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Author | Wang, Z.; Zhang, Y.; Neyts, E.C.; Cao, X.; Zhang, X.; Jang, B.W.-L.; Liu, C.-jun | ||||
Title | Catalyst preparation with plasmas : how does it work? | Type | A1 Journal article | ||
Year | 2018 | Publication | ACS catalysis | Abbreviated Journal | Acs Catal |
Volume | 8 | Issue | 3 | Pages | 2093-2110 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Catalyst preparation with plasmas is increasingly attracting interest. A plasma is a partially ionized gas, consisting of electrons, ions, molecules, radicals, photons, and excited species, which are all active species for catalyst preparation and treatment. Under the influence of plasma, nucleation and crystal growth in catalyst preparation can be very different from those in the conventional thermal approach. Some thermodynamically unfavorable reactions can easily take place with plasmas. Compounds such as sulfides, nitrides, and phosphides that are produced under harsh conditions can be synthesized by plasma under mild conditions. Plasmas can produce catalysts with smaller particle sizes and controllable structure. Plasma is also a facile tool for reduction, oxidation, doping, etching, coating, alloy formation, surface treatment, and surface cleaning in a simple and direct way. A rapid and convenient plasma template removal has thus been established for zeolite synthesis. It can operate at room temperature and allows the catalyst preparation on temperature-sensitive supporting materials. Plasma is typically effective for the production of various catalysts on metallic substrates. In addition, plasma-prepared transition-metal catalysts show enhanced low-temperature activity with improved stability. This provides a useful model catalyst for further improvement of industrial catalysts. In this review, we aim to summarize the recent advances in catalyst preparation with plasmas. The present understanding of plasma-based catalyst preparation is discussed. The challenges and future development are addressed. | ||||
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Corporate Author | Thesis | ||||
Publisher | Amer chemical soc | Place of Publication | Washington | Editor | |
Language | Wos | 000426804100055 | Publication Date | 2018-01-29 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2155-5435 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 10.614 | Times cited | 81 | Open Access | Not_Open_Access |
Notes | Approved | Most recent IF: 10.614 | |||
Call Number | UA @ lucian @ c:irua:150880 | Serial | 4963 | ||
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Author | Theofanidis, S.A.; Galvita, V.V.; Poelman, H.; Dharanipragada, N.V.R.A.; Longo, A.; Meledina, M.; Van Tendeloo, G.; Detavernier, C.; Marin, G.B. | ||||
Title | Fe-containing magnesium aluminate support for stability and carbon control during methane reforming | Type | A1 Journal article | ||
Year | 2018 | Publication | ACS catalysis | Abbreviated Journal | Acs Catal |
Volume | 8 | Issue | 7 | Pages | 5983-5995 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | We report a MgFexAl2-xO4 synthetic spinel, where x varies from 0 to 0.26, as support for Ni-based catalysts, offering stability and carbon control under various conditions of methane reforming. By incorporation of Fe into a magnesium aluminate spine!, a support is created with redox functionality and high thermal stability, as concluded from temporal analysis of products (TAP) experiments and redox cycling, respectively. A diffusion coefficient of 3 x 10(-17) m(2) s(-1) was estimated for lattice oxygen at 993 K from TAP experiments. X-ray diffraction (XRD) and extended X-ray absorption fine structure (EXAFS) modeling identified that the incorporation of iron occurs as Fe3+ in the octahedral sites of the spinel lattice, replacing aluminum. Simulation of the X-ray absorption near edge structure (XANES) spectrum of the reduced support showed that 60 +/- 10% of iron was reduced from 3+ to 2+ at 1073 K, while there was no formation of metallic iron. A series of Ni/MgFexAl2-xO4 catalysts, where x varies from 0 to 0.26, was synthesized and reduced, yielding a supported Ni-Fe alloy. The evolution of the catalyst structure during H-2 temperature-programmed reduction (TPR) and CO2 temperature-programmed oxidation (TPO) was examined using time-resolved in situ XRD and XANES. During reforming, iron in both the support and alloy keeps control of carbon accumulation, as confirmed by O-2-TPO on the spent catalysts. By fine tuning the amount of Fe in MgFexAl2-xO4, a supported alloy was obtained with a Ni/Fe molar ratio of similar to 10, which was active for reforming and stable. By comparison of the performance of Ni-based catalysts with Fe either incorporated into or deposited onto the support, the location of Fe within the support proved crucial for the stability and carbon mitigation under reforming conditions. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000438475100034 | Publication Date | 2018-05-22 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2155-5435 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 10.614 | Times cited | 18 | Open Access | OpenAccess |
Notes | ; This work was supported by the FAST industrialization by Catalyst Research and Development (FASTCARD) project, which is a Large Scale Collaborative Project supported by the European Commission in the 7th Framework Programme (GA no 604277), the “Long Term Structural Methusalem Funding by the Flemish Government”, the Interuniversity Attraction Poles Programme, IAP7/5, Belgian State – Belgian Science Policy, and the Fund for Scientific Research Flanders (FWO-Vlaanderen) in supplying financing of travel costs and beam time at the DUBBLE beamline of the ESRF. The authors acknowledge the assistance from the DUBBLE (ESRF, XAS campaign 26-01-1048) and ROCK staff (SOLEIL, proposal 201502561). The authors equally acknowledge support from a public grant overseen by the French National Research Agency (ANR) as part of the “Investissements d'Avenir” program (reference: ANR-10-EQPX-45) for the ROCK beamline and from Lukas Buelens and Rakesh Batchu (Laboratory for Chemical Technology, Ghent University) for the STEM measurements and TAP experiments, respectively. ; | Approved | Most recent IF: 10.614 | ||
Call Number | UA @ lucian @ c:irua:153178 | Serial | 5102 | ||
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Author | Benito, P.; de Nolf, W.; Nuyts, G.; Janssens, K.; et al. | ||||
Title | Role of coating-metallic support interaction in the properties of electrosynthesized Rh-based structured catalysts | Type | A1 Journal article | ||
Year | 2014 | Publication | ACS catalysis | Abbreviated Journal | Acs Catal |
Volume | 4 | Issue | 10 | Pages | 3779-3790 |
Keywords | A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) | ||||
Abstract | Rh-structured catalysts for the catalytic partial oxidation of CH4 to syngas were prepared by electrosynthesis of Rh-containing hydrotalcite-type (HT) compounds on FeCrAlloy foams followed by calcination at 900 degrees C. During the calcination the simultaneous decomposition of the layered HT structure and formation of the protective FeCrAlloy outer shell in alumina occurred. Here, we studied the role of the coating-metallic support interaction in the properties of the catalysts after calcination, H-2 reduction, and catalytic tests, by a combination of electron (FEG-SEM/EDS) and synchrotron X-ray (XRF/XRPD and XRF/XANES) microscopic techniques. The characterization of crystalline phases in the metallic support and coating and distribution of Rh active species was carried out on several samples prepared by modifying the Rh content in the electrolytic solution (Rh/Mg/Al = 11.0/70.0/19.0, 5.0/70.0/25.0, 0/70.0/30.0 atomic ratio). A sample was also prepared with no aluminum in the electrolytic solution (Rh/Mg/Al = 13.6/86.4/0.0 atomic ratio) and calcined at 550 and 900 degrees C. The interaction between the elements of the metallic support and the catalytic coating increased the film adhesion during the thermal treatment and catalytic tests and modified the catalyst crystalline phases. A chemical reaction between Al corning from the foam and Mg in the coating occurred during calcination at high temperature leading to the formation of spinel phases in which rhodium is solved, together with some Rh2O3 and Rh. The metallic support was oxidized forming the corundum scale and chromium oxides, moreover t-Al2O3 was identified. For the Rh11.0Mg70.0Al19.0 catalyst the inclusion of Rh in the spinel phase decreased its reducibility in the H-2 pretreatment. The reduction continued during catalytic tests by feeding diluted CH4/O-2/He gas mixtures, evidenced by the catalyst activation. While under concentrated gas mixtures the deactivation occurred, probably by oxidation. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000345735200053 | Publication Date | 2014-09-24 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2155-5435 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 10.614 | Times cited | 13 | Open Access | |
Notes | ; The authors thank the scientists who assisted during the conducted experiments: D. Grolimund and C. N. Borca for the mu XRF/XRPD experiments performed at MicroXAS Beamline of SLS, M. Janousch for the mu XRF/XANES experiments at Phoenix Beamline of the SLS, M. Salome for the mu XRE/XANES experiments at ID21 Beamline of the ESRF, and I. Guerra for the FEG-SEM/EDS experiments at Granada University. Thanks must go to Porvair for supplying FeCrAlloy foams. The financial support from the Ministero per l'Istruzione, l'Universita e la Ricerca (MIUR, Roma, I) is gratefully acknowledged. ; | Approved | Most recent IF: 10.614; 2014 IF: 9.312 | ||
Call Number | UA @ admin @ c:irua:122215 | Serial | 5820 | ||
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Author | Tang, Z.; Liu, P.; Cao, H.; Bals, S.; Heeres, H.J.; Pescarmona, P.P. | ||||
Title | Pr/ZrO2 prepared by atomic trapping : an efficient catalyst for the conversion of glycerol to lactic acid with concomitant transfer hydrogenation of cyclohexene | Type | A1 Journal article | ||
Year | 2019 | Publication | ACS catalysis | Abbreviated Journal | Acs Catal |
Volume | 9 | Issue | 9 | Pages | 9953-9963 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | A series of heterogeneous catalysts consisting of highly dispersed Pt nanoparticles supported on nanosized ZrO2 (20 to 60 nm) was synthesized and investigated for the one-pot transfer hydrogenation between glycerol and cyclohexene to produce lactic acid and cyclohexane, without any additional H-2. Different preparation methods were screened, by varying the calcination and reduction procedures with the purpose of optimizing the dispersion of Pt species (i.e., as single-atom sites or extra-fine Pt nanoparticles) on the ZrO2 support. The Pt/ZrO2 catalysts were characterized by means of transmission electron microscopy techniques (HAADF-STEM, TEM), elemental analysis (ICP-OES, EDX mapping), N-2-physisorption, H-2 temperature-programmed-reduction (H-2-TPR), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD). Based on this combination of techniques it was possible to correlate the temperature of the calcination and reduction treatments with the nature of the Pt species. The best catalyst consisted of subnanometer Pt clusters (<1 nm) and atomically dispersed Pt (as Pt2+ and Pt4+) on the ZrO2 support, which were converted into extra-fine Pt nanoparticles (average size = 1.4 nm) upon reduction. These nanoparticles acted as catalytic species for the transfer hydrogenation of glycerol with cyclohexene, which gave an unsurpassed 95% yield of lactic acid salt at 96% glycerol conversion (aqueous glycerol solution, NaOH as promoter, 160 degrees C, 4.5 h, at 20 bar N-2). This is the highest yield and selectivity of lactic acid (salt) reported in the literature so far. Reusability experiments showed a partial and gradual loss of activity of the Pt/ZrO2 catalyst, which was attributed to the experimentally observed aggregation of Pt nanoparticles. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000494549700025 | Publication Date | 2019-09-16 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2155-5435 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 10.614 | Times cited | 46 | Open Access | OpenAccess |
Notes | Zhenchen Tang acknowledges the financial support from the China Scholarship Council for his Ph.D. grant. All the authors are grateful for the technical support from Erwin Wilbers, Anne Appeldoorn, and Marcel de Vries, the TEM support from Dr. Marc Stuart, and the ICP-OES support from Johannes van der Velde. Pei Liu and Sara Bals acknowledge financial support from the European Commission under the Horizon 2020 Programme by means of grant agreement No. 731019 EUSMI. | Approved | Most recent IF: 10.614 | ||
Call Number | UA @ admin @ c:irua:164643 | Serial | 6326 | ||
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Author | Saveleva, V.A.; Wang, L.; Kasian, O.; Batuk, M.; Hadermann, J.; Gallet, J.-j.; Bournel, F.; Alonso-Vante, N.; Ozouf, G.; Beauger, C.; Mayrhofer, K.J.J.; Cherevko, S.; Gago, A.S.; Friedrich, K.A.; Zafeiratos, S.; Savinova, E.R. | ||||
Title | Insight into the Mechanisms of High Activity and Stability of Iridium Supported on Antimony-Doped Tin Oxide Aerogel for Anodes of Proton Exchange Membrane Water Electrolyzers | Type | A1 Journal article | ||
Year | 2020 | Publication | Acs Catalysis | Abbreviated Journal | Acs Catal |
Volume | 10 | Issue | 4 | Pages | 2508-2516 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | The use of high amounts of iridium in industrial proton exchange membrane water electrolysers (PEMWE) could hinder their widespread use for the decarbonisation of society with hydrogen. Non-thermally oxidised Ir nanoparticles supported on antimony-doped tin oxide (SnO2:Sb, ATO) aerogel allow decreasing the use of the precious metal by more than 70 %, while enhancing the electro-catalytic activity and stability. To date the origin of these benefits remains unknown. Here we present clear evidence on the mechanisms that lead to the enhancement of the electrochemical properties of the catalyst. Operando near ambient pressure X-ray photoelectron spectroscopy on membrane electrode assemblies reveals a low degree of Ir oxidation, attributed to the oxygen spill-over from Ir to SnO2:Sb. Furthermore, the formation of highly unstable Ir(III) species is mitigated, while the decrease of Ir dissolution in Ir/SnO2:Sb is confirmed by inductively coupled plasma mass spectrometry (ICP-MS). The mechanisms that lead to the high activity and stability of Ir catalyst supported on SnO2:Sb aerogel for PEMWE are thus unveiled. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000516887400011 | Publication Date | 2020-02-21 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2155-5435 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 12.9 | Times cited | Open Access | OpenAccess | |
Notes | The research leading to these results has received funding from the European Union’s Seventh Framework Program (FP7/2007-2013) for Fuel Cell and Hydrogen Joint Technology (FCH JU) Initiative under Grant No. 621237 (INSIDE). In addition, A.S.G. and C.B. thank the European Union’s Horizon 2020 research and innovation programme for funding the project PRETZEL under grant agreement No 779478 and it is supported by FCH JU. Solvay is acknowledged for providing Aquivion membrane and ionomer. | Approved | Most recent IF: 12.9; 2020 IF: 10.614 | ||
Call Number | EMAT @ emat @c:irua:167147 | Serial | 6341 | ||
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Author | Mehta, P.; Barboun, P.M.; Engelmann, Y.; Go, D.B.; Bogaerts, A.; Schneider, W.F.; Hicks, J.C. | ||||
Title | Plasma-Catalytic Ammonia Synthesis beyond the Equilibrium Limit | Type | A1 Journal article | ||
Year | 2020 | Publication | Acs Catalysis | Abbreviated Journal | Acs Catal |
Volume | 10 | Issue | 12 | Pages | 6726-6734 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | We explore the consequences of nonthermal plasma-activation on product yields in catalytic ammonia synthesis, a reaction that is equilibrium-limited at elevated temperatures. We employ a minimal microkinetic model that incorporates the influence of plasma-activation on N2 dissociation rates to predict NH3 yields into and across the equilibrium-limited regime. NH3 yields are predicted to exceed bulk thermodynamic equilibrium limits on materials that are thermal-rate-limited by N2 dissociation. In all cases, yields revert to bulk equilibrium at temperatures at which thermal reaction rates exceed plasma-activated ones. Beyond-equilibrium NH3 yields are observed in a packed bed dielectric barrier discharge reactor and exhibit sensitivity to catalytic material choice in a way consistent with model predictions. The approach and results highlight the opportunity to exploit synergies between nonthermal plasmas and catalysts to affect transformations at conditions inaccessible through thermal routes. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000543663800015 | Publication Date | 2020-06-19 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2155-5435 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 12.9 | Times cited | Open Access | ||
Notes | University of Notre Dame; Basic Energy Sciences, DE-SC-0016543 ; Air Force Office of Scientific Research, FA9550-18-1- 0157 ; This work was supported by the U.S. Department of Energy, Office of Science, Basic Energy Sciences, Sustainable Ammonia Synthesis Program, under Award DE-SC-0016543 and by the U.S. Air Force Office of Scientific Research, under Award FA9550-18-1-0157. P.M. acknowledges support through the Eilers Graduate Fellowship for Energy Related Research from the University of Notre Dame. Computational resources were provided by the Notre Dame Center for Research Computing. We thank the Notre Dame Energy Materials Characterization Facility and the Notre Dame Integrated Imaging Facility for the use of the X-ray diffractometer and the transmission electron microscope, respectively. | Approved | Most recent IF: 12.9; 2020 IF: 10.614 | ||
Call Number | PLASMANT @ plasmant @c:irua:170713 | Serial | 6405 | ||
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Author | Irtem, E.; Arenas Esteban, D.; Duarte, M.; Choukroun, D.; Lee, S.; Ibáñez, M.; Bals, S.; Breugelmans, T. | ||||
Title | Ligand-Mode Directed Selectivity in Cu–Ag Core–Shell Based Gas Diffusion Electrodes for CO2Electroreduction | Type | A1 Journal article | ||
Year | 2020 | Publication | Acs Catalysis | Abbreviated Journal | Acs Catal |
Volume | Issue | Pages | 13468-13478 | ||
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT) | ||||
Abstract | Bimetallic nanoparticles with tailored size and specific composition have shown promise as stable and selective catalysts for electrochemical reduction of CO2 (CO2R) in batch systems. Yet, limited effort was devoted to understand the effect of ligand coverage and postsynthesis treatments on CO2 reduction, especially under industrially applicable conditions, such as at high currents (>100 mA/cm2) using gas diffusion electrodes (GDE) and flow reactors. In this work, Cu–Ag core–shell nanoparticles (11 ± 2 nm) were prepared with three different surface modes: (i) capped with oleylamine, (ii) capped with monoisopropylamine, and (iii) surfactant free with a reducing borohydride agent; Cu–Ag (OAm), Cu–Ag (MIPA), and Cu–Ag (NaBH4), respectively. The ligand exchange and removal was evidenced by infrared spectroscopy (ATR-FTIR) analysis, whereas high-resolution scanning transmission electron microscopy (HAADF-STEM) showed their effect on the interparticle distance and nanoparticle rearrangement. Later on, we developed a process-on-substrate method to track these effects on CO2R. Cu–Ag (OAm) gave a lower on-set potential for hydrocarbon production, whereas Cu–Ag (MIPA) and Cu–Ag (NaBH4) promoted syngas production. The electrochemical impedance and surface area analysis on the well-controlled electrodes showed gradual increases in the electrical conductivity and active surface area after each surface treatment. We found that the increasing amount of the triple phase boundaries (the meeting point for the electron–electrolyte–CO2 reactant) affect the required electrode potential and eventually the C+2e̅/C2e̅ product ratio. This study highlights the importance of the electron transfer to those active sites affected by the capping agents—particularly on larger substrates that are crucial for their industrial application. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000592978900031 | Publication Date | 2020-11-04 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2155-5435 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 12.9 | Times cited | 23 | Open Access | OpenAccess |
Notes | The authors also acknowledge financial support from the University Research Fund (BOF-GOA-PS ID No. 33928). S.L. has received funding from the European Union’s Horizon 2020 research and innovation program under the Marie SkłodowskaCurie Grant Agreement No. 665385. | Approved | Most recent IF: 12.9; 2020 IF: 10.614 | ||
Call Number | EMAT @ emat @c:irua:173803 | Serial | 6432 | ||
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Author | Van Velthoven, N.; Henrion, M.; Dallenes, J.; Krajnc, A.; Bugaev, A.L.; Liu, P.; Bals, S.; Soldatov, A.; Mali, G.; De Vos, D.E. | ||||
Title | S,O-functionalized metal-organic frameworks as heterogeneous single-site catalysts for the oxidative alkenylation of arenes via C- H activation | Type | A1 Journal article | ||
Year | 2020 | Publication | Acs Catalysis | Abbreviated Journal | Acs Catal |
Volume | 10 | Issue | 9 | Pages | 5077-5085 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Heterogeneous single-site catalysts can combine the R precise active site design of organometallic complexes with the efficient recovery of solid catalysts. Based on recent progress on homogeneous thioether ligands for Pd-catalyzed C-H activation reactions, we here develop a scalable metal-organic framework-based heterogeneous single-site catalyst containing S,O-moieties that increase the catalytic activity of Pd(II) for the oxidative alkenylation of arenes. The structure of the Pd@MOF-808-L1 catalyst was characterized in detail via solid-state nuclear magnetic resonance spectroscopy, N-2 physisorption, and high-angle annular dark field scanning transmission electron microscopy, and the structure of the isolated palladium active sites could be identified by X-ray absorption spectroscopy. A turnover frequency (TOF) of 8.4 h(-1) was reached after 1 h of reaction time, which was 3 times higher than the TOF of standard Pd(OAc)(2), ranking Pd@MOF-808-L1 among the most active heterogeneous catalysts ever reported for the nondirected oxidative alkenylation of arenes. Finally, we showed that the single-site catalyst promotes the oxidative alkenylation of a broad range of electron-rich arenes, and the applicability of this heterogeneous system was demonstrated by the gram-scale synthesis of industrially relevant products. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000530090800026 | Publication Date | 2020-04-06 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2155-5435 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 12.9 | Times cited | 37 | Open Access | OpenAccess |
Notes | ; The research leading to these results has received funding from the NMBP-01-2016 Program of the European Union's Horizon 2020 Framework Program H2020/2014-2020/under grant agreement no [720996]. N.V.V. and D.E.D.V. thank the FWO for funding (1S32917N and G0F2320N). D.E.D.V. is grateful for KU Leuven's support in the frame of the CASAS Metusalem project and a C3 type project. A.K. and G.M. acknowledge the financial support from the Slovenian Research Agency (research core funding no. P1-0021 and project no. N1-0079). A.L.B and A.V.S. acknowledge Russian Science Foundation grant no. 20-43-01015 for financial support. We thank Alexander Trigub and Alexey Veligzhanin for their support during the beamtime at Kurchatov Institute. We are indebted to Elizaveta Kamyshova and Anna Pnevskaya for their valuable help during EXAFS measurements. P.L. and S.B. thank European Research Council for the ERC Consolidator Grant 815128, REALNANO. Kassem Amro and Guillaume Gracy from Sikemia are gratefully acknowledged for providing ; sygma | Approved | Most recent IF: 12.9; 2020 IF: 10.614 | ||
Call Number | UA @ admin @ c:irua:169530 | Serial | 6598 | ||
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Author | Yi, Y.; Wang, X.; Jafarzadeh, A.; Wang, L.; Liu, P.; He, B.; Yan, J.; Zhang, R.; Zhang, H.; Liu, X.; Guo, H.; Neyts, E.C.; Bogaerts, A. | ||||
Title | Plasma-Catalytic Ammonia Reforming of Methane over Cu-Based Catalysts for the Production of HCN and H2at Reduced Temperature | Type | A1 Journal article | ||
Year | 2021 | Publication | Acs Catalysis | Abbreviated Journal | Acs Catal |
Volume | 11 | Issue | 3 | Pages | 1765-1773 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Industrial production of HCN from NH3 and CH4 not only uses precious Pt or Pt−Rh catalysts but also requires extremely high temperatures (∼1600 K). From an energetic, operational, and safety perspective, a drastic decrease in temperature is highly desirable. Here, we report ammonia reforming of methane for the production of HCN and H2 at 673 K by the combination of CH4/NH3 plasma and a supported Cu/silicalite-1 catalyst. 30% CH4 conversion has been achieved with 79% HCN selectivity. Catalyst characterization and plasma diagnostics reveal that the excellent reaction performance is attributed to metallic Cu active sites. In addition, we propose a possible reaction pathway, viz. E-R reactions with N, NH, NH2, and CH radicals produced in the plasma, for the production of HCN, based on density functional theory calculations. Importantly, the Cu/silicalite-1 catalyst costs less than 5% of the commercial Pt mesh catalyst. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000618540300057 | Publication Date | 2021-02-05 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2155-5435 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 10.614 | Times cited | Open Access | OpenAccess | |
Notes | Universiteit Antwerpen, 32249 ; China Postdoctoral Science Foundation, 2015M580220 2016T90217 ; PetroChina Innovation Foundation, 2018D-5007-0501 ; National Natural Science Foundation of China, 21503032 ; We acknowledge financial support from the National Natural Science Foundation of China [21503032], the China Postdoctoral Science Foundation [grant numbers 2015M580220 and 2016T90217, 2016], the PetroChina Innovation Foundation [2018D-5007-0501], and the TOP research project of the Research Fund of the University of Antwerp [grant ID 32249]. | Approved | Most recent IF: 10.614 | ||
Call Number | PLASMANT @ plasmant @c:irua:175880 | Serial | 6675 | ||
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Author | Coeck, R.; Meeprasert, J.; Li, G.; Altantzis, T.; Bals, S.; Pidko, E.A.; De Vos, D.E. | ||||
Title | Gold and silver-catalyzed reductive amination of aromatic carboxylic acids to benzylic amines | Type | A1 Journal article | ||
Year | 2021 | Publication | Acs Catalysis | Abbreviated Journal | Acs Catal |
Volume | 11 | Issue | 13 | Pages | 7672-7684 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT) | ||||
Abstract | The reductive amination of benzoic acid and its derivatives would be an effective addition to current synthesis methods for benzylamine. However, with current technology it is very difficult to keep the aromaticity intact when starting from benzoic acid, and salt wastes are often generated in the process. Here, we report a heterogeneous catalytic system for such a reductive amination, requiring solely H-2 and NH3 as the reactants. The Ag/TiO2 or Au/TiO2 catalysts can be used multiple times, and very little noble metal is required, only 0.025 mol % Au. The catalysts are bifunctional: the support catalyzes the dehydration of both the ammonium carboxylate to the amide and of the amide to the nitrile, while the sites at the metal-support interface promote the hydrogenation of the in situ generated nitrile. Yields of up to 92% benzylamine were obtained. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000670659900005 | Publication Date | 2021-06-10 | |
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Series Volume | Series Issue | Edition | |||
ISSN | 2155-5435 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 10.614 | Times cited | 16 | Open Access | OpenAccess |
Notes | R.C. thanks the FWO for his SB PhD fellowship. D.E.D.V. acknowledges FWO for research project funding, as well as KU Leuven for funding in the Metusalem program Casas. S.B. acknowledges support from the European Research Council (ERC Consolidator grant #815128 REALNANO). T.A. acknowledges funding from the University of Antwerp Research fund (BOF). E.A.P. acknowledges the support from the European Research Council (ERC Consolidator grant #725686 DeliCAT). J.M. acknowledges financial support through the Royal Thai Government Scholarship. DFT calculations on SURFsara supercomputer facilities were performed with support from the Netherlands Organization for Scientific Research (NWO).; sygmaSB | Approved | Most recent IF: 10.614 | ||
Call Number | UA @ admin @ c:irua:179851 | Serial | 6840 | ||
Permanent link to this record | |||||
Author | Nematollahi, P.; Barbiellini, B.; Bansil, A.; Lamoen, D.; Qingying, J.; Mukerjee, S.; Neyts, E.C. | ||||
Title | Identification of a Robust and Durable FeN4CxCatalyst for ORR in PEM Fuel Cells and the Role of the Fifth Ligand | Type | A1 Journal article | ||
Year | 2022 | Publication | ACS catalysis | Abbreviated Journal | Acs Catal |
Volume | Issue | Pages | 7541-7549 | ||
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Although recent studies have advanced the understanding of pyrolyzed Fe−N−C materials as oxygen reduction reaction (ORR) catalysts, the atomic and electronic structures of the active sites and their detailed reaction mechanisms still remain unknown. Here, based on first-principles density functional theory (DFT) computations, we discuss the electronic structures of three FeN4 catalytic centers with different local topologies of the surrounding C atoms with a focus on unraveling the mechanism of their ORR activity in acidic electrolytes. Our study brings back a forgotten, synthesized pyridinic Fe−N coordinate to the community’s attention, demonstrating that this catalyst can exhibit excellent activity for promoting direct four-electron ORR through the addition of a fifth ligand such as −NH2, −OH, and −SO4. We also identify sites with good stability properties through the combined use of our DFT calculations and Mössbauer spectroscopy data. |
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Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000823193100001 | Publication Date | 2022-06-10 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2155-5435 | ISBN | Additional Links | UA library record; WoS full record; WoS full record; WoS citing articles | |
Impact Factor | 12.9 | Times cited | Open Access | OpenAccess | |
Notes | Basic Energy Sciences, DE-FG02-07ER46352 ; Fonds Wetenschappelijk Onderzoek, 1261721N ; Opetus- ja Kulttuuriministeri?; Department of Energy, DE-EE0008416 ; | Approved | Most recent IF: 12.9 | ||
Call Number | EMAT @ emat @c:irua:189000 | Serial | 7073 | ||
Permanent link to this record | |||||
Author | Cui, Z.; Meng, S.; Yi, Y.; Jafarzadeh, A.; Li, S.; Neyts, E.C.; Hao, Y.; Li, L.; Zhang, X.; Wang, X.; Bogaerts, A. | ||||
Title | Plasma-catalytic methanol synthesis from CO₂ hydrogenation over a supported Cu cluster catalyst : insights into the reaction mechanism | Type | A1 Journal article | ||
Year | 2022 | Publication | Acs Catalysis | Abbreviated Journal | Acs Catal |
Volume | 12 | Issue | 2 | Pages | 1326-1337 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Plasma-catalytic CO, hydrogenation for methanol production is gaining increasing interest, but our understanding of its reaction mechanism remains primitive. We present a combined experimental/computational study on plasma-catalytic CO, hydrogenation to CH3OH over a size-selected Cu/gamma-Al2O3 catalyst. Our experiments demonstrate a synergistic effect between the Cu/gamma-Al2O3 catalyst and the CO2/H-2 plasma, achieving a CO2 conversion of 10% at 4 wt % Cu loading and a CH3OH selectivity near 50% further rising to 65% with H2O addition (for a H2O/CO2 ratio of 1). Furthermore, the energy consumption for CH3OH production was more than 20 times lower than with plasma only. We carried out density functional theory calculations over a Cu-13/gamma-Al2O3 model, which reveal that the interfacial sites of the Cu-13 cluster and gamma-Al2O3 support show a bifunctional effect: they not only activate the CO2 molecules but also strongly adsorb key intermediates to promote their hydrogenation further. Reactive plasma species can regulate the catalyst surface reactions via the Eley-Rideal (E-R) mechanism, which accelerates the hydrogenation process and promotes the generation of the key intermediates. H2O can promote the CH3OH desorption by competitive adsorption over the Cu-13/gamma-Al2O3 surface. This study provides new insights into CO2 hydrogenation through plasma catalysis, and it provides inspiration for the conversion of some other small molecules (CH4, N-2, CO, etc.) by plasma catalysis using supported-metal clusters. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000742735600001 | Publication Date | 2022-01-07 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2155-5435 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 12.9 | Times cited | Open Access | OpenAccess | |
Notes | Approved | Most recent IF: 12.9 | |||
Call Number | UA @ admin @ c:irua:186416 | Serial | 7192 | ||
Permanent link to this record | |||||
Author | Yang, S.; Liu, Z.; An, H.; Arnouts, S.; de Ruiter, J.; Rollier, F.; Bals, S.; Altantzis, T.; Figueiredo, M.C.; Filot, I.A.W.; Hensen, E.J.M.; Weckhuysen, B.M.; van der Stam, W. | ||||
Title | Near-unity electrochemical CO₂ to CO conversion over Sn-doped copper oxide nanoparticles | Type | A1 Journal article | ||
Year | 2022 | Publication | ACS catalysis | Abbreviated Journal | Acs Catal |
Volume | 12 | Issue | 24 | Pages | 15146-15156 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT) | ||||
Abstract | Bimetallic electrocatalysts have emerged as a viable strategy to tune the electrocatalytic CO2 reduction reaction (eCO2RR) for the selective production of valuable base chemicals and fuels. However, obtaining high product selectivity and catalyst stability remain challenging, which hinders the practical application of eCO2RR. In this work, it was found that a small doping concentration of tin (Sn) in copper oxide (CuO) has profound influence on the catalytic performance, boosting the Faradaic efficiency (FE) up to 98% for carbon monoxide (CO) at -0.75 V versus RHE, with prolonged stable performance (FE > 90%) for up to 15 h. Through a combination of ex situ and in situ characterization techniques, the in situ activation and reaction mechanism of the electrocatalyst at work was elucidated. In situ Raman spectroscopy measurements revealed that the binding energy of the crucial adsorbed *CO intermediate was lowered through Sn doping, thereby favoring gaseous CO desorption. This observation was confirmed by density functional theory, which further indicated that hydrogen adsorption and subsequent hydrogen evolution were hampered on the Sn-doped electrocatalysts, resulting in boosted CO formation. It was found that the pristine electrocatalysts consisted of CuO nanoparticles decorated with SnO2 domains, as characterized by ex situ high-resolution scanning transmission electron microscopy and X-ray photoelectron spectroscopy measurements. These pristine nanoparticles were subsequently in situ converted into a catalytically active bimetallic Sn-doped Cu phase. Our work sheds light on the intimate relationship between the bimetallic structure and catalytic behavior, resulting in stable and selective oxide-derived Sn-doped Cu electrocatalysts. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000900052400001 | Publication Date | 2022-11-28 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2155-5435 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 12.9 | Times cited | 16 | Open Access | OpenAccess |
Notes | B.M.W., S.Y., M.C.F., E.J.M.H., and W.v.d.S. acknowledge support from the Strategic UU-TU/e Alliance project ?Joint Centre for Chemergy Research?. S.B. acknowledges support from the European Research Council (ERC Consolidator grant #815128 REALNANO) . Z.L. acknowledges financial support of the China Scholarship Council and the Netherlands Organization for Scientific Research for access to computa-tional resources for carrying out the DFT calculations reported in this work. S.A. and T.A. acknowledge funding from theUniversity of Antwerp Research fund (BOF) . The authors also thank Dr. Jochem Wijten and Joris Janssens (Inorganic Chemistry and Catalysis, Utrecht University) for helpful technical support. Sander Deelen (Faculty of Science, Utrecht University) is acknowledged for the design of the in situ XRD cell. | Approved | Most recent IF: 12.9 | ||
Call Number | UA @ admin @ c:irua:192742 | Serial | 7325 | ||
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Author | Zhang, T.; Schilling, W.; Khan, S.U.; Ching, H.Y.V.; Lu, C.; Chen, J.; Jaworski, A.; Barcaro, G.; Monti, S.; De Wael, K.; Slabon, A.; Das, S. | ||||
Title | Atomic-level understanding for the enhanced generation of hydrogen peroxide by the introduction of an aryl amino group in polymeric carbon nitrides | Type | A1 Journal article | ||
Year | 2021 | Publication | Acs Catalysis | Abbreviated Journal | Acs Catal |
Volume | 11 | Issue | 22 | Pages | 14087-14101 |
Keywords | A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Organic synthesis (ORSY); Applied Electrochemistry & Catalysis (ELCAT); Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab) | ||||
Abstract | Heterogeneous catalysts are often & ldquo;black boxes & rdquo; due to the insufficient understanding of the detailed mechanisms at the catalytic sites. An atomic-level elucidation of the processes taking place in those regions is, thus, mandatory to produce robust and selective heterogeneous catalysts. We have improved the description of the whole reactive scenario for polymeric carbon nitrides (PCN) by combining atomic-level characterizations with magic-angle spinning (MAS) solid-state nuclear magnetic resonance (NMR) spectroscopy, classical reactive molecular dynamics (RMD) simulations, and quantum chemistry (QC) calculations. We disclose the structure & minus;property relationships of an ad hoc modified PCN by inserting an aryl amino group that turned out to be very efficient for the production of H2O2. The main advancement of this work is the development of a difluoromethylene-substituted aryl amino PCN to generate H2O2 at a rate of 2.0 mM & middot;h & minus;1 under the irradiation of household blue LEDs and the identification of possible active catalytic sites with the aid of 15N and 19F MAS solid-state NMR without using any expensive labeling reagent. RMD simulations and QC calculations confirm and further extend the experimental descriptions by revealing the role and locations of the identified functionalities, namely, NH linkers, & minus;NH2 terminal groups, and difluoromethylene units, reactants, and products. <comment>Superscript/Subscript Available</comment | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000758012900020 | Publication Date | 2021-11-05 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2155-5435 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 10.614 | Times cited | Open Access | Not_Open_Access | |
Notes | Approved | Most recent IF: 10.614 | |||
Call Number | UA @ admin @ c:irua:187276 | Serial | 7534 | ||
Permanent link to this record | |||||
Author | Bhatia, H.; Keshavarz, M.; Martin, C.; Van Gaal, L.; Zhang, Y.; de Coen, B.; Schrenker, N.J.; Valli, D.; Ottesen, M.; Bremholm, M.; Van de Vondel, J.; Bals, S.; Hofkens, J.; Debroye, E. | ||||
Title | Achieving High Moisture Tolerance in Pseudohalide Perovskite Nanocrystals for Light-Emitting Diode Application | Type | A1 Journal Article | ||
Year | 2023 | Publication | ACS Applied Optical Materials | Abbreviated Journal | ACS Appl. Opt. Mater. |
Volume | 1 | Issue | 6 | Pages | 1184-1191 |
Keywords | A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; | ||||
Abstract | The addition of potassium thiocyanate (KSCN) to the FAPbBr3 structure and subsequent post-treatment of nanocrystals (NCs) lead to high quantum confinement, resulting in a photoluminescent quantum yield (PLQY) approaching unity and microsecond decay times. This synergistic approach demonstrated exceptional stability under humid conditions, retaining 70% of the PLQY for over a month, while the untreated NCs degrade within 24 h. Additionally, the devices incorporating the post-treated NCs displayed 1.5% external quantum efficiency (EQE), a 5-fold improvement over untreated devices. These results provide promising opportunities for the use of perovskites in moisture-stable optoelectronics. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | Publication Date | 2023-06-23 | ||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2771-9855 | ISBN | Additional Links | UA library record | |
Impact Factor | Times cited | Open Access | OpenAccess | ||
Notes | Hercules Foundation, HER/11/14 ; European Commission; Ministerio de Ciencia e Innovaci?n, PID2021-128761OA-C22 ; European Regional Development Fund; Vlaamse regering, CASAS2 Meth/15/04 ; Fonds Wetenschappelijk Onderzoek, 1238622N 1514220N 1S45223N G.0B39.15 G.0B49.15 G098319N S002019N ZW15_09-GOH6316 ; Onderzoeksraad, KU Leuven, C14/19/079 db/21/006/bm iBOF-21-085 STG/21/010 ; Junta de Comunidades de Castilla-La Mancha, SBPLY/21/180501/000127 ; H2020 European Research Council, 642196 815128 ; | Approved | Most recent IF: NA | ||
Call Number | EMAT @ emat @c:irua:201011 | Serial | 8975 | ||
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Author | Asapu, R.; Claes, N.; Ciocarlan, R.-G.; Minjauw, M.; Detavernier, C.; Cool, P.; Bals, S.; Verbruggen, S.W. | ||||
Title | Electron Transfer and Near-Field Mechanisms in Plasmonic Gold-Nanoparticle-Modified TiO2Photocatalytic Systems | Type | A1 Journal article | ||
Year | 2019 | Publication | ACS applied nano materials | Abbreviated Journal | ACS Appl. Nano Mater. |
Volume | 2 | Issue | 2 | Pages | 4067-4074 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA); Sustainable Energy, Air and Water Technology (DuEL) | ||||
Abstract | The major mechanism responsible for plasmonic enhancement of titanium dioxide photocatalysis using gold nanoparticles is still under contention. This work introduces an experimental strategy to disentangle the significance of the charge transfer and near-field mechanisms in plasmonic photocatalysis. By controlling the thickness and conductive nature of a nanoparticle shell that acts as a spacer layer separating the plasmonic metal core from the TiO2 surface, field enhancement or charge transfer effects can be selectively repressed or evoked. Layer-by-layer and in situ polymerization methods are used to synthesize gold core–polymer shell nanoparticles with shell thickness control up to the sub-nanometer level. Detailed optical and electrical characterization supported by near-field simulation models corroborate the trends in photocatalytic activity of the different systems. This approach mainly points at an important contribution of the enhanced near field. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000477917700006 | Publication Date | 2019-05-31 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2574-0970 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | Times cited | 32 | Open Access | OpenAccess | |
Notes | This work was supported by Research Foundation Flanders (FWO). P.C. and R-G.C. acknowledge financial support from FWO (Project No. G038215N). N.C. and S.B. acknowledge financial support from the European Research Council (ERC Starting Grant No. 335078-COLOURATOM). | Approved | Most recent IF: NA | ||
Call Number | EMAT @ emat @UA @ admin @ c:irua:160579 | Serial | 5184 | ||
Permanent link to this record | |||||
Author | Crippa, F.; Rodriguez-Lorenzo, L.; Hua, X.; Goris, B.; Bals, S.; Garitaonandia, J.S.; Balog, S.; Burnand, D.; Hirt, A.M.; Haeni, L.; Lattuada, M.; Rothen-Rutishauser, B.; Petri-Fink, A. | ||||
Title | Phase transformation of superparamagnetic iron oxide nanoparticles via thermal annealing : implications for hyperthermia applications | Type | A1 Journal article | ||
Year | 2019 | Publication | ACS applied nano materials | Abbreviated Journal | |
Volume | 2 | Issue | 2 | Pages | 4462-4470 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Magnetic hyperthermia has the potential to play an important role in cancer therapy and its efficacy relies on the nanomaterials selected. Superparamagnetic iron oxide nanoparticles (SPIONs) are excellent candidates due to the ability of producing enough heat to kill tumor cells by thermal ablation. However, their heating properties depend strongly on crystalline structure and size, which may not be controlled and tuned during the synthetic process; therefore, a postprocessing is needed. We show how thermal annealing can be simultaneously coupled with ligand exchange to stabilize the SPIONs in polar solvents and to modify their crystal structure, which improves hyperthermia behavior. Using high-resolution transmission electron microscopy, X-ray diffraction, Mossbauer spectroscopy, vibrating sample magnetometry, and lock-in thermography, we systematically investigate the impact of size and ligand exchange procedure on crystallinity, their magnetism, and heating ability. We describe a valid and simple approach to optimize SPIONs for hyperthermia by carefully controlling the size, colloidal stability, and crystallinity. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000477917700048 | Publication Date | 2019-06-27 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | ||
Impact Factor | Times cited | 18 | Open Access | Not_Open_Access | |
Notes | ; This work was supported by the Swiss National Science Foundation through the National Center of Competence in Research Bio-Inspired Materials, the Adolphe Merkle Foundation, the University of Fribourg, and the European Society for Molecular Imaging (Grant E141200643). ; | Approved | Most recent IF: NA | ||
Call Number | UA @ admin @ c:irua:161927 | Serial | 5393 | ||
Permanent link to this record | |||||
Author | Mulder, J.T.; Kirkwood, N.; De Trizio, L.; Li, C.; Bals, S.; Manna, L.; Houtepen, A.J. | ||||
Title | Developing lattice matched ZnMgSe shells on InZnP quantum dots for phosphor applications | Type | A1 Journal article | ||
Year | 2020 | Publication | ACS applied nano materials | Abbreviated Journal | |
Volume | 3 | Issue | 4 | Pages | 3859-3867 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Indium phosphide quantum dots (QDs) have drawn attention as alternatives to cadmium- and lead-based QDs that are currently used as phosphors in lamps and displays. The main drawbacks of InP QDs are, in general, a lower photoluminescence quantum yield (PLQY), a decreased color purity, and poor chemical stability. In this research, we attempted to increase the PLQY and stability of indium phosphide QDs by developing lattice matched InP/MgSe core-shell nanoheterostructures. The choice of MgSe comes from the fact that, in theory, it has a near-perfect lattice match with InP, provided MgSe is grown in the zinc blende crystal structure, which can be achieved by alloying with zinc. To retain lattice matching, we used Zn in both the core and shell and we fabricated InZnP/ZnxMg1-xSe core/shell QDs. To identify the most suitable conditions for the shell growth, we first developed a synthesis route to ZnxMg1-xSe nanocrystals (NCs) wherein Mg is effectively incorporated. Our optimized procedure was employed for the successful growth of ZnxMg1-xSe shells around In(Zn)P QDs. The corresponding core/ shell systems exhibit PLQYs higher than those of the starting In(Zn)P QDs and, more importantly, a higher color purity upon increasing the Mg content. The results are discussed in the context of a reduced density of interface states upon using better lattice matched ZnxMg1-xSe shells. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000529206200076 | Publication Date | 2020-03-16 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2574-0970 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 5.9 | Times cited | 22 | Open Access | OpenAccess |
Notes | ; This project has received funding from the European Union's Horizon 2020 research and innovation programme under Grant Agreement No. 766900 (testing the large-scale limit of quantum mechanics). A.J.H. acknowledges support from the European Research Council Horizon 2020 ERC Grant Agreement No. 678004 (Doping on Demand). This research is supported by the Dutch Technology Foundation TTW, which is part of The Netherlands Organization for Scientific Research (NWO) and which is partly funded by Ministry of Economic Affairs. The authors thank Wiel Evers for performing the TEM imaging and the EDX analysis. The authors also thank Lea Pasquale and Mirko Prato for their help with performing and analyzing the XPS measurements and Filippo Drago for the ICP measurements. ; | Approved | Most recent IF: 5.9; 2020 IF: NA | ||
Call Number | UA @ admin @ c:irua:169563 | Serial | 6482 | ||
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Author | Borah, R.; Smets, J.; Ninakanti, R.; Tietze, M.L.; Ameloot, R.; Chigrin, D.N.; Bals, S.; Lenaerts, S.; Verbruggen, S.W. | ||||
Title | Self-assembled ligand-capped plasmonic Au nanoparticle films in the Kretschmann configuration for sensing of volatile organic compounds | Type | A1 Journal article | ||
Year | 2022 | Publication | ACS applied nano materials | Abbreviated Journal | |
Volume | 5 | Issue | 8 | Pages | acsanm.2c02524-12 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Sustainable Energy, Air and Water Technology (DuEL) | ||||
Abstract | Films of close-packed Au nanoparticles are coupled electrodynamically through their collective plasmon resonances. This collective optical response results in enhanced light–matter interactions, which can be exploited in various applications. Here, we demonstrate their application in sensing volatile organic compounds, using methanol as a test case. Ordered films over several cm2 were obtained by interfacial self-assembly of colloidal Au nanoparticles (∼10 nm diameter) through controlled evaporation of the solvent. Even though isolated nanoparticles of this size are inherently nonscattering, when arranged in a close-packed film the plasmonic coupling results in a strong reflectance and absorbance. The in situ tracking of vapor phase methanol concentration through UV–vis transmission measurements of the nanoparticle film is first demonstrated. Next, in situ ellipsometry of the self-assembled films in the Kretschmann (also known as ATR) configuration is shown to yield enhanced sensitivity, especially with phase difference measurements, Δ. Our study shows the excellent agreement between theoretical models of the spectral response of self-assembled films with experimental in situ sensing experiments. At the same time, the theoretical framework provides the basis for the interpretation of the various observed experimental trends. Combining periodic nanoparticle films with ellipsometry in the Kretschmann configuration is a promising strategy toward highly sensitive and selective plasmonic thin-film devices based on colloidal fabrication methods for volatile organic compound (VOC) sensing applications. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000834348300001 | Publication Date | 2022-07-27 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2574-0970 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 5.9 | Times cited | 11 | Open Access | OpenAccess |
Notes | R.B. acknowledges financial support from the University of Antwerp Special Research Fund (BOF) for a DOCPRO4 doctoral scholarship. J.S. acknowledges financial support from the Research Foundation Flanders (FWO) by a Ph.D. fellowship (11H8121N) . M.L.T. acknowledges financial support from the Research Foundation Flanders (FWO) by a senior postdoctoral fellowship (12ZK720N) . | Approved | Most recent IF: 5.9 | ||
Call Number | UA @ admin @ c:irua:189295 | Serial | 7095 | ||
Permanent link to this record | |||||
Author | Pacquets, L.; Van den Hoek, J.; Arenas Esteban, D.; Ciocarlan, R.-G.; Cool, P.; Baert, K.; Hauffman, T.; Daems, N.; Bals, S.; Breugelmans, T. | ||||
Title | Use of nanoscale carbon layers on Ag-based gas diffusion electrodes to promote CO production | Type | A1 Journal article | ||
Year | 2022 | Publication | ACS applied nano materials | Abbreviated Journal | |
Volume | 5 | Issue | 6 | Pages | 7723-7732 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA); Applied Electrochemistry & Catalysis (ELCAT) | ||||
Abstract | A promising strategy for the inhibition of the hydrogen evolution reaction along with the stabilization of the electrocatalyst in electrochemical CO2 reduction cells involves the application of a nanoscale amorphous carbon layer on top of the active catalyst layer in a gas diffusion electrode. Without modifying the chemical nature of the electrocatalyst itself, these amorphous carbon layers lead to the stabilization of the electrocatalyst, and a significant improvement with respect to the inhibition of the hydrogen evolution reaction was also obtained. The faradaic efficiencies of hydrogen could be reduced from 31.4 to 2.1% after 1 h of electrolysis with a 5 nm thick carbon layer. Furthermore, the impact of the carbon layer thickness (5–30 nm) on this inhibiting effect was investigated. We determined an optimal thickness of 15 nm where the hydrogen evolution reaction was inhibited and a decent stability was obtained. Next, a thickness of 15 nm was selected for durability measurements. Interestingly, these durability measurements revealed the beneficial impact of the carbon layer already after 6 h by suppressing the hydrogen evolution such that an increase of only 37.9% exists compared to 56.9% without the use of an additional carbon layer, which is an improvement of 150%. Since carbon is only applied afterward, it reveals its great potential in terms of electrocatalysis in general. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000818507900001 | Publication Date | 2022-05-19 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2574-0970 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 5.9 | Times cited | 3 | Open Access | OpenAccess |
Notes | L.P. was supported through a Ph.D. fellowship strategic basic research (1S56920N) of the Research Foundation-Flanders (FWO). S.B. acknowledges financial support from ERC Consolidator Grant Number 815128 REALNANO. This research was financed by the Research Council of the University of Antwerp (BOF-GOA 33928). P.C. and R.-G.C. acknowledge financial support by FWO Flanders (project no. G038215N). The authors recognize the contribution of S. Pourbabak and T. Derez for the assistance with the Ag and carbon coating, Indah Prihatiningtyas and Bart Van der Bruggen for the assistance with the contact angle measurements, Daniel Choukroun for the use of the in-house-made hybrid flow cell, and Stijn Van den Broeck for his assistance with the FIB measurements. | Approved | Most recent IF: 5.9 | ||
Call Number | UA @ admin @ c:irua:188887 | Serial | 7099 | ||
Permanent link to this record | |||||
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 | |
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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Publisher | Place of Publication | Editor | |||
Language | Wos | 001164609600001 | Publication Date | 2024-02-15 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2574-0970 | ISBN | Additional Links | UA library record; WoS full record | |
Impact Factor | 5.9 | Times cited | Open Access | ||
Notes | Approved | Most recent IF: 5.9; 2024 IF: NA | |||
Call Number | UA @ admin @ c:irua:204826 | Serial | 9164 | ||
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Author | Zeng, Y.-J.; Schouteden, K.; Amini, M.N.; Ruan, S.-C.; Lu, Y.-F.; Ye, Z.-Z.; Partoens, B.; Lamoen, D.; Van Haesendonck, C. | ||||
Title | Electronic band structures and native point defects of ultrafine ZnO nanocrystals | Type | A1 Journal article | ||
Year | 2015 | Publication | ACS applied materials and interfaces | Abbreviated Journal | Acs Appl Mater Inter |
Volume | 7 | Issue | 7 | Pages | 10617-10622 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) | ||||
Abstract | Ultrafine ZnO nanocrystals with a thickness down to 0.25 nm are grown by a metalorganic chemical vapor deposition method. Electronic band structures and native point defects of ZnO nanocrystals are studied by a combination of scanning tunneling microscopy/spectroscopy and first-principles density functional theory calculations. Below a critical thickness of nm ZnO adopts a graphitic-like structure and exhibits a wide band gap similar to its wurtzite counterpart. The hexagonal wurtzite structure, with a well-developed band gap evident from scanning tunneling spectroscopy, is established for a thickness starting from similar to 1.4 nm. With further increase of the thickness to 2 nm, V-O-V-Zn defect pairs are easily produced in ZnO nanocrystals due to the self-compensation effect in highly doped semiconductors. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000355055000063 | Publication Date | 2015-04-29 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1944-8244;1944-8252; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 7.504 | Times cited | 15 | Open Access | |
Notes | Hercules; EWI | Approved | Most recent IF: 7.504; 2015 IF: 6.723 | ||
Call Number | c:irua:126408 | Serial | 999 | ||
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Author | Buffière, M.; Brammertz, G.; Sahayaraj, S.; Batuk, M.; Khelifi, S.; Mangin, D.; El Mel, A.A.; Arzel, L.; Hadermann, J.; Meuris, M.; Poortmans, J.; | ||||
Title | KCN chemical etch for interface engineering in Cu2ZnSnSe4 solar cells | Type | A1 Journal article | ||
Year | 2015 | Publication | ACS applied materials and interfaces | Abbreviated Journal | Acs Appl Mater Inter |
Volume | 7 | Issue | 7 | Pages | 14690-14698 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | The removal of secondary phases from the surface of the kesterite crystals is one of the major challenges to improve the performances of Cu2ZnSn(S,Se)(4) (CZTSSe) thin film solar cells. In this Contribution, the KCN/KOH Chemical etching approach, originally developed for the removal of CuxSe phases in Cu(In,Ga)(S,Se)(2) thin films) is applied to CZTSe absorbers exhibiting various chemical compositions. Two distinct electrical behaviors were observed on CZTSe/CdS solar cells after treatment: (i) the improvement of the fill factor (FF) after 30 s of etching for the CZTSe absorbers showing initially a distortion of the electrical characteristic; (ii) the progressive degradation Of the FF after long treatment time for all Cu-poor CZTSe solar cell samples. The first effect can be attributed to the action of KCN on the absorber, that is found to clean the absorber free surface from most of the secondary phases surrounding the kesterite grains (e.g., Se-0, CuxSe, SnSex, SnO2, Cu2SnSe3 phases, excepting the ZnSe-based phases). The second observation was identified as a consequence of the preferential etching of Se, Sn, and Zn from the CZTSe surface by the KOH solution, combined with the modification of the alkali content of the absorber. The formation of a Cu-rich shell at the absorber/buffer layer interface, leading to the increase of the recombination rate at the interface, and the increase in the doping of the absorber layer after etching are found to be at the origin of the deterioration of the FF of the solar cells. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000358395200019 | Publication Date | 2015-06-03 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1944-8244;1944-8252; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 7.504 | Times cited | 34 | Open Access | |
Notes | Approved | Most recent IF: 7.504; 2015 IF: 6.723 | |||
Call Number | c:irua:127153 | Serial | 1755 | ||
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Author | Li, D.Y.; Zeng, Y.J.; Batuk, D.; Pereira, L.M.C.; Ye, Z.Z.; Fleischmann, C.; Menghini, M.; Nikitenko, S.; Hadermann, J.; Temst, K.; Vantomme, A.; Van Bael, M.J.; Locquet, J.P.; Van Haesendonck, C.; | ||||
Title | Relaxor ferroelectricity and magnetoelectric coupling in ZnOCo nanocomposite thin films : beyond multiferroic composites | Type | A1 Journal article | ||
Year | 2014 | Publication | ACS applied materials and interfaces | Abbreviated Journal | Acs Appl Mater Inter |
Volume | 6 | Issue | 7 | Pages | 4737-4742 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | ZnOCo nanocomposite thin films are synthesized by combination of pulsed laser deposition of ZnO and Co ion implantation. Both superparamagnetism and relaxor ferroelectricity as well as magnetoelectric coupling in the nanocomposites have been demonstrated. The unexpected relaxor ferroelectricity is believed to be the result of the local lattice distortion induced by the incorporation of the Co nanoparticles. Magnetoelectric coupling can be attributed to the interaction between the electric dipole moments and the magnetic moments, which are both induced by the incorporation of Co. The introduced ZnOCo nanocomposite thin films are different from conventional strain-mediated multiferroic composites. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000334572800018 | Publication Date | 2014-03-05 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1944-8244;1944-8252; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 7.504 | Times cited | 21 | Open Access | |
Notes | Approved | Most recent IF: 7.504; 2014 IF: 6.723 | |||
Call Number | UA @ lucian @ c:irua:117063 | Serial | 2864 | ||
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Author | Zeng, Y.-J.; Gauquelin, N.; Li, D.-Y.; Ruan, S.-C.; He, H.-P.; Egoavil, R.; Ye, Z.-Z.; Verbeeck, J.; Hadermann, J.; Van Bael, M.J.; Van Haesendonck, C. | ||||
Title | Co-Rich ZnCoO Nanoparticles Embedded in Wurtzite Zn1-xCoxO Thin Films: Possible Origin of Superconductivity | Type | A1 Journal article | ||
Year | 2015 | Publication | ACS applied materials and interfaces | Abbreviated Journal | Acs Appl Mater Inter |
Volume | 7 | Issue | 7 | Pages | 22166-22171 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Co-rich ZnCoO nanoparticles embedded in wurtzite Zn0.7Co0.3O thin films are grown by pulsed laser deposition on a Si substrate. Local superconductivity with an onset Tc at 5.9 K is demonstrated in the hybrid system. The unexpected superconductivity probably results from Co(3+) in the Co-rich ZnCoO nanoparticles or from the interface between the Co-rich nanoparticles and the Zn0.7Co0.3O matrix. | ||||
Address | Solid State Physics and Magnetism Section, KU Leuven , Celestijnenlaan 200 D, BE-3001 Leuven, Belgium | ||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | English | Wos | 000363001500007 | Publication Date | 2015-09-21 |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1944-8244;1944-8252; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 7.504 | Times cited | 13 | Open Access | |
Notes | This work has been supported by the Research Foundation − Flanders (FWO, Belgium) as well as by the Flemish Concerted Research Action program (BOF KU Leuven, GOA/14/007). N. G. and J. V. acknowledge funding from the European Research Council under the 7th Framework Program (FP7), ERC Starting Grant 278510 VORTEX. The Qu-Ant-EM microscope was partly funded by the Flemish Hercules Foundation. The work at Shenzhen University was supported by National Natural Science Foundation of China under Grant No. 61275144 and Natural Science Foundation of SZU. Y.-J. Z. acknowledges funding under grant No. SKL2015-12 from the State Key Laboratory of Silicon Materials; ECASJO_; | Approved | Most recent IF: 7.504; 2015 IF: 6.723 | ||
Call Number | c:irua:129195 c:irua:129195UA @ admin @ c:irua:129195 | Serial | 3949 | ||
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Author | Warwick, M.E.A.; Kaunisto, K.; Barreca, D.; Carraro, G.; Gasparotto, A.; Maccato, C.; Bontempi, E.; Sada, C.; Ruoko, T.P.; Turner, S.; Van Tendeloo, G.; | ||||
Title | Vapor phase processing of \alpha-Fe2O3 photoelectrodes for water splitting : an insight into the structure/property interplay | Type | A1 Journal article | ||
Year | 2015 | Publication | ACS applied materials and interfaces | Abbreviated Journal | Acs Appl Mater Inter |
Volume | 7 | Issue | 7 | Pages | 8667-8676 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Harvesting radiant energy to trigger water photoelectrolysis and produce clean hydrogen is receiving increasing attention in the search of alternative energy resources. In this regard, hematite (alpha-Fe2O3) nanostructures with controlled nano-organization have been fabricated and investigated for use as anodes in photoelectrochemical (PEC) cells. The target systems have been grown on conductive substrates by plasma enhanced-chemical vapor deposition (PE-CVD) and subjected to eventual ex situ annealing in air to further tailor their structure and properties. A detailed multitechnique approach has enabled to elucidate between system characteristics and the generated photocurrent. The present alpha-Fe2O3 systems are characterized by a high purity and hierarchical morphologies consisting of nanopyramids/organized dendrites, offering a high contact area with the electrolyte. PEC data reveal a dramatic response enhancement upon thermal treatment, related to a more efficient electron transfer. The reasons underlying such a phenomenon are elucidated and discussed by transient absorption spectroscopy (TAS) studies of photogenerated charge carrier kinetics, investigated on different time scales for the first time on PE-CVD Fe2O3 nanostructures. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000353931300037 | Publication Date | 2015-04-08 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1944-8244;1944-8252; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 7.504 | Times cited | 51 | Open Access | |
Notes | 246791 Countatoms; Fwo | Approved | Most recent IF: 7.504; 2015 IF: 6.723 | ||
Call Number | c:irua:126059 | Serial | 3836 | ||
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Author | Schrittwieser, S.; Pelaz, B.; Parak, W.J.; Lentijo-Mozo, S.; Soulantica, K.; Dieckhoff, J.; Ludwig, F.; Altantzis, T.; Bals, S.; Schotter, J. | ||||
Title | Homogeneous Protein Analysis by Magnetic Core-Shell Nanorod Probes | Type | A1 Journal article | ||
Year | 2016 | Publication | ACS applied materials and interfaces | Abbreviated Journal | Acs Appl Mater Inter |
Volume | 8 | Issue | 8 | Pages | 8893-8899 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Studying protein interactions is of vital importance both to fundamental biology research and to medical applications. Here, we report on the experimental proof of a universally applicable label-free homogeneous platform for rapid protein analysis. It is based on optically detecting changes in the rotational dynamics of magnetically agitated core-shell nanorods upon their specific interaction with proteins. By adjusting the excitation frequency, we are able to optimize the measurement signal for each analyte protein size. In addition, due to the locking of the optical signal to the magnetic excitation frequency, background signals are suppressed, thus allowing exclusive studies of processes at the nanoprobe surface only. We study target proteins (soluble domain of the human epidermal growth factor receptor 2 – sHER2) specifically binding to antibodies (trastuzumab) immobilized on the surface of our nanoprobes and demonstrate direct deduction of their respective sizes. Additionally, we examine the dependence of our measurement signal on the concentration of the analyte protein, and deduce a minimally detectable sHER2 concentration of 440 pM. For our homogeneous measurement platform, good dispersion stability of the applied nanoprobes under physiological conditions is of vital importance. To that end, we support our measurement data by theoretical modeling of the total particle-particle interaction energies. The successful implementation of our platform offers scope for applications in biomarker-based diagnostics as well as for answering basic biology questions. | ||||
Address | Molecular Diagnostics, AIT Austrian Institute of Technology , Vienna, Austria | ||||
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Language | English | Wos | 000374274900007 | Publication Date | 2016-03-29 |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1944-8244 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 7.504 | Times cited | 16 | Open Access | OpenAccess |
Notes | The authors thank Frauke Alves, Julia Bode and Fernanda Ramos Gomes from the Max-Planck-Institute of Experimental Medicine in Göttingen for providing the trastuzumab antibody in form of the Herceptin therapeutic drug. The figure showing the measurement principle has been created by Darragh Crotty (www.darraghcrotty.com). Parts of this research were supported by the European Commission FP7 NAMDIATREAM project (EU NMP4-LA-2010−246479), by the German research foundation (DFG grant GRK 1782 to W.J.P.), and by the European Research Council (ERC Starting Grant #335078 Colouratom). B.P. acknowledges a PostDoctoral fellowship from the Alexander von Humboldt foundation. (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); ; ECAS_Sara; | Approved | Most recent IF: 7.504 | ||
Call Number | c:irua:132889 | Serial | 4059 | ||
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Author | Ao, Z.; Jiang, Q.; Li, S.; Liu, H.; Peeters, F.M.; Li, S.; Wang, G. | ||||
Title | Enhancement of the stability of fluorine atoms on defective graphene and at graphene/fluorographene interface | Type | A1 Journal article | ||
Year | 2015 | Publication | ACS applied materials and interfaces | Abbreviated Journal | Acs Appl Mater Inter |
Volume | 7 | Issue | 7 | Pages | 19659-19665 |
Keywords | A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) | ||||
Abstract | Fluorinated graphene is one of the most important derivatives of graphene and has been found to have great potential in optoelectronic and photonic nanodevices. However, the stability of F atoms on fluorinated graphene under different conditions, which is essential to maintain the desired properties of fluorinated graphene, is still unclear. In this work, we investigate the diffusion of F atoms on pristine graphene, graphene with defects, and at graphene/fluorographene interfaces by using density functional theory calculations. We find that an isolated F atom diffuses easily on graphene, but those F atoms can be localized by inducing vacancies or absorbates in graphene and by creating graphene/fluorographene interfaces, which would strengthen the binding energy of F atoms on graphene and increase the diffusion energy barrier of F atoms remarkably. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000361252400018 | Publication Date | 2015-08-24 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1944-8244 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 7.504 | Times cited | 35 | Open Access | |
Notes | ; We acknowledge the financial supports from the Chancellor's Research Fellowship Program of the University of Technology Sydney, the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish Government. This research was also supported by the National Computational Infrastructure (NCI) through the merit allocation scheme and used the NCI resources and facilities in Canberra, Australia. ; | Approved | Most recent IF: 7.504; 2015 IF: 6.723 | ||
Call Number | UA @ lucian @ c:irua:128703 | Serial | 4177 | ||
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Author | Conings, B.; Bretschneider, S.A.; Babayigit, A.; Gauquelin, N.; Cardinaletti, I.; Manca, J.V.; Verbeeck, J.; Snaith, H.J.; Boyen, H.-G. | ||||
Title | Structure-property relations of methylamine vapor treated hybrid perovskite CH3NH3PbI3 films and solar cells | Type | A1 Journal article | ||
Year | 2017 | Publication | ACS applied materials and interfaces | Abbreviated Journal | Acs Appl Mater Inter |
Volume | 9 | Issue | 9 | Pages | 8092-8099 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | The power conversion efficiency of halide perovskite solar cells is heavily dependent on the perovskite layer being sufficiently smooth and pinhole-free. It has been shown that these features can be obtained even when starting out from rough and discontinuous perovskite film, by briefly exposing it to methylamine (MA) vapor. The exact underlying physical mechanisms of this phenomenon are, however, still unclear. By investigating smooth, MA treated films, based on very rough and discontinuous reference films of methylammonium triiode (MAPbI3), considering their morphology, crystalline features, local conductive properties, and charge carrier lifetime, we unravel the relation between their characteristic physical qualities and their performance in corresponding solar cells. We discover that the extensive improvement in photovoltaic performance upon MA treatment is a consequence of the induced morphological enhancement of the perovskite layer, together with improved electron injection into TiO2, which in fact compensates for an otherwise compromised bulk electronic quality, simultaneously caused by the MA treatment. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000396186000025 | Publication Date | 2017-02-10 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1944-8244 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 7.504 | Times cited | 43 | Open Access | OpenAccess |
Notes | This work was financially supported by BOF (Hasselt University) and the Research Fund Flanders (FWO). B.C. is a postdoctoral research fellow of the FWO. A.B. is financially supported by FWO and Imec. J.V. and N.G. acknowledge funding from GOA project “Solarpaint” of the University of Antwerp and FWO project G.0044.13N “Charge ordering”. The Qu-Ant-EM microscope used for this study was partly funded by the Hercules fund from the Flemish Government. The authors thank Tim Vangerven for Urbach energy determination, and Johnny Baccus and Jan Mertens for technical support. | Approved | Most recent IF: 7.504 | ||
Call Number | EMAT @ emat @ c:irua:140849 | Serial | 4422 | ||
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Author | Ustarroz, J.; Geboes, B.; Vanrompay, H.; Sentosun, K.; Bals, S.; Breugelmans, T.; Hubin, A. | ||||
Title | Electrodeposition of Highly Porous Pt Nanoparticles Studied by Quantitative 3D Electron Tomography: Influence of Growth Mechanisms and Potential Cycling on the Active Surface Area | Type | A1 Journal article | ||
Year | 2017 | Publication | ACS applied materials and interfaces | Abbreviated Journal | Acs Appl Mater Inter |
Volume | 9 | Issue | 9 | Pages | 16168-16177 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT) | ||||
Abstract | Nanoporous Pt nanoparticles (NPs) are promising fuel cell catalysts due to their large surface area and increased electrocatalytic activity towards the oxygen reduction reaction (ORR). Herein, we report on the infuence of the growth mechanisms on the surface properties of electrodeposited Pt dendritic NPs with large surface areas. The electrochemically active surface was studied by hydrogen underpotential deposition (HUPD) and compared for the rst time to high angle annular dark eld scanning transmission electron microscopy (HAADF-STEM) quantitative 3D electron tomography of individual nanoparticles. Large nucleation overpotential leads to a large surface coverage of Pt roughened spheroids, which provide large roughness factor (Rf ) but low mass-specic electrochemically active surface area (EASA). Lowering the nucleation overpotential leads to highly porous Pt NPs with pores protruding to the center of the structure. At the expense of smaller Rf , the obtained EASA values of these structures are in the range of these of large surface area supported fuel cell catalysts. The active surface area of the Pt dendritic NPs was measured by electron tomography and it was found that the potential cycling in the H adsorption/desorption and Pt oxidation/reduction region, which is generally performed to determine the EASA, leads to a signicant reduction of that surface area due to a partial collapse of their dendritic and porous morphology. Interestingly, the extrapolation of the microscopic tomography results to macroscopic electrochemical parameters indicated that the surface properties measured by H UPD are comparable to the values measured on individual NPs by electron tomography after the degradation caused by the H UPD measurement. These results highlight that the combination of electrochemical and quantitative 3D surface analysis techniques is essential to provide insights into the surface properties, the electrochemical stability and, hence, the applicability of these materials. Moreover, it indicates that care must be taken with widely used electrochemical methods of surface area determination, especially in the case of large surface area and possibly unstable nanostructures, since the measured surface can be strongly aected by the measurement itself. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000401782500028 | Publication Date | 2017-04-18 | |
Series Editor | Series Title | Abbreviated Series Title | |||
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ISSN | 1944-8244 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 7.504 | Times cited | 24 | Open Access | OpenAccess |
Notes | Jon Ustarroz acknowledges funding from the Fonds Wetenschappelijk Onderzoek in Flanders (FWO, postdoctoral grant 12I7816N). S. Bals acknowledges funding from the European Research Council (Starting Grant No. COLOURATOMS 335078). S.B. and T.B. acknowledge the University of Antwerp for nancial support in the frame of a GOA project. H.V. gratefully acknowledges nancial support by the Flemish Fund for Scientic Research (FWO Vlaanderen). All the authors acknowledge Laurens Stevaert for his contribution to the work presented in this manuscript. (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); ECAS_Sara | Approved | Most recent IF: 7.504 | ||
Call Number | EMAT @ emat @ c:irua:142345UA @ admin @ c:irua:142345 | Serial | 4552 | ||
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