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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.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000518865300002 Publication Date 2020-01-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
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 (up) 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 Claes, N.; Asapu, R.; Blommaerts, N.; Verbruggen, S.W.; Lenaerts, S.; Bals, S.
Title Characterization of silver-polymer core–shell nanoparticles using electron microscopy Type A1 Journal article
Year 2018 Publication Nanoscale Abbreviated Journal Nanoscale
Volume 10 Issue 10 Pages 9186-9191
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Sustainable Energy, Air and Water Technology (DuEL)
Abstract Silver-polymer core–shell nanoparticles show interesting optical properties, making them widely applicable in the field of plasmonics. The uniformity, thickness and homogeneity of the polymer shell will affect the properties of the system which makes a thorough structural characterization of these core–shell silver-polymer nanoparticles of great importance. However, visualizing the shell and the particle simultaneously is far from straightforward due to the sensitivity of the polymer shell towards the electron beam. In this study, we use different 2D and 3D electron microscopy techniques to investigate different structural aspects of the polymer coating.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000437007700028 Publication Date 2018-04-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2040-3364 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 7.367 Times cited 11 Open Access OpenAccess
Notes (up) N. C. and S. B. acknowledge financial support from European Research Council (ERC Starting Grant #335078-COLOURATOMS) and from the FWO through project funding (G038116N). R. A. and S. L. acknowledge the Research Foundation Flanders (FWO) for financial support. (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); ECAS_Sara Approved Most recent IF: 7.367
Call Number EMAT @ emat @c:irua:151290UA @ admin @ c:irua:151290 Serial 4959
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Author Blommaerts, N.; Asapu, R.; Claes, N.; Bals, S.; Lenaerts, S.; Verbruggen, S.W.
Title Gas phase photocatalytic spiral reactor for fast and efficient pollutant degradation Type A1 Journal article
Year 2017 Publication Chemical engineering journal Abbreviated Journal Chem Eng J
Volume 316 Issue 316 Pages 850-856
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Sustainable Energy, Air and Water Technology (DuEL)
Abstract Photocatalytic reactors for the degradation of gaseous organic pollutants often suffer from major limitations such as small reaction area, sub-optimal irradiation conditions and thus limited reaction rate. In this work, an alternative solution is presented that involves a glass tube coated on the inside with (silvermodified) TiO2 and spiraled around a UVA lamp. First, the spiral reactor is coated from the inside with TiO2 using an experimentally verified procedure that is optimized toward UV light transmission. This procedure is kept as simple as possible and involves a single casting step of a 1 wt% suspension of TiO2 in ethanol through the spiral. This results in a coated tube that absorbs nearly all incident UV light under the experimental conditions used. The optimized coated spiral reactor is then benchmarked to a conventional annular photoreactor of the same outer dimensions and total catalyst loading over a broad range of experimental conditions. Although residence time distribution experiments indicate slightly longer dwelling of molecules in the spiral reactor, no significant difference in by-passing of gas between the spiral reactor and the annular reactor can be claimed. Acetaldehyde degradation efficiency of 100% is obtained with the spiral reactor for a residence time as low as 60 s, whereas the annular reactor could not achieve full degradation even at 1000 s residence time. In a final case study, addition of long-term stable silver nanoparticles, protected by an ultra-thin polymer shell applied via the layer-by-layer (LbL) method, to the spiral reactor coating is shown to double the degradation efficiency and provides an interesting strategy to cope with higher pollutant concentrations without changing the overall dimensions.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000398985200089 Publication Date 2017-02-08
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1385-8947 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.216 Times cited 30 Open Access OpenAccess
Notes (up) N.B. wishes to thank the University of Antwerp – Belgium for financial support. N.C. and S.B. acknowledge financial support from European Research Council (ERC Starting Grant #335078- COLOURATOM). S.W.V. acknowledges the Research Foundation – Flanders (FWO) for a postdoctoral fellowship. (ROMEO:green; preprint:; postprint:can ; pdfversion:cannot); ecas_sara Approved Most recent IF: 6.216
Call Number EMAT @ emat @ c:irua:140925UA @ admin @ c:irua:140925 Serial 4481
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Author Blommaerts, N.; Hoeven, N.; Arenas Esteban, D.; Campos, R.; Mertens, M.; Borah, R.; Glisenti, A.; De Wael, K.; Bals, S.; Lenaerts, S.; Verbruggen, S.W.; Cool, P.
Title Tuning the turnover frequency and selectivity of photocatalytic CO2 reduction to CO and methane using platinum and palladium nanoparticles on Ti-Beta zeolites Type A1 Journal article
Year 2021 Publication Chemical Engineering Journal Abbreviated Journal Chem Eng J
Volume 410 Issue Pages 128234
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL); Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract A Ti-Beta zeolite was used in gas phase photocatalytic CO2 reduction to reduce the charge recombination rate and increase the surface area compared to P25 as commercial benchmark, reaching 607 m2 g-1. By adding Pt nanoparticles, the selectivity can be tuned toward CO, reaching a value of 92% and a turnover frequency (TOF) of 96 µmol.gcat-1.h-1, nearly an order of magnitude higher in comparison with P25. By adding Pd nanoparticles the selectivity can be shifted from CO (70% for a bare Ti-Beta zeolite), toward CH4 as the prevalent species (60%). In this way, the selectivity toward CO or CH4 can be tuned by either using Pt or Pd. The TOF values obtained in this work outperform reported state-of-the-art values in similar research. The improved activity by adding the nanoparticles was attributed to an improved charge separation efficiency, together with a plasmonic contribution of the metal nanoparticles under the applied experimental conditions.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000623394200004 Publication Date 2021-01-09
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1385-8947 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.216 Times cited 15 Open Access OpenAccess
Notes (up) N.B., S.L., S.W.V. and P.C. wish to thank the Flemish government and Catalisti for financial support and coordination in terms of a sprint SBO in the context of the moonshot project D2M. N.H. thanks the Flanders Innovation and Entrepreneurship (VLAIO) for the financial support. The Systemic Physiological and Ecotoxicological Research (SPHERE) group, R. Blust, University of Antwerp is acknowledged for the ICP-MS measurements. Approved Most recent IF: 6.216
Call Number EMAT @ emat @c:irua:174591 Serial 6662
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Author Borah, R.; Ninakanti, R.; Bals, S.; Verbruggen, S.W.
Title Plasmon resonance of gold and silver nanoparticle arrays in the Kretschmann (attenuated total reflectance) vs. direct incidence configuration Type A1 Journal article
Year 2022 Publication Scientific reports Abbreviated Journal Sci Rep-Uk
Volume 12 Issue 1 Pages 15738-19
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Sustainable Energy, Air and Water Technology (DuEL)
Abstract While the behaviour of plasmonic solid thin films in the Kretschmann (also known as Attenuated Total Reflection, ATR) configuration is well-understood, the use of discrete nanoparticle arrays in this optical configuration is not thoroughly explored. It is important to do so, since close packed plasmonic nanoparticle arrays exhibit exceptionally strong light-matter interactions by plasmonic coupling. The present work elucidates the optical properties of plasmonic Au and Ag nanoparticle arrays in both the direct normal incidence and Kretschmann configuration by numerical models, that are validated experimentally. First, hexagonal close packed Au and Ag nanoparticle films/arrays are obtained by air–liquid interfacial assembly. The numerical models for the rigorous solution of the Maxwell’s equations are validated using experimental optical spectra of these films before systematically investigating various parameters. The individual far-field/near-field optical properties, as well as the plasmon relaxation mechanism of the nanoparticles, vary strongly as the packing density of the array increases. In the Kretschmann configuration, the evanescent fields arising from p – and s -polarized (or TM and TE polarized) incidence have different directional components. The local evanescent field intensity and direction depends on the polarization, angle of incidence and the wavelength of incidence. These factors in the Kretschmann configuration give rise to interesting far-field as well as near-field optical properties. Overall, it is shown that plasmonic nanoparticle arrays in the Kretschmann configuration facilitate strong broadband absorptance without transmission losses, and strong near-field enhancement. The results reported herein elucidate the optical properties of self-assembled nanoparticle films, pinpointing the ideal conditions under which the normal and the Kretschmann configuration can be exploited in multiple light-driven applications.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000858344700048 Publication Date 2022-09-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2045-2322 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.6 Times cited 11 Open Access OpenAccess
Notes (up) R.B. acknowledges financial support from the University of Antwerp Special Research Fund (BOF) for a DOCPRO4 doctoral scholarship (Grant FN541100001). Approved Most recent IF: 4.6
Call Number UA @ admin @ c:irua:190864 Serial 7194
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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.
Address
Corporate Author Thesis
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 (up) 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
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Author Dingenen, F.; Blommaerts, N.; Van Hal, M.; Borah, R.; Arenas-Esteban, D.; Lenaerts, S.; Bals, S.; Verbruggen, S.W.
Title Layer-by-Layer-Stabilized Plasmonic Gold-Silver Nanoparticles on TiO2: Towards Stable Solar Active Photocatalysts Type A1 Journal article
Year 2021 Publication Nanomaterials Abbreviated Journal Nanomaterials-Basel
Volume 11 Issue 10 Pages 2624
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract To broaden the activity window of TiO2, a broadband plasmonic photocatalyst has been designed and optimized. This plasmonic ‘rainbow’ photocatalyst consists of TiO2 modified with gold–silver composite nanoparticles of various sizes and compositions, thus inducing a broadband interaction with polychromatic solar light. However, these nanoparticles are inherently unstable, especially due to the use of silver. Hence, in this study the application of the layer-by-layer technique is introduced to create a protective polymer shell around the metal cores with a very high degree of control. Various TiO2 species (pure anatase, PC500, and P25) were loaded with different plasmonic metal loadings (0–2 wt %) in order to identify the most solar active composite materials. The prepared plasmonic photocatalysts were tested towards stearic acid degradation under simulated sunlight. From all materials tested, P25 + 2 wt % of plasmonic ‘rainbow’ nanoparticles proved to be the most promising (56% more efficient compared to pristine P25) and was also identified as the most cost-effective. Further, 2 wt % of layer-by-layer-stabilized ‘rainbow’ nanoparticles were loaded on P25. These layer-by-layer-stabilized metals showed superior stability under a heated oxidative atmosphere, as well as in a salt solution. Finally, the activity of the composite was almost completely retained after 1 month of aging, while the nonstabilized equivalent lost 34% of its initial activity. This work shows for the first time the synergetic application of a plasmonic ‘rainbow’ concept and the layer-by-layer stabilization technique, resulting in a promising solar active, and long-term stable photocatalyst.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000712759800001 Publication Date 2021-10-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2079-4991 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.553 Times cited 7 Open Access OpenAccess
Notes (up) Research was funded by Research Foundation—Flanders (FWO), FN 700300001— Aspirant F. Dingenen. Approved Most recent IF: 3.553
Call Number EMAT @ emat @c:irua:183281 Serial 6812
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Author Verbruggen, S.W.; Keulemans, M.; Goris, B.; Blommaerts, N.; Bals, S.; Martens, J.A.; Lenaerts, S.
Title Plasmonic ‘rainbow’ photocatalyst with broadband solar light response for environmental applications Type A1 Journal article
Year 2016 Publication Applied catalysis : B : environmental Abbreviated Journal Appl Catal B-Environ
Volume 188 Issue 188 Pages 147-153
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Sustainable Energy, Air and Water Technology (DuEL)
Abstract We propose the concept of a ‘rainbow’ photocatalyst that consists of TiO2 modified with gold-silver alloy nanoparticles of various sizes and compositions, resulting in a broad plasmon absorption band that covers the entire UV–vis range of the solar spectrum. It is demonstrated that this plasmonic ‘rainbow’ photocatalyst is 16% more effective than TiO2 P25 under both simulated and real solar light for pollutant degradation at the solid-gas interface. With this we provide a promising strategy to maximize the spectral response for solar to chemical energy conversion.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000372677500016 Publication Date 2016-02-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0926-3373 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 9.446 Times cited 47 Open Access OpenAccess
Notes (up) S.W.V. and B.G. acknowledge the Research Foundation—Flanders (FWO) for a postdoctoral fellowship. M.K. acknowledges IWT for the doctoral scholarship. S.B. acknowledges the European Research Council (ERC) for financial support through the ERC grant agreement no. 335078-COLOURATOM. J.A.M. acknowledges the Flemish government for long-term structural funding (Methusalem).; ECAS_Sara; (ROMEO:green; preprint:; postprint:can ; pdfversion:cannot); Approved Most recent IF: 9.446
Call Number c:irua:130995 Serial 4061
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Author Kurttepeli, M.; Deng, S.; Verbruggen, S.W.; Guzzinati, G.; Cott, D.J.; Lenaerts, S.; Verbeeck, J.; Van Tendeloo, G.; Detavernier, C.; Bals, S.
Title Synthesis and characterization of photoreactive TiO2carbon nanosheet composites Type A1 Journal article
Year 2014 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C
Volume 118 Issue 36 Pages 21031-21037
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Sustainable Energy, Air and Water Technology (DuEL)
Abstract We report the atomic layer deposition of titanium dioxide on carbon nanosheet templates and investigate the effects of postdeposition annealing in a helium environment using different characterization techniques. The crystallization of the titanium dioxide coating upon annealing is observed using in situ X-ray diffraction. The (micro)structural characterization of the films is carried out by scanning electron microscopy and advanced transmission electron microscopy techniques. Our study shows that the annealing of the atomic layer deposition processed and carbon nanosheets templated titanium dioxide layers in helium environment resulting in the formation of a porous, nanocrystalline and photocatalytically active titanium dioxide-carbon nanosheet composite film. Such composites are suitable for photocatalysis and dye-sensitized solar cells applications.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000341619500034 Publication Date 2014-08-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-7447;1932-7455; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.536 Times cited 9 Open Access OpenAccess
Notes (up) This research was funded by the Flemish research foundation FWO-Vlaanderen, by the European Research Council (Starting Grant No. 239865) and by the Special Research Fund BOF of Ghent University (GOA-01G01513). G.G, M.K., J.V., S.B., and G.V.T. acknowledge funding from the European Research Council under the seventh Framework Program (FP7), ERC Starting Grant No. 278510 VORTEX and No. 335078 COLOURATOMS. ECASJO;; ECASSara; (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); Approved Most recent IF: 4.536; 2014 IF: 4.772
Call Number UA @ lucian @ c:irua:119085 Serial 3416
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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.
Address
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 (up) 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
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Author Borah, R.; Verbruggen, S.W.
Title Silver–Gold Bimetallic Alloy versus Core–Shell Nanoparticles: Implications for Plasmonic Enhancement and Photothermal Applications Type A1 Journal article
Year 2020 Publication Journal Of Physical Chemistry C Abbreviated Journal J Phys Chem C
Volume Issue Pages acs.jpcc.0c02630
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Bimetallic plasmonic nanoparticles enable tuning of the optical response and chemical stability by variation of the composition. The present numerical simulation study compares Ag–Au alloy, Ag@Au core–shell, and Au@Ag core–shell bimetallic plasmonic nanoparticles of both spherical and anisotropic (nanotriangle and nanorods) shapes. By studying both spherical and anisotropic (with LSPR in the near-infrared region) shapes, cases with and without interband transitions of Au can be decoupled. Explicit comparisons are facilitated by numerical models supported by careful validation and examination of optical constants of Au–Ag alloys reported in the literature. Although both Au–Ag core–shell and alloy nanoparticles exhibit an intermediary optical response between that of pure Ag and Au nanoparticles, there are noticeable differences in the spectral characteristics. Also, the effect of the bimetallic constitution in anisotropic nanoparticles is starkly different from that in spherical nanoparticles due to the absence of Au interband transitions in the former case. In general, the improved chemical stability of Ag nanoparticles by incorporation of Au comes with a cost of reduction in plasmonic enhancement, also applicable to anisotropic nanoparticles with a weaker effect. A photothermal heat transfer study confirms that increased absorption by the incorporation of Au in spherical Ag nanoparticles also results in an increased steady-state temperature. On the other hand, anisotropic nanoparticles are inherently better absorbers and hence better photothermal sources, and their photothermal properties are apparently not strongly affected by the incorporation of one metal in the other. This study of the optical/spectral and photothermal characteristics of bimetallic Au–Ag alloy versus core–shell nanoparticles provides detailed physical insight for development of new taylor-made plasmonic nanostructures.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000538758700039 Publication Date 2020-05-19
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-7447 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.7 Times cited Open Access
Notes (up) Universiteit Antwerpen, DOCPRO4 Rituraj Borah ; Approved Most recent IF: 3.7; 2020 IF: 4.536
Call Number DuEL @ duel @c:irua:169223 Serial 6367
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Author Borah, R.; Verbruggen, S.W.
Title Silver–Gold Bimetallic Alloy versus Core–Shell Nanoparticles: Implications for Plasmonic Enhancement and Photothermal Applications Type A1 Journal article
Year 2020 Publication Journal Of Physical Chemistry C Abbreviated Journal J Phys Chem C
Volume Issue Pages acs.jpcc.0c02630
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Bimetallic plasmonic nanoparticles enable tuning of the optical response and chemical stability by variation of the composition. The present numerical simulation study compares Ag–Au alloy, Ag@Au core–shell, and Au@Ag core–shell bimetallic plasmonic nanoparticles of both spherical and anisotropic (nanotriangle and nanorods) shapes. By studying both spherical and anisotropic (with LSPR in the near-infrared region) shapes, cases with and without interband transitions of Au can be decoupled. Explicit comparisons are facilitated by numerical models supported by careful validation and examination of optical constants of Au–Ag alloys reported in the literature. Although both Au–Ag core–shell and alloy nanoparticles exhibit an intermediary optical response between that of pure Ag and Au nanoparticles, there are noticeable differences in the spectral characteristics. Also, the effect of the bimetallic constitution in anisotropic nanoparticles is starkly different from that in spherical nanoparticles due to the absence of Au interband transitions in the former case. In general, the improved chemical stability of Ag nanoparticles by incorporation of Au comes with a cost of reduction in plasmonic enhancement, also applicable to anisotropic nanoparticles with a weaker effect. A photothermal heat transfer study confirms that increased absorption by the incorporation of Au in spherical Ag nanoparticles also results in an increased steady-state temperature. On the other hand, anisotropic nanoparticles are inherently better absorbers and hence better photothermal sources, and their photothermal properties are apparently not strongly affected by the incorporation of one metal in the other. This study of the optical/spectral and photothermal characteristics of bimetallic Au–Ag alloy versus core–shell nanoparticles provides detailed physical insight for development of new taylor-made plasmonic nanostructures.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000538758700039 Publication Date 2020-05-19
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-7447 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.7 Times cited Open Access
Notes (up) Universiteit Antwerpen, DOCPRO4 Rituraj Borah ; Approved Most recent IF: 3.7; 2020 IF: 4.536
Call Number DuEL @ duel @c:irua:169223 Serial 6368
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Author Blommaerts, N.; Vanrompay, H.; Nuti, S.; Lenaerts, S.; Bals, S.; Verbruggen, S.W.
Title Unraveling Structural Information of Turkevich Synthesized Plasmonic Gold-Silver Bimetallic Nanoparticles Type A1 Journal article
Year 2019 Publication Small Abbreviated Journal Small
Volume 15 Issue 15 Pages 1902791
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Sustainable Energy, Air and Water Technology (DuEL)
Abstract For the synthesis of gold-silver bimetallic nanoparticles, the Turkevich method has been the state-of-the-art method for several decades. It has been presumed that this procedure results in a homogeneous alloy, although this has been debatable for many years. In this work, it is shown that neither a full alloy, nor a perfect core-shell particle is formed but rather a core-shell-like particle with altering metal composition along the radial direction. In-depth wet-chemical experiments are performed in combination with advanced transmission electron microscopy, including EDX tomography, and Finite Element Method modeling to support the observations. From the electron tomography results, the core-shell structure could be clearly visualized and the spatial distribution of gold and silver atoms could be quantified. Theoretical simulations are performed to demonstrate that even though UV-Vis spectra show only one plasmon band, this still originates from core-shell type structures. The simulations also indicate that the core-shell morphology does not so much affect the location of the plasmon band, but mainly results in significant band broadening. Wet-chemistry experiments provide the evidence that the synthesis pathway starts with gold enriched alloy cores, and later on in the synthesis mainly silver is incorporated to end up with a silver enriched alloy shell.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000482637100001 Publication Date 2019-08-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1613-6810 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 8.643 Times cited 26 Open Access OpenAccess
Notes (up) Universiteit Antwerpen; Fonds Wetenschappelijk Onderzoek, 1S32617N G.0369.15N G.0381.16N ; Approved Most recent IF: 8.643
Call Number EMAT @ emat @c:irua:161636 Serial 5290
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