performance of two polar equations in describing the geometries of elliptical fruits |
Type |
A1 Journal article |
Year |
2024 |
Publication |
Botany letters |
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; Antwerp engineering, PhotoElectroChemistry & Sensing (A-PECS) |
Abstract |
In nature, the two-dimensional (2D) profiles of fruits from many plants often resemble ellipses. However, it remains unclear whether these profiles strictly adhere to the ellipse equation, as many natural shapes resembling ellipses are actually better described as superellipses. The superellipse equation, which includes an additional parameter n compared to the ellipse equation, can generate a broader range of shapes, with the ellipse being just a special case of the superellipse. To investigate whether the 2D profiles of fruits are better described by ellipses or superellipses, we collected a total of 751 mature and undamaged fruits from 31 naturally growing plants of Cucumis melo L. var. agrestis Naud. Our analysis revealed that most adjusted root-mean-square errors (> 92% of the 751 fruits) for fitting the superellipse equation to the fruit profiles were consistently less than 0.0165. Furthermore, there were 638 of the 751 fruits (ca. 85%) with the 95% confidence intervals of the estimated parameter n in the superellipse equation not including 2. These findings suggest that the profiles of C. melo var. agrestis fruits align more closely with the superellipse equation than with the ellipse equation. This study provides evidence for the existence of the superellipse in fruit profiles, which has significant implications for studying fruit geometries and estimating fruit volumes using the solid of revolution formula. Furthermore, this discovery may contribute to a deeper understanding of the mechanisms driving the evolution of fruit shapes. |
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Wos |
001219634500001 |
Publication Date |
2024-05-08 |
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 |
2381-8107; 2381-8115 |
ISBN |
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Additional Links |
UA library record; WoS full record |
Impact Factor |
1.5 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 1.5; 2024 IF: NA |
Call Number |
UA @ admin @ c:irua:205955 |
Serial |
9140 |
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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. |
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 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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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Wos |
001171649400004 |
Publication Date |
2024-02-21 |
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 |
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 |
Call Number |
UA @ admin @ c:irua:204404 |
Serial |
9141 |
Permanent link to this record |
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Author |
Khan, S.U.; Matshitse, R.; Borah, R.; Nemakal, M.; Moiseeva, E.O.; Dubinina, T.V.; Nyokong, T.; Verbruggen, S.W.; De Wael, K. |
Title |
Coupling of phthalocyanines with plasmonic gold nanoparticles by click chemistry for an enhanced singlet oxygen based photoelectrochemical sensing |
Type |
A1 Journal article |
Year |
2024 |
Publication |
ChemElectroChem |
Abbreviated Journal |
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Volume |
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Issue |
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Pages |
1-11 |
Keywords |
A1 Journal article; Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab); Antwerp engineering, PhotoElectroChemistry & Sensing (A-PECS) |
Abstract |
Coupling photosensitizers (PSs) with plasmonic nanoparticles increases the photocatalytic activity of PSs as the localized surface plasmon resonance (LSPR) of plasmonic nanoparticles leads to extreme concentration of light in their vicinity known as the near-field enhancement effect. To realize this in a colloidal phase, efficient conjugation of the PS molecules with the plasmonic nanoparticle surface is critical. In this work, we demonstrate the coupling of phthalocyanine (Pc) molecules with gold nanoparticles (AuNPs) in the colloidal phase via click chemistry. This conjugated Pc-AuNPs colloidal system is shown to enhance the photocatalytic singlet oxygen (1O2) production over non-conjugated Pcs and hence improve the photoelectrochemical detection of phenols. The plasmonic enhancement of the 1O2 generation by Pcs was clearly elucidated by complementary experimental and computational classical electromagnetic models. The dependence of plasmonic enhancement on the spectral position of the excitation laser wavelength and the absorbance of the Pc molecules with respect to the wavelength specific near-field enhancement is clearly demonstrated. A high similar to 8 times enhancement is obtained with green laser (532 nm) at the LSPR due to the maximum near-field enhancement at the resonance wavelength. Zinc phthalocyanine is covalently linked to plasmonic AuNPs via click chemistry to investigate the synergistic effect that boosts the overall activity toward the detection of HQ under visible light illumination. The 1O2 quantum yield of ZnPc improved significantly after conjugating with AuNPs, resulting in enhanced photoelectrochemical activity. image |
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Wos |
001214481000001 |
Publication Date |
2024-05-02 |
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 |
2196-0216 |
ISBN |
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Additional Links |
UA library record; WoS full record |
Impact Factor |
4 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 4; 2024 IF: 4.136 |
Call Number |
UA @ admin @ c:irua:205962 |
Serial |
9142 |
Permanent link to this record |
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Author |
Cioni, M.; Delle Piane, M.; Polino, D.; Rapetti, D.; Crippa, M.; Arslan Irmak, E.; Pavan, G.M.; Van Aert, S.; Bals, S. |
Title |
Data for Sampling Real‐Time Atomic Dynamics in Metal Nanoparticles by Combining Experiments, Simulations, and Machine Learning |
Type |
Dataset |
Year |
2024 |
Publication |
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Abbreviated Journal |
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Volume |
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Issue |
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Pages |
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Keywords |
Dataset; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Even at low temperatures, metal nanoparticles (NPs) possess atomic dynamics that are key for their properties but challenging to elucidate. Recent experimental advances allow obtaining atomic‐resolution snapshots of the NPs in realistic regimes, but data acquisition limitations hinder the experimental reconstruction of the atomic dynamics present within them. Molecular simulations have the advantage that these allow directly tracking the motion of atoms over time. However, these typically start from ideal/perfect NP structures and, suffering from sampling limits, provide results that are often dependent on the initial/putative structure and remain purely indicative. Here, by combining state‐of‐the‐art experimental and computational approaches, how it is possible to tackle the limitations of both approaches and resolve the atomistic dynamics present in metal NPs in realistic conditions is demonstrated. Annular dark‐field scanning transmission electron microscopy enables the acquisition of ten high‐resolution images of an Au NP at intervals of 0.6 s. These are used to reconstruct atomistic 3D models of the real NP used to run ten independent molecular dynamics simulations. Machine learning analyses of the simulation trajectories allows resolving the real‐time atomic dynamics present within the NP. This provides a robust combined experimental/computational approach to characterize the structural dynamics of metal NPs in realistic conditions. |
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Wos |
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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 |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:205843 |
Serial |
9143 |
Permanent link to this record |
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Author |
Morad, V.; Stelmakh, A.; Svyrydenko, M.; Feld, L.G.; Boehme, S.C.; Aebli, M.; Affolter, J.; Kaul, C.J.; Schrenker, N.J.; Bals, S.; Sahin, Y.; Dirin, D.N.; Cherniukh, I.; Raino, G.; Baumketner, A.; Kovalenko, M.V. |
Title |
Designer phospholipid capping ligands for soft metal halide nanocrystals |
Type |
A1 Journal article |
Year |
2024 |
Publication |
Nature |
Abbreviated Journal |
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Volume |
626 |
Issue |
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Pages |
542-548 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
The success of colloidal semiconductor nanocrystals (NCs) in science and optoelectronics is inextricable from their surfaces. The functionalization of lead halide perovskite NCs1-5 poses a formidable challenge because of their structural lability, unlike the well-established covalent ligand capping of conventional semiconductor NCs6,7. We posited that the vast and facile molecular engineering of phospholipids as zwitterionic surfactants can deliver highly customized surface chemistries for metal halide NCs. Molecular dynamics simulations implied that ligand-NC surface affinity is primarily governed by the structure of the zwitterionic head group, particularly by the geometric fitness of the anionic and cationic moieties into the surface lattice sites, as corroborated by the nuclear magnetic resonance and Fourier-transform infrared spectroscopy data. Lattice-matched primary-ammonium phospholipids enhance the structural and colloidal integrity of hybrid organic-inorganic lead halide perovskites (FAPbBr3 and MAPbBr3 (FA, formamidinium; MA, methylammonium)) and lead-free metal halide NCs. The molecular structure of the organic ligand tail governs the long-term colloidal stability and compatibility with solvents of diverse polarity, from hydrocarbons to acetone and alcohols. These NCs exhibit photoluminescence quantum yield of more than 96% in solution and solids and minimal photoluminescence intermittency at the single particle level with an average ON fraction as high as 94%, as well as bright and high-purity (about 95%) single-photon emission. Phospholipids enhance the structural and colloidal integrity of hybrid organic-inorganic lead halide perovskites and lead-free metal halide nanocrystals, which then exhibit enhanced robustness and optical properties. |
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Wos |
001176943100001 |
Publication Date |
2023-12-18 |
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 |
0028-0836; 1476-4687 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
64.8 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 64.8; 2024 IF: 40.137 |
Call Number |
UA @ admin @ c:irua:204796 |
Serial |
9144 |
Permanent link to this record |
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Author |
Pascucci, F.; Conti, S.; Perali, A.; Tempère, J.; Neilson, D. |
Title |
Effects of intralayer correlations on electron-hole double-layer superfluidity |
Type |
A1 Journal article |
Year |
2024 |
Publication |
Physical review B |
Abbreviated Journal |
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Volume |
109 |
Issue |
9 |
Pages |
094512-94515 |
Keywords |
A1 Journal article; Theory of quantum systems and complex systems; Condensed Matter Theory (CMT) |
Abstract |
We investigate the intralayer correlations acting within the layers in a superfluid system of electron -hole spatially separated layers. In this system, superfluidity is predicted to be almost exclusively confined to the Bose-Einstein condensate (BEC) and crossover regimes where the electron -hole pairs are well localized. In this case, Hartree-Fock is an excellent approximation for the intralayer correlations. We find in the BEC regime that the effect of the intralayer correlations on superfluid properties is negligible but in the BCS-BEC crossover regime the superfluid gap is significantly weakened by the intralayer correlations. This is caused by the intralayer correlations boosting the number of low -energy particle -hole excitations that drive the screening. We further find that the intralayer correlations suppress the predicted phenomenon in which the average pair size passes through a minimum as the crossover regime is traversed. |
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Wos |
001199662600001 |
Publication Date |
2024-03-18 |
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 |
2469-9969; 2469-9950 |
ISBN |
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Additional Links |
UA library record; WoS full record |
Impact Factor |
3.7 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 3.7; 2024 IF: 3.836 |
Call Number |
UA @ admin @ c:irua:205476 |
Serial |
9145 |
Permanent link to this record |
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Author |
Manaigo, F.; Bahnamiri, O.S.; Chatterjee, A.; Panepinto, A.; Krumpmann, A.; Michiels, M.; Bogaerts, A.; Snyders, R. |
Title |
Electrical stability and performance of a nitrogen-oxygen atmospheric pressure gliding arc plasma |
Type |
A1 Journal article |
Year |
2024 |
Publication |
ACS Sustainable Chemistry and Engineering |
Abbreviated Journal |
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Volume |
12 |
Issue |
13 |
Pages |
5211-5219 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
Nonthermal plasmas are currently being studied as a green alternative to the Haber-Bosch process, which is, today, the dominant industrial process allowing for the fixation of nitrogen and, as such, a fundamental component for the production of nitrogen-based industrial fertilizers. In this context, the gliding arc plasma (GAP) is considered a promising choice among nonthermal plasma options. However, its stability is still a key parameter to ensure industrial transfer of the technology. Nowadays, the conventional approach to stabilize this plasma process is to use external resistors. Although this indeed allows for an enhancement of the plasma stability, very little is reported about how it impacts the process efficiency, both in terms of NOx yield and energy cost. In this work, this question is specifically addressed by studying a DC-powered GAP utilized for nitrogen fixation into NOx at atmospheric pressure stabilized by variable external resistors. Both the performance and the stability of the plasma are reported as a function of the utilization of the resistors. The results confirm that while the use of a resistor indeed allows for a strong stabilization of the plasma without impacting the NOx yield, especially at high plasma current, it dramatically impacts the energy cost of the process, which increases from 2.82 to 7.9 MJ/mol. As an alternative approach, we demonstrate that the replacement of the resistor by an inductor is promising since it allows for decent stabilization of the plasma, while it does not affect either the energy cost of the process or the NOx yield. |
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Wos |
001186347900001 |
Publication Date |
2024-03-16 |
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 |
2168-0485 |
ISBN |
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Additional Links |
UA library record; WoS full record |
Impact Factor |
8.4 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 8.4; 2024 IF: 5.951 |
Call Number |
UA @ admin @ c:irua:204774 |
Serial |
9146 |
Permanent link to this record |
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Author |
De Luca, F.; Abate, S.; Bogaerts, A.; Centi, G. |
Title |
Electrified CO2 conversion : integrating experimental, computational, and process simulation methods for sustainable chemical synthesis |
Type |
Doctoral thesis |
Year |
2024 |
Publication |
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Abbreviated Journal |
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Volume |
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Issue |
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Pages |
xv, 152 p. |
Keywords |
Doctoral thesis; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
Nowadays, the burning of fossil fuels, particularly petroleum, natural gas, and coal, meets the rising need for power and fuels for automobiles and industries. This has given rise to ecological and climate challenges. This thesis explores these issues from three distinct perspectives: (i) experimental, (ii) computational, and (iii) process simulation, with a focus on studying CO2 as an alternative and economically viable raw material. Firstly, the experimental study is focused on the synthesis, characterization, and testing of novel catalysts for electroreduction of CO2 and oxalic acid, an intermediate product of CO2. Electrocatalysts based on Cu supported by citrus (orange and lemon) peel biomass are prepared. These catalysts exhibit activity in the electrochemical reduction of CO2, emphasizing the effectiveness of biomasses, particularly orange peels, as environmentally friendly precursors for sustainable and efficient electrocatalysts. In addition, graphitic carbon nitrides/TiO2 nanotubes (g-C3N4/TiNT) composites are prepared for the electrocatalytic reduction of oxalic acid to glycolic acid, revealing superior electrocatalytic properties compared to pristine TiNT. Characterization by X-ray diffraction, X-ray photoelectron spectroscopy, and scanning electronic microscopy were performed for all the prepared electrocatalysts. Delving into the reduction of CO2 on Cu catalysts, a computational study about the synthesis of methanol on Cu(111) surface is performed by using the Vienna Ab initio Simulation Package. A systematic study is carried out to define the activation energies of the elementary reactions by using mGGA DF. Consequently, it is shown that the rate-controlling step is CH3O* hydrogenation and the formate pathway on Cu(111) proceeds through the HCOOH* intermediate. Finally, the process simulation, performed by using the software Aspen Plus 11 from AspenTech Inc., is based on the comparison of a catalytic (oxidation of ethylene glycol) and an electrocatalytic process (CO2 electroreduction chain) to synthesize glycolic acid. An economic analysis of the operational and investment costs reveals that the catalytic process is more cost-effective due to the current instability of electrocatalysts and proton exchange membranes, resulting in increased maintenance costs and, consequently, higher prices for the product. |
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Additional Links |
UA library record |
Impact Factor |
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Times cited |
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Open Access |
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Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:205262 |
Serial |
9147 |
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. |
Title |
Enhanced electrical properties of Bi2-xSbxTe3 nanoflake thin films through interface engineering |
Type |
A1 Journal article |
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 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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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Wos |
001204495900001 |
Publication Date |
2024-04-18 |
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Series Title |
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Abbreviated Series Title |
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Series Issue |
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Edition |
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ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:205438 |
Serial |
9148 |
Permanent link to this record |
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Author |
Vlasov, E. |
Title |
Exploiting secondary electrons in transmission electron microscopy for 3D characterization of nanoparticle morphologies |
Type |
Doctoral thesis |
Year |
2024 |
Publication |
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Abbreviated Journal |
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Volume |
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Issue |
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Pages |
x, 118 p. |
Keywords |
Doctoral thesis; Electron microscopy for materials research (EMAT) |
Abstract |
Electron tomography (ET) is an indispensable tool for determining the three-dimensional (3D) structure of nanomaterials in (scanning) transmission electron microscopy ((S)TEM). ET enables 3D characterization of a variety of nanomaterials across different fields, including life sciences, chemistry, solid-state physics, and materials science down to atomic resolution. However, the acquisition of a conventional tilt series for ET is a time-consuming process and thus cannot capture fast transformations of materials in realistic conditions. Moreover, only a limited number of nanoparticles (NPs) can be investigated, hampering a general understanding of the average properties of the material. Therefore, alternative characterization techniques that allow for high-resolution characterization of the surface structure without the need to acquire a full tilt series in ET are required which would enable a more time-efficient investigation with better statistical value. In the first part of this work, an alternative technique for the characterization of the morphology of NPs to improve the throughput and temporal resolution of ET is presented. The proposed technique exploits surface-sensitive secondary electron (SE) imaging in STEM employed using a modification of electron beam-induced current (EBIC) setup. The time- and dose efficiency of SEEBIC are tested in comparison with ET and superior spatial resolution is shown compared to conventional scanning electron microscopy. Finally, contrast artefacts arising in SEEBIC images are described, and their origin is discussed. The second part of my thesis focuses on real applications of the proposed technique and introduces a high-throughput methodology that combines images acquired by SEEBIC with quantitative image analysis to retrieve information about the helicity of gold nanorods. It shows that SEEBIC imaging overcomes the limitation of ET providing a general understanding of the connection between structure and chiroptical properties. |
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Wos |
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Publication Date |
2024-06-17 |
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UA library record |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:204905 |
Serial |
9149 |
Permanent link to this record |
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Author |
Ozdemir, I.; Arkin, H.; Milošević, M.V.; V. Barth, J.; Aktuerk, E. |
Title |
Exploring the adsorption mechanisms of neurotransmitter and amino acid on Ti3C2-MXene monolayer : insights from DFT calculations |
Type |
A1 Journal article |
Year |
2024 |
Publication |
Surfaces and interfaces |
Abbreviated Journal |
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Volume |
46 |
Issue |
|
Pages |
104169-9 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
In this study, we conducted a systematic density functional theory (DFT) investigation of the interaction between Ti3C2-MXene monolayer and biological molecules dopamine (DA) and serine (Ser) as neurotransmitter and amino acid, respectively. Our calculations show good agreement with previous literature findings for the optimized Ti3C2 monolayer. We found that DA and Ser molecules bind to the Ti3C2 surface with adsorption energies of -2.244 eV and -3.960 eV, respectively. The adsorption of Ser resulted in the dissociation of one H atom. Electronic density of states analyses revealed little changes in the electronic properties of the Ti3C2-MXene monolayer upon adsorption of the biomolecules. We further investigated the interaction of DA and Ser with Ti3C2 monolayers featuring surface -termination with OH functional group, and Ti -vacancy. Our calculations indicate that the adsorption energies significantly decrease in the presence of surface termination, with adsorption energies of -0.097 eV and -0.330 eV for DA and Ser, respectively. Adsorption energies on the Ti -vacancy surface, on the other hand, are calculated to be -3.584 eV and -3.856 eV for DA and Ser, respectively. Our results provide insights into the adsorption behavior of biological molecules on Ti3C2-MXene, demonstrating the potential of this material for biosensing and other biomedical applications. These findings highlight the importance of surface modifications in the development of functional materials and devices based on Ti3C2-MXene, and pave the way for future investigations into the use of 2D materials for biomedical applications. |
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Wos |
001206950300001 |
Publication Date |
2024-03-08 |
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 |
2468-0230 |
ISBN |
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Additional Links |
UA library record; WoS full record |
Impact Factor |
6.2 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 6.2; 2024 IF: NA |
Call Number |
UA @ admin @ c:irua:205977 |
Serial |
9150 |
Permanent link to this record |
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Author |
Shafiei, M.; Fazileh, F.; Peeters, F.M.; Milošević, M.V. |
Title |
Floquet engineering of axion and high-Chern number phases in a topological insulator under illumination |
Type |
A1 Journal article |
Year |
2024 |
Publication |
SciPost Physics Core |
Abbreviated Journal |
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Volume |
7 |
Issue |
7 |
Pages |
024-16 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Quantum anomalous Hall, high-Chern number, and axion phases in topological insulators are characterized by its Chern invariant C (respectively, C = 1, integer C > 1, and C = 0 with half-quantized Hall conductance of opposite signs on top and bottom surfaces). They are of recent interest because of novel fundamental physics and prospective applications, but identifying and controlling these phases has been challenging in practice. Here we show that these states can be created and switched between in thin films of Bi2Se3 by Floquet engineering, using irradiation by circularly polarized light. We present the calculated phase diagrams of encountered topological phases in Bi2Se3, as a function of wavelength and amplitude of light, as well as sample thickness, after properly taking into account the penetration depth of light and the variation of the gap in the surface states. These findings open pathways towards energy-efficient optoelectronics, advanced sensing, quantum information processing and metrology. |
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Wos |
001217885300001 |
Publication Date |
2024-05-01 |
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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 |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:205972 |
Serial |
9151 |
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. |
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) |
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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Wos |
001219658400001 |
Publication Date |
2024-03-13 |
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 |
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Additional Links |
UA library record; WoS full record |
Impact Factor |
29.4 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 29.4; 2024 IF: 19.791 |
Call Number |
UA @ admin @ c:irua:206037 |
Serial |
9152 |
Permanent link to this record |
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Author |
Yorulmaz, U.; Šabani, D.; Sevik, C.; Milošević, M.V. |
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 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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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Wos |
001208053200001 |
Publication Date |
2024-04-12 |
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 |
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Additional Links |
UA library record; WoS full record |
Impact Factor |
5.5 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 5.5; 2024 IF: 6.937 |
Call Number |
UA @ admin @ c:irua:205464 |
Serial |
9153 |
Permanent link to this record |
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Author |
Bampouli, A.; Goris, Q.; Hussain, M.N.; Louisnard, O.; Stefanidis, G.D.; Van Gerven, T. |
Title |
Importance of design and operating parameters in a sonication system for viscous solutions : effects of input power, horn tip diameter and reactor capacity |
Type |
A1 Journal article |
Year |
2024 |
Publication |
Chemical engineering and processing |
Abbreviated Journal |
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Volume |
198 |
Issue |
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Pages |
109715-12 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
This study investigates the distribution of ultrasound (US) energy in a batch system for solutions with viscosity ranging from 1 to approximately 3000 mPas. Sonication was performed using horn type configurations operating at 20-30 kHz and rated power capacity of 50 or 200 W. Two different tip diameters (3 or 7 mm) and two insertion depths (35 or 25 mm) within vessels of different sizes ( approximate to 60 or 130 ml) were utilized. Additionally, a special conical tip design was employed. For each experimental setup, the calorimetric efficiency was estimated, the cavitationally active regions were visualized using the sonochemiluminescence (SCL) method and bubble cluster formation inside the vessel was macroscopically observed using a high speed camera (HSC). In the viscosity range tested, the calorimetry results showed that the efficiency and continuous operation of the device depend on both the rated power and the horn tip diameter. The ratio between electrical and calorimetric power input remained consistently around 40 to 50% across the different configurations for water, but for the 123.2 mPas solution exhibited significant variation ranging from 40 to 85%. Moreover, the power density in the smaller reactor was found to be nearly double compared to the larger one. The SCL analysis showed multiple cavitationally active zones in all setups, and the zones intensity decreased considerably with increase of the solutions viscosity. The results for the cone tip were not conclusive, but can be used as the basis for further investigation. The current research highlights the importance of thoroughly understanding the impact of each design parameter, and of establishing characterization methodologies to assist in the future development of scaled-up, commercial applications. |
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Wos |
001218630800001 |
Publication Date |
2024-02-21 |
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 |
0255-2701 |
ISBN |
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Additional Links |
UA library record; WoS full record |
Impact Factor |
4.3 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 4.3; 2024 IF: 2.234 |
Call Number |
UA @ admin @ c:irua:206003 |
Serial |
9154 |
Permanent link to this record |
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Author |
Tsonev, I.; Ahmadi Eshtehardi, H.; Delplancke, M.-P.; Bogaerts, A. |
Title |
Importance of geometric effects in scaling up energy-efficient plasma-based nitrogen fixation |
Type |
A1 Journal article |
Year |
2024 |
Publication |
Sustainable energy & fuels |
Abbreviated Journal |
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Volume |
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Issue |
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Pages |
1-19 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
Despite the recent promising potential of plasma-based nitrogen fixation, the technology faces significant challenges in efficient upscaling. To tackle this challenge, we investigate two reactors, i.e., a small one, operating in a flow rate range of 5-20 ln min-1 and current range of 200-500 mA, and a larger one, operating at higher flow rate (100-300 ln min-1) and current (400-1000 mA). Both reactors operate in a pin-to-pin configuration and are powered by direct current (DC) from the same power supply unit, to allow easy comparison and evaluate the effect of upscaling. In the small reactor, we achieve the lowest energy cost (EC) of 2.8 MJ mol-1, for a NOx concentration of 1.72%, at a flow rate of 20 ln min-1, yielding a production rate (PR) of 33 g h-1. These values are obtained in air; in oxygen-enriched air, the results are typically better, at the cost of producing oxygen-enriched air. In the large reactor, the higher flow rates reduce the NOx concentration due to lower SEI, while maintaining a similar EC. This stresses the important effect of the geometrical configuration of the arc, which is typically concentrated in the center of the reactor, resulting in limited coverage of the reacting gas flow, and this is identified as the limiting factor for upscaling. However, our experiments reveal that by changing the reactor configuration, and thus the plasma geometry and power deposition mechanisms, the amount of gas treated by the plasma can be enhanced, leading to successful upscaling. To obtain more insights in our experiments, we performed thermodynamic equilibrium calculations. First of all, they show that our measured lowest EC closely aligns with the calculated minimum thermodynamic equilibrium at atmospheric pressure. In addition, they reveal that the limited NOx production in the large reactor results from the contracted nature of the plasma. To solve this limitation, we let the large reactor operate in so-called torch configuration. Indeed, the latter enhances the NOx concentrations compared to the pin-to-pin configuration, yielding a PR of 80 g h-1 at an EC of 2.9 MJ mol-1 and NOx concentration of 0.31%. This illustrates the importance of reactor design in upscaling. With the focus on feasibility evaluation of scaling-up plasma-based nitrogen fixation by combined experiments and thermodynamic modelling, we aim to tackle the challenge of design and development of an energy-efficient and scaled-up plasma reactor. |
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Place of Publication |
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Wos |
001203657700001 |
Publication Date |
2024-04-11 |
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 |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:205435 |
Serial |
9155 |
Permanent link to this record |
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Author |
Leigh, S.; Doyle, S.J.; Smith, G.J.; Gibson, A.R.; Boswell, R.W.; Charles, C.; Dedrick, J.P. |
Title |
Ionization and neutral gas heating efficiency in radio frequency electrothermal microthrusters : the role of driving frequency |
Type |
A1 Journal article |
Year |
2024 |
Publication |
Physics of plasmas |
Abbreviated Journal |
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Volume |
31 |
Issue |
2 |
Pages |
023509-23513 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
The development of compact, low power, charge-neutral propulsion sources is of significant recent interest due to the rising application of micro-scale satellite platforms. Among such sources, radio frequency (rf) electrothermal microthrusters present an attractive option due to their scalability, reliability, and tunable control of power coupling to the propellant. For micropropulsion applications, where available power is limited, it is of particular importance to understand how electrical power can be transferred to the propellant efficiently, a process that is underpinned by the plasma sheath dynamics. In this work, two-dimensional fluid/Monte Carlo simulations are employed to investigate the effects of applied voltage frequency on the electron, ion, and neutral heating in an rf capacitively coupled plasma microthruster operating in argon. Variations in the electron and argon ion densities and power deposition, and their consequent effect on neutral-gas heating, are investigated with relation to the phase-averaged and phase-resolved sheath dynamics for rf voltage frequencies of 6-108 MHz at 450 V. Driving voltage frequencies above 40.68 MHz exhibit enhanced volumetric ionization from bulk electrons at the expense of the ion heating efficiency. Lower driving voltage frequencies below 13.56 MHz exhibit more efficient ionization due to secondary electrons and an increasing fraction of rf power deposition into ions. Thermal efficiencies are improved by a factor of 2.5 at 6 MHz as compared to the more traditional 13.56 MHz, indicating a favorable operating regime for low power satellite applications. |
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Wos |
001207449000001 |
Publication Date |
2024-02-23 |
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 |
1070-664x |
ISBN |
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Additional Links |
UA library record; WoS full record |
Impact Factor |
2.2 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 2.2; 2024 IF: 2.115 |
Call Number |
UA @ admin @ c:irua:205506 |
Serial |
9156 |
Permanent link to this record |
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Author |
Vermeulen, B.B.; Monteiro, M.G.; Giuliano, D.; Sorée, B.; Couet, S.; Temst, K.; Nguyen, V.D. |
Title |
Magnetization-switching dynamics driven by chiral coupling |
Type |
A1 Journal article |
Year |
2024 |
Publication |
Physical review applied |
Abbreviated Journal |
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Volume |
21 |
Issue |
2 |
Pages |
024050-11 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The Dzyaloshinskii-Moriya interaction (DMI) is known to play a central role in stabilizing chiral spin textures such as skyrmions and domain walls (DWs). Electrical manipulation of DW and skyrmion motion offers possibilities for next-generation, scalable and energy-efficient spintronic devices. However, achieving the full potential of these nanoscale devices requires overcoming several challenges, including reliable electrical write and read techniques for these magnetic objects, and addressing pinning and Joule-heating concerns. Here, through micromagnetic simulations and analytical modeling, we show that DMI can directly induce magnetization switching of a nanomagnet with perpendicular magnetic anisotropy (PMA). We find that the switching is driven by the interplay between the DMI-induced magnetic frustration and the PMA. By introducing magnetic tunnel junctions to electrically access and control the magnetization direction of the PMA nanomagnet, we first show the potential of this concept to enable high-density fieldfree spin-orbit torque magnetic random-access memory. Ultimately, we demonstrate that it offers a way of transferring and processing spin information for logic operation without relying on current-driven DW or skyrmion motion. |
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Wos |
001187487900001 |
Publication Date |
2024-02-26 |
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 |
2331-7019 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.6 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 4.6; 2024 IF: 4.808 |
Call Number |
UA @ admin @ c:irua:205518 |
Serial |
9157 |
Permanent link to this record |
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Author |
Moura, V.N.; Chaves, A.; Peeters, F.M.; Milošević, M.V. |
Title |
McMillan-Ginzburg-Landau theory of singularities and discommensurations in charge density wave states of transition metal dichalcogenides |
Type |
A1 Journal article |
Year |
2024 |
Publication |
Physical review B |
Abbreviated Journal |
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Volume |
109 |
Issue |
9 |
Pages |
094507-94511 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The McMillan-Ginzburg-Landau (MGL) model for charge density waves (CDW) is employed in a systematic phenomenological study of the different phases that have been probed in recent experiments involving transition metal dichalcogenides. We implemented an efficient imaginary time evolution method to solve the MGL equations, which enabled us to investigate the role of different coupling parameters on the CDW patterns and to perform calculations with different energy functionals that lead to several experimentally observed singularities in the CDW phase profiles. In particular, by choosing the appropriate energy functionals, we were able to obtain phases that go beyond the well-known periodic phase slips (discommensurations), exhibiting also topological defects (i.e., vortex-antivortex pairs), domain walls where the CDW order parameter is suppressed, and even CDW with broken rotational symmetry. Finally, we briefly discuss the effect of these different CDW phases on the profile and critical temperature of the competing superconducting state. |
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Wos |
001199651500001 |
Publication Date |
2024-03-11 |
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 |
|
ISSN |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
Impact Factor |
3.7 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 3.7; 2024 IF: 3.836 |
Call Number |
UA @ admin @ c:irua:205491 |
Serial |
9158 |
Permanent link to this record |
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Author |
Iungin, O.; Shydlovska, O.; Moshynets, O.; Vasylenko, V.; Sidorenko, M.; Mickevicius, S.; Potters, G. |
Title |
Metal-based nanoparticles : an alternative treatment for biofilm infection in hard-to-heal wounds |
Type |
A1 Journal article |
Year |
2024 |
Publication |
Journal of wound care |
Abbreviated Journal |
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Volume |
33 |
Issue |
s:[4A] |
Pages |
99-110 |
Keywords |
A1 Journal article; Antwerp engineering, PhotoElectroChemistry & Sensing (A-PECS) |
Abstract |
Metal-based nanoparticles (MNPs) are promoted as effective compounds in the treatment of bacterial infections and as possible alternatives to antibiotics. These MNPs are known to affect a broad spectrum of microorganisms using a multitude of strategies, including the induction of reactive oxygen species and interaction with the inner structures of the bacterial cells. The aim of this review was to summarise the latest studies about the effect of metal-based nanoparticles on pathogenic bacterial biofilm formed in wounds, using the examples of Gram-positive bacterium Staphylococcus aureus and Gram-negative bacterium Pseudomonas aeruginosa, as well as provide an overview of possible clinical applications. Declaration of interest: The authors have no conflicts of interest. |
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Place of Publication |
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Wos |
001208810700003 |
Publication Date |
2024-04-08 |
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 |
0969-0700 |
ISBN |
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Additional Links |
UA library record; WoS full record |
Impact Factor |
1.9 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 1.9; 2024 IF: 1.446 |
Call Number |
UA @ admin @ c:irua:205959 |
Serial |
9159 |
Permanent link to this record |
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Author |
Kummamuru, N.B. |
Title |
Methane and hydrogen storage in clathrate hydrates |
Type |
Doctoral thesis |
Year |
2024 |
Publication |
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Abbreviated Journal |
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Volume |
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Issue |
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Pages |
XXV, 260 p. |
Keywords |
Doctoral thesis; Engineering sciences. Technology; Antwerp engineering, PhotoElectroChemistry & Sensing (A-PECS) |
Abstract |
In a world increasingly reliant on alternative energy sources, the quest for efficient and secure storage solutions is paramount. This doctoral thesis explores the exciting potential of a familiar material – water – to act as a vault for next-generation energy sources like hydrogen (H2) and methane (CH4). Nature offers a solution in the form of clathrate hydrates, fascinating cage-like structures formed from water molecules that can trap these gas molecules within their framework. This research investigates on improving the formation kinetics and gas storage capabilities of clathrate hydrates utilizing porous materials and the interstitial space between non-porous materials to augment the contact between gas and water thereby catalysing the growth of hydrates and unlocking their full potential as efficient and secure energy storage reservoirs. A key outcome of this research is the formulation of an empirical correlation, offering predictive insights into CH4 hydrate phase equilibrium conditions. Innovative approaches utilizing thermally conductive beads have yielded substantial enhancements in CH4 uptake. Furthermore, the identification of optimal water content within porous materials showcases a pathway to maximize CH4 storage capacity and hydrate growth kinetics. In the domain of hydrogen storage, attention is also directed towards unstirred systems, where the integration of functionalized porous materials has demonstrated a significant improvement in the rate of hydrate formation and the overall H2 storage capacity. A noteworthy achievement of this research lies in the successful storage of H2 within confined CH4 hydrates through a gas exchange process and the preliminary results show the potential for safer and more sustainable method for H2 storage at mild thermodynamic conditions, offering promising prospects for future energy systems. |
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Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:206258 |
Serial |
9160 |
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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. |
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 |
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Issue |
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Pages |
2313672 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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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001159843800001 |
Publication Date |
2024-02-10 |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1616-301x |
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Additional Links |
UA library record; WoS full record |
Impact Factor |
19 |
Times cited |
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Open Access |
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Approved |
Most recent IF: 19; 2024 IF: 12.124 |
Call Number |
UA @ admin @ c:irua:203812 |
Serial |
9161 |
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Author |
Zhou, S.; Zhang, C.; Xu, W.; Zhang, J.; Xiao, Y.; Ding, L.; Wen, H.; Cheng, X.; Hu, C.; Li, H.; Li, X.; Peeters, F.M. |
Title |
Observation of temperature induced phase transitions in TiO superconducting thin film via infrared measurement |
Type |
A1 Journal article |
Year |
2024 |
Publication |
Infrared physics and technology |
Abbreviated Journal |
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Volume |
137 |
Issue |
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Pages |
105160-105169 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
In contrast to conventional polycrystalline titanium oxide (TiO), it was found recently that the superconducting transition temperature Tc can be significantly enhanced from about 2 K to 7.4 K in cubic TiO thin films grown epitaxially on alpha-Al2O3 substrates. This kind of TiO film is also expected to have distinctive optoelectronic properties, which are still not very clear up to now. Herein, by using infrared (IR) reflection measurement we investigate the temperature-dependent optoelectronic response of a cubic TiO thin film, in which temperature induced phase transitions are observed. The semiconductor-, metallic- and semiconductor-like electronic phases of this superconducting film are found in the temperature regimes from 10 to 110 K, 110 to 220 K and above 220 K, respectively. The results obtained optically are consistent with those measured by transport experiment. Furthermore, based on an improved reflection model developed here, we extract the complex optical conductivity of the cubic TiO thin film. We are able to approximately determine the characteristic parameters (e.g., effective electron mass, carrier density, scattering time, etc.) for different electronic phases by fitting the optical conductivity with the modified Lorentz formula. These results not only deepen our understanding of the fundamental physics for cubic TiO thin films but also may find applications in optoelectronic devices based on superconductors. |
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001170490200001 |
Publication Date |
2024-01-21 |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1350-4495 |
ISBN |
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Additional Links |
UA library record; WoS full record |
Impact Factor |
3.3 |
Times cited |
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Open Access |
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Approved |
Most recent IF: 3.3; 2024 IF: 1.713 |
Call Number |
UA @ admin @ c:irua:204853 |
Serial |
9162 |
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Author |
Coulombier, M.; Baral, P.; Orekhov, A.; Dohmen, R.; Raskin, J.P.; Pardoen, T.; Cordier, P.; Idrissi, H. |
Title |
On-chip very low strain rate rheology of amorphous olivine films |
Type |
A1 Journal article |
Year |
2024 |
Publication |
Acta materialia |
Abbreviated Journal |
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Volume |
266 |
Issue |
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Pages |
119693-12 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Recent observations made by the authors revealed the activation of stress induced amorphization and sliding at grain boundary in olivine [1], a mechanism which is expected to play a pivotal role in the viscosity drop at the lithosphere-asthenosphere boundary and the brittle -ductile transition in the lithospheric mantle. However, there is a lack of information in the literature regarding the intrinsic mechanical properties and the elementary deformation mechanisms of this material, especially at time scales relevant for geodynamics. In the present work, amorphous olivine films were obtained by pulsed laser deposition (PLD). The mechanical response including the rate dependent behavior are investigated using a tension -on -chip (TOC) method developed at UCLouvain allowing to perform creep/relaxation tests on thin films at extremely low strain rates. In the present work, strain rate down to 10-12 s- 1 was reached which is unique. High strain rate sensitivity of 0.054 is observed together with the activation of relaxation at the very early stage of deformation. Furthermore, digital image correlation (DIC), used for the first time on films deformed by TOC, reveals local strain heterogeneities. The relationship between such heterogeneities, the high strain rate sensitivity and the effect of the electron beam in the scanning electron microscope is discussed and compared to the literature. |
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001170513400001 |
Publication Date |
2024-01-17 |
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Edition |
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ISSN |
1359-6454 |
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Additional Links |
UA library record; WoS full record |
Impact Factor |
9.4 |
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Approved |
Most recent IF: 9.4; 2024 IF: 5.301 |
Call Number |
UA @ admin @ c:irua:204864 |
Serial |
9163 |
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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. |
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 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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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001164609600001 |
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2024-02-15 |
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Edition |
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2574-0970 |
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UA library record; WoS full record |
Impact Factor |
5.9 |
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Most recent IF: 5.9; 2024 IF: NA |
Call Number |
UA @ admin @ c:irua:204826 |
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9164 |
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Author |
Fang, W.; Wang, X.; Li, S.; Hao, Y.; Yang, Y.; Zhao, W.; Liu, R.; Li, D.; Li, C.; Gao, X.; Wang, L.; Guo, H.; Yi, Y. |
Title |
Plasma-catalytic one-step steam reforming of CH₄ to CH₃OH and H₂ promoted by oligomerized [Cu-O-Cu] species on zeolites |
Type |
A1 Journal article |
Year |
2024 |
Publication |
Green chemistry : cutting-edge research for a greener sustainable future |
Abbreviated Journal |
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Volume |
26 |
Issue |
9 |
Pages |
5150-5154 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
Oligomerized [Cu-O-Cu] species are reported to be efficient in promoting plasma catalytic one-step steam reforming of methane to methanol and hydrogen, achieving 6.8% CH4 conversion and 73.1% CH3OH selectivity without CO2. |
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001195192800001 |
Publication Date |
2024-04-02 |
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Edition |
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1463-9262; 1463-9270 |
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Additional Links |
UA library record; WoS full record |
Impact Factor |
9.8 |
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Approved |
Most recent IF: 9.8; 2024 IF: 9.125 |
Call Number |
UA @ admin @ c:irua:205514 |
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9165 |
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Long, Y.; Wang, X.; Zhang, H.; Wang, K.; Ong, W.-L.; Bogaerts, A.; Li, K.; Lu, C.; Li, X.; Yan, J.; Tu, X.; Zhang, H. |
Title |
Plasma chemical looping : unlocking high-efficiency CO₂ conversion to clean CO at mild temperatures |
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A1 Journal article |
Year |
2024 |
Publication |
JACS Au |
Abbreviated Journal |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
We propose a plasma chemical looping CO2 splitting (PCLCS) approach that enables highly efficient CO2 conversion into O-2-free CO at mild temperatures. PCLCS achieves an impressive 84% CO2 conversion and a 1.3 mmol g(-1) CO yield, with no O-2 detected. Crucially, this strategy significantly lowers the temperature required for conventional chemical looping processes from 650 to 1000 degrees C to only 320 degrees C, demonstrating a robust synergy between plasma and the Ce0.7Zr0.3O2 oxygen carrier (OC). Systematic experiments and density functional theory (DFT) calculations unveil the pivotal role of plasma in activating and partially decomposing CO2, yielding a mixture of CO, O-2/O, and electronically/vibrationally excited CO2*. Notably, these excited CO2* species then efficiently decompose over the oxygen vacancies of the OCs, with a substantially reduced activation barrier (0.86 eV) compared to ground-state CO2 (1.63 eV), contributing to the synergy. This work offers a promising and energy-efficient pathway for producing O-2-free CO from inert CO2 through the tailored interplay of plasma and OCs. |
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001225139200001 |
Publication Date |
2024-05-08 |
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UA library record; WoS full record |
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Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:205970 |
Serial |
9166 |
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Author |
Lu, Q. |
Title |
Precipitation behavior and heat resistance properties of Al-Cu-Mg-Ag-(Si) alloy |
Type |
Doctoral thesis |
Year |
2024 |
Publication |
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Abbreviated Journal |
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Volume |
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Issue |
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Pages |
VIII, 212 p. |
Keywords |
Doctoral thesis; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
With the rapid increase in the speed of new-generation aerospace vehicles, conventional heat-resistant aluminum alloys cannot meet the long-term service of the equipment. Therefore, the development of new high-strength heat-resistant aluminum alloys is of great strategic for the sustainable and high-quality development of industries. Al-Cu-Mg-Ag alloy is an age-hardenable heat-resistant aluminum alloy and has high strength and heat resistance. The addition of alloying elements such as Si and Sc to Al-Cu-Mg-Ag alloy introduces a competitive relationship among the σ-Al5Cu6Mg2, θ′-Al2Cu, and Ω phases. Therefore, a systematic investigation of precipitation behavior and heat resistance of Al-Cu-Mg-Ag-(Si) is essential for guiding the design of high-strength heat-resistant aluminum alloys. Combined characterization testing methods such as scanning electron microscopy, transmission electron microscopy, atom probe tomography, microhardness testing, and tensile testing with simulation calculation methods such as calculation of phase diagram, first-principles calculations, and Ab initio molecular dynamics, the effects of heat treatment processes and element content on the precipitation behavior, mechanical properties, and heat resistance of Al-Cu-Mg-Ag-(Si) alloys were systematically investigated. Furthermore, a multiple interface segregation structure was constructed at the θ′/Al interface, and a new Al-Cu-Mg-Ag-Si-Sc alloy with synergistically improved strength and heat resistance was developed. The main conclusions are as follows: (1) Based on the Kampmann-Wagner-Numerical theory, the relationship between the coarsening rate of the Ω phase and the aging process was analyzed, revealing for the first time that the critical size of Ω phase ( ) under thermal exposure temperature was the key factor determining the coarsening rate of Ω phase during long time thermal exposure heat treatment. After artificial ageing, when the size of Ω phase was smaller than the critical size , the dissolution of smaller Ω phase leaded to a rapid decrease in the number density of Ω phases, thereby reducing the heat resistance of the alloy. When the size of Ω phase was greater than or equal to the critical size , the coarsening rate of Ω phase was consistent, but a larger initial size would result in a larger final size after long-term thermal exposure. Therefore, the closer the size of Ω phase in the alloy is to the critical size under heat exposure temperature, the better the heat resistance of the alloy. (2) A concept of constructing a multiple interface segregation structure at the precipitate/matrix interface was proposed, and based on this concept, a multiple interface segregation structure containing the C/L-AlMgSiCu interfacial phase, newly discovered χ-AgMg interfacial phase, and Sc segregation layer was successfully constructed at the θ′/Al interface. The existence of the multiple interface segregation structure ensured that the designed Al-Cu-Mg-Ag-Si-Sc alloy maintains a yield strength of 400 MPa after thermal exposure at 200 C for 100 h, with a strength retention rate of 97%, creating a new record for the synergistic improvement of strength and heat resistance in aluminum alloys. In addition, combining transmission electron microscopy ex-situ/in-situ characterization with first-principles calculations, it is shown that the χ-AgMg interface phase will be destroyed due to the diffusion of the outer Ag layer during thermal exposure, and gradually dissolve into the matrix, but it can still delay the coarsening behavior of θ′-Al2Cu phase. (3) The criteria for determining whether Ω phase can precipitate are updated in Al-Cu-Mg-Ag-Si alloys with low Mg/Si ratio based on phase diagram thermodynamic calculations and multi-scale structural characterization. When W(Mg)/W(Si) > 1.4 and X(Ag)/X(Mgexcess) > 1, Ω phase can precipitate in Al-Cu-Mg-Ag-Si alloys, where X(Mgexcess) represents the atomic percentage of residual Mg elements after the formation of the AlMgSiCu quaternary precipitate phase C/L phase in the supersaturated solid solution, and the W(Mg) is the mass fraction of Mg in the supersaturated solid solution before artificial ageing. (4) The effects of alloy element content on precipitation behavior and heat resistance of Al-Cu-Mg-Ag-Si alloys were systematically analyzed. Critical conditions for the precipitation of σ-Al5Cu6Mg2 and Ω phase in Al-Cu-Mg-Ag-Si alloys are revealed. Based on calculation of phase diagram results, the conditions for precipitating σ-Al5Cu6Mg2 phase in the alloy are: ① W(Mg)/W(Si) > 1.8; ② W(Cu) > 2.7W(Mg) – 5W(Si). When W(Mg)/W(Si) < 1.8, the alloy is mainly precipitated with C/L/Q′-AlMgSiCu. When W(Cu) < 2.7W(Mg) – 5W(Si), the alloy will generate GPB zone. In addition, W(Ag)/W(Si) > 4 is the critical condition which the Ω phase can the main precipitates in Al-Cu-Mg-Ag-Si alloys. Furthermore, the correlation between precipitate types and heat resistance was summarized, showing that Al-Cu-Mg-Ag-(Si) alloys with Ω phase as the main strengthening phase are more suitable for the preparation of structures with short service time but high temperature, while Al-Cu-Mg-Ag-(Si) alloys with low Mg content and multiple segregation structures are more suitable for structures requiring long-term service at medium to high temperatures. This study, for the first time, combines calculation of phase diagram with multi-scale microstructure characterization, systematically unraveling the effects of element content on precipitation behavior, strength, and heat resistance of Al-Cu-Mg-Ag-(Si) alloys. In addition, a concept of constructing a multiple interface segregation structure at the precipitate/matrix interface was proposed to synergistically improve alloy strength and heat resistance. This work provides theoretical guidance for optimizing the composition and processing of Al-Cu-Mg-Ag-(Si) alloy and regulating the microstructure. Furthermore, it also offers new ideas and theoretical guidance for the development of novel high-strength heat-resistant alloys in other systems. |
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UA library record |
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Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:206180 |
Serial |
9167 |
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Author |
Gogoi, A.; Neyts, E.C.; Peeters, F.M. |
Title |
Reduction-enhanced water flux through layered graphene oxide (GO) membranes stabilized with H3O+ and OH- ions |
Type |
A1 Journal article |
Year |
2024 |
Publication |
Physical chemistry, chemical physics |
Abbreviated Journal |
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Volume |
26 |
Issue |
13 |
Pages |
10265-10272 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Modelling and Simulation in Chemistry (MOSAIC) |
Abstract |
Graphene oxide (GO) is one of the most promising candidates for next generation of atomically thin membranes. Nevertheless, one of the major issues for real world application of GO membranes is their undesirable swelling in an aqueous environment. Recently, we demonstrated that generation of H3O+ and OH- ions (e.g., with an external electric field) in the interlayer gallery could impart aqueous stability to the layered GO membranes (A. Gogoi, ACS Appl. Mater. Interfaces, 2022, 14, 34946). This, however, compromises the water flux through the membrane. In this study, we report on reducing the GO nanosheets as a solution to this issue. With the reduction of the GO nanosheets, the water flux through the layered GO membrane initially increases and then decreases again beyond a certain degree of reduction. Here, two key factors are at play. Firstly, the instability of the H-bond network between water molecules and the GO nanosheets, which increases the water flux. Secondly, the pore size reduction in the interlayer gallery of the membranes, which decreases the water flux. We also observe a significant improvement in the salt rejection of the membranes, due to the dissociation of water molecules in the interlayer gallery. In particular, for the case of 10% water dissociation, the water flux through the membranes can be enhanced without altering its selectivity. This is an encouraging observation as it breaks the traditional tradeoff between water flux and salt rejection of a membrane. |
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001186465400001 |
Publication Date |
2024-03-15 |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1463-9076; 1463-9084 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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: 4.123 |
Call Number |
UA @ admin @ c:irua:204792 |
Serial |
9168 |
Permanent link to this record |