Home | << 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 >> |
![]() |
Records | |||||
---|---|---|---|---|---|
Author | van der Stam, W.; Geuchies, J.J.; Altantzis, T.; van den Bos, K.H.W.; Meeldijk, J.D.; Van Aert, S.; Bals, S.; Vanmaekelbergh, D.; de Mello Donega, C. | ||||
Title | Highly Emissive Divalent-Ion-Doped Colloidal CsPb1–xMxBr3Perovskite Nanocrystals through Cation Exchange | Type | A1 Journal article | ||
Year | 2017 | Publication | Journal of the American Chemical Society | Abbreviated Journal | J Am Chem Soc |
Volume | 139 | Issue | 139 | Pages | 4087-4097 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Colloidal CsPbX3 (X = Br, Cl, and I) perovskite nanocrystals (NCs) have emerged as promising phosphors and solar cell materials due to their remarkable optoelectronic properties. These properties can be tailored by not only controlling the size and shape of the NCs but also postsynthetic composition tuning through topotactic anion exchange. In contrast, property control by cation exchange is still underdeveloped for colloidal CsPbX3 NCs. Here, we present a method that allows partial cation exchange in colloidal CsPbBr3 NCs, whereby Pb2+ is exchanged for several isovalent cations, resulting in doped CsPb1−xMxBr3 NCs (M= Sn2+, Cd2+, and Zn2+; 0 < x ≤ 0.1), with preservation of the original NC shape. The size of the parent NCs is also preserved in the product NCs, apart from a small (few %) contraction of the unit cells upon incorporation of the guest cations. The partial Pb2+ for M2+ exchange leads to a blue-shift of the optical spectra, while maintaining the high photoluminescence quantum yields (>50%), sharp absorption features, and narrow emission of the parent CsPbBr3 NCs. The blue-shift in the optical spectra is attributed to the lattice contraction that accompanies the Pb2+ for M2+ cation exchange and is observed to scale linearly with the lattice contraction. This work opens up new possibilities to engineer the properties of halide perovskite NCs, which to date are demonstrated to be the only known system where cation and anion exchange reactions can be sequentially combined while preserving the original NC shape, resulting in compositionally diverse perovskite NCs. |
||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language ![]() |
Wos | 000397477700027 | Publication Date | 2017-03-10 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0002-7863 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 13.858 | Times cited | 535 | Open Access | OpenAccess |
Notes | W.v.d.S. and C.d.M.D. acknowledge financial support from the division of Chemical Sciences (CW) of The Netherlands Organization for Scientific Research (NWO) under grant number ECHO.712.012.001. J.J.G. and D.V. acknowledge financial support from the Debye Graduate program. S.B. acknowledges financial support from the European Research Council (ERC Starting Grant # 335078-COLOURATOMS). K.H.W.v.d.B., S.B., S.V.A. and T.A. acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0374.13N, G.0368.15N, G.0369.15N), a Ph.D. grant to K.H.W.v.d.B, and a postdoctoral research grant to T.A. (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); ECAS_Sara | Approved | Most recent IF: 13.858 | ||
Call Number | EMAT @ emat @ c:irua:141754UA @ admin @ c:irua:141754 | Serial | 4482 | ||
Permanent link to this record | |||||
Author | Martens, J.A.; Bogaerts, A.; De Kimpe, N.; Jacobs, P.A.; Marin, G.B.; Rabaey, K.; Saeys, M.; Verhelst, S. | ||||
Title | The Chemical Route to a Carbon Dioxide Neutral World | Type | A1 Journal article | ||
Year | 2017 | Publication | Chemsuschem | Abbreviated Journal | Chemsuschem |
Volume | 10 | Issue | 10 | Pages | 1039-1055 |
Keywords | A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Excessive CO2 emissions in the atmosphere from anthropogenic activity can be divided into point sources and diffuse sources. The capture of CO2 from flue gases of large industrial installations and its conversion into fuels and chemicals with fast catalytic processes seems technically possible. Some emerging technologies are already being demonstrated on an industrial scale. Others are still being tested on a laboratory or pilot scale. These emerging chemical technologies can be implemented in a time window ranging from 5 to 20 years. The massive amounts of energy needed for capturing processes and the conversion of CO2 should come from low-carbon energy sources, such as tidal, geothermal, and nuclear energy, but also, mainly, from the sun. Synthetic methane gas that can be formed from CO2 and hydrogen gas is an attractive renewable energy carrier with an existing distribution system. Methanol offers advantages as a liquid fuel and is also a building block for the chemical industry. CO2 emissions from diffuse sources is a difficult problem to solve, particularly for CO2 emissions from road, water, and air transport, but steady progress in the development of technology for capturing CO2 from air is being made. It is impossible to ban carbon from the entire energy supply of mankind with the current technological knowledge, but a transition to a mixed carbon–hydrogen economy can reduce net CO2 emissions and ultimately lead to a CO2-neutral world. |
||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language ![]() |
Wos | 000398182800002 | Publication Date | 2017-02-24 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1864-5631 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 7.226 | Times cited | 75 | Open Access | OpenAccess |
Notes | This paper is written by members of the Royal Flemish Academy of Belgium for Science and the Arts (KVAB) and external experts. KVAB is acknowledged for supporting the writing and publishing of this viewpoint. Valuable suggestions made by colleagues Jan Kretzschmar, Stan Ulens, and Luc Sterckx are highly appreciated. Special thanks go to Mr. Bert Seghers and Mrs. N. Boelens of KVAB for practical assistance. Mr. Tim Lacoere is acknowledged for graphic design and layout of the figures, and Steven Heylen and Elke Verheyen are acknowledged for data collection and editorial assistance. | Approved | Most recent IF: 7.226 | ||
Call Number | PLASMANT @ plasmant @ c:irua:141916 | Serial | 4532 | ||
Permanent link to this record | |||||
Author | Verlackt, C.C.W.; Van Boxem, W.; Dewaele, D.; Lemière, F.; Sobott, F.; Benedikt, J.; Neyts, E.C.; Bogaerts, A. | ||||
Title | Mechanisms of Peptide Oxidation by Hydroxyl Radicals: Insight at the Molecular Scale | Type | A1 Journal article | ||
Year | 2017 | Publication | The journal of physical chemistry: C : nanomaterials and interfaces | Abbreviated Journal | J Phys Chem C |
Volume | 121 | Issue | 121 | Pages | 5787-5799 |
Keywords | A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Molecular dynamics (MD) simulations were performed to provide atomic scale insight in the initial interaction between hydroxyl radicals (OH) and peptide systems in solution. These OH radicals are representative reactive oxygen species produced by cold atmospheric plasmas. The use of plasma for biomedical applications is gaining increasing interest, but the fundamental mechanisms behind the plasma modifications still remain largely elusive. This study helps to gain more insight in the underlying mechanisms of plasma medicine but is also more generally applicable to peptide oxidation, of interest for other applications. Combining both reactive and nonreactive MD simulations, we are able to elucidate the reactivity of the amino acids inside the peptide systems and their effect on their structure up to 1 μs. Additionally, experiments were performed, treating the simulated peptides with a plasma jet. The computational results presented here correlate well with the obtained experimental data and highlight the importance of the chemical environment for the reactivity of the individual amino acids, so that specific amino acids are attacked in higher numbers than expected. Furthermore, the long time scale simulations suggest that a single oxidation has an effect on the 3D conformation due to an increase in hydrophilicity and intra- and intermolecular interactions. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language ![]() |
Wos | 000396969900037 | Publication Date | 2017-03-16 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1932-7447 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.536 | Times cited | 5 | Open Access | OpenAccess |
Notes | Fonds Wetenschappelijk Onderzoek, G012413N ; | Approved | Most recent IF: 4.536 | ||
Call Number | PLASMANT @ plasmant @ c:irua:142202 | Serial | 4537 | ||
Permanent link to this record | |||||
Author | Mernissi Cherigui, E.A.; Sentosun, K.; Bouckenooge, P.; Vanrompay, H.; Bals, S.; Terryn, H.; Ustarroz, J. | ||||
Title | A Comprehensive Study of the Electrodeposition of Nickel Nanostructures from Deep Eutectic Solvents: Self-Limiting Growth by Electrolysis of Residual Water | Type | A1 Journal article | ||
Year | 2017 | Publication | The journal of physical chemistry: C : nanomaterials and interfaces | Abbreviated Journal | J Phys Chem C |
Volume | 121 | Issue | 121 | Pages | 9337-9347 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | The electrodeposition of nickel nanostructures on glassy carbon was investigated in 1:2 choline chloride – urea (1:2 ChCl-U) deep eutectic solvent (DES). By combining electrochemical techniques with ex-situ FE-SEM, XPS, HAADF-STEM and EDX, the electrochemical processes occurring during nickel deposition were better understood. Special attention was given to the interaction between the solvent and the growing nickel nanoparticles. The application of a suffciently negative potential results into the electrocatlytic hydrolisis of residual water in the DES, which leads to the formation of a mixed layer of Ni/Ni(OH)2(ads). In addition, hydrogen bonds between hydroxide species and the DES components could be formed, quenching the growth of the nickel clusters favouring their aggregation. Due to these processes, a highly dense distribution of nickel nanostructures can be obtained within a wide potential range. Understanding the role of residual water and the interactions at the interface during metal electrodeposition from DESs is essential to produce supported nanostructures in a controllable way for a broad range of applications and technologies. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language ![]() |
Wos | 000400881100027 | Publication Date | 2017-04-12 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1932-7447 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.536 | Times cited | 66 | Open Access | OpenAccess |
Notes | E.A. Mernissi Cherigui acknowledges funding from the Fonds Wetenschappelijk Onderzoek in Flanders (FWO, research project G019014N). S. Bals acknowledges funding from the European Research Council (Starting Grant No. COLOURATOMS 335078). H.V. gratefully acknowledges financial support by the Flemish Fund for Scientific Research (FWO Vlaanderen). Finally, J. Ustarroz acknowledges funding from the Fonds Wetenschappelijk Onderzoek in Flanders (FWO, postdoctoral grant 12I7816N). (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); ECAS_Sara | Approved | Most recent IF: 4.536 | ||
Call Number | EMAT @ emat @ c:irua:142208UA @ admin @ c:irua:142208 | Serial | 4551 | ||
Permanent link to this record | |||||
Author | Khalilov, U.; Bogaerts, A.; Neyts, E.C. | ||||
Title | Toward the Understanding of Selective Si Nano-Oxidation by Atomic Scale Simulations | Type | A1 Journal article | ||
Year | 2017 | Publication | Accounts of chemical research | Abbreviated Journal | Accounts Chem Res |
Volume | 50 | Issue | 50 | Pages | 796-804 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | The continuous miniaturization of nanodevices, such as transistors, solar cells, and optical fibers, requires the controlled synthesis of (ultra)thin gate oxides (<10 nm), including Si gate-oxide (SiO2) with high quality at the atomic scale. Traditional thermal growth of SiO2 on planar Si surfaces, however, does not allow one to obtain such ultrathin oxide due to either the high oxygen diffusivity at high temperature or the very low sticking ability of incident oxygen at low temperature. Two recent techniques, both operative at low (room) temperature, have been put forward to overcome these obstacles: (i) hyperthermal oxidation of planar Si surfaces and (ii) thermal or plasma-assisted oxidation of nonplanar Si surfaces, including Si nanowires (SiNWs). These nanooxidation processes are, however, often difficult to study experimentally, due to the key intermediate processes taking place on the nanosecond time scale. In this Account, these Si nano-oxidation techniques are discussed from a computational point of view and compared to both hyperthermal and thermal oxidation experiments, as well as to well-known models of thermal oxidation, including the Deal−Grove, Cabrera−Mott, and Kao models and several alternative mechanisms. In our studies, we use reactive molecular dynamics (MD) and hybrid MD/Monte Carlo simulation techniques, applying the Reax force field. The incident energy of oxygen species is chosen in the range of 1−5 eV in hyperthermal oxidation of planar Si surfaces in order to prevent energy-induced damage. It turns out that hyperthermal growth allows for two growth modes, where the ultrathin oxide thickness depends on either (1) only the kinetic energy of the incident oxygen species at a growth temperature below Ttrans = 600 K, or (2) both the incident energy and the growth temperature at a growth temperature above Ttrans. These modes are specific to such ultrathin oxides, and are not observed in traditional thermal oxidation, nor theoretically considered by already existing models. In the case of thermal or plasma-assisted oxidation of small Si nanowires, on the other hand, the thickness of the ultrathin oxide is a function of the growth temperature and the nanowire diameter. Below Ttrans, which varies with the nanowire diameter, partially oxidized SiNW are formed, whereas complete oxidation to a SiO2 nanowire occurs only above Ttrans. In both nano-oxidation processes at lower temperature (T < Ttrans), final sandwich c-Si|SiOx|a-SiO2 structures are obtained due to a competition between overcoming the energy barrier to penetrate into Si subsurface layers and the compressive stress (∼2−3 GPa) at the Si crystal/oxide interface. The overall atomic-simulation results strongly indicate that the thickness of the intermediate SiOx (x < 2) region is very limited (∼0.5 nm) and constant irrespective of oxidation parameters. Thus, control over the ultrathin SiO2 thickness with good quality is indeed possible by accurately tuning the oxidant energy, oxidation temperature and surface curvature. In general, we discuss and put in perspective these two oxidation mechanisms for obtaining controllable ultrathin gate-oxide films, offering a new route toward the fabrication of nanodevices via selective nano-oxidation. |
||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language ![]() |
Wos | 000399859800016 | Publication Date | 2017-04-18 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0001-4842 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 20.268 | Times cited | 5 | Open Access | OpenAccess |
Notes | Fonds Wetenschappelijk Onderzoek, 12M1315N ; | Approved | Most recent IF: 20.268 | ||
Call Number | PLASMANT @ plasmant @ c:irua:142638 | Serial | 4561 | ||
Permanent link to this record | |||||
Author | Berthelot, A.; Bogaerts, A. | ||||
Title | Modeling of CO2Splitting in a Microwave Plasma: How to Improve the Conversion and Energy Efficiency | Type | A1 Journal article | ||
Year | 2017 | Publication | The journal of physical chemistry: C : nanomaterials and interfaces | Abbreviated Journal | J Phys Chem C |
Volume | 121 | Issue | 121 | Pages | 8236-8251 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Microwave plasmas are one of the most promising techniques for CO2 conversion into value-added chemicals and fuels since they are very energy efficient. Nevertheless, experiments show that this high energy efficiency is only reached at low pressures and significantly drops toward atmospheric pressure, which is a clear limitation for industrial applications. In this paper, we use a zerodimensional reaction kinetics model to simulate a CO2 microwave plasma in a pressure range from 50 mbar to 1 bar, in order to evaluate the reasons for this decrease in energy efficiency at atmospheric pressure. The code includes a detailed description of the vibrational kinetics of CO2, CO, and O2 as well as the energy exchanges between them because the vibrational kinetics is known to be crucial for energy efficient CO2 splitting. First, we use a self-consistent gas temperature calculation in order to assess the key performance indicators for CO2 splitting, i.e., the CO2 conversion and corresponding energy efficiency. Our results indicate that lower pressures and higher power densities lead to more vibrational excitation, which is beneficial for the conversion. We also demonstrate the key role of the gas temperature. The model predicts the highest conversion and energy efficiencies at pressures around 300 mbar, which is in agreement with experiments from the literature. We also show the beneficial aspect of fast gas cooling in the afterglow at high pressure. In a second step, we study in more detail the effects of pressure, gas temperature, and power density on the vibrational distribution function and on the dissociation and recombination mechanisms of CO2, which define the CO2 splitting efficiency. This study allows us to identify the limiting factors of CO2 conversion and to propose potential solutions to improve the process. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language ![]() |
Wos | 000400039300002 | Publication Date | 2017-04-20 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1932-7447 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.536 | Times cited | 47 | Open Access | OpenAccess |
Notes | Federaal Wetenschapsbeleid; | Approved | Most recent IF: 4.536 | ||
Call Number | PLASMANT @ plasmant @ c:irua:142809 | Serial | 4567 | ||
Permanent link to this record | |||||
Author | Peters, J.L.; van den Bos, K.H.W.; Van Aert, S.; Goris, B.; Bals, S.; Vanmaekelbergh, D. | ||||
Title | Ligand-Induced Shape Transformation of PbSe Nanocrystals | Type | A1 Journal article | ||
Year | 2017 | Publication | Chemistry of materials | Abbreviated Journal | Chem Mater |
Volume | 29 | Issue | 29 | Pages | 4122-4128 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | We present a study of the relation between the surface chemistry and nanocrystal shape of PbSe nanocrystals with a variable Pb-to-Se stoichiometry and density of oleate ligands. The oleate ligand density and binding configuration are monitored by nuclear magnetic resonance and Fourier transform infrared absorbance spectroscopy, allowing us to quantify the number of surface-attached ligands per NC and the nature of the surface−Pb−oleate configuration. The three-dimensional shape of the PbSe nanocrystals is obtained from high-angle annular dark field scanning transmission electron microscopy combined with an atom counting method. We show that the enhanced oleate capping results in a stabilization and extension of the {111} facets, and a crystal shape transformation from a truncated nanocube to a truncated octahedron. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language ![]() |
Wos | 000401221700034 | Publication Date | 2017-05-09 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0897-4756 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 9.466 | Times cited | 45 | Open Access | OpenAccess |
Notes | D.V. acknowledges the European Research Council, ERC advanced grant, Project 692691-First Step, for financial support. We also acknowledge the Dutch FOM programme “Designing Dirac carriers in honeycomb semiconductor superlattices” (FOM Program 152) for financial support. The authors gratefully acknowledge funding from the Research Foundation Flanders (G.036915, G.037413, and funding of a Ph.D. research grant to K.H.W.v.d.B. and a postdoctoral grant to B.G.). S.B. acknowledges the European Research Council, ERC Grant 335078-Colouratom. (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); ECAS_Sara | Approved | Most recent IF: 9.466 | ||
Call Number | EMAT @ emat @ c:irua:143750 c:irua:142983UA @ admin @ c:irua:143750 | Serial | 4571 | ||
Permanent link to this record | |||||
Author | Wang, W.; Patil, B.; Heijkers, S.; Hessel, V.; Bogaerts, A. | ||||
Title | Nitrogen Fixation by Gliding Arc Plasma: Better Insight by Chemical Kinetics Modelling | Type | A1 Journal Article | ||
Year | 2017 | Publication | Chemsuschem | Abbreviated Journal | Chemsuschem |
Volume | 10 | Issue | 10 | Pages | 2110-2110 |
Keywords | A1 Journal Article; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ; | ||||
Abstract | The conversion of atmospheric nitrogen into valuable compounds, that is, so-called nitrogen fixation, is gaining increased interest, owing to the essential role in the nitrogen cycle of the biosphere. Plasma technology, and more specifically gliding arc plasma, has great potential in this area, but little is known about the underlying mechanisms. Therefore, we developed a detailed chemical kinetics model for a pulsed-power gliding-arc reactor operating at atmospheric pressure for nitrogen oxide synthesis. Experiments are performed to validate the model and reasonable agreement is reached between the calculated and measured NO and NO2 yields and the corresponding energy efficiency for NOx formation for different N2/O2 ratios, indicating that the model can provide a realistic picture of the plasma chemistry. Therefore, we can use the model to investigate the reaction pathways for the formation and loss of NOx. The results indicate that vibrational excitation of N2 in the gliding arc contributes significantly to activating the N2 molecules, and leads to an energy efficient way of NOx production, compared to the thermal process. Based on the underlying chemistry, the model allows us to propose solutions on how to further improve the NOx formation by gliding arc technology. Although the energy efficiency of the gliding-arc-based nitrogen fixation process at the present stage is not comparable to the world-scale Haber–Bosch process, we believe our study helps us to come up with more realistic scenarios of entering a cutting-edge innovation in new business cases for the decentralised production of fertilisers for agriculture, in which lowtemperature plasma technology might play an important role. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language ![]() |
Wos | Publication Date | 2017-05-11 | ||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1864-5631 | ISBN | Additional Links | ||
Impact Factor | 7.226 | Times cited | Open Access | Not_Open_Access | |
Notes | This research was supported by the European Marie Skłodowska- Curie Individual Fellowship “GlidArc” within Horizon 2020 (Grant No.657304), by the FWO project (grant G.0383.16 N) and by the EU project MAPSYN: Microwave, Acoustic and Plasma assisted SYNthesis, under the grant agreement no. CP-IP 309376 of the European Community’s Seventh Framework Program. The calculations were performed using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen (UAntwerpen), a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the UAntwerpen. | Approved | Most recent IF: 7.226 | ||
Call Number | PLASMANT @ plasmant @ | Serial | 4573 | ||
Permanent link to this record | |||||
Author | Saniz, R.; Bekaert, J.; Partoens, B.; Lamoen, D. | ||||
Title | Structural and electronic properties of defects at grain boundaries in CuInSe2 | Type | A1 Journal article | ||
Year | 2017 | Publication | Physical chemistry, chemical physics | Abbreviated Journal | Phys Chem Chem Phys |
Volume | 19 | Issue | 19 | Pages | 14770-14780 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) | ||||
Abstract | We report on a first-principles study of the structural and electronic properties of a Sigma3 (112) grain boundary model in CuInSe2. The study focuses on a coherent, stoichiometry preserving, cation–Se terminated grain boundary, addressing the properties of the grain boundary as such, as well as the effect of well known defects in CuInSe2. We show that in spite of its apparent simplicity, such a grain boundary exhibits a very rich phenomenology, providing an explanation for several of the experimentally observed properties of grain boundaries in CuInSe2 thin films. In particular, we show that the combined effect of Cu vacancies and cation antisites can result in the observed Cu depletion with no In enrichment at the grain boundaries. Furthermore, Cu vacancies are unlikely to produce a hole barrier at the grain boundaries, but Na may indeed have such an effect. We find that Na-on-Cu defects will tend to form abundantly at the grain boundaries, and can provide a mechanism for the carrier depletion and/or type inversion experimentally reported. |
||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language ![]() |
Wos | 000403327200059 | Publication Date | 2017-05-12 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1463-9076 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.123 | Times cited | 12 | Open Access | OpenAccess |
Notes | We thank B. Schoeters for his assistance running the GBstudio software. We acknowledge the financial support of FWO-Vlaanderen through project G.0150.13. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by FWO-Vlaanderen and the Flemish Government-department EWI. | Approved | Most recent IF: 4.123 | ||
Call Number | EMAT @ emat @ c:irua:143869 | Serial | 4577 | ||
Permanent link to this record | |||||
Author | Ben Hafsia, A.; Hendrickx, M.; Batuk, M.; Khitouni, M.; Hadermann, J.; Greneche, J.-M.; Rammeh, N. | ||||
Title | Crystal structure study of manganese and titanium substituted BaLaFe2O6-δ | Type | A1 Journal article | ||
Year | 2017 | Publication | Journal of solid state chemistry | Abbreviated Journal | J Solid State Chem |
Volume | 251 | Issue | 251 | Pages | 186-193 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Barium lanthanum ferrite and four Mn/Ti substituted materials were synthesized by the sol-gel method. The crystal structure of the materials was studied by a combination of X-ray powder diffraction, electron diffraction, scanning transmission electron microscopy and 57Fe Mössbauer spectrometry. BaLaFe2O6-δ has a cubic perovskite structure and Ba0.7La1.3FeMnO6-δ is distorted perovskite with the R-3c symmetry, both from electron diffraction and X-ray powder diffraction. However, according to transmission electron microscopy, the crystals of BaLaFeTiO6-δ, BaLaFeTi0.5Mn0.5O6-δ, and BaLaFe0.5Ti0.5MnO6-δ consist of nanodomains with different symmetries (Pm3m next to R-3c due to octahedral tilts), whereas the bulk X-ray powder diffraction patterns for these compounds correspond to the simple cubic structure. 57Fe Mössbauer spectrometry confirms that all materials contain high spin state Fe3+ ions which are strongly influenced by the chemical disorder resulting from various cationic environments. |
||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language ![]() |
Wos | 000402581200024 | Publication Date | 2017-04-20 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0022-4596 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.299 | Times cited | Open Access | Not_Open_Access | |
Notes | This study has been supported by the Tunisian Ministry of Higher Education and Scientific Research and by the University of Antwerp BOF Grant 33024 funding scheme. | Approved | Most recent IF: 2.299 | ||
Call Number | EMAT @ emat @ c:irua:143988 | Serial | 4582 | ||
Permanent link to this record | |||||
Author | Wang, W.; Mei, D.; Tu, X.; Bogaerts, A. | ||||
Title | Gliding arc plasma for CO 2 conversion: Better insights by a combined experimental and modelling approach | Type | A1 Journal article | ||
Year | 2017 | Publication | Chemical engineering journal | Abbreviated Journal | Chem Eng J |
Volume | 330 | Issue | Pages | 11-25 | |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | A gliding arc plasma is a potential way to convert CO2 into CO and O2, due to its non-equilibrium character, but little is known about the underlying mechanisms. In this paper, a self-consistent two-dimensional (2D) gliding arc model is developed, with a detailed non-equilibrium CO2 plasma chemistry, and validated with experiments. Our calculated values of the electron number density in the plasma, the CO2 conversion and energy efficiency show reasonable agreement with the experiments, indicating that the model can provide a realistic picture of the plasma chemistry. Comparison of the results with classical thermal conversion, as well as other plasma-based technologies for CO2 conversion reported in literature, demonstrates the non-equilibrium character of the gliding arc, and indicates that the gliding arc is a promising plasma reactor for CO2 conversion. However, some process modifications should be exploited to further improve its performance. As the model provides a realistic picture of the plasma behaviour, we use it first to investigate the plasma characteristics in a whole gliding arc cycle, which is necessary to understand the underlying mechanisms. Subsequently, we perform a chemical kinetics analysis, to investigate the different pathways for CO2 loss and formation. Based on the revealed discharge properties and the underlying CO2 plasma chemistry, the model allows us to propose solutions on how to further improve the CO2 conversion and energy efficiency by a gliding arc plasma. |
||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language ![]() |
Wos | 000414083300002 | Publication Date | 2017-07-22 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1385-8947 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 6.216 | Times cited | 38 | Open Access | OpenAccess |
Notes | This research was supported by the European Marie Skłodowska- Curie Individual Fellowship “GlidArc” within Horizon 2020 (Grant No. 657304) and by the FWO project (grant G.0383.16N). The support of this experimental work by the EPSRC CO2Chem Seedcorn Grant and the FWO travel grant for study abroad (Grant K2.128.17N) is gratefully acknowledged. The calculations were performed using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen (UAntwerpen), a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the UAntwerpen. | Approved | Most recent IF: 6.216 | ||
Call Number | PLASMANT @ plasmant @c:irua:145033 | Serial | 4636 | ||
Permanent link to this record | |||||
Author | Ramakers, M.; Trenchev, G.; Heijkers, S.; Wang, W.; Bogaerts, A. | ||||
Title | Gliding Arc Plasmatron: Providing an Alternative Method for Carbon Dioxide Conversion | Type | A1 Journal article | ||
Year | 2017 | Publication | Chemsuschem | Abbreviated Journal | Chemsuschem |
Volume | 10 | Issue | 10 | Pages | 2642-2652 |
Keywords | A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Low-temperature plasmas are gaining a lot of interest for environmental and energy applications. A large research field in these applications is the conversion of CO2 into chemicals and fuels. Since CO2 is a very stable molecule, a key performance indicator for the research on plasma-based CO2 conversion is the energy efficiency. Until now, the energy efficiency in atmospheric plasma reactors is quite low, and therefore we employ here a novel type of plasma reactor, the gliding arc plasmatron (GAP). This paper provides a detailed experimental and computational study of the CO2 conversion, as well as the energy cost and efficiency in a GAP. A comparison with thermal conversion, other plasma types and other novel CO2 conversion technologies is made to find out whether this novel plasma reactor can provide a significant contribution to the much-needed efficient conversion of CO2. From these comparisons it becomes evident that our results are less than a factor of two away from being cost competitive and already outperform several other new technologies. Furthermore, we indicate how the performance of the GAP can still be improved by further exploiting its non-equilibrium character. Hence, it is clear that the GAP is very promising for CO2 conversion. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language ![]() |
Wos | 000403934400014 | Publication Date | 2017-05-22 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1864-5631 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 7.226 | Times cited | 42 | Open Access | OpenAccess |
Notes | Federaal Wetenschapsbeleid; Fonds Wetenschappelijk Onderzoek, G.0383.16N 11U5316N ; Horizon 2020, 657304 ; | Approved | Most recent IF: 7.226 | ||
Call Number | PLASMANT @ plasmant @ c:irua:144184 | Serial | 4616 | ||
Permanent link to this record | |||||
Author | Michielsen, I.; Uytdenhouwen, Y.; Pype, J.; Michielsen, B.; Mertens, J.; Reniers, F.; Meynen, V.; Bogaerts, A. | ||||
Title | CO 2 dissociation in a packed bed DBD reactor: First steps towards a better understanding of plasma catalysis | Type | A1 Journal article | ||
Year | 2017 | Publication | Chemical engineering journal | Abbreviated Journal | Chem Eng J |
Volume | 326 | Issue | 326 | Pages | 477-488 |
Keywords | A1 Journal article; Laboratory of adsorption and catalysis (LADCA); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Plasma catalysis is gaining increasing interest for CO2 conversion, but the interaction between the plasma and catalyst is still poorly understood. This is caused by limited systematic materials research, since most works combine a plasma with commercial supported catalysts and packings. In the present paper, we study the influence of specific material and reactor properties, as well as reactor/bead configuration, on the conversion and energy efficiency of CO2 dissociation in a packed bed dielectric barrier discharge (DBD) reactor. Of the various packing materials investigated, BaTiO3 yields the highest conversion and energy efficiency, i.e., 25% and 4.5%. Our results show that, when evaluating the influence of catalysts, the impact of the packing (support) material itself cannot be neglected, since it can largely affect the conversion and energy efficiency. This shows the large potential for further improvement of packed bed plasma reactors for CO2 conversion and other chemical conversion reactions by adjusting both packing (support) properties and catalytically active sites. Moreover, we clearly prove that comparison of results obtained in different reactor setups should be done with care, since there is a large effect of the reactor setup and reactor/bead configuration. |
||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language ![]() |
Wos | 000406137200047 | Publication Date | 2017-06-01 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1385-8947 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 6.216 | Times cited | 49 | Open Access | OpenAccess |
Notes | This research was carried out with financial support of the Institute for the Promotion of Innovation by Science and Technology in Flanders (IWT Flanders) for both I. Michielsen (IWT-141093) and J. Pype (IWT-131229) and of the Walloon region through the excellence programme FLYCOAT (nr. 1318147) for the profilometry measurements. The authors also acknowledge financial support from an IOF-SBO project from the University of Antwerp and from the Fund for Scientific Research (FWO; grant number: G.0254.14 N). This research was carried out in the framework of the network on Physical Chemistry of Plasma-Surface Interactions – Interuniversity Attraction Poles, phase VII (http://psi-iap7.ulb. ac.be/), and supported by the Belgian Science Policy Office (BELSPO). The authors would also like to thank Koen Van Laer for the discussions on this manuscript. | Approved | Most recent IF: 6.216 | ||
Call Number | PLASMANT @ plasmant @ c:irua:144802 | Serial | 4626 | ||
Permanent link to this record | |||||
Author | Shirazi, M.; Bogaerts, A.; Neyts, E.C. | ||||
Title | A DFT study of H-dissolution into the bulk of a crystalline Ni(111) surface: a chemical identifier for the reaction kinetics | Type | A1 Journal article | ||
Year | 2017 | Publication | Physical chemistry, chemical physics | Abbreviated Journal | Phys Chem Chem Phys |
Volume | 19 | Issue | 19 | Pages | 19150-19158 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | In this study, we investigated the diffusion of H-atoms to the subsurface and their further diffusion into the bulk of a Ni(111) crystal by means of density functional theory calculations in the context of thermal and plasma-assisted catalysis. The H-atoms at the surface can originate from the dissociative adsorption of H2 or CH4 molecules, determining the surface H-coverage. When a threshold H-coverage is passed, corresponding to 1.00 ML for the crystalline Ni(111) surface, the surface-bound H-atoms start to diffuse to the subsurface. A similar threshold coverage is observed for the interstitial H-coverage. Once the interstitial sites are filled up with a coverage above 1.00 ML of H, dissolution of interstitial H-atoms to the layer below the interstitial sites will be initiated. Hence, by applying a high pressure or inducing a reactive plasma and high temperature, increasing the H-flux to the surface, a large amount of hydrogen can diffuse in a crystalline metal like Ni and can be absorbed. The formation of metal hydride may modify the entire reaction kinetics of the system. Equivalently, the H-atoms in the bulk can easily go back to the surface and release a large amount of heat. In a plasma process, H-atoms are formed in the plasma, and therefore the energy barrier for dissociative adsorption is dismissed, thus allowing achievement of the threshold coverage without applying a high pressure as in a thermal process. As a result, depending on the crystal plane and type of metal, a large number of H-atoms can be dissolved (absorbed) in the metal catalyst, explaining the high efficiency of plasma-assisted catalytic reactions. Here, the mechanism of H-dissolution is established as a chemical identifier for the investigation of the reaction kinetics of a chemical process. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language ![]() |
Wos | 000406334300034 | Publication Date | 2017-06-22 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1463-9076 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.123 | Times cited | 10 | Open Access | OpenAccess |
Notes | Financial support from the Reactive Atmospheric Plasma processIng – eDucation (RAPID) network, through the EU 7th Framework Programme (grant agreement no. 606889), is gratefully acknowledged. The calculations were performed using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen, a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government department (EWI) and the Universiteit Antwerpen. | Approved | Most recent IF: 4.123 | ||
Call Number | PLASMANT @ plasmant @ c:irua:144794 | Serial | 4633 | ||
Permanent link to this record | |||||
Author | Pulinthanathu Sree, S.; Dendooven, J.; Geerts, L.; Ramachandran, R.K.; Javon, E.; Ceyssens, F.; Breynaert, E.; Kirschhock, C.E.A.; Puers, R.; Altantzis, T.; Van Tendeloo, G.; Bals, S.; Detavernier, C.; Martens, J.A. | ||||
Title | 3D porous nanostructured platinum prepared using atomic layer deposition | Type | A1 Journal article | ||
Year | 2017 | Publication | Journal of materials chemistry A : materials for energy and sustainability | Abbreviated Journal | J Mater Chem A |
Volume | 5 | Issue | 5 | Pages | 19007-19016 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | A robust and easy to handle 3D porous platinum structure was created via replicating the 3D channel system of an ordered mesoporous silica material using atomic layer deposition (ALD) over micrometer distances. After ALD of Pt in the silica material, the host template was digested using hydrogen fluoride (HF). A fully connected ordered Pt nanostructure was obtained with morphology and sizes corresponding to that of the pores of the host matrix, as revealed with high-resolution scanning transmission electron microscopy and electron tomography. The Pt nanostructure consisted of hexagonal Pt rods originating from the straight mesopores (11 nm) of the host structure and linking features resulting from Pt replication of the interconnecting mesopore segments (2–4 nm) present in the silica host structure. Electron tomography of partial replicas, made by incomplete infilling of Zeotile-4 material with Pt, provided insight in the connectivity and formation mechanism of the Pt nanostructure by ALD. The Pt replica was evaluated for its potential use as electrocatalyst for the hydrogen evolution reaction, one of the half-reactions of water electrolysis, and as microelectrode for biomedical sensing. The Pt replica showed high activity for the hydrogen evolution reaction and electrochemical characterization revealed a large impedance improvement in comparison with reference Pt electrodes. |
||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language ![]() |
Wos | 000411232100010 | Publication Date | 2017-06-28 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2050-7488 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 8.867 | Times cited | 9 | Open Access | OpenAccess |
Notes | This work was supported by the Flemish government through long-term structural funding (Methusalem) to JAM and FWO for a research project (G0A5417N). JD, TA and FC acknowledge Flemish FWO for a post-doctoral fellowship. S. B. acknowledges funding from ERC Starting Grant COLOURATOMS (335078). (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); saraecas; ECAS_Sara; | Approved | Most recent IF: 8.867 | ||
Call Number | EMAT @ emat @ c:irua:144624 c:irua:144624 c:irua:144624UA @ admin @ c:irua:144624 | Serial | 4634 | ||
Permanent link to this record | |||||
Author | Debroye, E.; Yuan, H.; Bladt, E.; Baekelant, W.; Van der Auweraer, M.; Hofkens, J.; Bals, S.; Roeffaers, M.B.J. | ||||
Title | Facile morphology-controlled synthesis of organolead iodide perovskite nanocrystals using binary capping agents | Type | A1 Journal article | ||
Year | 2017 | Publication | ChemNanoMat : chemistry of nanomaterials for energy, biology and more | Abbreviated Journal | Chemnanomat |
Volume | 3 | Issue | 3 | Pages | 223-227 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Controlling the morphology of organolead halide perovskite crystals is crucial to a fundamental understanding of the materials and to tune their properties for device applications. Here, we report a facile solution-based method for morphology-controlled synthesis of rod-like and plate-like organolead halide perovskite nanocrystals using binary capping agents. The morphology control is likely due to an interplay between surface binding kinetics of the two capping agents at different crystal facets. By high-resolution scanning transmission electron microscopy, we show that the obtained nanocrystals are monocrystalline. Moreover, long photoluminescence decay times of the nanocrystals indicate long charge diffusion lengths and low trap/defect densities. Our results pave the way for large-scale solution synthesis of organolead halide perovskite nanocrystals with controlled morphology for future device applications. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language ![]() |
Wos | 000399604300003 | Publication Date | 2017-01-18 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2199-692x | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.937 | Times cited | 19 | Open Access | OpenAccess |
Notes | ; We acknowledge financial support from the Research Foundation-Flanders (FWO, grant G.0197.11, G.0962.13, G0B39.15, postdoctoral fellowship to E. D. and H. Y.), KU Leuven Research Fund (C14/15/053), the Flemish government through long term structural funding Methusalem (CASAS2, Meth/15/04), the Hercules foundation (HER/11/14), the Belgian Federal Science Policy Office (IAP-PH05), the EC through the Marie Curie ITN project iSwitch (GA-642196) and the ERC project LIGHT (GA307523). S. B. acknowledges financial support from European Research Council (ERC Starting Grant # 335078-COLOURATOMS). E. B. gratefully acknowledges financial support by the Flemish Fund for Scientific Research (FWO Vlaanderen). ; ecas_Sara | Approved | Most recent IF: 2.937 | ||
Call Number | UA @ lucian @ c:irua:143678UA @ admin @ c:irua:143678 | Serial | 4656 | ||
Permanent link to this record | |||||
Author | Berthold, T.; Castro, C.R.; Winter, M.; Hoerpel, G.; Kurttepeli, M.; Bals, S.; Antonietti, M.; Fechler, N. | ||||
Title | Tunable nitrogen-doped carbon nanoparticles from tannic acid and urea and their potential for sustainable soots | Type | A1 Journal article | ||
Year | 2017 | Publication | ChemNanoMat : chemistry of nanomaterials for energy, biology and more | Abbreviated Journal | Chemnanomat |
Volume | 3 | Issue | 3 | Pages | 311-318 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Nano-sized nitrogen-doped carbon spheres are synthesized from two cheap, readily available and sustainable precursors: tannic acid and urea. In combination with a polymer structuring agent, nitrogen content, sphere size and the surface (up to 400 m(2)g(-1)) can be conveniently tuned by the precursor ratio, temperature and structuring agent content. Because the chosen precursors allow simple oven synthesis and avoid harsh conditions, this carbon nanosphere platform offers a more sustainable alternative to classical soots, for example, as printing pigments or conduction soots. The carbon spheres are demonstrated to be a promising as conductive carbon additive in anode materials for lithium ion batteries. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language ![]() |
Wos | 000403299200006 | Publication Date | 2017-03-10 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2199-692x | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.937 | Times cited | 14 | Open Access | OpenAccess |
Notes | ; S.B. is grateful for funding by the European Research Council (ERC starting grant # 335078-COLOURATOMS). ; ecas_Sara | Approved | Most recent IF: 2.937 | ||
Call Number | UA @ lucian @ c:irua:144287UA @ admin @ c:irua:144287 | Serial | 4699 | ||
Permanent link to this record | |||||
Author | Benetti, G.; Caddeo, C.; Melis, C.; Ferrini, G.; Giannetti, C.; Winckelmans, N.; Bals, S.; J Van Bael, M.; Cavaliere, E.; Gavioli, L.; Banfi, F. | ||||
Title | Bottom-Up Mechanical Nanometrology of Granular Ag Nanoparticles Thin Films | Type | A1 Journal article | ||
Year | 2017 | Publication | The journal of physical chemistry: C : nanomaterials and interfaces | Abbreviated Journal | J Phys Chem C |
Volume | 121 | Issue | 121 | Pages | 22434-22441 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Ultrathin metal nanoparticles coatings, synthesized by gas-phase deposition, are emerging as go-to materials in a variety of fields ranging from pathogens control, sensing to energy storage. Predicting their morphology and mechanical properties beyond a trial-and-error approach is a crucial issue limiting their exploitation in real-life applications. The morphology and mechanical properties of Ag nanoparticles ultrathin films, synthesized by supersonic cluster beam deposition, are here assessed adopting a bottom-up, multi-technique approach. A virtual film model is proposed merging high resolution scanning transmission electron microscopy, supersonic cluster beam dynamics and molecular dynamics simulations. The model is validated against mechanical nanometrology measurements and is readily extendable to metals other than Ag. The virtual film is shown to be a flexible and reliable predictive tool to access morphology-dependent properties such as mesoscale gas-dynamics and elasticity of ultrathin films synthesized by gas-phase deposition. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language ![]() |
Wos | 000413131700072 | Publication Date | 2017-09-11 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1932-7447 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.536 | Times cited | 30 | Open Access | OpenAccess |
Notes | ; All authors thank Prof. Dr. Luciano Colombo for enlightening discussions. C.C. and F.B. acknowledge financial support from the MIUR Futuro in ricerca 2013 Grant in the frame of the ULTRANANO Project (Project No. RBFR13NEA4). F.B., G.F., and C.G. acknowledge support from Universita Cattolica del Sacro Cuore through D.2.2 and D.3.1 grants. F.B. acknowledges financial support from Fondazione E.U.L.O. The authors acknowledge financial support from the European Union through the seventh Framework Program (FP7) under a contract for an Integrated Infrastructure Initiative (Reference No. 312483 ESTEEM2). ; | Approved | Most recent IF: 4.536 | ||
Call Number | EMAT @ emat @c:irua:145828UA @ admin @ c:irua:145828 | Serial | 4706 | ||
Permanent link to this record | |||||
Author | Aussems, D.U.B.; Bal, K. M.; Morgan, T.W.; van de Sanden, M.C.M.; Neyts, E.C. | ||||
Title | Atomistic simulations of graphite etching at realistic time scales | Type | A1 Journal article | ||
Year | 2017 | Publication | Chemical science | Abbreviated Journal | Chem Sci |
Volume | 8 | Issue | 10 | Pages | 7160-7168 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Hydrogen–graphite interactions are relevant to a wide variety of applications, ranging from astrophysics to fusion devices and nano-electronics. In order to shed light on these interactions, atomistic simulation using Molecular Dynamics (MD) has been shown to be an invaluable tool. It suffers, however, from severe timescale limitations. In this work we apply the recently developed Collective Variable-Driven Hyperdynamics (CVHD) method to hydrogen etching of graphite for varying inter-impact times up to a realistic value of 1 ms, which corresponds to a flux of 1020 m2 s1. The results show that the erosion yield, hydrogen surface coverage and species distribution are significantly affected by the time between impacts. This can be explained by the higher probability of C–C bond breaking due to the prolonged exposure to thermal stress and the subsequent transition from ion- to thermal-induced etching. This latter regime of thermal-induced etching – chemical erosion – is here accessed for the first time using atomistic simulations. In conclusion, this study demonstrates that accounting for long time-scales significantly affects ion bombardment simulations and should not be neglected in a wide range of conditions, in contrast to what is typically assumed. |
||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language ![]() |
Wos | 000411730500055 | Publication Date | 2017-08-24 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2041-6520 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 8.668 | Times cited | 3 | Open Access | OpenAccess |
Notes | DIFFER is part of the Netherlands Organisation for Scientic Research (NWO). K. M. B. is funded as a PhD fellow (aspirant) of the FWO-Flanders (Fund for Scientic Research-Flanders), Grant 11V8915N. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the Research Foundation – Flanders (FWO) and the Flemish Government – department EWI. | Approved | Most recent IF: 8.668 | ||
Call Number | PLASMANT @ plasmant @c:irua:145519 | Serial | 4707 | ||
Permanent link to this record | |||||
Author | Snoeckx, R.; Bogaerts, A. | ||||
Title | Plasma technology – a novel solution for CO2conversion? | Type | A1 Journal article | ||
Year | 2017 | Publication | Chemical Society reviews | Abbreviated Journal | Chem Soc Rev |
Volume | 46 | Issue | 19 | Pages | 5805-5863 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | CO2 conversion into value-added chemicals and fuels is considered as one of the great challenges of the 21st century. Due to the limitations of the traditional thermal approaches, several novel technologies are being developed. One promising approach in this field, which has received little attention to date, is plasma technology. Its advantages include mild operating conditions, easy upscaling, and gas activation by energetic electrons instead of heat. This allows thermodynamically difficult reactions, such as CO2 splitting and the dry reformation of methane, to occur with reasonable energy cost. In this review, after exploring the traditional thermal approaches, we have provided a brief overview of the fierce competition between various novel approaches in a quest to find the most effective and efficient CO2 conversion technology. This is needed to critically assess whether plasma technology can be successful in an already crowded arena. The following questions need to be answered in this regard: are there key advantages to using plasma technology over other novel approaches, and if so, what is the flip side to the use of this technology? Can plasma technology be successful on its own, or can synergies be achieved by combining it with other technologies? To answer these specific questions and to evaluate the potentials and limitations of plasma technology in general, this review presents the current state-of-the-art and a critical assessment of plasma-based CO2 conversion, as well as the future challenges for its practical implementation. |
||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language ![]() |
Wos | 000412141600006 | Publication Date | 2017-08-21 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0306-0012 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 38.618 | Times cited | 168 | Open Access | OpenAccess |
Notes | We would like to thank W. Wang (University of Antwerp) for providing the data on the thermal equilibrium conversions. Furthermore, we acknowledge financial support from the IAP/7 (Inter-university Attraction Pole) programme ‘PSI-Physical Chemistry of Plasma-Surface Interactions’ by the Belgian Federal Office for Science Policy (BELSPO), the Methusalem financing of the University of Antwerp, the Fund for Scientific Research Flanders (FWO; Grant no. G.0383.16N, G.0254.14N and G.0217.14N), the TOP research project of the Research Fund of the University of Antwerp (grant ID. 32249). | Approved | Most recent IF: 38.618 | ||
Call Number | PLASMANT @ plasmant @c:irua:145921 | Serial | 4709 | ||
Permanent link to this record | |||||
Author | Rumyantseva, M.N.; Vladimirova, S.A.; Vorobyeva, N.A.; Giebelhaus, I.; Mathur, S.; Chizhov, A.S.; Khmelevsky, N.O.; Aksenenko, A.Y.; Kozlovsky, V.F.; Karakulina, O.M.; Hadermann, J.; Abakumov, A.M.; Gaskov, A.M. | ||||
Title | p -CoO x / n -SnO 2 nanostructures: New highly selective materials for H 2 S detection | Type | A1 Journal article | ||
Year | 2017 | Publication | Sensors and actuators : B : chemical | Abbreviated Journal | Sensor Actuat B-Chem |
Volume | Issue | Pages | |||
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Nanostructures p-CoOx/n-SnO2 based on tin oxide nanowires have been prepared by two step CVD technique and characterized in detail by XRD, XRF, XPS, HAADF-STEM imaging and EDX-STEM mapping. Depending on the temperature of decomposition of cobalt complex during the second step of CVD synthesis of nanostructures cobalt oxide forms a coating and/or isolated nanoparticles on SnO2 nanowire surface. It was found that cobalt presents in +2 and +3 oxidation states. The measurements of gas sensor properties have been carried out during exposure to CO (14 ppm), NH3 (21 ppm), and H2S (2 ppm) in dry air. The opposite trends were observed in the effect of cobalt oxide on the SnO2 gas sensitivity when detecting CO or NH3 in comparison to H2S. The decrease of sensor signal toward CO and NH3 was attributed to high catalytic activity of Co3O4 in oxidation of these gases. Contrary, the significant increase of sensor signal in the presence of H2S was attributed to the formation of metallic cobalt sulfide and removal of the barrier between p-CoOx and n-SnO2. This effect provides an excellent selectivity of p-CoOx/n-SnO2 nanostructures in H2S detection. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language ![]() |
Wos | 000414151800068 | Publication Date | 2017-08-17 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0925-4005 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 5.401 | Times cited | 13 | Open Access | Not_Open_Access: Available from 10.10.2019 |
Notes | ERA-Net.Plus, 096 FONSENS ; | Approved | Most recent IF: 5.401 | ||
Call Number | EMAT @ emat @c:irua:145926 | Serial | 4710 | ||
Permanent link to this record | |||||
Author | González-Rubio, G.; de Oliveira, T.M.; Altantzis, T.; La Porta, A.; Guerrero-Martínez, A.; Bals, S.; Scarabelli, L.; Liz-Marzán, L.M. | ||||
Title | Disentangling the effect of seed size and crystal habit on gold nanoparticle seeded growth | Type | A1 Journal article | ||
Year | 2017 | Publication | Chemical communications | Abbreviated Journal | Chem Commun |
Volume | 53 | Issue | 53 | Pages | 11360-11363 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Oxidative etching was used to produce gold seeds of different sizes and crystal habits. Following detailed characterization, the seeds were grown under different conditions. Our results bring new insights toward understanding the effect of size and crystallinity on the growth of anisotropic particles, whilst identifying guidelines for the optimisation of new synthetic protocols of predesigned seeds. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language ![]() |
Wos | 000412814900019 | Publication Date | 2017-09-26 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1359-7345 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 6.319 | Times cited | 29 | Open Access | OpenAccess |
Notes | This work was funded by the Spanish MINECO (grant # MAT2013-46101-R, Ramon y Cajal fellowship to A. G.-M. and FPI fellowship to G. G.-R.). Financial support is acknowledged from the European Commission (EUSMI, 731019). S. B. acknowledges financial support from the European Research Council (ERC Starting Grant # 335078-COLOURATOMS). T. A. acknowledges a postdoctoral grant from Research Foundation Flanders (FWO, Belgium). ECAS_Sara (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); | Approved | Most recent IF: 6.319 | ||
Call Number | EMAT @ emat @c:irua:146101UA @ admin @ c:irua:146101 | Serial | 4734 | ||
Permanent link to this record | |||||
Author | Cleiren, E.; Heijkers, S.; Ramakers, M.; Bogaerts, A. | ||||
Title | Dry Reforming of Methane in a Gliding Arc Plasmatron: Towards a Better Understanding of the Plasma Chemistry | Type | A1 Journal article | ||
Year | 2017 | Publication | Chemsuschem | Abbreviated Journal | Chemsuschem |
Volume | 10 | Issue | 20 | Pages | 4025-4036 |
Keywords | A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Dry reforming of methane (DRM) in a gliding arc plasmatron is studied for different CH4 fractions in the mixture. The CO2 and CH4 conversions reach their highest values of approximately 18 and 10%, respectively, at 25% CH4 in the gas mixture, corresponding to an overall energy cost of 10 kJ L@1 (or 2.5 eV per molecule) and an energy efficiency of 66%. CO and H2 are the major products, with the formation of smaller fractions of C2Hx (x=2, 4, or 6) compounds and H2O. A chemical kinetics model is used to investigate the underlying chemical processes. The calculated CO2 and CH4 conversion and the energy efficiency are in good agreement with the experimental data. The model calculations reveal that the reaction of CO2 (mainly at vibrationally excited levels) with H radicals is mainly responsible for the CO2 conversion, especially at higher CH4 fractions in the mixture, which explains why the CO2 conversion increases with increasing CH4 fraction. The main process responsible for CH4 conversion is the reaction with OH radicals. The excellent energy efficiency can be explained by the non-equilibrium character of the plasma, in which the electrons mainly activate the gas molecules, and by the important role of the vibrational kinetics of CO2. The results demonstrate that a gliding arc plasmatron is very promising for DRM. |
||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language ![]() |
Wos | 000413565100012 | Publication Date | 2017-10-02 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1864-5631 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 7.226 | Times cited | 23 | Open Access | OpenAccess |
Notes | Fonds Wetenschappelijk Onderzoek, G.0383.16N ; Federaal Wetenschapsbeleid; | Approved | Most recent IF: 7.226 | ||
Call Number | PLASMANT @ plasmant @c:irua:146665 | Serial | 4759 | ||
Permanent link to this record | |||||
Author | Momot, A.; Amini, M.N.; Reekmans, G.; Lamoen, D.; Partoens, B.; Slocombe, D.R.; Elen, K.; Adriaensens, P.; Hardy, A.; Van Bael, M.K. | ||||
Title | A novel explanation for the increased conductivity in annealed Al-doped ZnO: an insight into migration of aluminum and displacement of zinc | Type | A1 Journal article | ||
Year | 2017 | Publication | Physical chemistry, chemical physics | Abbreviated Journal | Phys Chem Chem Phys |
Volume | 19 | Issue | 40 | Pages | 27866-27877 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | A combined experimental and first-principles study is performed to study the origin of conductivity in ZnO:Al nanoparticles synthesized under controlled conditions via a reflux route using benzylamine as a solvent. The experimental characterization of the samples by Raman, nuclear magnetic resonance (NMR) and conductivity measurements indicates that upon annealing in nitrogen, the Al atoms at interstitial positions migrate to the substitutional positions, creating at the same time Zn interstitials. We provide evidence for the fact that the formed complex of AlZn and Zni corresponds to the origin of the Knight shifted peak (KS) we observe in 27Al NMR. As far as we know, the role of this complex has not been discussed in the literature to date. However, our first-principles calculations show that such a complex is indeed energetically favoured over the isolated Al interstitial positions. In our calculations we also address the charge state of the Al interstitials. Further, Zn interstitials can migrate from Al_Zn and possibly also form Zn clusters, leading to the observed increased conductivity. |
||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language ![]() |
Wos | 000413290500073 | Publication Date | 2017-10-09 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1463-9076 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.123 | Times cited | 26 | Open Access | OpenAccess |
Notes | We want to thank the Interuniversity Attraction Poles Programme (P7/05) initiated by the Belgian Science Policy Office (BELSPO) for the financial support. We also acknowledge the Research Foundation Flanders (FWO-Vlaanderen) for support via the MULTIMAR WOG project and under project No. G018914. The computational parts were carried out using the HPC infrastructure at the University of Antwerp (CalcUA), a division of the Flemish Supercomputer Center VSC, supported financially by the Hercules foundation and the Flemish Government (EWI Department). | Approved | Most recent IF: 4.123 | ||
Call Number | EMAT @ emat @c:irua:146878 | Serial | 4760 | ||
Permanent link to this record | |||||
Author | Trenchev, G.; Kolev, S.; Wang, W.; Ramakers, M.; Bogaerts, A. | ||||
Title | CO2Conversion in a Gliding Arc Plasmatron: Multidimensional Modeling for Improved Efficiency | Type | A1 Journal article | ||
Year | 2017 | Publication | The journal of physical chemistry: C : nanomaterials and interfaces | Abbreviated Journal | J Phys Chem C |
Volume | 121 | Issue | 44 | Pages | 24470-24479 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | The gliding arc plasmatron (GAP) is a highly efficient atmospheric plasma source, which is very promising for CO2 conversion applications. To understand its operation principles and to improve its application, we present here comprehensive modeling results, obtained by means of computational fluid dynamics simulations and plasma modeling. Because of the complexity of the CO2 plasma, a full 3D plasma model would be computationally impractical. Therefore, we combine a 3D turbulent gas flow model with a 2D plasma and gas heating model in order to calculate the plasma parameters and CO2 conversion characteristics. In addition, a complete 3D gas flow and plasma model with simplified argon chemistry is used to evaluate the gliding arc evolution in space and time. The calculated values are compared with experimental data from literature as much as possible in order to validate the model. The insights obtained in this study are very helpful for improving the application of CO2 conversion, as they allow us to identify the limiting factors in the performance, based on which solutions can be provided on how to further improve the capabilities of CO2 conversion in the GAP. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language ![]() |
Wos | 000415140400014 | Publication Date | 2017-11-09 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1932-7447 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.536 | Times cited | Open Access | OpenAccess | |
Notes | H2020 Marie Sklodowska-Curie Actions, 657304 ; Fonds Wetenschappelijk Onderzoek, 11U5316N G038316N ; | Approved | Most recent IF: 4.536 | ||
Call Number | PLASMANT @ plasmant @c:irua:147193 | Serial | 4765 | ||
Permanent link to this record | |||||
Author | Shetty, S.; Sinha, S.K.; Ahmad, R.; Singh, A.K.; Van Tendeloo, G.; Ravishankar, N. | ||||
Title | Existence of Ti2+States on the Surface of Heavily Reduced SrTiO3Nanocubes | Type | A1 Journal article | ||
Year | 2017 | Publication | Chemistry of materials | Abbreviated Journal | Chem Mater |
Volume | Issue | Pages | acs.chemmater.7b04113 | ||
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Using advanced electron microscopy, we demonstrate the presence of Ti2+ on the 001 surfaces of heavily reduced strontium titanate nanocubes. While high-angle annular dark field images show a clear difference between the surfaces of the unreduced and reduced samples, electron energy loss spectroscopy detects the presence of Ti2+ on the surface of the reduced cubes. Conventional reduction only leads to the formation of Ti3+ and involves the use of high temperatures. In our case, reduction is achieved at relatively lower temperatures in the solid state using sodium borohydride as the reducing agent. Our findings provide insights into the optical properties of the samples and provide a convenient method to produce highly reduced surfaces that could demonstrate a range of exotic physical phenomena | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language ![]() |
Wos | 000418206600005 | Publication Date | 2017-11-17 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0897-4756 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 9.466 | Times cited | 8 | Open Access | OpenAccess |
Notes | We thank Advanced Facility for Microscopy and Microanalysis (AFMM), IISc, Bangalore for providing the TEM facility. We also thank MNCF, CeNSE, IISc for providing the XPS and FT-IR facilities. We acknowledge the help from Prof. Anshu Pandey for providing the PL facility and Mr. Ashutosh Gupta for the help with measurements. SS and NR thank DST for providing the financial support. RA and AKS acknowledge Super Computing Education and Research Center (SERC) and Materials Research Center (MRC), at IISc for providing required computational facilities. RA acknowledges the financial support from INSPIRE fellowship, AORC.Science and Engineering Research Board; Federaal Wetenschapsbeleid; Department of Science and Technology, Ministry of Science and Technology; | Approved | Most recent IF: 9.466 | ||
Call Number | UA @ lucian @c:irua:147191 | Serial | 4767 | ||
Permanent link to this record | |||||
Author | Morozov, V.A.; Batuk, D.; Batuk, M.; Basovich, O.M.; Khaikina, E.G.; Deyneko, D.V.; Lazoryak, B.I.; Leonidov, I.I.; Abakumov, A.M.; Hadermann, J. | ||||
Title | Luminescence Property Upgrading via the Structure and Cation Changing in AgxEu(2–x)/3WO4and AgxGd(2–x)/3–0.3Eu0.3WO4 | Type | A1 Journal article | ||
Year | 2017 | Publication | Chemistry of materials | Abbreviated Journal | Chem Mater |
Volume | 29 | Issue | 20 | Pages | 8811-8823 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | The creation and ordering of A-cation vacancies and the effect of cation substitutions in the scheelite-type framework are investigated as a factor for controlling the scheelite-type structure and luminescence properties. AgxEu3+(2−x)/3□(1−2x)/3WO4 and AgxGd(2−x)/3−0.3Eu3+0.3□(1−2x)/3WO4 (x = 0.5−0) scheelite-type phases were synthesized by a solid state method, and their structures were investigated using a combination of transmission electron microscopy techniques and powder synchrotron X-ray diffraction. Transmission electron microscopy also revealed the (3 + 1)D incommensurately modulated character of AgxEu3+(2−x)/3□(1−2x)/3WO4 (x = 0.286, 0.2) phases. The crystal structures of the scheelite-based AgxEu3+(2−x)/3□(1−2x)/3WO4 (x = 0.5, 0.286, 0.2) red phosphors have been refined from high resolution synchrotron powder X-ray diffraction data. The luminescence properties of all phases under near-ultraviolet (n-UV) light have been investigated. The excitation spectra of AgxEu3+(2−x)/3□(1−2x)/3WO4 (x = 0.5, 0.286,0.2) phosphors show the strongest absorption at 395 nm, which matches well with the commercially available n-UV-emitting GaN-based LED chip. The excitation spectra of the Eu2/3□1/3WO4 and Gd0.367Eu0.30□1/3WO4 phases exhibit the highest contribution of the charge transfer band at 250 nm and thus the most efficient energy transfer mechanism between the host and the luminescent ion as compared to direct excitation. The emission spectra of all samples indicate an intense red emission due to the 5D0 → 7F2 transition of Eu3+. Concentration dependence of the 5D0 → 7F2 emission for AgxEu(2−x)/3□(1−2x)/3WO4 samples differs from the same dependence for the earlier studied NaxEu3+(2−x)/3□(1−2x)/3MoO4 (0 ≤ x ≤ 0.5) phases. The intensity of the 5D0 → 7F2 emission is reduced almost 7 times with decreasing x from 0.5 to 0, but it practically does not change in the range from x = 0.286 to x = 0.200. The emission spectra of Gd-containing samples show a completely different trend as compared to only Eu-containing samples. The Eu3+ emission under excitation of Eu3+(5L6) level (λex = 395 nm) increases more than 2.5 times with the increasing Gd3+ concentration from 0.2 (x = 0.5) to 0.3 (x = 0.2) in the AgxGd(2−x)/3−0.3Eu3+0.3□(1−2x)/3WO4, after which it remains almost constant for higher Gd3+ concentrations. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language ![]() |
Wos | 000413884900028 | Publication Date | 2017-10-24 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0897-4756 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 9.466 | Times cited | 7 | Open Access | Not_Open_Access |
Notes | This research was supported by FWO (project G039211N), Flanders Research Foundation. V.A.M. is grateful for financial support of the Russian Foundation for Basic Research (Grant 15-03-07741). E.G.K. and O.M.B. are grateful for financial support of the Russian Foundation for Basic Research (Grants 13-03-01020 and 16-03-00510). D.V.D. is grateful for financial support of the Russian Foundation for Basic Research (Grant 16-33-00197) and the Foundation of the President of the Russian Federation (Grant MK-7926.2016.5.). We are grateful to the ESRF for granting the beamtime. Experimental support of Andy Fitch at the ID31 beamline of ESRF is kindly acknowledged. | Approved | Most recent IF: 9.466 | ||
Call Number | EMAT @ emat @c:irua:147241 | Serial | 4768 | ||
Permanent link to this record | |||||
Author | Kus, M.; Altantzis, T.; Vercauteren, S.; Caretti, I.; Leenaerts, O.; Batenburg, K.J.; Mertens, M.; Meynen, V.; Partoens, B.; Van Doorslaer, S.; Bals, S.; Cool, P. | ||||
Title | Mechanistic Insight into the Photocatalytic Working of Fluorinated Anatase {001} Nanosheets | Type | A1 Journal article | ||
Year | 2017 | Publication | The journal of physical chemistry: C : nanomaterials and interfaces | Abbreviated Journal | J Phys Chem C |
Volume | 121 | Issue | 121 | Pages | 26275-26286 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT); Laboratory of adsorption and catalysis (LADCA) | ||||
Abstract | Anatase nanosheets with exposed {001} facets have gained increasing interest for photocatalytic applications. To fully understand the structure-to-activity relation, combined experimental and computational methods have been exploited. Anatase nanosheets were prepared under hydrothermal conditions in the presence of fluorine ions. High resolution scanning transmission electron microscopy was used to fully characterize the synthesized material, confirming the TiO2 nanosheet morphology. Moreover, the surface structure and composition of a single nanosheet could be determined by annular bright-field scanning transmission electron microscopy (ABF-STEM) and STEM electron energy loss spectroscopy (STEM-EELS). The photocatalytic activity was tested for the decomposition of organic dyes rhodamine 6G and methyl orange and compared to a reference TiO2 anatase sample. The anatase nanosheets with exposed {001} facets revealed a significantly lower photocatalytic activity compared to the reference. In order to understand the mechanism for the catalytic performance, and to investigate the role of the presence of F−, light-induced electron paramagnetic resonance (EPR) experiments were performed. The EPR results are in agreement with TEM, proving the presence of Ti3+ species close to the surface of the sample and allowing the analysis of the photoinduced formation of paramagnetic species. Further, ab initio calculations of the anisotropic effective mass of electrons and electron holes in anatase show a very high effective mass of electrons in the [001] direction, having a negative impact on the mobility of electrons toward the {001} surface and thus the photocatalysis. Finally, motivated by the experimental results that indicate the presence of fluorine atoms at the surface, we performed ab initio calculations to determine the position of the band edges in anatase slabs with different terminations of the {001} surface. The presence of fluorine atoms near the surface is shown to strongly shift down the band edges, which indicates another reason why it can be expected that the prepared samples with a large amount of {001} surface, but with fluorine atoms near the surface, show only a low photocatalytic activity. |
||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language ![]() |
Wos | 000417228500017 | Publication Date | 2017-11-30 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1932-7447 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.536 | Times cited | 20 | Open Access | OpenAccess |
Notes | The authors acknowledge the University of Antwerp for financial support in the frame of a GOA project. S.B. acknowledges funding from the European Research Council under the Seventh Framework Program (FP7), ERC Grant No. 335078 COLOURATOM. S.V.D. and V.M. acknowledge funding from the Fund for Scientific Research-Flanders (G.0687.13). T.A. acknowledges financial support from the Research Foundation Flanders (FWO, Belgium) through a postdoctoral grant. (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); saraecas; ECAS_Sara; | Approved | Most recent IF: 4.536 | ||
Call Number | EMAT @ emat @c:irua:147240UA @ admin @ c:irua:147240 | Serial | 4771 | ||
Permanent link to this record | |||||
Author | Jacquet, Q.; Perez, A.; Batuk, D.; Van Tendeloo, G.; Rousse, G.; Tarascon, J.-M. | ||||
Title | The Li3RuyNb1-yO4 (0 ≤y≤ 1) System: Structural Diversity and Li Insertion and Extraction Capabilities | Type | A1 Journal article | ||
Year | 2017 | Publication | Chemistry of materials | Abbreviated Journal | Chem Mater |
Volume | 29 | Issue | 12 | Pages | 5331-5343 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Searching for novel high-capacity electrode materials combining cationic and anionic redox processes is an ever-growing activity within the field of Li-ion batteries. In this respect, we report on the exploration of the Li3RuyNb1-yO4 (O <= y <= 1) system with an O/M ratio of 4 to maximize the number of oxygen lone pairs, responsible for the anionic redox. We show that this system presents a very rich crystal chemistry with the existence of four structural types, which derive from the rocksalt structure but differ in their cationic arrangement, creating either zigzag, helical, jagged chains or clusters. From an electrochemical standpoint, these compounds are active on reduction via a classical cationic insertion process. The oxidation process is more complex, because of the instability of the delithiated phase. Our results promote the use of the rich Li3MO4 family as a viable platform for a better understanding of the relationships between structure and anionic redox activity. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language ![]() |
Wos | 000404493100036 | Publication Date | 2017-06-27 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0897-4756 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 9.466 | Times cited | 17 | Open Access | Not_Open_Access |
Notes | The authors thank Paul Pearce, Alexis Grimaud, Matthieu Saubanere, and Marie-Liesse Doublet for fruitful discussions, Vivian Nassif for her help in neutron diffraction experiment at the D1B diffractometer at ILL, and Dominique Foix for XPS analysis. Use of the Advanced Photon Source at Argonne National Laboratory was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357. Q.J. thanks the ANR “Deli-Redox” for Ph.D. funding. J.-M.T. and D.B. acknowledge funding from the European Research Council (ERC) (FP/2014)/ERC Grant -Project 670116-ARPEMA. | Approved | Most recent IF: 9.466 | ||
Call Number | EMAT @ emat @c:irua:147506 | Serial | 4776 | ||
Permanent link to this record | |||||
Author | Niu, H.; Pitcher, M.J.; Corkett, A.J.; Ling, S.; Mandal, P.; Zanella, M.; Dawson, K.; Stamenov, P.; Batuk, D.; Abakumov, A.M.; Bull, C.L.; Smith, R.I.; Murray, C.A.; Day, S.J.; Slater, B.; Cora, F.; Claridge, J.B.; Rosseinsky, M.J. | ||||
Title | Room Temperature Magnetically Ordered Polar Corundum GaFeO3 Displaying Magnetoelectric Coupling | Type | A1 Journal article | ||
Year | 2017 | Publication | Journal of the American Chemical Society | Abbreviated Journal | J Am Chem Soc |
Volume | 139 | Issue | 4 | Pages | 1520-1531 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | The polar corundum structure type offers a route to new room temperature multiferroic materials, as the partial LiNbO3-type cation ordering that breaks inversion symmetry may be combined with long-range magnetic ordering of high spin d(5) cations above room temperature in the AFeO(3) system. We report the synthesis of a polar corundum GaFeO3 by a high-pressure, high-temperature route and demonstrate that its polarity arises from partial LiNbO3 -type cation ordering by complementary use of neutron, X-ray, and electron diffraction methods. In situ neutron diffraction shows that the polar corundum forms directly from AlFeO3-type GaFeO3 under the synthesis conditions. The A(3+)/Fe3+ cations are shown to be more ordered in polar corundum GaFeO3 than in isostructural ScFeO3. This is explained by DFT calculations which indicate that the extent of ordering is dependent on the configurational entropy available to each system at the very different synthesis temperatures required to form their corundum structures. Polar corundum GaFeO3 exhibits weak ferromagnetism at room temperature that arises from its Fe2O3-like magnetic ordering, which persists to a temperature of 408 K. We demonstrate that the polarity and magnetization are coupled in this system with a measured linear magnetoelectric coupling coefficient of 0.057 ps/m. Such coupling is a prerequisite for potential applications of polar corundum materials in multiferroic/magnetoelectric devices. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language ![]() |
Wos | 000393355600034 | Publication Date | 2016-12-25 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0002-7863 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 13.858 | Times cited | 12 | Open Access | OpenAccess |
Notes | This work was funded by the EPSRC under EP/N004884. We thank the STFC for provision of beam time at ISIS and Diamond Light Source. We thank the Materials Chemistry Consortium (EPSRC, EP/L000202) for access to computer time on the ARCHER UK National Supercomputing Service (http://www.archer.ac.uk). A.M.A. is grateful to the Russian Science Foundation (Grant 14-13-00680) for financial support. MJ.R is a Royal Society Research Professor. We wish to thank Dr. Ming Li (University of Nottingham, UK) for helpful discussion and advice. Original data is available at the University of Liverpool's DataCat repository at DOI: 10.17638/datacat.liverpool.ac.uk/235. The supporting crystallographic information file may also be obtained from FIZ Karlsruhe, 76344 Eggenstein-Leopoldshafen, Germany (e-mail: crysdata@fiz-karlsruhe.de), on quoting the deposition number CSD-432419. | Approved | Most recent IF: 13.858 | ||
Call Number | EMAT @ emat @c:irua:147507 | Serial | 4777 | ||
Permanent link to this record |