References of "Heinrichs, Benoît"
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See detailAqueous sol-gel synthesis and film deposition methods for the large-scale manufacture of coated steel with self-cleaning properties
Mahy, Julien ULg; Léonard, Géraldine ULg; Pirard, Sophie ULg et al

in Journal of Sol-Gel Science and Technology (in press)

A process has been developed to enable the large scale production of pure TiO2 films deposited on 316L stainless steel in order to get an easy-to-clean surface. This large scale process requires an easy ... [more ▼]

A process has been developed to enable the large scale production of pure TiO2 films deposited on 316L stainless steel in order to get an easy-to-clean surface. This large scale process requires an easy aqueous sol-gel procedure for the synthesis of the TiO2 sol. This synthesis has been simplified to facilitate the extrapolation towards an industrial scale. Results of TEM, photocatalytic properties, film hydrophilicity, and texture obtained with the simplified aqueous sol-gel synthesis (IsoP-TiO2 synthesis) show similar properties to those obtained with the standard aqueous sol-gel synthesis of TiO2 (HAc-TiO2 synthesis) developed previously. Only X-Ray Diffraction patterns showed differences, with the presence of anatase-brookite phases in IsoP-TiO2 synthesis while anatase phase only was observed in HAc-TiO2 synthesis. Both the aqueous sol-gel synthesis of pure TiO2 and the film deposition on steel by roll-coating have been successfully extrapolated to a larger scale. The photocatalytic activity and the hydrophilicity of the film were found to be unchanged when compared to films produced at a laboratory scale, thus validating the production of an efficient easy-to-clean material. Although some problems are still to be solved, this study is a hopeful first step in the development of a large scale process for self-cleaning steel production. [less ▲]

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See detailTowards a large scale aqueous sol-gel synthesis of doped TiO2: Study of various metallic dopings for the photocatalytic degradation of p-nitrophenol
Mahy, Julien ULg; Lambert, Stéphanie ULg; Léonard, Géraldine ULg et al

in Journal of Photochemistry and Photobiology A : Chemistry (2016), 329

In this paper, an easy aqueous sol-gel synthesis developed previously by Mahy et al. [J. Sol-Gel Sci. Technol. (2016)] is adapted to produce highly active TiO2 catalysts doped with Fe3+, Ag+, Cu2+, Zn2 ... [more ▼]

In this paper, an easy aqueous sol-gel synthesis developed previously by Mahy et al. [J. Sol-Gel Sci. Technol. (2016)] is adapted to produce highly active TiO2 catalysts doped with Fe3+, Ag+, Cu2+, Zn2+, Cr3+, Al3+, Mn2+, and Co2+ ions and Pt metallic nanoparticles. Samples are characterized by inductively coupled plasma–atomic emission spectroscopy (ICP-AES), X-ray diffraction (XRD), Mössbauer spectroscopy, transmission electron microscopy (TEM), nitrogen adsorption–desorption measurements and diffuse reflectance spectroscopy measurements. Results show that the samples are composed of anatase-brookite TiO2 nanoparticles with a spherical shape and mean diameter of around 5-8 nm and a surface area of between about 150 - 250 m2 g-1. In each doped sample, the dopant is present in the form added during the synthesis, given that the sample has not undergone any particular treatment. Photoactivity tests show improvement in catalyst activity for Fe3+, Ag+, Cu2+, Zn2+, and Al3+ ion and Pt metallic nanoparticle dopants, while a decrease of activity is obtained for Cr3+, Mn2+ and Co2+ ion dopants. For some dopants, the activity of TiO2 doped with metallic ions and synthesized from the aqueous sol-gel process is equal or superior to the activity of the commercial photocatalyst Degussa P25. Some mechanisms are proposed to explain these modifications of activity with doping. Furthermore, cost comparison at laboratory scale showed that Zn and Cu nitrate salt dopings are clearly less expensive for a halogen light (UV/visible) or low energy light enhanced catalyst and may be considered for industrial applications. Using this method, a large scale Zn-doped TiO2 photocatalyst is synthesized with properties homologous to the lab-scale product. Results show that the aqueous sol-gel synthesis developed previously can be easily adapted for doping in order to produce an up-scalable synthesis. [less ▲]

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See detailCatalytic reforming of biomass gasification tars with bi- or tri-doped catalysts optimized with organosilane precursors
Claude, Vincent ULg; Courson, Claire; Heinrichs, Benoît ULg et al

Conference (2016, June 08)

The thermochemical method called “biomass gasification” is generating emphatic interest for the production of bio-Syngas (CO + H2) since this process presents the advantage of being renewable without ... [more ▼]

The thermochemical method called “biomass gasification” is generating emphatic interest for the production of bio-Syngas (CO + H2) since this process presents the advantage of being renewable without emitting CO2. However, in practical applications, there are still some technical problems due to high tars concentration in the outlet gas which can condensate and clog the pipes. Many studies have highlighted the fact that the tar elimination via catalytic reforming seem to be the more practical and economical solution. The required properties of the catalysts are determined by its location: inside the reactor (primary catalyst) or outside of the reactor (secondary catalyst). Primary catalysts are generally robust, non-toxic, cheap and they are almost uniquely destined to fluidized bed reactors. Secondary catalysts can be used at the exit of both fluidized and fixed bed reactors. They are characterized by a tailored mesoporous shape, a controlled active site dispersion and an adapted elemental composition [1]. In this work , we decided to focus on designing materials for secondary catalytic applications, i.e. working at relatively low temperature (~650°C) with no mechanical stress. The supports were made of γ-Al2O3 synthesized via an easy Sol-Gel method. During their synthesis, these supports were doped with 10%wt of nickel and various combinations of metallic dopants (Co, Cu, Fe, Mn, Mo) in the aim of enhancing their catalytic activities and lifetime. [less ▲]

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See detailDevelopment of an easy aqueous sol-gel synthesis for large-scale film deposition methods for the manufacture of coated steel with self-cleaning properties
Mahy, Julien ULg; Léonard, Géraldine ULg; Pirard, Sophie ULg et al

Conference (2016, May 20)

In this work, a global process has been developed to produce at a large scale pure TiO2 films deposited on steel in order to get an easy-to-clean surface. This large scale process implies an easy aqueous ... [more ▼]

In this work, a global process has been developed to produce at a large scale pure TiO2 films deposited on steel in order to get an easy-to-clean surface. This large scale process implies an easy aqueous sol-gel process for the synthesis of the TiO2 sol. This synthesis [1] has been simplified to make easier the extrapolation towards an industrial scale. Results of TEM, photocatalytic properties, film hydrophilicity, and texture obtained with the simplified aqueous sol-gel synthesis (IsoP-TiO2 synthesis) show similar properties than those obtained with the standard aqueous sol-gel synthesis of TiO2 developed previously (HAc-TiO2 synthesis [2]). Only XRD patterns were slightly different with the presence of anatase-brookite phases in IsoP-TiO2 synthesis while anatase phase only was observed in HAc-TiO2 synthesis. Both the aqueous sol-gel synthesis of pure TiO2 and the film deposition on steel by roll-coating have been successfully extrapolated to a larger scale. Indeed, the deposition was done on a pilot line, the steel substrate is 25 cm width, and the band length is 800 m. The coating was deposited at line speed ranging from 30 to 120 m.min-1.The photocatalytic activity and the hydrophilicity of the film were found to be unchanged compared to the films produced at a laboratory scale, thus validating the production of an efficient easy-to-clean material. Even if some problems have still to be solved, this study is a hopeful first step in the development of a large scale process for self-cleaning steel production. [1] S. Mahshid, M. Askari, M.S. Ghamsari, J. Mater. Process. Technol. 189 (2007) 296–300 [2] C.M. Malengreaux, S. Douven, D. Poelman, B. Heinrichs, J.R. Bartlett, J. Sol-Gel Sci. Technol. 71 (2014) 557–570 [less ▲]

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See detailTailoring γ-Al2O3 supports with specific silicon precursors
Claude, Vincent ULg; Vilaseca, Miriam; Heinrichs, Benoît ULg et al

Poster (2016, May 13)

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See detailNon-isocyanate polyurethanes from carbonated soybean oil Using monomeric or oligomeric diamines To achieve thermosets or thermoplastics
Poussard, Loïc; Mariage, J.; Grignard, Bruno ULg et al

in Macromolecules (2016), 49(6), 2162-2171

Fully bio- and CO2-sourced non-isocyanate polyurethanes (NIPUs) were synthesized by reaction of carbonated soybean oil (CSBO) either with biobased short diamines or amino-telechelic oligoamides derived ... [more ▼]

Fully bio- and CO2-sourced non-isocyanate polyurethanes (NIPUs) were synthesized by reaction of carbonated soybean oil (CSBO) either with biobased short diamines or amino-telechelic oligoamides derived from fatty acids to achieve respectively thermoset or thermoplastic NIPUs. Biobased carbonated vegetable oils were first obtained by metal-free coupling reactions of CO2 with epoxidized soybean oils under supercritical conditions (120 °C, 100 bar) before complete characterization by FTIR, 1H NMR, and electrospray ionization mass spectroscopy (ESI-MS). In a second step, biobased NIPUs were produced by melt-blending of the so-produced cyclocarbonated oil with the biobased aminated derivatives. The thermal and mechanical properties of resulting polymers were found to be depending on the cyclocarbonated vegetable oil/amine ratio. More precisely, short diamines and CSBO led to the formation of cross-linked NIPUs, and the resulting tensile and thermal properties were poor. In contrast, elastomeric NIPUs derived from oligoamides and CSBO exhibited a better rigidity, an improved elongation at break (εr up to 400%), and a higher thermal stability (T95 wt% > 350 °C) than those of starting oligoamides. These results are impressive and highlight the potentiality of this environmental friendly approach to prepare renewable NIPU materials of high performances. [less ▲]

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See detailDoping TiO2 films with carbon nanotubes to simultaneously optimise antistatic, photocatalytic and superhydrophilic properties
Léonard, Géraldine ULg; Remy, Simon; Heinrichs, Benoît ULg

in Journal of Sol-Gel Science and Technology (2016)

Pure and multiwall carbon nanotube (MWCNT)- doped titanium dioxide (TiO2) films, synthesised from two sol–gel routes (alcoholic and aqueous) and deposited by dipcoating on glass, have been developed as ... [more ▼]

Pure and multiwall carbon nanotube (MWCNT)- doped titanium dioxide (TiO2) films, synthesised from two sol–gel routes (alcoholic and aqueous) and deposited by dipcoating on glass, have been developed as conductive, photocatalytic and superhydrophilic materials. While already crystallised in anatase structure at low temperature when synthesised in water, samples prepared in alcohol are amorphous. Their crystallisation in air has been studied at increasing temperatures. Effective incorporation of functionalised MWCNTs is confirmed in both aqueous and alcoholic samples with a closer interaction with TiO2 particles in the case of aqueous synthesis. In alcoholic samples, 400 C seems to be an optimised calcination temperature since 300 C does not allow crystallisation into anatase and 500 C removes MWCNTs through burning. The purpose of MWCNT doping is to obtain coatings that exhibit easy-toclean or self-cleaning properties. This can be achieved through an optimised combination of electrical conductivity (for antistatic property), photoactivity and superhydrophilicity. These three properties require the crystallisation of TiO2 into anatase. MWCNT doping dramatically increases both conductivity and photocatalytic activity, especially in alcoholic samples for the former and in aqueous samples for the latter. On the other hand, MWCNT introduction does not significantly affect the (super)hydrophilicity of films, which depends solely on the crystallinity of TiO2. [less ▲]

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See detailOverview of Superhydrophilic, Photocatalytic and Anticorrosive Properties of TiO2 Thin Films Doped with Multi-walled Carbon Nanotubes and Deposited on 316L Stainless Steel
Léonard, Géraldine ULg; Remy, Simon; Heinrichs, Benoît ULg

in Materials Today: Proceedings (2016, February), 3(2), 434-438

TiO2 films with MWCNTs are produced for anticorrosive applications to increase the lifetime of steel materials. TiO2 has two additional properties, photoactivity and superhydrophilicity. Two TiO2 samples ... [more ▼]

TiO2 films with MWCNTs are produced for anticorrosive applications to increase the lifetime of steel materials. TiO2 has two additional properties, photoactivity and superhydrophilicity. Two TiO2 samples, synthesized in aqueous or alcoholic media, have been doped with MWCNTs. The material which best combines anticorrosive, superhydrophilic and photocatalytic properties, is the one produced in aqueous medium (Aq-TiO2-CNT). Doping with MWCNTs increases the photodegradation of p-nitrophenol from 18% to 50%. MWCNTs allow to reduce the corrosion current and the corrosion potential. The good superhydrophilicity of TiO2 is kept on stainless steel with a contact angle after illumination around 5°. [less ▲]

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See detailCharacterization of photoactive coatings of SiO2 nanoparticles and Rose Bengal onto glass surfaces
Mendoza Gallego, Carlos ULg; Lismont, Marjorie ULg; Pàez Martinez, Carlos ULg et al

Conference (2016)

The fluorescence emission and singlet oxygen (1O2) production have been widely investigated over the last decade due to high-value added applications such as organic chemical synthesis1, wastewater ... [more ▼]

The fluorescence emission and singlet oxygen (1O2) production have been widely investigated over the last decade due to high-value added applications such as organic chemical synthesis1, wastewater treatment2 or photodynamic cancer therapy3. This work is dedicated to the synthesis and deposition of SiO2 nanoparticles on glass surfaces using Stober’s process and dip coating, respectively. The adherence was improved through the incorporation of different concentrations of these nanoparticles into a TiO2 matrix. Additionally, the speed of dip coating was used to modify SiO2 thicknesses. Rose bengal was covalently anchored to SiO2 coatings through (3-aminopropyl)triethoxysilane (APTES) linker. UV, IR, fluorescence, SEM and profilometry were used to characterize the corresponding films and the efficiency for singlet oxygen production was measured by oxidation of the amino acid methionine. The immobilization of SiO2 nanoparticles photosensitized with rose bengal showed promising results for the production of singlet oxygen. [less ▲]

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See detailNanostructured catalysts from sol-gel process for environmental purposes
Heinrichs, Benoît ULg

Scientific conference (2016)

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See detailEfficient P- and Ag-doped titania for the photocatalytic degradation of waste water organic pollutants
Bodson, Céline ULg; Heinrichs, Benoît ULg; Tasseroul, Ludivine ULg et al

in Journal of Alloys & Compounds (2016), 682

In this work, physico-chemical properties and photocatalytic activity of three types of dried or dried and calcined TiO2 materials, synthesized by the cogelation method, were studied: (i) a pure TiO2 ... [more ▼]

In this work, physico-chemical properties and photocatalytic activity of three types of dried or dried and calcined TiO2 materials, synthesized by the cogelation method, were studied: (i) a pure TiO2 xerogel ; (ii) TiO2 xerogels doped with Ag ; (iii) TiO2 xerogels co-doped with Ag and P. The presence of silver nanoparticles was observed by transmission electron microscopy (TEM) and the oxidation state of silver after calcination was examined by temperature-programmed reduction (TPR) measurements. The physico-chemical properties of xerogels were characterized by X-ray diffraction (XRD), diffuse reflectance UV-Vis spectroscopy (DR UV-Vis) and from nitrogen adsorption-desorption isotherms. The photocatalytic activity of the samples was quantified for the p-nitrophenol degradation under visible light. [less ▲]

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See detailProtoporphyrin IX Functionalised AgSiO2 Core-shell Nanoparticle: Plasmonic Enhancement of Fluorescence and Singlet Oxygen Production
Lismont, Marjorie ULg; Dreesen, Laurent ULg; Heinrichs, Benoît ULg et al

in Photochemistry & Photobiology (2016), 92

Metal-enhanced processes arising from the coupling of a dye with metallic nanoparticles (NPs) have been widely reported. However, few studies have simultaneously investigated these mechanisms from the ... [more ▼]

Metal-enhanced processes arising from the coupling of a dye with metallic nanoparticles (NPs) have been widely reported. However, few studies have simultaneously investigated these mechanisms from the viewpoint of dye fluorescence and photoactivity. Herein, protoporphyrin IX (PpIX) is grafted onto the surface of silver core silica shell NPs in order to investigate the effect of silver (Ag) localized surface plasmon resonance (LSPR) on PpIX fluorescence and PpIX singlet oxygen (1O2) production. Using two Ag core sizes, we report a systematic study of these photophysical processes as a function of silica (SiO2) spacer thickness, LSPR band position and excitation wavelength. The excitation of Ag NP LSPR, which overlaps the PpIX absorption band, leads to the concomitant enhancement of PpIX fluorescence and 1O2 production independently of the Ag core size, but in a more pronounced way for larger Ag cores. These enhancements result from the increase in the PpIX excitation rate through the LSPR excitation and decrease when the distance between PpIX and Ag NPs increases. A maximum fluorescence enhancement of up to 14-fold, together with an increase in photogenerated 1O2 production of up to five times are obtained using 100 nm Ag cores coated with a 5 nm thick silica coating. [less ▲]

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See detailDoped sol–gel films vs. powders TiO2: On the positive effect induced by the presence of a substrate
Léonard, Géraldine ULg; Malengreaux, Charline; Melotte, Quentin et al

in Journal of Environmental Chemical Engineering (2016), 4

SiO2 and Ag–SiO2 doped TiO2 films and powders have been produced using a controlled sol–gel process. The dopant has been introduced using an alkoxysilane-functionalized ligand, with or without complexed ... [more ▼]

SiO2 and Ag–SiO2 doped TiO2 films and powders have been produced using a controlled sol–gel process. The dopant has been introduced using an alkoxysilane-functionalized ligand, with or without complexed silver ions. The influence of dopants on physico-chemical properties of the catalysts is studied by XRD, TEM–EDX, DRUV–vis analyses in the case of powders, while GIXRD, XPS, profilometry, UV–vis absorption analyses have been used for thin films. The photocatalytic activity has been evaluated from the degradation of methylene blue under UV-A light in the presence of the different catalysts over a period of 24 h. The detailed comparison between powders and films highlights a surprising positive effect in the case of films due to the presence of the substrate. In the case of photocatalytic powders, the presence of SiO2 or Ag–SiO2 into the TiO2 matrix has a detrimental effect on the photocatalytic activity while the opposite tendency is observed in the case of films, with best activities obtained with Ag–SiO2 doping. Different factors, in particular crystallinity modification between powders and films, have been studied to explain these opposite behaviors. In the case of powders, crystallization is hindered by SiO2 and Ag particles incorporation into the TiO2 matrix, leading to a decrease of the photocatalytic activity. In the case of thin films, probably because of the presence of a substrate, crystallization is not influenced by the presence of SiO2 and Ag particles. Therefore, the latter ones can fully play their role of electron traps leading to an enhanced photocatalytic activity. [less ▲]

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See detailPhotocatalytic decomposition of hydrogen peroxide over nanoparticles of TiO2 and Ni(II)-porphyrin doped TiO2: a relationship between activity and porphyrin anchoring mode
Tasseroul, Ludivine ULg; Pàez Martinez, Carlos ULg; Lambert, Stéphanie ULg et al

in Applied Catalysis B : Environmental (2016), 182

The nickel tetra(4-carboxyphenyl)porphyrin (TCPPNi) was chimisorbed on Degussa P25 TiO2 at different concentrations. Diffuse reflectance spectroscopy in the UV/vis region, Fourier transform infrared ... [more ▼]

The nickel tetra(4-carboxyphenyl)porphyrin (TCPPNi) was chimisorbed on Degussa P25 TiO2 at different concentrations. Diffuse reflectance spectroscopy in the UV/vis region, Fourier transform infrared spectroscopy and thermal gravimetry combined with differential scanning calorimetry measurements allowed the determination of the TCPPNi anchoring mode. At low TCPPNi concentrations, this anchoring on Degussa P25 TiO2 took place through all four carboxylic groups, while at higher concentrations the anchoring occurred through one or two carboxylic groups. For the firsttime,the effect of UV/vis light irradiation on the H2O2-degradation activity of TiO2 and TCPPNi-doped TiO2 was studied using the method of following the production of O2 by gas pressure monitoring. The activity of seven different catalysts was related to the TCPPNi anchoring mode and the percentage of TiO2 Degussa P25 coverage. An optimum degradation of H2O2 was observed for 0.0115 mol TCPPNi × g−1 P25. In that case, the TCPPNi was anchored through the four carboxylic groups, corresponding to a strong interaction with Degussa P25 TiO2. Moreover, the TCPPNi did not cover the surface completely, therefore allowing the light to reach and activate the TiO2. [less ▲]

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See detailDegradation of p-nitrophenol and bacteria with TiO2 xerogels sensitized in situ with tetra(4-carboxyphenyl)porphyrins
Tasseroul, Ludivine ULg; Lambert, Stéphanie ULg; Eskenazi, David et al

Poster (2015, September 10)

Heterogeneous photocatalysis is widely studied for environmental applications as oxidative processes can completely destroy organic pollutants such as alkanes, pesticides, dyes, etc. and microorganisms ... [more ▼]

Heterogeneous photocatalysis is widely studied for environmental applications as oxidative processes can completely destroy organic pollutants such as alkanes, pesticides, dyes, etc. and microorganisms. The most used photocatalyst is the commercial TiO2 Degussa P25, which is composed of 80% anatase and 20% rutile and which is active when TiO2 is exposed to UV light ( < 380 nm). Recently, several studies have been performed to extend the light absorption range of TiO2 towards the visible range. In this study, TiO2-based materials doped with porphyrins, a widely used dye for the photosensibilization of TiO2, have been prepared using a sol-gel process. To stabilize the TiO2-dye interactions, free metal tetra(4-carboxyphenyl)porphyrin and nickel tetra(4-carboxyphenyl)porphyrin were introduced in situ into the TiO2 matrix during the sol-gel process rather than by grafting. Samples were thoroughly characterized by TEM, X-ray diffraction, FT-IR, DR-UV/Vis and their texture has been examined by nitrogen adsorption–desorption at 77 K. The photocatalytic activity for the degradation of p-nitrophenol and Escherichia coli and Lactobacillus rhamnosus bacteria cells in aqueous medium, under halogen lamp light have been evaluated in relation with the physico-chemical modifications induced by the doping. The low temperature vacuum drying protocol (150°C) used in the present study enabled to obtain porphyrin doped TiO2 xerogels with a high specific surface area, and containing nanoparticles composed of amorphous- and anatase-TiO2. Diffuse reflectance spectroscopy attest the presence of TCPPH2 and TCPPNi within the TiO2 matrix. In a first step, the photoactivity of the xerogels is tested for p-nitrophenol degradation. Results show that crystallinity and nature and concentration of porphyrin introduced in situ have major impact on the degradation performances. In a second step, the best xerogel for p-nitrophenol degradation has been used to degrade bacteria. This xerogel degrades E. coli and L. rhamnosus bacteria cells in less than 48 and 24 h respectively. The photocatalytic degradation of a pollutant is thus correlated to the degradation of bacteria since a xerogel doped with the TCPPNi degrades both p-nitrophenol, E. coli and L. rhamnosus. [less ▲]

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See detailPhotocatalytic Oxidative Treatment of Waste Water contamined with Pharmaceutical Products
Vreuls, Christelle; Wilmot, Annick; Cludts, Marc et al

Poster (2015, July)

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