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| Author | Ramachandran, R.K.; Filez, M.; Solano, E.; Poelman, H.; Minjauw, M.M.; Van Daele, M.; Feng, J.-Y.; La Porta, A.; Altantzis, T.; Fonda, E.; Coati, A.; Garreau, Y.; Bals, S.; Marin, G.B.; Detavernier, C.; Dendooven, J. | ||||
| Title | Chemical and Structural Configuration of Pt Doped Metal Oxide Thin Films Prepared by Atomic Layer Deposition | Type | A1 Journal article | ||
| Year | 2019 | Publication | Chemistry of materials | Abbreviated Journal | Chem Mater |
| Volume | 31 | Issue | 31 | Pages | 9673-9683 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT) | ||||
| Abstract | Pt doped semiconducting metal oxides and Pt metal clusters embedded in an oxide matrix are of interest for applications such as catalysis and gas sensing, energy storage and memory devices. Accurate tuning of the dopant level is crucial for adjusting the properties of these materials. Here, a novel atomic layer deposition (ALD) based method for doping Pt into In2O3 in specific, and metals in metal oxides in general, is demonstrated. This approach combines alternating exposures of Pt and In2O3 ALD processes in a single ‘supercycle’, followed by supercycle repetition leading to multilayered nanocomposites. The atomic level control of ALD and its conformal nature make the method suitable for accurate dopant control even on high surface area supports. Oxidation state, local structural environment and crystalline phase of the embedded Pt dopants were obtained by means of X-ray characterization methods and high angle annular dark-field scanning transmission electron microscopy (HAADF-STEM). In addition, this approach allows characterization of the nucleation stages of metal ALD processes, by stacking those states multiple times in an oxide matrix. Regardless of experimental conditions, a few Pt ALD cycles leads to the formation of oxidized Pt species due to their highly dispersed nature, as proven by X-ray absorption spectroscopy (XAS). Grazing-incidence small-angle X-ray scattering (GISAXS) and highresolution scanning transmission electron microscopy, combined with energy dispersive X-ray spectroscopy (HR-STEM/EDXS) show that Pt is evenly distributed in the In2O3 metal oxide matrix without the formation of clusters. For a larger number of Pt ALD cycles, typ. > 10, the oxidation state gradually evolves towards fully metallic, and metallic Pt clusters are obtained within the In2O3 metal oxide matrix. This work reveals how tuning of the ALD supercycle approach for Pt doping allows controlled engineering of the Pt compositional and structural configuration within a metal oxide matrix. |
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| Language | Wos | 000502418000010 | Publication Date | 2019-11-11 | |
| 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 | 6 | Open Access | OpenAccess |
| Notes | This research was supported by the Flemish Research Foundation (FWO-Vlaanderen), the Flemish Government (Long term structural funding – Methusalem funding and Medium scale research infrastructure funding-Hercules funding), the Special Research Fund BOF of Ghent University (GOA 01G01513) and the CALIPSO Trans National Access Program funded by the European Commission in supplying financing of travel costs. We are grateful to the SIXS and SAMBA-SOLEIL staff for smoothly running the beamline facilities. J.D. and R.K.R. are postdoctoral fellows of the FWO. | Approved | Most recent IF: 9.466 | ||
| Call Number | EMAT @ emat @c:irua:164056 | Serial | 5380 | ||
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| Author | Peeters, H.; Keulemans, M.; Nuyts, G.; Vanmeert, F.; Li, C.; Minjauw, M.; Detavernier, C.; Bals, S.; Lenaerts, S.; Verbruggen, S.W. | ||||
| Title | Plasmonic gold-embedded TiO2 thin films as photocatalytic self-cleaning coatings | Type | A1 Journal article | ||
| Year | 2020 | Publication | Applied Catalysis B-Environmental | Abbreviated Journal | Appl Catal B-Environ |
| Volume | 267 | Issue | 267 | Pages | 118654 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Sustainable Energy, Air and Water Technology (DuEL) | ||||
| Abstract | Transparent photocatalytic TiO2 thin films hold great potential in the development of self-cleaning glass sur- faces, but suffer from a poor visible light response that hinders the application under actual sunlight. To alleviate this problem, the photocatalytic film can be modified with plasmonic nanoparticles that interact very effectively with visible light. Since the plasmonic effect is strongly concentrated in the near surroundings of the nano- particle surface, an approach is presented to embed the plasmonic nanostructures in the TiO2 matrix itself, rather than deposit them loosely on the surface. This way the interaction interface is maximised and the plasmonic effect can be fully exploited. In this study, pre-fabricated gold nanoparticles are made compatible with the organic medium of a TiO2 sol-gel coating suspension, resulting in a one-pot coating suspension. After spin coating, homogeneous, smooth, highly transparent and photoactive gold-embedded anatase thin films are ob- tained. |
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| Language | Wos | 000518865300002 | Publication Date | 2020-01-18 | |
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| ISSN | 0926-3373 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 22.1 | Times cited | 57 | Open Access | OpenAccess |
| Notes | H.P. is grateful to the Research Foundation Flanders (FWO) for an aspirant PhD scholarship. | Approved | Most recent IF: 22.1; 2020 IF: 9.446 | ||
| Call Number | EMAT @ emat @c:irua:165616 | Serial | 5446 | ||
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| Author | Comrie, C.M.; Ahmed, A.; Smeets, D.; Demeulemeester, J.; Turner, S.; Van Tendeloo, G.; Detavernier, C.; Vantomme, A. | ||||
| Title | Effect of high temperature deposition on CoSi2 phase formation | Type | A1 Journal article | ||
| Year | 2013 | Publication | Journal of applied physics | Abbreviated Journal | J Appl Phys |
| Volume | 113 | Issue | 23 | Pages | 234902-234908 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | This paper discusses the nucleation behaviour of the CoSi to CoSi2 transformation from cobalt silicide thin films grown by deposition at elevated substrate temperatures ranging from 375 °C to 600 °C. A combination of channelling, real-time Rutherford backscattering spectrometry, real-time x-ray diffraction, and transmission electron microscopy was used to investigate the effect of the deposition temperature on the subsequent formation temperature of CoSi2, its growth behaviour, and the epitaxial quality of the CoSi2 thus formed. The temperature at which deposition took place was observed to exert a significant and systematic influence on both the formation temperature of CoSi2 and its growth mechanism. CoSi films grown at the lowest temperatures were found to increase the CoSi2 nucleation temperature above that of CoSi2 grown by conventional solid phase reaction, whereas the higher deposition temperatures reduced the nucleation temperature significantly. In addition, a systematic change in growth mechanism of the subsequent CoSi2 growth occurs as a function of deposition temperature. First, the CoSi2 growth rate from films grown at the lower reactive deposition temperatures is substantially lower than that grown at higher reactive deposition temperatures, even though the onset of growth occurs at a higher temperature, Second, for deposition temperatures below 450 °C, the growth appears columnar, indicating nucleation controlled growth. Elevated deposition temperatures, on the other hand, render the CoSi2 formation process layer-by-layer which indicates enhanced nucleation of the CoSi2 and diffusion controlled growth. Our results further indicate that this observed trend is most likely related to stress and changes in microstructure introduced during reactive deposition of the CoSi film. The deposition temperature therefore provides a handle to tune the CoSi2 growth mechanism. | ||||
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American Institute of Physics | Place of Publication | New York, N.Y. | Editor | |
| Language | Wos | 000321011700077 | Publication Date | 2013-06-17 | |
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0021-8979; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.068 | Times cited | 2 | Open Access | |
| Notes | Fwo; Countatoms | Approved | Most recent IF: 2.068; 2013 IF: 2.185 | ||
| Call Number | UA @ lucian @ c:irua:109266 | Serial | 815 | ||
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| Author | Geenen, F.A.; van Stiphout, K.; Nanakoudis, A.; Bals, S.; Vantomme, A.; Jordan-Sweet, J.; Lavoie, C.; Detavernier, C. | ||||
| Title | Controlling the formation and stability of ultra-thin nickel silicides : an alloying strategy for preventing agglomeration | Type | A1 Journal article | ||
| Year | 2018 | Publication | Journal of applied physics | Abbreviated Journal | J Appl Phys |
| Volume | 123 | Issue | 123 | Pages | 075303 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | The electrical contact of the source and drain regions in state-of-the-art CMOS transistors is nowadays facilitated through NiSi, which is often alloyed with Pt in order to avoid morphological agglomeration of the silicide film. However, the solid-state reaction between as-deposited Ni and the Si substrate exhibits a peculiar change for as-deposited Ni films thinner than a critical thickness of t(c) = 5 nm. Whereas thicker films form polycrystalline NiSi upon annealing above 450 degrees C, thinner films form epitaxial NiSi2 films that exhibit a high resistance toward agglomeration. For industrial applications, it is therefore of utmost importance to assess the critical thickness with high certainty and find novel methodologies to either increase or decrease its value, depending on the aimed silicide formation. This paper investigates Ni films between 0 and 15 nm initial thickness by use of “thickness gradients,” which provide semi-continuous information on silicide formation and stability as a function of as-deposited layer thickness. The alloying of these Ni layers with 10% Al, Co, Ge, Pd, or Pt renders a significant change in the phase sequence as a function of thickness and dependent on the alloying element. The addition of these ternary impurities therefore changes the critical thickness t(c). The results are discussed in the framework of classical nucleation theory. Published by AIP Publishing. | ||||
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American Institute of Physics | Place of Publication | New York, N.Y. | Editor | |
| Language | Wos | 000425807400018 | Publication Date | 2018-02-21 | |
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0021-8979; 1089-7550 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.068 | Times cited | 23 | Open Access | OpenAccess |
| Notes | ; The authors acknowledge the FWO Vlaanderen, the Hercules Foundation, and BOF-UGent (GOA 01G01513) for providing financial support for this work. This research used resources of the National Synchrotron Light Source, a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Brookhaven National Laboratory under Contract No. DE-AC02-98CH10886. ; | Approved | Most recent IF: 2.068 | ||
| Call Number | UA @ lucian @ c:irua:149912UA @ admin @ c:irua:149912 | Serial | 4929 | ||
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