References of "Heinrichs, Benoît"
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See detailTransitioning from conventional batch to microfluidic processes for the efficient singlet oxygen photooxygenation of methionine
Mendoza Gallego, Carlos ULiege; Emmanuel, Noémie ULiege; Pàez Martinez, Carlos ULiege et al

in Journal of Photochemistry and Photobiology A: Chemistry (2018), 356

Singlet oxygen-based photocatalytic oxygenation reactions have emerged as an efficient technology to synthesize value-added organic molecules. Among organic substrates, bio-sourced molecules such as ... [more ▼]

Singlet oxygen-based photocatalytic oxygenation reactions have emerged as an efficient technology to synthesize value-added organic molecules. Among organic substrates, bio-sourced molecules such as aminoacids or terpenes have a promising forecast as synthetic building blocks. A pseudo first-order kinetic study for the photocatalytic oxygenation of natural amino acid (L)-methionine was carried out in a macroscopic batch reactor. Various parameters were studied, including the effect of the photosensitizer (Rose Bengal, RB) concentration, the intensity of the light and the O2 flow in terms of apparent kinetic constants and space-time yields. The identification of important limiting parameters as pressure, gas flow or light efficiency during the photocatalytic oxygenation of methionine allowed its transition from macroscopic batch reactor to continuous-flow microreactor. [less ▲]

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See detailIntegrated continuous flow photoreactors: Photooxidation of (L)-methionine with singlet oxygen
Emmanuel, Noémie ULiege; Mendoza Gallego, Carlos ULiege; Winter, Marc et al

Poster (2018, February 06)

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See detailGold bipyramids/SiO2 core-shell nanoparticles for an enhanced generation of singlet oxygen - Application in photocatalytic oxygenation
Mendoza Gallego, Carlos ULiege; Chateau, D.; Desert, Anthony et al

Conference (2018)

Gold nanomaterials display interesting nanoplasmonic features with potential application in various fields depending on the size and shape of the metal nanoparticle (NP). Au bipyramids (AuBPs) exhibit ... [more ▼]

Gold nanomaterials display interesting nanoplasmonic features with potential application in various fields depending on the size and shape of the metal nanoparticle (NP). Au bipyramids (AuBPs) exhibit intense and well-defined plasmon resonance, easily tunable with the aspect ratio and synergy between Au NPs and chromophores can enhance the photophysical properties of nearby molecules. In Rose Bengal (RB)-NPs systems for the production of singlet oxygen (1O2), it is now well established that the control of the dye-to-NP distance ranging from 10 to 20 nm is crucial to achieve the proper coupling between plasmon resonance and the dye1. We have developed AuBPs@mesoporous SiO2 core-shell nanostructures to control the distance between metallic surface and photosensitizers in order to increase the production of 1O2 through metal-enhanced fluorescence (MEF). An enhancement of 1O2 generation has been shown with the obtained anisotropic AuBPs and AuBPs@mSiO2 in presence of RB using different methods of 1O2 quantification. They are of interest to the application in photooxygenation reactions e.g. α-terpinene to ascaridole, an anthelmintic drug. [less ▲]

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See detailLarge scale production of photocatalytic TiO2 coating for volatile organic compound (VOC) air remediation
Mahy, Julien ULiege; Lambert, Stéphanie ULiege; Geens, Jérémy ULiege et al

in AIMS Materials Science (2018), 5(5), 945-956

In this work, a pure TiO2 colloid was produced at pilot scale of 5 L and deposited on stainless steel with a pilot roll-to-roll line to produce photocatalytic coating for VOC degradation. The pure TiO2 ... [more ▼]

In this work, a pure TiO2 colloid was produced at pilot scale of 5 L and deposited on stainless steel with a pilot roll-to-roll line to produce photocatalytic coating for VOC degradation. The pure TiO2 colloid was synthesized with an aqueous sol–gel process, producing crystalline nanoparticles around 4–5 nm (mainly anatase phase) dispersed in water. The crystalline phases were produced at low temperature (<100 ℃) without calcination step. The crystalline coating produced with roll-to-roll process was very thin, around 50 nm. The photoactivity of this coating towards VOC destruction was evaluated on the degradation of acetaldehyde; the measured activity of the coating was 35 ± 5%. With the use of mass spectrometer, it was shown that acetaldehyde was mainly converted in CO2. The durability of the coating was assessed after 1, 2 and 3 weeks, and showed that the photoactivity stayed constant for this period. [less ▲]

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See detailAcid acting as redispersing agent to form stable colloids from photoactive crystalline aqueous sol–gel TiO2 powder
Mahy, Julien ULiege; Deschamps, Fabien ULiege; Collard, Valérie ULiege et al

in Journal of Sol-Gel Science and Technology (2018), 87

In this work, the redispersion of three nanocrystalline TiO2 colloids is studied: one pure and two Fe-doped titania. These three colloids are produced by an easy aqueous sol-gel synthesis using ... [more ▼]

In this work, the redispersion of three nanocrystalline TiO2 colloids is studied: one pure and two Fe-doped titania. These three colloids are produced by an easy aqueous sol-gel synthesis using precipitation-acidic peptization of Ti precursor. For the two Fe-doped TiO2, one is doped during synthesis (primary doping) and the other is doped after the synthesis (secondary doping). The initial colloids are composed of crystalline TiO2 particles around 7 nm with good photocatalytic properties, tested on PNP degradation under visible light (wavelength > 390 nm). The powders obtained by air drying of these three colloids are redispersed in water to produce colloids which are compared to the initial colloid produced. For each colloid, 5 cycles of drying-redispersion are achieved. The colloids are characterized by dynamic light scattering, zeta potential measurements, inductively coupled plasma–atomic emission spectroscopy, X-ray diffraction, nitrogen adsorption-desorption measurements, Mössbauer spectroscopy, diffuse reflectance spectroscopy, and photocatalytic tests. The results show that similar products are obtained between the cycles, maintaining homologous properties of colloids. This property of redispersion is mainly due to the acid (HNO3, HCl, or H2SO4) which protonates the surface of the TiO2 nanoparticle leading to high surface charges and electrostatic repulsions between aggregates. This property can be very useful for industrial applications of this synthesis, especially as it allows the volume and weight to be reduced for transportation and storage. Moreover, results show that the pure TiO2 powder can be doped during its redispersion step. The redispersion of the TiO2 developed here is possible without surface functionalization or multiple step processes, contrary to commercial Degussa P25. A two year stability study of all the produced colloids has been performed by following the evolution of the macroscopic aspect and the physico-chemical properties of these sols. This study showed high stability of the produced colloids. [less ▲]

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See detailRole of defects on the enhancement of the photocatalytic response of ZnO nanostructures
Montero-Munoz, M.; Ramos-Ibarra, J. E.; Rodríguez-Páez, Jorge E. et al

in Applied Surface Science (2018), 448

Zinc oxide (ZnO) nanostructures have been synthesized by a simple controlled precipitation method to study the effects of the type solvent – including water, acetic acid and ethylene glycol – on the ... [more ▼]

Zinc oxide (ZnO) nanostructures have been synthesized by a simple controlled precipitation method to study the effects of the type solvent – including water, acetic acid and ethylene glycol – on the formation of ZnO and on its photocatalytic activity for the decomposition of H2O2 in aqueous solution. Scanning electron microscopy (SEM) and synchrotron-based X-ray diffraction (XRD) were used to determine the morphology, crystallinity, and chemical composition of the ZnO structures. Raman spectroscopy and photoluminescence measurements were carried out to determine the nature of the defects present in the different ZnO nanostructures and how they affect the photocatalytic activity. Based on the results, we propose plausible growth mechanisms underlying the formation of ZnO with different morphology, according to the solvent used during the synthesis. A direct relation between the photocatalytic activity and the defects type was established, suggesting that defects play a vital role in modulating the photocatalytic response. [less ▲]

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See detailHighly Efficient Low-Temperature N-Doped TiO2 Catalysts for Visible Light Photocatalytic Applications
Mahy, Julien ULiege; Cerfontaine, Vincent; Poelman, Dirk et al

in Materials (2018), 11(584),

In this paper, TiO2 prepared with an aqueous sol-gel synthesis by peptization process is doped with nitrogen precursor to extend its activity towards the visible region. Three N-precursors are used: urea ... [more ▼]

In this paper, TiO2 prepared with an aqueous sol-gel synthesis by peptization process is doped with nitrogen precursor to extend its activity towards the visible region. Three N-precursors are used: urea, ethylenediamine and triethylamine. Different molar N/Ti ratios are tested and the synthesis is adapted for each dopant. For urea- and trimethylamine-doped samples, anatase-brookite TiO2 nanoparticles of 6–8 nm are formed, with a specific surface area between 200 and 275 m2·g−1. In ethylenediamine-doped samples, the formation of rutile phase is observed, and TiO2 nanoparticles of 6–8 nm with a specific surface area between 185 and 240 m2·g−1 are obtained. X-ray photoelectron spectroscopy (XPS) and diffuse reflectance measurements show the incorporation of nitrogen in TiO2 materials through Ti–O–N bonds allowing light absorption in the visible region. Photocatalytic tests on the remediation of water polluted with p-nitrophenol show a marked improvement for all doped catalysts under visible light. The optimum doping, taking into account cost, activity and ease of synthesis, is up-scaled to a volume of 5 L and compared to commercial Degussa P25 material. This up-scaled sample shows similar properties compared to the lab-scale sample, i.e., a photoactivity 4 times higher than commercial P25. [less ▲]

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See detailInteractions between Zn2+ or ZnO with TiO2 to produce an efficient photocatalytic, superhydrophilic and aesthetic glass
Léonard, Géraldine ULiege; Pàez Martinez, Carlos ULiege; Ramirez, Alfonso et al

in Journal of Photochemistry and Photobiology A: Chemistry (2018), 350

Zinc was coupled with titanium dioxide using different methods. SiO2 and Zn-SiO2 doped TiO2 films, on the one hand, and Zn doped TiO2 on the other hand, have been produced using controlled sol-gel ... [more ▼]

Zinc was coupled with titanium dioxide using different methods. SiO2 and Zn-SiO2 doped TiO2 films, on the one hand, and Zn doped TiO2 on the other hand, have been produced using controlled sol-gel processes by alcoholic, cogelation and aqueous ways. From these syntheses, films were deposited on soda lime glass. These samples were compared to ZnO samples but also to bilayer samples constituting one layer of TiO2 and one layer of ZnO. The physico-chemical properties of the films were characterized by grazing-incidence X-ray diffraction, profilometry and UV-Vis absorption analyses. The photocatalytic activity has been evaluated from the degradation of methylene blue under UV-A light, from the degradation of p-nitrophenol under visible light and from the degradation of H2O2 under halogen light (UV-A + visible light). Superhydrophilicity was evaluated from contact angle measurement after UV exposition and also from hysteresis effects. Finally, a haze measurement was performed to evaluate the impact of the coating on the aesthetic property of the coated glass. Aqueous films have better photocatalytic activity and superhydrophilicity than samples from alcoholic synthesis. The crystallization of the sample appears to be one key factor: alcoholic films required calcination to ensure the crystallization of TiO2, but the alkali migration from the glass support prevents this crystallisation, while aqueous synthesis promotes crystallized particles at low temperatures without alkali interference. It appears that the relative activity from one sample to another depends on the nature of the illumination and on the nature of the molecule to be degraded. Nevertheless, the sample with ZnO layer deposited on first TiO2 layer (ZnO 500 Alc/TiO2 100 AQ) composite is found to be the best sample, maintaining a high hydrophilicity similar to TiO2 and a good activity. [less ▲]

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See detailAdvanced oxidative treatment for waste water contamined by pharmaceutical products
Belet, Artium ULiege; Vreuls, Christelle; Gillard, Nathalie et al

Poster (2017, September 07)

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See detailSilica-based thin film solid-state electrolytes for Lithium-ion microbatteries
Hartmann, Korina ULiege; Calberg, Cédric ULiege; Liquet, Dimitri ULiege et al

Scientific conference (2017, September)

The emerging market of the Internet of Things, smart objects, wearables and others increase the demand for micro energy sources. Rechargeable lithium-ion batteries are a well-known technology for energy ... [more ▼]

The emerging market of the Internet of Things, smart objects, wearables and others increase the demand for micro energy sources. Rechargeable lithium-ion batteries are a well-known technology for energy storage. However, safety issues and high production costs constrain progress. Electrolyte solution based on ILs with dissolved lithium salt can be confined into inorganic porous networks forming so-called ionogels, which are investigated as solid electrolyte [1]. Ionogels combine low hazard and good ionic conductivity. However, the growth of lithium dendrites may be observed during cycling, which reduce battery lifetime. In this project, we try to prepare a silica-ionogel to prevent dendritic growth by mechanical hindrance. The ionogel composition and the influence of trifluoroacetic acid (TFA) as catalyst were studied to obtain a fast condensation of the silica precursor. [less ▲]

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See detailVisible-light TiO2 photocatalyst doped with silylated porphyrin
Mahy, Julien ULiege; Pàez Martinez, Carlos ULiege; Léonard, Géraldine ULiege et al

Conference (2017, August 15)

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See detailHighly efficient doped nanocristalline TiO2 for water Treatment
Mahy, Julien ULiege; Léonard, Géraldine ULiege; Zubiaur, Anthony ULiege et al

Conference (2017, July 13)

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See detailAdvanced oxidative treatment for waste water contamined by pharmaceutical products
Belet, Artium ULiege; Vreuls, Christelle; Gillard, Nathalie et al

Conference (2017, July 07)

The objective of this study is to determine operational processes for advanced oxidative treatment of waste waters contaminated with Pharmaceutical Products (PPs). The aim is to validate a physico ... [more ▼]

The objective of this study is to determine operational processes for advanced oxidative treatment of waste waters contaminated with Pharmaceutical Products (PPs). The aim is to validate a physico-chemical process combining ozonation and photocatalysis and that has to be placed downstream a classical biological treatment in existing waste water treatment plants (WWTP - domestic, industrial or hospital). [less ▲]

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