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51. Properties of SBA-15 modified by iron nanoparticles as potential hydrogen adsorbents and sensors

Author

Abdelkrim Azzouz, R. Ouargli, R. Ben Slama, Saadia Nousir, and Nabil Bouazizi

Subjects
Hydrogen, Chemical polarity, Inorganic chemistry, Nanoparticle, chemistry.chemical_element, General Chemistry, Condensed Matter Physics, Hydrogen storage, Adsorption, chemistry, Desorption, General Materials Science, Dispersion (chemistry), Mesoporous material
Abstract

SBA-15-Fe was synthesized via the incorporation of Fe 0 nanoparticles (Fe(0)-Nps) in the mesoporous channels. Electron microscopy and X-ray diffraction showed that dispersion of fine iron NPs occurs mainly inside the channels of SBA-15, producing a slight structure compaction. This was accompanied by a significant improvement of both the affinity towards hydrogen and electrical conductivity, as supported by hydrogen adsorption tests and impedance measurements. CO 2 thermal programmed desorption measurements revealed an attenuation of the acid character of the solid surface. This was explained in terms of strong iron interaction with the lattice oxygen atoms that reduces the SiO–H bond polarity. The close vicinity of fine Fe(0)-Nps combined with the large pore size of SBA-15 appear to contribute to a synergistic improvement of the electrical conductivity. The results reported herein open new prospects for SBA-15 as potential adsorbents for hydrogen storage and carriers for hydrogen sensors. The use of iron in lieu of noble metals for designing such materials is a novelty, because such applications of iron-loaded silica have not been envisaged so far due to the high reactivity of iron towards air and water. The development of such technologies, if any, should address this issue.

Published
2015

52. Effect Of Synthesis Time On Structural, Optical And Electrical Properties Of CuO Nanoparticles Synthesized By reflux Condensation Method

Author

Nabil Bouazizi, A. Oueslati, R. Benslama, and R. Bargougui

Subjects
Aqueous solution, Materials science, Inorganic chemistry, Condensation, Oxide, Dielectric spectroscopy, chemistry.chemical_compound, Adsorption, Chemical engineering, chemistry, Phase (matter), General Materials Science, Spectroscopy, Monoclinic crystal system
Abstract

CuO nanopowder oxide was synthesized by reflux condensation method without any surfactants or templates, using copper nitrate in deionized water and aqueous ammonia solution. The structural, optical and electrical properties of the sample were investigated using X-ray diffraction (XRD), FT-IR, UV-visible spectroscopy and impedance spectroscopy measurements. The X-ray diffraction patterns revealed that CuO nanoparticles (NPs) was formed in pure monoclinic phase and good crystalline quality, whose NPs sizes were of the order 25 nm which an average size can be tailored by the synthesis time. FT-IR spectra of CuO NPs used to detect the possible adsorbed species on the CuO materials. In addition, the peaks at 529 and 604 cm -1

Published
2015

53. Cu

Author

Radia, Sennour, Tze Chieh, Shiao, Vasilica Alisa, Arus, M Nazir, Tahir, Nabil, Bouazizi, René, Roy, and Abdelkrim, Azzouz

Abstract

Copper-loaded organo-montmorillonite showed improved affinity towards hydrogen under ambient conditions. Clay ion exchange with a propargyl-ended cation followed by thiol-yne coupling with thioglycerol resulted in a porous structure with a 6 fold higher specific surface area, which dramatically decreased after copper incorporation. X-ray diffraction and photoelectron spectrometry, nuclear magnetic resonance (

Published
2017

54. Synthesis and properties of ZnO-HMD@ZnO-Fe/Cu core-shell as advanced material for hydrogen storage

Author

T. Boudharaa, R. Bargougui, Abdelkrim Azzouz, Salah Ammar, Nabil Bouazizi, Julien Vieillard, F. Le Derf, Chimie Organique et Bioorganique : Réactivité et Analyse (COBRA), Institut Normand de Chimie Moléculaire Médicinale et Macromoléculaire (INC3M), Institut de Chimie du CNRS (INC)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Université Le Havre Normandie (ULH), Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Institut de Chimie du CNRS (INC)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie Organique Fine (IRCOF), Université de Rouen Normandie (UNIROUEN), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Faculty of Sciences of Gabès, Université de Gabès, Interfaces, Traitements, Organisation et Dynamique des Systèmes (ITODYS (UMR_7086)), Université Paris Diderot - Paris 7 (UPD7)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Université du Québec à Montréal = University of Québec in Montréal (UQAM), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie Organique Fine (IRCOF), Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), and Université du Québec à Montréal (UQAM)

Subjects
Hydrogen, Nanoparticle, chemistry.chemical_element, 02 engineering and technology, 010402 general chemistry, 01 natural sciences, 7. Clean energy, Biomaterials, chemistry.chemical_compound, Hydrogen storage, Crystallinity, Colloid and Surface Chemistry, Surface modification, Organic chemistry, [CHIM]Chemical Sciences, Wurtzite crystal structure, Iron nanoparticles, 021001 nanoscience & nanotechnology, Hexamethylenediamine, 0104 chemical sciences, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, Dielectric spectroscopy, chemistry, Chemical engineering, Copper nanoparticles, 0210 nano-technology, Luminescence
Abstract

International audience; In this paper, a new synthetic strategy towards functionalized ZnO-HMD@ZnO-Fe/Cu core-shell using sol-gel process modified by chemical grafting of hexamethylenediamine (HMD) on the core and in-situ dispersion of Cu0/Fe0 as metallic nanoparticles (M-NPs) on the shell. The as-prepared core-shell materials were fully characterized by transmission electron microscopy, X-ray powder diffractometry, diffuse reflectance and FT-IR spectrophotometery, photoluminescence, and complexes impedance spectroscopy measurements. The XRD patterns agreed with that of the ZnO typical wurtzite structure, indicating good crystallinity of ZnO-HMD@ZnO-Fe/Cu, with the presence of Fe0 and Cu0 phases. Hexamethylenediamine grafting and M-NPs insertion were highly activated and enhanced the core and shell interface by the physiochemical interaction. After functionalization, luminescence intensities and electrical properties of both core and core-shell nanoparticles are improved, indicating the effects of the surface groups on the charge transfer of ZnO-HMD@ZnO-Fe/Cu. The hydrogen capacity retention was depended strongly on the composition and structure of the obtained core-shell. Iron/Copper-loaded ZnO-HMD@ZnO materials exhibited the highest capacity for hydrogen storage. The excellent stability and performance of the ZnO-HMD@ZnO-Fe/Cu core-shell make it an efficient candidate for hydrogen storage.

Published
2017

55. Chemical modification of the cocoa shell surface using diazonium salts

Author

R. Bargougui, Nabil Bouazizi, Nicolas Brun, Nadine Mofaddel, Flavia Fioresi, Emmanuel Djoufac Woumfo, Julien Vieillard, Patrick Nkuigue Fotsing, Franck Le Derf, Chimie Organique et Bioorganique : Réactivité et Analyse (COBRA), Institut Normand de Chimie Moléculaire Médicinale et Macromoléculaire (INC3M), Institut de Chimie du CNRS (INC)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Université Le Havre Normandie (ULH), Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Institut de Chimie du CNRS (INC)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie Organique Fine (IRCOF), Université de Rouen Normandie (UNIROUEN), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Faculty of Sciences of Gabès, and Université de Gabès

Subjects
food.ingredient, Spectrophotometry, Infrared, Cocoa husk, Salt (chemistry), 02 engineering and technology, 010402 general chemistry, Diazonium, 01 natural sciences, Husk, Lignin, Cocoa shell, Biomaterials, chemistry.chemical_compound, Colloid and Surface Chemistry, food, Organic chemistry, [CHIM]Chemical Sciences, chemistry.chemical_classification, Cacao, Grafting, Aryl, Food additive, Chemical modification, COCOA BEAN, Diazonium Compounds, 021001 nanoscience & nanotechnology, food.food, 0104 chemical sciences, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, chemistry, Microscopy, Electron, Scanning, 0210 nano-technology
Abstract

International audience; The outer portion of the cocoa bean, also known as cocoa husk or cocoa shell (CS), is an agrowaste material from the cocoa industry. Even though raw CS is used as food additive, garden mulch, and soil conditioner or even burnt for fuel, this biomass material has hardly ever been investigated for further modification. This article proposes a strategy of chemical modification of cocoa shell to add value to this natural material. The study investigates the grafting of aryl diazonium salt on cocoa shell. Different diazonium salts were grafted on the shell surface and characterized by infrared spectroscopy and scanning electronic microscopy imaging. Strategies were developed to demonstrate the spontaneous grafting of aryl diazonium salt on cocoa shell and to elucidate that lignin is mainly involved in immobilizing the phenyl layer.

Published
2017

56. Cu0-loaded SBA-15@ZnO with improved electrical properties and affinity towards hydrogen

Author

Abdelkrim Azzouz, F. Le Derf, S. Louhichi, Julien Vieillard, R. Bargougui, Nabil Bouazizi, R. Ouargli, Chimie Organique et Bioorganique : Réactivité et Analyse (COBRA), Institut Normand de Chimie Moléculaire Médicinale et Macromoléculaire (INC3M), Institut de Chimie du CNRS (INC)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Université Le Havre Normandie (ULH), Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Institut de Chimie du CNRS (INC)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie Organique Fine (IRCOF), Université de Rouen Normandie (UNIROUEN), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Faculty of Sciences of Gabès, Université de Gabès, and Université du Québec à Montréal = University of Québec in Montréal (UQAM)

Subjects
Materials science, Hydrogen, Band gap, General Physics and Astronomy, chemistry.chemical_element, Nanotechnology, 02 engineering and technology, 010402 general chemistry, Electrocatalyst, 01 natural sciences, Specific surface area, Surface properties, [CHIM]Chemical Sciences, Thermal stability, Band-gap, Hydrogen capture, Surfaces and Interfaces, General Chemistry, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 0104 chemical sciences, Surfaces, Coatings and Films, Cu0NPs, SBA-15, Chemical engineering, chemistry, Absorption band, ZnO, Crystallite, 0210 nano-technology, Dispersion (chemistry)
Abstract

International audience; A core-shell material was prepared using SBA-15 crystallites as cores for the growth of a ZnO shell, followed by Cu0 dispersion. The resulting Cu/SBA-15@ZnO nanostructure displayed higher specific surface area (SSA) and higher number of smaller pores as compared to the starting materials. Dispersion of fine Cu0NPs induced a compaction of the host matrice and a marked decay of the hydrophilic character, explained in terms of the involvement of terminal hydroxyl groups in competitive HO:Cu interaction at the expense of H-bridges with water. Heating at 400–450 °C seems to trigger ZnO dehydroxylation with possible self-polycondensation and/or the formation of Si-O-Zn bridges. This is an additional explanation of the significant SSA increase and decrease in the average pore diameter. Both ZnO and Cu0NP incorporation induced shifts in the UV–vis absorption band towards higher wavelengths, indicating a decrease in the optical band gap energy and an improvement of the conductance properties. As compared to ZnO, Cu0NPs produced stronger improvement of the conductance, which was found to increase with higher frequencies. Cu/SBA-15@ZnO also displayed higher affinity towards hydrogen as compared to SBA-15@ZnO and SBA-15 at ambient conditions. These outstanding properties combined to an appreciable thermal stability are worth to be prone to deeper investigations, because they can open promising prospects for Cu/SBA-15@ZnO as sensor, electrode material, electrocatalyst and/or hydrogen capture matrice.

Published
2017

57. Microwave-assisted polyol synthesis of mesoporous Ta doped mixed TiO 2 /SnO2 : Application for CO2 capture

Author

Salah Ammar, J.-F. Hochepied, R. Bargougui, Julien Vieillard, Nabil Bouazizi, F. Le Derf, Faculty of Sciences of Gabès, Université de Gabès, Chimie Organique et Bioorganique : Réactivité et Analyse (COBRA), Institut Normand de Chimie Moléculaire Médicinale et Macromoléculaire (INC3M), Institut de Chimie du CNRS (INC)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Université Le Havre Normandie (ULH), Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Institut de Chimie du CNRS (INC)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie Organique Fine (IRCOF), Université de Rouen Normandie (UNIROUEN), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Unité de Chimie et Procédés (UCP), École Nationale Supérieure de Techniques Avancées (ENSTA Paris), Centre des Matériaux (MAT), MINES ParisTech - École nationale supérieure des mines de Paris, and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Anatase, Materials science, Nanoparticle, Nanotechnology, 02 engineering and technology, Tantalum, 010402 general chemistry, 01 natural sciences, Mixed oxides, chemistry.chemical_compound, Physisorption, Phase (matter), Materials Chemistry, Triethylene glycol, Nanocomposite, Mechanical Engineering, Doping, Metals and Alloys, 021001 nanoscience & nanotechnology, CO2 capture, 0104 chemical sciences, chemistry, Chemical engineering, 13. Climate action, Mechanics of Materials, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], 0210 nano-technology, Mesoporous material, Microwave-assisted polyol
Abstract

International audience; Tantalum-decorated mixed oxides (Ti0.5Sn0.5O2) was successfully synthesized, using a microwave-assisted polyol process (MAP) and triethylene glycol as a solvent, in a much shorter time than conventional heating. The newly-synthesized nanocomposites materials were used to make resistive semiconductor gas sensors to detect CO2. The powders were investigated using X-ray diffractometry, transmission electron microscopy and N2 physisorption. The X-ray diffraction patterns of the samples confirm that TiO2 is in the anatase phase and SnO2 and Ti0.5Sn0.5O2 are in the cassiterite phase. The TEM images showed uniform isotropic morphologies with average sizes close to 10 nm. The optimized sensor, based on TiO2/SnO2/Ta showed promising performances towards CO2 capture, ensuring a high response and fast dynamics at an operating temperature of 20 °C. The CO2 adsorption capacity was also remarkably increased from 0.58 mmol g−1 for TiO2 alone to 0.90 mmol g−1 for the Ti0.5Sn0.5O2. This work brings insights into a new way of limiting atmospheric pollution using mixed-oxide nanoparticles.

Published
2017

59. Synthesis of tin oxide activated by DAN grafting and Mo nanoparticle insertion for optoelectronic properties improvement

Author

Nabil Bouazizi, Abdelkrim Azzouz, Julien Vieillard, Salah Ammar, A. Benghnia, R. Bargougui, Chimie Organique et Bioorganique : Réactivité et Analyse (COBRA), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie Organique Fine (IRCOF), Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), Faculty of Sciences of Gabès, Université de Gabès, Interfaces, Traitements, Organisation et Dynamique des Systèmes (ITODYS (UMR_7086)), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), Université du Québec à Montréal (UQAM), Institut Normand de Chimie Moléculaire Médicinale et Macromoléculaire (INC3M), Institut de Chimie du CNRS (INC)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Université Le Havre Normandie (ULH), Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Institut de Chimie du CNRS (INC)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie Organique Fine (IRCOF), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Université Paris Diderot - Paris 7 (UPD7)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), and Université du Québec à Montréal = University of Québec in Montréal (UQAM)

Subjects
Materials science, Photoluminescence, medicine.diagnostic_test, General Chemical Engineering, Infrared spectroscopy, Nanoparticle, 02 engineering and technology, General Chemistry, 010402 general chemistry, 021001 nanoscience & nanotechnology, Tin oxide, 7. Clean energy, 01 natural sciences, 0104 chemical sciences, Chemical engineering, Spectrophotometry, medicine, Organic chemistry, [CHIM]Chemical Sciences, Crystallite, Fourier transform infrared spectroscopy, 0210 nano-technology, Spectroscopy
Abstract

International audience; Tin oxide (SnO2) was synthesized via a co-precipitation method and activated by 1,5 diaminonaphthalene (DAN) grafting and molybdenum nanoparticles (Mo-NPs) incorporation. The resulting SnO2–DAN–Mo nanocomposites were characterized by X-ray diffraction, transmission electron microscopy, diffuse reflectance and FTIR spectrophotometry, photoluminescence spectroscopy and complex impedance spectroscopy measurements. The surface-grafting of DAN within mesopores was confirmed by Fourier-transform infrared spectroscopy. The XRD and TEM studies showed a dominant tetragonal structure. The dispersion of fine Mo-NPs on the surface of the matrices, produced slight structural compaction. The crystallite size decreased with the insertion of DAN and Mo-NPs. The photoluminescence study revealed the presence of oxygen vacancies and that the PL intensity strongly depends on DAN grafting and Mo-NPs insertion. In addition, both the incorporation of Mo-NPs and DAN grafting appear to be responsible for the changes in the conductance and relaxation phenomenon. The effects of surface groups of SnO2–DAN–Mo and charge transfer were found to be almost proportional to the capacitance. The above properties make these nanocomposites efficient electrode materials for green energy storage.

Published
2016

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