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81 results on '"Izabela Janowska"'

1. Selenium nanoparticles synthesized using an eco-friendly method: dye decolorization from aqueous solutions, cell viability, antioxidant, and antibacterial effectiveness

Author: Badreah A. Al Jahdaly, Najlaa S. Al-Radadi, Ghada M.G. Eldin, Albandary Almahri, M.K. Ahmed, Kamel Shoueir, and Izabela Janowska
Subjects: SeNPs, Ascorbic acid, Dye removal, Antibacterial, Antioxidant, Mining engineering. Metallurgy, TN1-997
Abstract: Selenium nanoparticles (SeNPs) were fabricated using a green microwave technique in the presence of ascorbic acid. The morphological features indicated that the semi-spherical SeNPs with a diameter 8.5–22 nm were configured in agglomerated spherical shapes with diameters around 0.47–0.71 μm. Furthermore, the removal of Fuchsin Basic dye from aqueous solutions was investigated upon variation of concentration of SeNPs. The degradation efficiency achieved 100% for 10 mg of SeNPs after 34 min of visible light irradiation time. The antioxidant activity was tested via DPPH radical scavenging assay and displayed that the highest scavenging capacity (311.1 ± 15.72 mg/g) was achieved by SeNPs at a concentration of 106.25 mg/mL. Otherwise, the cell viability of SeNPs through human fibroblasts cell lines in-vitro was reduced to be 75.1 ± 3.8% with nanoparticle concentration around 500 μg/mL. The antibacterial activity was investigated against gram-negative and gram-positive bacteria such as Escherichia coli (E.coli), Pseudomonas aeruginosa (P. aeruginosa), Klebsiella pneumoniae (K. pneumonia), Staphylococcus aureus (S. aureus), and Bacillus subtilis (B. subtilis) bacteria after one day of exposure. It was illustrated that SeNPs did not display an activity towards Staphylococcus aureus, while it possessed the highest one against Escherichia coli with MBC of 50 ± 1.76 μg/mL compared with 26 ± 0.6 μg/mL for the standard antibiotic. These tremendous properties of SeNPs indicate that manipulating multifunctional nanoparticles for versatile wound and skin treatment applications is highly encouraging.
Published: 2021
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2. Fe Atom—Mixed Edges Fractal Graphene via DFT Calculation

Author: Lobna Aloui, Thierry Dintzer, and Izabela Janowska
Subjects: Fe-graphene, graphene edges, graphene defects, fractal, atom catalyst, Chemistry, QD1-999
Abstract: The stability of small fractal graphene models with two different symmetries and Fe atoms at their mixed edges is addressed by density functional theory (DFT) calculations. Four kinds of edge configurations and Fe atom localizations are determined depending on the model. The edges have mixed configuration, the zig-zag and “intra-zig-zag” in symmetrical structures and armchair and zig-zag type in the architectures with rotational symmetry. The rotational symmetry graphene exhibits slightly higher stability per carbon atom compared to the symmetrical model, while the localization of Fe atoms is more favorable at armchair and “inversed zigzag” than at zigzag type carbon termination. Larger graphene structures with rotational symmetry were observed previously via experimental cutting of graphene with Fe nanoparticles (NPs).
Published: 2022
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3. Colloid Approach to the Sustainable Top-Down Synthesis of Layered Materials

Author: Housseinou Ba, Lai Truong-Phuoc, Cuong Pham-Huu, Wen Luo, Walid Baaziz, Thierry Romero, and Izabela Janowska
Subjects: Chemistry, QD1-999
Published: 2017
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4. Polyvinyl Alcohol-Few Layer Graphene Composite Films Prepared from Aqueous Colloids. Investigations of Mechanical, Conductive and Gas Barrier Properties

Author: Benoit Van der Schueren, Hamza El Marouazi, Anurag Mohanty, Patrick Lévêque, Christophe Sutter, Thierry Romero, and Izabela Janowska
Subjects: nano composites, polymer-matrix composites, electrical properties, mechanical properties, few layer graphene composites, Chemistry, QD1-999
Abstract: Quasi all water soluble composites use graphene oxide (GO) or reduced graphene oxide (rGO) as graphene based additives despite the long and harsh conditions required for their preparation. Herein, polyvinyl alcohol (PVA) films containing few layer graphene (FLG) are prepared by the co-mixing of aqueous colloids and casting, where the FLG colloid is first obtained via an efficient, rapid, simple, and bio-compatible exfoliation method providing access to relatively large FLG flakes. The enhanced mechanical, electrical conductivity, and O2 barrier properties of the films are investigated and discussed together with the structure of the films. In four different series of the composites, the best Young’s modulus is measured for the films containing around 1% of FLG. The most significant enhancement is obtained for the series with the largest FLG sheets contrary to the elongation at break which is well improved for the series with the lowest FLG sheets. Relatively high one-side electrical conductivity and low percolation threshold are achieved when compared to GO/rGO composites (almost 10−3 S/cm for 3% of FLG and transport at 0.5% FLG), while the conductivity is affected by the formation of a macroscopic branched FLG network. The composites demonstrate a reduction of O2 transmission rate up to 60%.
Published: 2020
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5. Few-Layer Graphene from Mechanical Exfoliation of Graphite-Based Materials: Structure-Dependent Characteristics

Author: Azhar A. Pirzado, François Le Normand, Thierry Romero, Sandra Paszkiewicz, Vasiliki Papaefthimiou, Dris Ihiawakrim, and Izabela Janowska
Subjects: few-layer graphene, mechanical exfoliation, graphene nanocomposites, conductive layer, nuclear reaction analysis, Chemistry, QD1-999
Abstract: We present a high-scale method to produce few-layer graphene (FLG) based on the mechanical exfoliation of graphite and compare the obtained FLG with the one reported earlier arising from pencil lead ablation. Several elements were modified and improved in the new approach. The purification and the ablation set-up were simplified, and the morphology of the FLG was modified and improved in view of some applications. The morphology-dependent properties of FLGs, lead-FLG, and graphite-FLG as conductive layers and in nanocomposites were investigated. The newly obtained FLG had a higher aspect ratio (high lateral size vs thickness/higher 2D aspect), which is reflected by enhanced transparency–conductivity features of the layer (film) and elongation-at-break behavior of the polymer composites. On the contrary, the nanocomposite containing lead-FLG showed, for instance, excellent gas barrier properties due to the multi-step structure of the lead-FLG flakes. Such structure exhibited less 2D and more 3D character, which can be highly suitable for applications where the presence of active/reactive edges is beneficial, e.g., in catalysis or supercapacitors’ electrodes. Nuclear reaction analysis was employed to investigate the morphology of graphite-FLG film.
Published: 2019
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6. On the evolution of oxidative etching of few layer graphene (FLG) in FLG /TiO2 nanocomposites. Interfacial dipole signature and chemical shift in C1s X-ray photoemission spectra

Author: Hamza El Marouazi, Valérie Keller, Izabela Janowska, Institut de chimie et procédés pour l'énergie, l'environnement et la santé (ICPEES), Université de Strasbourg (UNISTRA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et Nanosciences Grand-Est (MNGE), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), This work was supported by the ANR program (PHOTER) and statutory CNRS/Unistra funding., and KELLER, Valérie
Subjects: Condensed Matter - Materials Science, TiO2 catalyst, Materials Science (cond-mat.mtrl-sci), FOS: Physical sciences, General Physics and Astronomy, Surfaces and Interfaces, General Chemistry, Condensed Matter Physics, Surfaces, Coatings and Films, Charge transfer, Interfacial dipole, [CHIM] Chemical Sciences, Xps, [CHIM]Chemical Sciences, Graphene edges, Oxidative etching
Abstract: We present the effect of oxidative etching in FLG/TiO$_2$ hybrids on FLG edges chemistry/morphology addressing also the catalytic activity of TiO$_2$ NPs. According to the XPS and TGA analysis the oxidation degree strongly depends on TiO$_2$:FLG ratio. The preparation of two series of FLG/TiO$_2$ hybrids via sol-gel method and in-situ oxidation permitted to correctly describe and distinguish the chemical composition, core shift and charge distribution in C1s XPS with Tip peak as reference. Such analysis is challenging in carbon materials due the overlapping of C1s peaks from the sample and adventitious carbon reference. We claim the formation of interfacial dipole as possible direct signature of charge transfer from TiO$_2$ to FLG. A downward shift of C1s (sp$^2$C) up to 1.4 eV is measured and contributions of non sp$^2$C are determined in the composites. The modifications related to the oxidation are supported by TEM/SEM observations, and referred to non-catalytic oxidation and oxidation in mechanically mixed components. KEYWORDS: oxidative etching, graphene edges, TiO$_2$ catalyst, interfacial dipole, XPS, charge transfer
Published: 2022
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7. Performant removal of creatinine using few-layer-graphene/alginate beads as a kidney filter

Author: Kamel Shoueir, Ahmed M. Wahba, Hamza El Marouazi, and Izabela Janowska
Subjects: Structural Biology, General Medicine, Molecular Biology, Biochemistry
Published: 2023
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8. Structural impact of carbon nanofibers/few-layer-graphene substrate decorated with Ni for CO2 methanation via inductive heating

Author: Anurag Mohanty, Cuong Duong Viet, Anne-Cécile Roger, Izabela Janowska, Walid Baaziz, Alexandre Adam, Damien Mertz, Institut de chimie et procédés pour l'énergie, l'environnement et la santé (ICPEES), Université de Strasbourg (UNISTRA)-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA), Centre National de la Recherche Scientifique (CNRS), Janowska, Izabela, Université de Strasbourg (UNISTRA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et Nanosciences Grand-Est (MNGE), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et Nanosciences Grand-Est (MNGE), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, and Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Materials science, Induction heating, Carbon nanofiber, Inductive Heating, Nanoparticle, chemistry.chemical_element, 02 engineering and technology, Chemical vapor deposition, 010402 general chemistry, 01 natural sciences, Catalysis, CO 2 methanation, Methanation, [CHIM] Chemical Sciences, [CHIM]Chemical Sciences, General Environmental Science, Ni catalysts, Process Chemistry and Technology, 021001 nanoscience & nanotechnology, 0104 chemical sciences, Few-layer-graphene, chemistry, Chemical engineering, 0210 nano-technology, Joule heating, Carbon
Abstract: International audience; The structure of catalyst containing Ni nanoparticles (NPs) supported over carbon nanofibers/few layer graphene (CNFs/FLG) was tailored via modification of chemical vapor deposition parameters in view of methanation of CO 2 under induction heating mode (IH). High edges-to-graphitic plane ratio in the support achieved due to the specific herringbone morphology of CNFs allowed to get high CO 2 conversion of 85% at relatively low temperature (360°C) at very low Ni loading of only 10%. A design of catalyst included also the use of FLG known for high temperature conductivity and by occasion serving as a support to grow CNFs. The performances of certain catalysts are also tested under "standard" Joule heating in order to check the role of the magnetic and conductive carbon support. The morphology, chemical composition and SAR measurements of the catalysts and carbon supports themselves are addressed and their structure-catalytic performances are discussed.
Published: 2021
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9. Industrial molasses waste in the performant synthesis of few-layer graphene and its Au/Ag nanoparticles nanocomposites. Photocatalytic and supercapacitance applications

Author: Kamel Shoueir, Anurag Mohanty, and Izabela Janowska
Subjects: Renewable Energy, Sustainability and the Environment, Strategy and Management, Building and Construction, Industrial and Manufacturing Engineering, General Environmental Science
Published: 2022
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10. Few Layer Graphene/TiO 2 Composites for Enhanced Solar-Driven H 2 Production from Methanol

Author: Izabela Janowska, Valérie Keller, Christophe Colbeau-Justin, Hamza El Marouazi, Pablo Jiménez-Calvo, Edouard Breniaux, Laboratoire de Physique des Solides (LPS), Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11), Centre interuniversitaire de recherche et d'ingenierie des matériaux (CIRIMAT), Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC), Laboratoire de Chimie Physique D'Orsay (LCPO), Université Paris-Sud - Paris 11 (UP11)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), and Centre National de la Recherche Scientifique (CNRS)
Subjects: Materials science, General Chemical Engineering, Oxide, 02 engineering and technology, 010402 general chemistry, 7. Clean energy, 01 natural sciences, law.invention, chemistry.chemical_compound, law, Environmental Chemistry, [CHIM]Chemical Sciences, Composite material, [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat], ComputingMilieux_MISCELLANEOUS, [PHYS]Physics [physics], Renewable Energy, Sustainability and the Environment, Graphene, General Chemistry, 021001 nanoscience & nanotechnology, 0104 chemical sciences, Few layer graphene, chemistry, [SDE]Environmental Sciences, Photocatalysis, Methanol, 0210 nano-technology
Abstract: International audience; Here, the elaboration of few layer graphene/TiO2 photocatalytic composites (FLG/TiO2) with FLG loadings from 0.5 to 11 wt % is presented. Contrary to the commonly used (reduced) graphene oxide obtained by long and harsh condition synthesis, FLG was synthesized by a simple, fast, efficient, and eco-friendly exfoliation method. The enhancement of defective/functionalized site density for the attachment of TiO2 species was achieved via the calcination process at 450 °C. The nanocomposites were evaluated toward H2 production from methanol under artificial solar light irradiation, without the use of a co-catalyst. It was observed that the best activities are provided by the composites with the lowest loading: 0.5 and 1.0 wt % FLG/TiO2 that are 2–3 times more efficient than reference and commercial TiO2. The photocatalytic activity of the composites was correlated to their surface area, morphological, structural, optical properties, and kinetics of free electron mobility properties. The enhanced activity is attributed to a higher surface area, better photogenerated charge separation thanks to electrons’ delocalization and trapping onto graphene layers well interfaced with TiO2 nanoparticles but also to additional FLG visible light absorption properties and charge carriers’ generation. The impact of enhanced FLG edge defects/functionalities is reflected as well via selected analysis and hydrogen generation.
Published: 2021
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11. Selenium nanoparticles synthesized using an eco-friendly method: dye decolorization from aqueous solutions, cell viability, antioxidant, and antibacterial effectiveness

Author: Kamel R. Shoueir, M.K. Ahmed, Badreah A. Al Jahdaly, Najlaa S. Al-Radadi, Izabela Janowska, Albandary Almahri, Ghada M.G. Eldin, Institut de chimie et procédés pour l'énergie, l'environnement et la santé (ICPEES), Université de Strasbourg (UNISTRA)-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Umm Al-Qura University, Taibah University, National Organization for Drug Control and Research (NODCAR), King Khalid University [Abha], Suez University, and Kafrelsheikh University
Subjects: lcsh:TN1-997, Antioxidant, Materials science, antioxidant, DPPH, medicine.medical_treatment, chemistry.chemical_element, 02 engineering and technology, medicine.disease_cause, 01 natural sciences, Biomaterials, chemistry.chemical_compound, 0103 physical sciences, medicine, [CHIM]Chemical Sciences, Viability assay, lcsh:Mining engineering. Metallurgy, ComputingMilieux_MISCELLANEOUS, 010302 applied physics, biology, Metals and Alloys, 021001 nanoscience & nanotechnology, biology.organism_classification, Ascorbic acid, Surfaces, Coatings and Films, dye removal, antibacterial, chemistry, Staphylococcus aureus, Ceramics and Composites, SeNPs, ascorbic acid, 0210 nano-technology, Antibacterial activity, Bacteria, Selenium, Nuclear chemistry
Abstract: International audience; Selenium nanoparticles (SeNPs) were fabricated using a green microwave technique in the presence of ascorbic acid. The morphological features indicated that the semi-spherical SeNPs with a diameter 8.5-22nm were configured in agglomerated spherical shapes with diameters around 0.47-0.71 μm. Furthermore, the removal of Fuchsin Basic dye from aqueous solutions was investigated upon variation of concentration of SeNPs. The degradation efficiency achieved 100 % for 10 mg of SeNPs after 34 min of visible light irradiation time. The antioxidant activity 2 was tested via DPPH radical scavenging assay and displayed that the highest scavenging capacity (311.115.72 mg/g) was achieved by SeNPs at a concentration of 106.25 mg/mL. Otherwise, the cell viability of SeNPs through human fibroblasts cell lines in-vitro was reduced to be 75.13.8 % with nanoparticle concentration around 500 μg/mL. The antibacterial activity was investigated against gram-negative and gram-positive bacteria such as Escherichia coli (E.coli), Pseudomonas aeruginosa (P. aeruginosa), Klebsiella pneumoniae (K. pneumonia), Staphylococcus aureus (S. aureus), and Bacillus subtilis (B. subtilis) bacteria after one day of exposure. It was illustrated that SeNPs did not display an activity towards Staphylococcus aureus, while it possessed the highest one against Escherichia coli with MBC of 50 ± 1.76 g/mL compared with 26 ± 0.6 g/mL for the standard antibiotic. These tremendous properties of SeNPs indicate that manipulating multifunctional nanoparticles for versatile wound and skin treatment applications is highly encouraging.
Published: 2021
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12. Chitosan based-nanoparticles and nanocapsules: Overview, physicochemical features, applications of a nanofibrous scaffold, and bioprinting

Author: M.K. Ahmed, Moataz M. Rashad, Kamel R. Shoueir, Nagwa El-Desouky, Izabela Janowska, Maged El-Kemary, Institut de chimie et procédés pour l'énergie, l'environnement et la santé (ICPEES), Université de Strasbourg (UNISTRA)-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Kafrelsheikh University, and Suez University
Subjects: Biocompatibility, chitosan nanofibers, Nanofibers, Nanotechnology, Biocompatible Materials, 02 engineering and technology, macromolecular substances, engineering.material, Biochemistry, Nanocapsules, Chitosan, 03 medical and health sciences, chemistry.chemical_compound, Drug Delivery Systems, Tissue engineering, Anti-Infective Agents, Structural Biology, [CHIM]Chemical Sciences, Molecular Biology, ComputingMilieux_MISCELLANEOUS, 030304 developmental biology, 0303 health sciences, Tissue Engineering, Tissue Scaffolds, technology, industry, and agriculture, General Medicine, 021001 nanoscience & nanotechnology, 3. Good health, chitosan production, the degree of deacetylation, chemistry, Solubility, Nanofiber, Polycaprolactone, Drug delivery, engineering, Nanoparticles, Biopolymer, chitosan physicochemical properties, 0210 nano-technology, bioprinting
Abstract: International audience; Recent advancements in the synthesis, properties, and applications of chitosan as the second after cellulose available biopolymer in nature were discussed in this review. A general overview of processing and production procedures from A to Z was highlighted. Chitosan exists in three polymorphic forms which differ in degree of crystallinity (α, β, and γ). Thus, the degree of deacetylation, crystallinity, surface area, and molecular mass significantly affect most applications. Otherwise, the synthesis of chitosan nanofibers is suffering from many drawbacks that were recently treated by co-electrospun with other polymers such as polyvinyl alcohol (PVA), polyethylene oxide (PEO), and polycaprolactone (PCL). Ultimately, this review focuses on the area of new trend utilization of chitosan nanoparticles as nanospheres and nanocapsules, in cartilage and bone regenerative medicine. Owing to its biocompatibility, bioavailability, biodegradability, and costless synthesis, chitosan is a promising biopolymeric structure for water remediation, drug delivery, antimicrobials, and tissue engineering.
Published: 2021
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13. Comparing Multi-Walled Carbon Nanotubes and Halloysite Nanotubes as Reinforcements in EVA Nanocomposites

Author: Anna Szymczyk, Sandra Paszkiewicz, Izabela Janowska, Agata Zubkiewicz, A. Kochmańska, Piotr Franciszczak, West Pomeranian University of Technology Szczecin, Centre National de la Recherche Scientifique (CNRS), Institut de chimie et procédés pour l'énergie, l'environnement et la santé (ICPEES), Université de Strasbourg (UNISTRA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et Nanosciences Grand-Est (MNGE), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Janowska, Izabela, Université de Strasbourg (UNISTRA)-Matériaux et nanosciences d'Alsace (FMNGE), and Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: EVA elastomers, Materials science, Scanning electron microscope, chemistry.chemical_element, FOS: Physical sciences, 02 engineering and technology, Carbon nanotube, engineering.material, mechanical properties, 010402 general chemistry, 01 natural sciences, Halloysite, lcsh:Technology, Article, law.invention, chemistry.chemical_compound, law, Ultimate tensile strength, carbon nanotubes (CNTs), nanocomposites, [CHIM] Chemical Sciences, [CHIM]Chemical Sciences, General Materials Science, halloysite nanotubes (HNTs), Composite material, lcsh:Microscopy, lcsh:QC120-168.85, chemistry.chemical_classification, Condensed Matter - Materials Science, Nanocomposite, lcsh:QH201-278.5, electrical conductivity, lcsh:T, thermal properties, Ethylene-vinyl acetate, Materials Science (cond-mat.mtrl-sci), Polymer, 021001 nanoscience & nanotechnology, 0104 chemical sciences, chemistry, lcsh:TA1-2040, engineering, lcsh:Descriptive and experimental mechanics, lcsh:Electrical engineering. Electronics. Nuclear engineering, 0210 nano-technology, lcsh:Engineering (General). Civil engineering (General), Carbon, lcsh:TK1-9971
Abstract: International audience; The influence of carbon multi-walled nanotubes (MWCNTs) and halloysite nanotubes (HNTs) on the physical, thermal, mechanical, and electrical properties of EVA (ethylene vinyl acetate) copolymer was investigated. EVA-based nanocomposites containing MWCNTs or HNTs, as well as hybrid nanocomposites containing both nanofillers were prepared by melt blending. Scanning electron microcopy (SEM) images revealed the presence of good dispersion of both kinds of nanotubes throughout the EVA matrix. The incorporation of nanotubes into the EVA copolymer matrix did not significantly affect the crystallization behavior of the polymer. The tensile strength of EVA-based nanocomposites increased along with the increasing CNTs (carbon nanotubes) content (increased up to approximately 40% at the loading of 8 wt.%). In turn, HNTs increased to a great extent the strain at break. Mechanical cyclic tensile tests demonstrated that nanocomposites with hybrid reinforcement exhibit interesting strengthening behavior. The synergistic effect of hybrid nanofillers on the modulus at 100% and 200% elongation was visible. Moreover, along with the increase of MWCNTs content in EVA/CNTs nanocomposites, an enhancement in electrical conductivity was observed.
Published: 2020
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14. Polyvinyl Alcohol-Few Layer Graphene Composite Films Prepared from Aqueous Colloids. Investigations of Mechanical, Conductive and Gas Barrier Properties

Author: Anurag Mohanty, Patrick Lévêque, Benoit Van der Schueren, Thierry Romero, Christophe Sutter, Hamza El Marouazi, Izabela Janowska, Institut de chimie et procédés pour l'énergie, l'environnement et la santé (ICPEES), Université de Strasbourg (UNISTRA)-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire des sciences de l'ingénieur, de l'informatique et de l'imagerie (ICube), Institut National des Sciences Appliquées - Strasbourg (INSA Strasbourg), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-École Nationale du Génie de l'Eau et de l'Environnement de Strasbourg (ENGEES)-Réseau nanophotonique et optique, Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Janowska, Izabela, Université de Strasbourg (UNISTRA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et Nanosciences Grand-Est (MNGE), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), École Nationale du Génie de l'Eau et de l'Environnement de Strasbourg (ENGEES)-Université de Strasbourg (UNISTRA)-Institut National des Sciences Appliquées - Strasbourg (INSA Strasbourg), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National de Recherche en Informatique et en Automatique (Inria)-Les Hôpitaux Universitaires de Strasbourg (HUS)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et Nanosciences Grand-Est (MNGE), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, and Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Materials science, General Chemical Engineering, Composite number, Oxide, FOS: Physical sciences, nano composites, 02 engineering and technology, Conductivity, mechanical properties, 010402 general chemistry, polymer-matrix composites, 01 natural sciences, Polyvinyl alcohol, Article, law.invention, lcsh:Chemistry, chemistry.chemical_compound, Colloid, law, [CHIM] Chemical Sciences, [CHIM]Chemical Sciences, General Materials Science, Condensed Matter - Materials Science, Graphene, few layer graphene composites, Materials Science (cond-mat.mtrl-sci), Percolation threshold, 021001 nanoscience & nanotechnology, Exfoliation joint, 0104 chemical sciences, lcsh:QD1-999, chemistry, Chemical engineering, electrical properties, 0210 nano-technology
Abstract: Quasi all water soluble composites use graphene oxide (GO) or reduced graphene oxide (rGO) as graphene based additives despite the long and harsh conditions required for their preparation. Herein, polyvinyl alcohol (PVA) films containing few layer graphene (FLG) are prepared by the co-mixing of aqueous colloids and casting, where the FLG colloid is first obtained via an efficient, rapid, simple, and bio-compatible exfoliation method providing access to relatively large FLG flakes. The enhanced mechanical, electrical conductivity, and O2 barrier properties of the films are investigated and discussed together with the structure of the films. In four different series of the composites, the best Young&rsquo, s modulus is measured for the films containing around 1% of FLG. The most significant enhancement is obtained for the series with the largest FLG sheets contrary to the elongation at break which is well improved for the series with the lowest FLG sheets. Relatively high one-side electrical conductivity and low percolation threshold are achieved when compared to GO/rGO composites (almost 10&minus, 3 S/cm for 3% of FLG and transport at 0.5% FLG), while the conductivity is affected by the formation of a macroscopic branched FLG network. The composites demonstrate a reduction of O2 transmission rate up to 60%.
Published: 2020
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15. Few layer graphene as a template for Fe-based 2D nanoparticles

Author: Izabela Janowska, V. Da Costa, Anurag Mohanty, Walid Baaziz, Mama Lafjah, Institut de chimie et procédés pour l'énergie, l'environnement et la santé (ICPEES), Université de Strasbourg (UNISTRA)-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA), Centre National de la Recherche Scientifique (CNRS), Université de Strasbourg (UNISTRA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et Nanosciences Grand-Est (MNGE), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et Nanosciences Grand-Est (MNGE), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), and Janowska, Izabela
Subjects: Materials science, Carbon nanofiber, Annealing (metallurgy), Hexagonal crystal system, graphene, Nanoparticle, 02 engineering and technology, 2D nanoparticles, 010402 general chemistry, 021001 nanoscience & nanotechnology, 01 natural sciences, 0104 chemical sciences, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, Catalysis, structurization, Few layer graphene, Chemical engineering, [CHIM] Chemical Sciences, surface-to-volume ratio, Materials Chemistry, Ceramics and Composites, [CHIM]Chemical Sciences, Fe based, 0210 nano-technology
Abstract: International audience; Few layer graphene (FLG) supported structurally flat polygonal and hexagonal iron platelet NPs are prepared by two different high temperature annealing approaches, i.e., under "conventional" and µ-wave assisted heating. Both methods confirm that FLG acts as a template for 2D NPs tailoring, and flat Fe-based NPs with high surface-to-volume ratio are still well dispersed and stable at temperatures as high as several hundreds of C°despite weakened interfacial interactions between FLG and NPs. The high surface-to-volume ratio benefit of 2D NPs geometry is highlighted by mathematical estimation. The additional morphology of grown carbon nanofibers (CNFs) confirms the flat active faceted structures of NPs catalysts.
Published: 2018
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16. Engineering of highly conductive and ultra-thin nitrogen-doped graphene films by combined methods of microwave irradiation, ultrasonic spraying and thermal annealing

Author: Dusan Losic, Izabela Janowska, Diana N. H. Tran, Rifat Silva, Faisal Alotaibi, J. Nine, and Tran Thanh Tung
Subjects: Materials science, Annealing (metallurgy), General Chemical Engineering, Oxide, 02 engineering and technology, Thermal treatment, engineering.material, 010402 general chemistry, 01 natural sciences, Industrial and Manufacturing Engineering, law.invention, chemistry.chemical_compound, Coating, law, Environmental Chemistry, Pyrolytic carbon, Thin film, Sheet resistance, Graphene, General Chemistry, 021001 nanoscience & nanotechnology, 0104 chemical sciences, Chemical engineering, chemistry, engineering, 0210 nano-technology
Abstract: We report a new method for the fabrication of highly conductive and transparent ultrathin nitrogen (N) doped graphene films from graphene inks by combining a microwave treatment, ultrasonic nebulizer coating and thermal annealing. The starting graphene oxide (GO) solution was mixed with poly(ionic liquids) (PIL) and treated with microwave (Mw) irradiation to prepare Mw-rGO@PIL inks, which is a gentle reduction of PIL-attached reduced graphene oxide (rGO). In this non-contacting heating method, the PIL was used to not only mediate microwave irradiation and prevent disorder of the graphitic structure, but also repair the lattice defects and introduce nitrogen into the graphitic structure. The ultra-thin graphene films were prepared using the nebulizer for controlling the aerosol droplet distribution of the Mw-rGO@PIL inks coated onto quartz or glass substrates. The prepared films displayed a surface resistance of ∼1.45 × 107 Ω/sq at a transparency of ∼87%. A further thermal treatment was conducted to improve the conductivity of the prepared films by annealing at a high temperature (900 °C), which allowed complete reduction of oxygen containing groups, enhanced graphitization, and reordering of the basal graphene plane and N-doping of the carbon lattice (pyrolytic PIL). The resulting thin films significantly reduced the surface resistance in the range of 1.5 × 103 to 6.2 × 103 Ω/sq at a transparency ranging from 68 to 82%, respectively. The presented method involving in situ N-doping offers a promising environmentally-friendly, low-cost and scalable manufacture of high-quality conductive N-doped graphene films.
Published: 2018
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17. Great enhancement of mechanical features in <scp>PLA</scp> based composites containing aligned few layer graphene ( <scp>FLG</scp> ), the effect of <scp>FLG</scp> loading, size, and dispersion on mechanical and thermal properties

Author: Benoit Van der Schueren, Izabela Janowska, Anaëlle Bolley, Samuel Dagorne, Damien Favier, Hamza El Marouazi, and Thierry Dintzer
Subjects: Materials science, Polymers and Plastics, 02 engineering and technology, General Chemistry, 010402 general chemistry, 021001 nanoscience & nanotechnology, 01 natural sciences, 0104 chemical sciences, Surfaces, Coatings and Films, Few layer graphene, Dispersion (optics), Thermal, Materials Chemistry, Composite material, 0210 nano-technology
Published: 2021
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18. Tartrazine removal from water using functionalized multiwall carbon nanotubes

Author: D. Begin, O. Guellati, Izabela Janowska, Ncholu I. Manyala, M. Guerioune, A. Benjaballah, and A. Nait-Merzoug
Subjects: chemistry.chemical_element, 02 engineering and technology, Carbon nanotube, 010402 general chemistry, 021001 nanoscience & nanotechnology, 01 natural sciences, 0104 chemical sciences, Nanomaterials, law.invention, chemistry.chemical_compound, Adsorption, chemistry, Chemical engineering, law, Specific surface area, medicine, Water treatment, 0210 nano-technology, Carbon, Tartrazine, Activated carbon, medicine.drug
Published: 2017
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19. Tuning the structure of in-situ synthesized few layer graphene/carbon composites into nanoporous vertically aligned graphene electrodes with high volumetric capacitance

Author: Izabela Janowska, Anurag Mohanty, Janowska, Izabela, Institut de chimie et procédés pour l'énergie, l'environnement et la santé (ICPEES), Université de Strasbourg (UNISTRA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et Nanosciences Grand-Est (MNGE), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Université de Strasbourg (UNISTRA)-Matériaux et nanosciences d'Alsace (FMNGE), and Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Materials science, [SPI] Engineering Sciences [physics], General Chemical Engineering, graphene edges, FOS: Physical sciences, chemistry.chemical_element, Applied Physics (physics.app-ph), 02 engineering and technology, [SPI.MAT] Engineering Sciences [physics]/Materials, 010402 general chemistry, 01 natural sciences, Capacitance, Pseudocapacitance, volumetric capacitance, [PHYS] Physics [physics], [SPI.MAT]Engineering Sciences [physics]/Materials, [SPI]Engineering Sciences [physics], [CHIM] Chemical Sciences, Electrochemistry, [CHIM]Chemical Sciences, Graphite, [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat], [PHYS]Physics [physics], Condensed Matter - Materials Science, [CHIM.MATE] Chemical Sciences/Material chemistry, Carbonization, Nanoporous, Materials Science (cond-mat.mtrl-sci), Physics - Applied Physics, [CHIM.MATE]Chemical Sciences/Material chemistry, 021001 nanoscience & nanotechnology, Exfoliation joint, 0104 chemical sciences, nanoporosity, chemistry, Chemical engineering, Gravimetric analysis, graphene composites, 0210 nano-technology, Carbon, [PHYS.COND] Physics [physics]/Condensed Matter [cond-mat], vertically aligned graphene, pseudocapacitance
Abstract: International audience; Few layer graphene/carbon (FLG/C) composites are prepared directly via the rapid and simple exfoliation of expanded graphite in the presence of carbon based natural precursors (i.e. protein, polysaccharide) in water, followed by carbonization process. Several parameters such as nature of C-precursor, FLG/C ratio and carbonization conditions (gas, temperature) are modified in order to optimize the morphology, composition and porosity of FLG/C and thereby investigate their impact on gravimetric and volumetric capacitance, their stability and contribution of pseudocapacitance (Ps) vs. Double-layer capacitance (DL). Few composites exhibit extremely high capacitance considering their low BET-surface area ranging in 130e260 m 2 /g. The highest gravimetric and volumetric capacitance of 322 F/g and 467 F/cm 3 respectively (0.5 A/g); and energy/power performance is reached for FLG/C:1/2, synthesized from graphite-bovine serum albumin (BSA). Despite relatively high theoretical pseudocapacitance contribution of 69% (1.1 V), this sample shows also high capacity retention at high current density and elevated energy-to-power densities. The overall great capacity performance is attributed to the high electrochemical surface area from combined structural features: ultramicroporosity, FLG alignment with high accessibility of FLG edges and elevated packing density. The transport limitation enhances however at higher scan rate (>100 mV/s).
Published: 2019
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20. Macronization/densification of graphenes via vibratory compaction

Author: T. Dintzer, Azhar A. Pirzado, Izabela Janowska, Institut de chimie et procédés pour l'énergie, l'environnement et la santé (ICPEES), Université de Strasbourg (UNISTRA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et Nanosciences Grand-Est (MNGE), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), and Janowska, Izabela
Subjects: [CHIM.MATE] Chemical Sciences/Material chemistry, Materials science, Graphene, General Chemical Engineering, graphene, Compaction, toxicity, Nanotechnology, [CHIM.MATE]Chemical Sciences/Material chemistry, 02 engineering and technology, 010402 general chemistry, 021001 nanoscience & nanotechnology, 01 natural sciences, sieves separation, [SPI.MECA.GEME]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Mechanical engineering [physics.class-ph], 0104 chemical sciences, law.invention, law, Nano, concrete, Composite material, vibratory compaction, [SPI.MECA.GEME] Engineering Sciences [physics]/Mechanics [physics.med-ph]/Mechanical engineering [physics.class-ph], 0210 nano-technology, Carbon nanomaterials
Abstract: International audience; We report a vibratory compaction process for a macronization (and densification) of carbon nanomaterials such as few- and multilayer graphene (FLG and MLG) in order to decrease their dust forming and consequently their cyto- and ecotoxicity. Preliminary tests show that variable macro-shapes of FLG/MLG compacts (plates, spheres) are formed depending on the initial morphology of their (nano)microscopic counterparts. Such compactions of nanocarbons give more insight the potential use of graphenes for example in compaction technology of building materials (concrete). Since the vibratory compaction is performed in μms sieves system, the separation of variable size graphenes is an additional advantage
Published: 2016
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21. Tribological and mechanical investigation of acrylic-based nanocomposite coatings reinforced with PMMA-grafted-MWCNT

Author: Christian Gauthier, Ammar Al-kawaz, Cuong Pham-Huu, Izabela Janowska, A. Rubin, N. Badi, C. Blanck, and L. Jacomine
Subjects: Materials science, macromolecular substances, 02 engineering and technology, Carbon nanotube, 010402 general chemistry, 01 natural sciences, Nanomaterials, law.invention, chemistry.chemical_compound, law, General Materials Science, Composite material, Methyl methacrylate, chemistry.chemical_classification, Nanocomposite, Atom-transfer radical-polymerization, technology, industry, and agriculture, Polymer, equipment and supplies, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 0104 chemical sciences, body regions, chemistry, Polymerization, Volume fraction, 0210 nano-technology
Abstract: The chemical functionalization of carbon nanotubes (CNTs) could improve their chemical compatibility. Poly(methyl methacrylate) (PMMA)-functionalized multi-walled carbon nanotubes (MWCNTs) are prepared by in situ atom transfer radical polymerization (ATRP) using a “grafting from” approach. It allows the control of the thickness of the polymer layer grafted on MWCNTs from two parameters: the feed ratio of MMA to MWCNT, the volume fraction of solvent to MMA. This work compared the effect of several PMMA-grafted-MWNCT fillers embedded into a PMMA matrix, PMMA-grafted-MWCNT/PMMA, and obtained by solution mixing technique. We studied the tribological performances of 20 μm coatings of these nanocomposites deposited on neat PMMA. The percentage of embedded fillers is kept low to maintain the transparency of the PMMA. The coefficient of friction was found to relatively decrease with the increase of the weight fraction of polymer grafted to the surface of MWCNT. Moreover the elastic modulus also increased with increasing the weight fraction of PMMA coated MWCNT.
Published: 2016
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22. CNTs’ array growth using the floating catalyst-CVD method over different substrates and varying hydrogen supply

Author: M. Guerioune, Simona Moldovan, D. Begin, F. Antoni, Cuong Pham-Huu, O. Guellati, Izabela Janowska, Laboratoire de Physique des Rayonnements, Université Badji Mokhtar, 23000 Annaba, Algeria (Université Badji Mokhtar), Université Badji Mokhtar - Laboratoire de Physique des Rayonnements, University of Souk Ahras [Algeria], Institut de chimie et procédés pour l'énergie, l'environnement et la santé (ICPEES), Université de Strasbourg (UNISTRA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et Nanosciences Grand-Est (MNGE), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et Nanosciences Grand-Est (MNGE), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), Laboratoire des sciences de l'ingénieur, de l'informatique et de l'imagerie (ICube), École Nationale du Génie de l'Eau et de l'Environnement de Strasbourg (ENGEES)-Université de Strasbourg (UNISTRA)-Institut National des Sciences Appliquées - Strasbourg (INSA Strasbourg), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National de Recherche en Informatique et en Automatique (Inria)-Les Hôpitaux Universitaires de Strasbourg (HUS)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et Nanosciences Grand-Est (MNGE), Université de Strasbourg (UNISTRA)-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA), Institut National des Sciences Appliquées - Strasbourg (INSA Strasbourg), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-École Nationale du Génie de l'Eau et de l'Environnement de Strasbourg (ENGEES)-Réseau nanophotonique et optique, Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Matériaux et nanosciences d'Alsace (FMNGE), and Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Materials science, Corundum, 02 engineering and technology, Substrate (electronics), Carbon nanotube, Chemical vapor deposition, engineering.material, 010402 general chemistry, 01 natural sciences, law.invention, Crystallinity, law, [CHIM]Chemical Sciences, General Materials Science, ComputingMilieux_MISCELLANEOUS, Mechanical Engineering, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 0104 chemical sciences, Amorphous solid, Surface coating, Chemical engineering, Mechanics of Materials, engineering, Sapphire, 0210 nano-technology
Abstract: In the present investigation, we point out the effect of the substrate crystallinity on the growth rate, efficiency, quality and the structure of synthesized aligned carbon nanotubes (CNTs). Three substrates are tested: amorphous alumina (Al2O3), silica (Si/SiO2), and crystalline alumina (sapphire). The growth is carried out using the floating catalyst-CVD process with the ferrocene-toluene solution as precursor. In addition, different concentrations of H2 in the gas supply are investigated. It is observed that the sapphire substrate provides a more homogenous forest of vertically oriented straight nanotubes with small diameter, despite initial horizontal alignment of the nanotubes. In the presence of H2, long arrays of high L/Φ aspect ratio nanotubes were obtained with a reduction of diameter and the number of walls. L/Φ aspect ratio in the case of 7% H2 is c.a. 3600 for sapphire substrate, 1500 and 2000 for alumina and silica amorphous substrate, respectively. When sapphire substrate is used, the increase of H2 to 15% provides the L/Φ aspect ratio of ∼14,000.
Published: 2018
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23. The impact of synthesis method of CNT supported CeZrO2 and Ni-CeZrO2 on catalytic activity in WGS reaction

Author: Thierry Dintzer, Barbara Liszka, Mama Lafjah, Krzysztof Matus, Joaquín Silvestre-Albero, Agata Łamacz, Izabela Janowska, Universidad de Alicante. Departamento de Química Inorgánica, Universidad de Alicante. Instituto Universitario de Materiales, and Materiales Avanzados
Subjects: Thermogravimetric analysis, Química Inorgánica, Materials science, CNTs, Ceria-zirconia, Non-blocking I/O, Nanotechnology, 02 engineering and technology, General Chemistry, 010402 general chemistry, 021001 nanoscience & nanotechnology, 01 natural sciences, Catalysis, Water-gas shift reaction, 0104 chemical sciences, Adsorption, Chemical engineering, X-ray photoelectron spectroscopy, Nickel, Mixed oxide, Temperature-programmed reduction, 0210 nano-technology, WGS
Abstract: Carbon nanotube (CNT) supported catalysts containing ceria-zirconia mixed oxide (CeZrO2) and nickel were synthesized and tested in water gas shift (WGS) reaction. Physicochemical characterization including N2 adsorption, X-ray diffraction (XRD), scanning and transmission microscopy (SEM/TEM), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA) and temperature programmed reduction with H2 (H2-TPR), as well as catalytic tests of WGS reaction showed that the synthesis method had significant impact on composition, morphology, structural properties and catalytic performance of obtained hybrid materials. The catalysts obtained by co-precipitation of metal oxides (NiO and/or CeZrO2) on CNT walls demonstrated better dispersion of active phase and smaller particle size than catalyst obtained by depositing of powder CeZrO2 or Ni-CeZrO2. Moreover, the catalyst obtained by co-precipitation revealed better performance in WGS reaction; however, some CH4 formation was noticed over Ni-CeZrO2/CNT system. The role of CeZrO2 in catalysts performance in WGS as well as the importance of good metal-oxide contact were confirmed. The work was financed by a statutory activity subsidy from the Polish Ministry of Science and Higher Education for the Faculty of Chemistry of Wrocław University of Technology. A.Ł. would like to acknowledge: the French Embassy in Poland for financing scientific stay in ICPEES in the frame of SSHN-2014 program, the Polish Ministry of Science and Higher Education for financing studies on WGS reaction (Iuventus Plus, IP2011030871) and the National Science Centre for financing studies on H2O dissociation (UMO 2011/03/N/ST5/04658).
Published: 2018

24. Influence of the reaction temperature on the oxygen reduction reaction on nitrogen-doped carbon nanotube catalysts

Author: Antoine Bonnefont, Won Hui Doh, Elena R. Savinova, Pascal Granger, Dominique Begin, Lai Truong-Phuoc, Cuong Duong-Viet, Cuong Pham-Huu, and Izabela Janowska
Subjects: Chemistry, Industrial catalysts, Inorganic chemistry, General Chemistry, Carbon nanotube, Activation energy, Electrolyte, Overpotential, Electrocatalyst, Catalysis, law.invention, law, Carbon nanotube supported catalyst
Abstract: Nitrogen-doped carbon nanotubes (N-CNT) were synthesized at 700 °C via the chemical vapour deposition (CVD) method and were used as catalysts in the oxygen reduction reaction (ORR) in 0.1 M KOH. The activity toward the ORR and the stability of these N-CNTs in alkaline solution were studied as a function of the reaction temperature and of the chemical treatment applied to the catalyst. The kinetic analysis of these catalysts was also carried out and compared to the ORR performance of the commercial Pt/C Vulcan XC72 catalyst. N-CNT-700BW catalyst without any chemical treatment after the CVD synthesis, possesses a half-wave potential E1/2 of approximately 0.82 V vs. RHE, 50 mV lower than the E1/2 value of Pt/C catalyst and a specific current density Jk at 0.9 V = 5.46 mA/mg at T = 25 °C. Removal of the major part of the iron growth catalyst by a chemical treatment resulted in a strongly decreased but still measurable activity. The activation energy of the N-CNT-based catalyst was calculated and is around 38 kJ mol−1 at an ORR overpotential of 300 mV. Increasing the temperature of the electrolyte up to 75 °C leads to a positive shift of the half-wave potential of the reaction as well as an increase of the H2O2 escape. The long-term stability test has also been conducted and indicates a good stability of the activity of the N-CNT-based catalysts under operation in alkaline media.
Published: 2015
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25. Hybrid Films of Graphene and Carbon Nanotubes for High Performance Chemical and Temperature Sensing Applications

Author: TaeYoung Kim, Izabela Janowska, Mickaël Castro, Tran Thanh Tung, Cuong Pham-Huu, and Jean-François Feller
Subjects: Materials science, Graphene, Composite number, chemistry.chemical_element, Nanotechnology, General Chemistry, Carbon nanotube, Thermoelectric materials, law.invention, Biomaterials, chemistry, law, Thermoelectric effect, General Materials Science, Hybrid material, Carbon, Graphene nanoribbons, Biotechnology
Abstract: A hybrid composite material of graphene and carbon nanotube (CNT) for high performance chemical and temperature sensors is reported. Integration of 1D and 2D carbon materials into hybrid carbon composites is achieved by coupling graphene and CNT through poly(ionic liquid) (PIL) mediated-hybridization. The resulting CNT/PIL/graphene hybrid materials are explored as active materials in chemical and temperature sensors. For chemical sensing application, the hybrid composite is integrated into a chemo-resistive sensor to detect a general class of volatile organic compounds. Compared with the graphene-only devices, the hybrid film device showed an improved performance with high sensitivity at ppm level, low detection limit, and fast signal response/recovery. To further demonstrate the potential of the hybrid films, a temperature sensor is fabricated. The CNT/PIL/graphene hybrid materials are highly responsive to small temperature gradient with fast response, high sensitivity, and stability, which may offer a new platform for the thermoelectric temperature sensors.
Published: 2015
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26. Evaporation-induced self-assembling of few-layer graphene into a fractal-like conductive macro-network with a reduction of percolation threshold

Author: Izabela Janowska, Institut de chimie et procédés pour l'énergie, l'environnement et la santé (ICPEES), Université de Strasbourg (UNISTRA)-Matériaux et nanosciences d'Alsace (FMNGE), and Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: [PHYS]Physics [physics], Chemical Physics (physics.chem-ph), Condensed Matter - Materials Science, Materials science, Graphene, Materials Science (cond-mat.mtrl-sci), FOS: Physical sciences, General Physics and Astronomy, Percolation threshold, Nanotechnology, [CHIM.MATE]Chemical Sciences/Material chemistry, Nonlinear Sciences - Adaptation and Self-Organizing Systems, law.invention, Few layer graphene, Fractal, law, Physics - Chemical Physics, Nano, Self assembling, [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat], Physical and Theoretical Chemistry, Macro, Adaptation and Self-Organizing Systems (nlin.AO), Electrical conductor
Abstract: The transcription of nanoproperties to other dimensions in an efficient and simple way by the appropriate design of devices is a challenge, and conductive nanocarbon systems are considered here. The evaporation-induced self-assembling method is proposed to form branched, fractal-like "2D" conductive macrostructures from (nano) micro few-layer graphene flakes. The self-assembled conductive graphene networks reveal a reduction of percolation threshold compared to a random arrangement (a lower matter concentration is required to make a given substrate conductive and at a lower coverage), and become a promising matrix for conductive (transparent) films. The method is easy, cost-efficient and can potentially be applied on unlimited surfaces.
Published: 2015
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27. Nitrogen-doped carbon nanotubes decorated silicon carbide as a metal-free catalyst for partial oxidation of H2S

Author: Lam Nguyen-Dinh, Lai Truong-Phuoc, Cuong Pham-Huu, Tung Tran-Thanh, Izabela Janowska, Duong-Viet Cuong, Jean-Mario Nhut, and Dominique Begin
Subjects: Process Chemistry and Technology, Catalyst support, chemistry.chemical_element, Nanotechnology, Carbon nanotube, Catalysis, law.invention, chemistry.chemical_compound, chemistry, Chemical engineering, law, Silicon carbide, Carbon nanotube supported catalyst, Partial oxidation, Carbon, Space velocity
Abstract: Hierarchical metal-free catalyst based on the CVD synthesis of nitrogen-doped carbon nanotubes decorated silicon carbide (N-CNTs/SiC) macroscopic host structure has been prepared. The catalyst was evaluated in the partial oxidation of H 2 S by oxygen into elemental sulfur in a fixed-bed reactor. The catalytic results indicate that the N-CNTs/SiC catalyst exhibits an extremely high desulfurization performance even under severe reaction conditions such as low temperature, high space velocity and at low O 2 -to-H 2 S molar ratio. The high desulfurization performance was attributed to the high effective surface area of the catalyst along with a short diffusion length associated with the nanoscopic dimension of the carbon nanotubes. The N-CNTs/SiC catalyst also displays a high stability as a function of time on stream which could be attributed to the strong anchoring of the nitrogen doping within the carbon matrix. The extrudates shape of the SiC support allows the direct macroscopic shaping of the catalyst for use in conventional fixed-bed reactor without facing problems linked with catalyst handling, transportation and pressure drop across the catalyst bed as encountered with nanoscopic carbon-based catalyst.
Published: 2014
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28. A few-layer graphene–graphene oxide composite containing nanodiamonds as metal-free catalysts

Author: Izabela Janowska, Tung Tran Thanh, Dinh Lam Nguyen, Ovidiu Ersen, Dominique Begin, Housseinou Ba, Pascal Granger, Cuong Pham-Huu, Jean-Mario Nhut, and Lai Truong-Phuoc
Subjects: Materials science, Renewable Energy, Sustainability and the Environment, Graphene, Oxide, General Chemistry, Ethylbenzene, Exfoliation joint, Styrene, law.invention, chemistry.chemical_compound, chemistry, Chemical engineering, law, Organic chemistry, General Materials Science, Dehydrogenation, Graphite, Hybrid material
Abstract: We report a high yield exfoliation of few-layer-graphene (FLG) with up to 17% yield from expanded graphite, under 5 h sonication time in water, using graphene oxide (GO) as a surfactant. The aqueous dispersion of GO attached FLG (FLG–GO), with less than 5 layers, is used as a template for further decoration of nanodiamonds (NDs). The hybrid materials were self-organized into 3D-laminated nanostructures, where spherical NDs with a diameter of 4–8 nm are homogeneously distributed on the surface of the FLG–GO complex (referred to as FLG–GO@NDs). It was found that GO plays a dual role, it (1) mediated exfoliation of expanded graphite in aqueous solution resulting in a FLG–GO colloid system, and (2) incorporated ND particles for the formation of composites. A high catalytic performance in the dehydrogenation of ethyl-benzene on FLG–GO@ND metal-free catalyst is achieved; 35.1% of ethylbenzene conversion and 98.6% styrene selectivity after a 50 h reaction test are observed which correspond to an activity of 896 mmolST gcatalyst−1 h−1, which is 1.7 and 5 times higher than those of the unsupported NDs and traditional catalysts, respectively. The results demonstrate the potential of the FLG–GO@ND composite as a promising catalyst for steam-free industrial dehydrogenation applications.
Published: 2014
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29. Magnetic Properties of Poly(trimethylene terephthalate‐ block ‐Poly(tetramethylene oxide) Copolymer Nanocomposites Reinforced by Graphene Oxide–Fe 3 O 4 Hybrid Nanoparticles

Author: Zdenko Špitalský, N. Guskos, Anna Szymczyk, Izabela Janowska, Grzegorz Żołnierkiewicz, Janusz Typek, and Sandra Paszkiewicz
Subjects: 010302 applied physics, Thermogravimetric analysis, Nanocomposite, Materials science, Graphene, Nanoparticle, 02 engineering and technology, Surfaces and Interfaces, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 01 natural sciences, Ferromagnetic resonance, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, law.invention, Differential scanning calorimetry, Chemical engineering, law, 0103 physical sciences, Materials Chemistry, Electrical and Electronic Engineering, In situ polymerization, 0210 nano-technology, Superparamagnetism
Abstract: Thermoplastic elastomeric nanocomposites based on poly(trimethylene terephthalate-block-poly(tetramethylene oxide) copolymer (PTT-PTMO) and graphene oxide-Fe3O4 nanoparticle hybrid were prepared by in situ polymerization. Superparamagnetic GO-Fe3O4 hybrid nanoparticles before introducing to elastomeric matrix were characterized by X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), thermogravimetric analysis (TGA) and scanning electron microscopy (SEM). The effect of loading (0.3 and 0.5 wt%) of GO-Fe3O4 nanoparticle hybrid on the phase structure, tensile and magnetic properties of synthesized nanocomposites was investigated. The phase structure of nanocomposites was evaluated by differential scanning calorimetry (DSC) and dynamic mechanical thermal analysis (DMTA). Dispersion of GO-Fe3O4 nanoparticles in elastomeric matrix was evaluated by transmission electron microscopy (TEM). Magnetic properties of GO-Fe3O4 nanoparticle hybrid and nanocomposites with their content were characterized by using two different techniques: dc SQUID magnetization measurements as a function of temperature (from 2 to 300 K) and external magnetic field and ferromagnetic resonance (FMR) at microwave frequency.
Published: 2019
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30. Effect of the Specific Surface Sites on the Reducibility of α-Fe2O3/Graphene Composites by Hydrogen

Author: Raoul Blume, Vasiliki Papaefthimiou, Dominique Begin, Walid Baaziz, D. Begin, Izabela Janowska, Ovidiu Ersen, Won Hui Doh, Ileana Florea, Axel Knop-Gericke, Cuong Pham-Huu, and Spyridon Zafeiratos
Subjects: Materials science, Hydrogen, Inorganic chemistry, Iron oxide, chemistry.chemical_element, 02 engineering and technology, 010402 general chemistry, 01 natural sciences, law.invention, chemistry.chemical_compound, X-ray photoelectron spectroscopy, law, Physical and Theoretical Chemistry, Graphene oxide paper, X-ray absorption spectroscopy, Graphene, Electron energy loss spectroscopy, technology, industry, and agriculture, 021001 nanoscience & nanotechnology, 0104 chemical sciences, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, General Energy, chemistry, 0210 nano-technology, Iron oxide nanoparticles
Abstract: The reducibility of iron oxide nanoparticles (NPs) supported over few-layer thick graphite upon annealing in hydrogen is investigated by near ambient pressure X-ray photoelectron spectroscopy (NAP-XPS), X-ray absorption spectroscopy (XAS), electron energy loss spectroscopy (EELS), and high-resolution transmission electron microscopy (HR-TEM). It is found that the stability of the iron oxide NPs toward reduction is enhanced by the interaction with the graphene nanosheets as compared to the bulk iron oxide. Postannealing TEM micrographs reveal the existence of both core/shell and homogeneous iron oxide NPs with the latter forming irregular trenches into the graphene sheets. EELS analysis and TEM images clearly demonstrate that the reducibility of iron oxide particles depends on the specific graphene site on which they are attached. Furthermore, we show that graphene etching can be mediated by iron oxide NPs at relatively mild reduction conditions.
Published: 2013
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31. Examining the impact of multi-layer graphene using cellular and amphibian models

Author: Laura Muzi, Izabela Janowska, Stéphanie Cadarsi, Alberto Bianco, Eric Pinelli, Laury Gauthier, Brigitte Soula, Cécilia Ménard-Moyon, Gianfranco Risuleo, Florence Mouchet, Anne Marie Galibert, Julie Russier, Emmanuel Flahaut, Immunopathologie et chimie thérapeutique (ICT), Centre National de la Recherche Scientifique (CNRS)-Institut de biologie moléculaire et cellulaire (IBMC), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome], Laboratoire Ecologie Fonctionnelle et Environnement (ECOLAB), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Institut de chimie et procédés pour l'énergie, l'environnement et la santé (ICPEES), Université de Strasbourg (UNISTRA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Centre interuniversitaire de recherche et d'ingenierie des matériaux (CIRIMAT), Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC), Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - INPT (FRANCE), Università di Roma - SAPIENZA (ITALY), Université de Strasbourg - UNISTRA (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Laboratoire Ecologie fonctionnelle et Environnement - EcoLab (Toulouse, France), Institut de biologie moléculaire et cellulaire (IBMC), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome] (UNIROMA), Laboratoire Ecologie Fonctionnelle et Environnement (LEFE), Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT), Université de Strasbourg (UNISTRA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et Nanosciences Grand-Est (MNGE), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), and Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE)
Subjects: Materials science, Inflammatory response, Biochimie, Cytotoxicity, Context (language use), Nanotechnology, 02 engineering and technology, 010501 environmental sciences, Ecotoxicologie, 01 natural sciences, law.invention, [CHIM.GENI]Chemical Sciences/Chemical engineering, law, Mammalian cell, Few-layer graphene, Génie chimique, General Materials Science, Mortality, [SDV.BBM.BC]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Biochemistry [q-bio.BM], Multi layer, Organism, 0105 earth and related environmental sciences, Environmental model, Graphene, Mechanical Engineering, Macrophages, Xenopus larvae, General Chemistry, Photothermal therapy, 021001 nanoscience & nanotechnology, Condensed Matter Physics, Microbiologie et Parasitologie, [SDV.MP]Life Sciences [q-bio]/Microbiology and Parasitology, Mechanics of Materials, [SDV.TOX.ECO]Life Sciences [q-bio]/Toxicology/Ecotoxicology, Genotoxicity, 0210 nano-technology
Abstract: International audience; In the last few years, graphene has been defined as the revolutionary material showing an incredible expansion in industrial applications. Different graphene forms have been applied in several contexts, spreading from energy technologies and electronics to food and agriculture technologies. Graphene showed promises also in the biomedical field. Hopeful results have been already obtained in diagnostic, drug delivery, tissue regeneration and photothermal cancer ablation. In view of the enormous development of graphene-based technologies, a careful assessment of its impact on health and environment is demanded. It is evident how investigating the graphene toxicity is of fundamental importance in the context of medical purposes. Onthe other hand, the nanomaterial present in the environment, likely to be generated all along the industrial life-cycle, may have harmful effects on living organisms. In the present work, an important contribution on the impact of multi-layer graphene (MLG) on health and environment is given by using a multifaceted approach. For the first purpose, the effect of the material on two mammalian cell models was assessed. Key cytotoxicity parameters were considered such as cell viability and inflammatory response induction. This was combined with an evaluation ofMLGtoxicity towards Xenopus laevis, used as both in vivo and environmental model organism.
Published: 2016
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32. Mechanical thinning to make few-layer graphene from pencil lead

Author: Cuong Pham-Huu, Ovidiu Ersen, Pierre Bernhardt, Marc-Jacques Ledoux, Fabrice Vigneron, Dominique Begin, Thierry Romero, and Izabela Janowska
Subjects: Materials science, Scanning electron microscope, Graphene, Sonication, Nanotechnology, General Chemistry, Pencil (optics), law.invention, Micrometre, symbols.namesake, Few layer graphene, Transmission electron microscopy, law, symbols, General Materials Science, Composite material, Raman spectroscopy
Abstract: Simple, fast and low cost production of graphene and few-layer graphene (FLG) with high yield is presented. The synthesis consists of mechanical ablation of pencil lead on a harsh glass surface with simultaneous ultrasonication followed by a purification to remove the inorganic binder present in the pencil lead. The combination of several characterization techniques, i.e. SEM, TEM and Raman show that FLG with lateral size of few micrometers, consisted of 1 up to 20 and occasionally up to fifty sheets is obtained by this process.
Published: 2012
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33. Macroscopic shaping of carbon nanotubes with high specific surface area and full accessibility

Author: Yuefeng Liu, Dominique Begin, Lam D. Nguyen, Cuong Pham-Huu, Izabela Janowska, Thierry Romero, Tri Truong-Huu, and Yu Liu
Subjects: Packed bed, Pressure drop, Materials science, Mechanical Engineering, Catalyst support, Carbon nanotube, Condensed Matter Physics, Catalysis, law.invention, Mechanics of Materials, law, Specific surface area, General Materials Science, Composite material, Porosity, Nanoscopic scale
Abstract: Carbon nanotubes (CNTs) with controlled macroscopic shape, i.e. beads, extrudates, disk, etc., were prepared by gelation process. The formed CNT beads (1-2 mm) were constituted by highly entangled CNT forming a dense network exhibiting a rather high specific surface (> 180 m 2 .g − 1 ) and also full porous network accessibility. The highly opened porosity of this material also drastically reduces the overall pressure drop across the packed bed compared to the bulk CNT material. The macroscopic shaping eases the handling and the transport of these nanoscopic materials and permits the direct use of them as catalyst supports in conventional catalytic processes.
Published: 2012
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34. 3D Analysis of the Morphology and Spatial Distribution of Nitrogen in Nitrogen-Doped Carbon Nanotubes by Energy-Filtered Transmission Electron Microscopy Tomography

Author: Ovidiu Ersen, Dris Ihiawakrim, Cédric Messaoudi, Kambiz Chizari, Raul Arenal, Ileana Florea, Izabela Janowska, and Cuong Pham-Huu
Subjects: Analytical chemistry, chemistry.chemical_element, General Chemistry, Iterative reconstruction, Carbon nanotube, Biochemistry, Nitrogen, Catalysis, law.invention, Condensed Matter::Materials Science, Colloid and Surface Chemistry, chemistry, Transmission electron microscopy, law, Ionization, Energy filtered transmission electron microscopy, Tomography, Carbon
Abstract: We present here the application of the energy-filtered transmission electron microscopy (EFTEM) in the tomographic mode to determine the precise 3D distribution of nitrogen within nitrogen-doped carbon nanotubes (N-CNTs). Several tilt series of energy-filtered images were acquired on the K ionization edges of carbon and nitrogen on a multiwalled N-CNT containing a high amount of nitrogen. Two tilt series of carbon and nitrogen 2D maps were then calculated from the corresponding energy-filtered images by using a proper extraction procedure of the chemical signals. Applying iterative reconstruction algorithms provided two spatially correlated C and N elemental-selective volumes, which were then simultaneously analyzed with the shape-sensitive reconstruction deduced from Zero-Loss recordings. With respect to the previous findings, crucial information obtained by analyzing the 3D chemical maps was that, among the two different kind of arches formed in these nanotubes (transversal or rounded ones depending on their morphology), the transversal arches contain more nitrogen than do the round ones. In addition, a detailed analysis of the shape-sensitive volume allowed the observation of an unexpected change in morphology along the tube axis: close to the round arches (with less N), the tube is roughly cylindrical, whereas near the transversal ones (with more N), its shape changes to a prism. This relatively new technique is very powerful in the material science because it combines the ability of the classical electron tomography to solve 3D structures and the chemical selectivity of the EFTEM imaging.
Published: 2012
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35. On the Evolution of Pt Nanoparticles on Few-Layer Graphene Supports in the High-Temperature Range

Author: Cuong Pham-Huu, Izabela Janowska, Hervé Bulou, Dominique Begin, Ovidiu Ersen, Yannick J. Dappe, M. Simona Moldovan, Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg (UNISTRA)-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA), Groupe Modélisation et Théorie (GMT), Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Service de physique de l'état condensé (SPEC - UMR3680), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut de chimie et procédés pour l'énergie, l'environnement et la santé (ICPEES), Université de Strasbourg (UNISTRA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et Nanosciences Grand-Est (MNGE), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), Service de physique de l'état condensé (SPEC - UMR3680), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Université de Strasbourg (UNISTRA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et Nanosciences Grand-Est (MNGE), and Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Materials science, Annealing (metallurgy), Nanoparticle, Sintering, Nanotechnology, 02 engineering and technology, 010402 general chemistry, 01 natural sciences, law.invention, law, Physical and Theoretical Chemistry, [PHYS]Physics [physics], Graphene, [CHIM.MATE]Chemical Sciences/Material chemistry, [CHIM.CATA]Chemical Sciences/Catalysis, Atmospheric temperature range, 021001 nanoscience & nanotechnology, 0104 chemical sciences, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, Faceting, General Energy, Chemical engineering, Electron tomography, Particle-size distribution, 0210 nano-technology
Abstract: International audience; Controlling the size, dispersion, and shape of nanoparticles (NPs) in the high-temperature range is a key topic for the development of new technologies with applications in the particular fields of catalysis and energy storage. In this article, we present an approach combining in situ transmission electron microscopy (TEM), electron tomography (ET), and molecular dynamics (MD) calculations for assessing the evolution of Pt NPs deposited onto few-layer graphene supports. Spherical Pt NPs with average sizes of 2 nm located preferentially at the support topographical defects (e.g., steps and edges) diffuse and coalesce along these defects, such that, after annealing to 700 °C, the nanoparticles were located exclusively here. Their dispersion remained significant; only the particle size distribution changed from mono- to bimodal. This statistical variation is discussed herein by reviewing fundamental issues such as the NP–support interaction and NP faceting, diffusion, and subsequent sintering in the high-temperature range. Fundamental MD simulations are reported here as reinforcements of the experimental findings and as a means to provide deeper insight into the phenomenological issues behind the behavior of the system investigated.
Published: 2012
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36. A new recyclable Pd catalyst supported on vertically aligned carbon nanotubes for microwaves-assisted Heck reactions

Author: Cuong Pham-Huu, Marc J. Ledoux, Kambiz Chizari, Jean Hubert Olivier, Raymond Ziessel, and Izabela Janowska
Subjects: Materials science, General Chemical Engineering, chemistry.chemical_element, Nanotechnology, General Chemistry, Carbon nanotube, Heterogeneous catalysis, Coupling reaction, law.invention, Catalysis, chemistry.chemical_compound, chemistry, Chemical engineering, law, Heck reaction, Ethyl acrylate, Carbon nanotube supported catalyst, Palladium
Abstract: Palladium supported on vertically aligned multi-walled carbon nanotubes (Pd/VA-CNTs) is used as catalyst for the C-C coupling reactions of p-iodonitrobenzene with styrene and ethyl acrylate under microwaves irradiation. Pd/VA-CNTs catalyst exhibits higher activity compared to Pd supported on activated charcoal, under the same reaction conditions. Due to the microwaves irradiation, the kinetics of the reaction is strongly accelerated compared to that obtained with a traditional heating mode. The macroscopic form of aligned CNTs support allows an easy recovery of the catalyst, avoiding a costly post-reaction filtration. In addition, the interaction between the active phase and the support leads to the negligible leaching of palladium during recycling tests. The observed results indicate that Pd/CNTs is a recyclable and stable heterogeneous catalytic system.
Published: 2011
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37. Tuning of nitrogen-doped carbon nanotubes as catalyst support for liquid-phase reaction

Author: Izabela Janowska, Thierry Romero, Pierre Bernhardt, Matthieu Houllé, Marc J. Ledoux, Cuong Pham-Huu, Ovidiu Ersen, Kambiz Chizari, and Ileana Florea
Subjects: Process Chemistry and Technology, Catalyst support, Inorganic chemistry, chemistry.chemical_element, Chemical vapor deposition, Carbon nanotube, Nitrogen, Catalysis, law.invention, Ammonia, chemistry.chemical_compound, chemistry, law, Carbon nanotube supported catalyst, Palladium
Abstract: This work reports the synthesis of nitrogen-doped carbon nanotubes (N-CNTs) using a Chemical Vapor Deposition (CVD) process at temperature ranging from 600 °C to 850 °C and ethane/ammonia concentration (defined as a volume percentage of C 2 H 6 /(C 2 H 6 + NH 3 )) of 20–100%. Several characterizations, i.e. XPS, SEM and TEM were done on the as-synthesized nitrogen-doped carbon nanotubes in order to get more insight about the influence of the synthesis conditions on the characteristics and properties of these N-CNTs. Depending on the synthesis conditions, the atomic percentage of nitrogen in carbon nanotubes varied from 0 at.% to about 5.5 at.%. The undoped carbon nanotubes (N-free CNTs) and two kinds of N-CNTs with different types of nitrogen incorporated species have been used as the supports for palladium in the liquid-phase hydrogenation of cinnamaldehyde. The introduction of nitrogen atoms into the carbon matrix significantly modified the chemical properties of the support compared to the N-free carbon nanotube resulting in a higher metal dispersion. N-CNTs exhibit much higher activity in the hydrogenation reaction compare to the undoped ones. Nitrogen incorporation also strongly improved the selectivity towards the C C bond hydrogenation. The results show that the type of nitrogen species incorporated in CNTs structure can also influence the catalytic activity. Recycling test confirms the high stability of the catalyst as neither palladium leaching nor deactivation has been observed.
Published: 2010
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38. High surface-to-volume hybrid platelet reactor filled with catalytically grown vertically aligned carbon nanotubes

Author: David Edouard, Nicolas Keller, Izabela Janowska, Valérie Keller, Thierry Romero, Yu Liu, Ovidiu Ersen, Lâm D. Nguyen, Cuong Pham-Huu, Beihang University (BUAA), Department of Organic Chemistry, Łódź University of Technology, Laboratoire d'automatique et de génie des procédés (LAGEP), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École Supérieure Chimie Physique Électronique de Lyon-Centre National de la Recherche Scientifique (CNRS), Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA), Laboratoire des Matériaux, Surfaces et Procédés pour la Catalyse (LMSPC), Institut de chimie et procédés pour l'énergie, l'environnement et la santé (ICPEES), Université de Strasbourg (UNISTRA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et nanosciences d'Alsace (FMNGE), and Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Materials science, Nanotechnology, 02 engineering and technology, Carbon nanotube, 010402 general chemistry, Heterogeneous catalysis, 01 natural sciences, 7. Clean energy, Catalysis, law.invention, [SPI]Engineering Sciences [physics], [CHIM.GENI]Chemical Sciences/Chemical engineering, law, [CHIM]Chemical Sciences, [SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineering, Nanoscopic scale, ComputingMilieux_MISCELLANEOUS, Pressure drop, General Chemistry, 021001 nanoscience & nanotechnology, 0104 chemical sciences, Characterization (materials science), Volume (thermodynamics), Chemical engineering, Microreactor, 0210 nano-technology
Abstract: During the last decade, microstructured reactors have received an impressive development in several fields of applications, especially in the field of catalysis where heat and mass transfers need to be improved. These reactors are generally consisting in sub-millimeter channels which exhibit an extremely high surface-to-volume ratios, typically in the range of 10,000–50,000 m2 m−3 compared to those of conventional reactors which lie between 100 and 1000 m2 m−3. In the present work we report the use of extremely high aspect ratio vertically aligned carbon nanotubes (VA-CNTs) which can be efficiently employed as a high surface-to-volume building-block for the platelet hybrid microstructured reactors. Due to the nanoscopic size of the filling material, such reactor displays an extremely high surface-to-volume ratio, expressed in terms of effective surface area along with an affordable pressure drop across the reactor. The assembly mode also allows the easy control (preparation and characterizations) and replacement of the catalyst, in case of deactivation or plugging, which is not a case for the traditional microstructured reactors.
Published: 2010
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39. Microwave synthesis of large few-layer graphene sheets in aqueous solution of ammonia

Author: D. Soubane, Marc-Jacques Ledoux, Dominique Plee, Matthieu Houllé, Ovidiu Ersen, Dominique Begin, Christine Boeglin, Virginie Speisser, Izabela Janowska, Spyridon Zafeiratos, Cuong Pham-Huu, Victor Da Costa, and Kambiz Chizari
Subjects: Materials science, Aqueous solution, Graphene, Analytical chemistry, Condensed Matter Physics, Exfoliation joint, Atomic and Molecular Physics, and Optics, law.invention, Materials Science(all), Electron diffraction, law, Transmission electron microscopy, General Materials Science, Graphite, Electrical and Electronic Engineering, Graphene nanoribbons, Graphene oxide paper
Abstract: Few-layer graphene (FLG) sheets with sizes exceeding several micrometers have been synthesized by exfoliation of expanded graphite in aqueous solution of ammonia under microwave irradiation, with an overall yield approaching 8 wt.%. Transmission electron microscopy (in bright-field and dark-field modes) together with electron diffraction patterns and atomic force microscopy confirmed that this graphene material consisted mostly of mono-, bi- or few-layer graphene (less than ten layers). The high degree of surface reduction was confirmed by X-ray photoelectron and infrared spectroscopies. In addition, the high stability of the FLG in the liquid medium facilitates the deposition of the graphene material onto several substrates via low-cost solution-phase processing techniques, opening the way to subsequent applications of the material.
Published: 2010
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40. Catalytic unzipping of carbon nanotubes to few-layer graphene sheets under microwaves irradiation

Author: Izabela Janowska, Cuong Pham-Huu, Philippe Vennéguès, Timo Jacob, Dominique Begin, Marc-Jacques Ledoux, and Ovidiu Ersen
Subjects: Nanotube, Graphene, Process Chemistry and Technology, chemistry.chemical_element, Nanoparticle, Nanotechnology, Carbon nanotube, Catalysis, Nanomaterial-based catalyst, law.invention, chemistry, Chemical engineering, law, Carbon, Graphene nanoribbons, Palladium
Abstract: Catalytic unzipping of single-, double-, and multi-walled carbon nanotubes (SWNTs, DWNTs, and MWNTs), in the presence of Pd nanoparticles and an oxygen-containing liquid medium, to yield the few-layer graphene sheets, was performed under microwaves irradiation. In this unzipping process, the palladium particles act as a pair of scissors to cut the nanotube lengthways. Theoretical simulations with Reactive Forcefields confirm that the presence of Pd nanocatalysts and oxygen next to vacancies facilitate the unzipping process to form graphene from nanotube by significantly lowering the corresponding energy barrier. This synthesis method makes a link between nanotubes and graphene sheets, yielding a significant amount of graphene (between 4 and 8 wt.% with respect to the starting carbon material). Compared to previous methods, scaling-up can easily be achieved by increasing the number of synthesis reactors, leading to gram-amounts of graphene.
Published: 2009
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41. Selective Deposition of Palladium Nanoparticles inside the Bimodal Porosity of β-SiC Investigated by Electron Tomography

Author: Charlotte Pham, Adrien Deneuve, Cuong Pham-Huu, Patrick Nguyen, Izabela Janowska, Ileana Florea, Lucian Roiban, Ovidiu Ersen, and Matthieu Houllé
Subjects: Materials science, business.industry, Nanotechnology, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, chemistry.chemical_compound, General Energy, Electron tomography, chemistry, Specific surface area, visual_art, visual_art.visual_art_medium, Silicon carbide, Microelectronics, Nanometre, Ceramic, Physical and Theoretical Chemistry, Porosity, Dispersion (chemistry), business
Abstract: Silicon carbide (SiC) is a ceramic material that has received intensive consideration during the past decade owing to its attractive properties and the diversity of its applications, ranging from microelectronics to catalysis. In particular, new β-SiC materials with high specific surface area are of great interest to the area of industrial catalysis. The aim of the present article is to report the direct visualization of the porous network of β-SiC in a nanometer range using the ability of electron tomography (ET) but also to determine the precise localization of active phases with respect to the porosity of this support. Focus is set on the use of ET to get more insight about the filling mode during sample preparation and, finally, the dispersion and accessibility of the active phase. Thus, an intensive study of the impact of the impregnation solvents on the active phase localization has also been carried out and selective deposition of the active phase within the porous network of SiC is evidenced. In a...
Published: 2009
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42. Macronized aligned carbon nanotubes for use as catalyst support and ceramic nanoporous membrane template

Author: Dominique Begin, Cuong Pham-Huu, Izabela Janowska, Marc-Jacques Ledoux, Shabnam Hajiesmaili, Valérie Keller, and Nicolas Keller
Subjects: Materials science, Catalyst support, Nanotechnology, General Chemistry, Carbon nanotube, Chemical vapor deposition, Substrate (printing), Catalysis, law.invention, Micrometre, Membrane, Chemical engineering, law, visual_art, visual_art.visual_art_medium, Ceramic
Abstract: An aligned carbon nanotube carpet was synthesized by catalytic chemical vapor deposition (CCVD) process at 800 °C with a mixture of ferrocene and toluene, using a removable quartz substrate as macroscopic pre-form. The strong anchorage of the aligned nanotube array at the macroscopic host surface allows the nano–macro-composite to be considered as a nano-ordered macroscopic material and self-supported aligned nanotubes could be obtained by substrate removal. The carpet thickness could be accurately controlled from few tenth micrometers to more than few millimeters by tuning the synthesis duration. Such a nano–macro-composite could be used as high contact surface catalyst support with low pressure drop. The aligned nanotube array was efficiently used as removable precursor template in the design of β-SiC ceramic nanoporous membranes.
Published: 2009
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43. N-doped carbon nanotubes for liquid-phase CC bond hydrogenation

Author: Matthieu Houllé, Ovidiu Ersen, Kambiz Chizari, Izabela Janowska, Cuong Pham-Huu, Dominique Begin, and Julien Amadou
Subjects: Materials science, Carbon nanofiber, Graphene, Inorganic chemistry, Selective chemistry of single-walled nanotubes, chemistry.chemical_element, General Chemistry, Carbon nanotube, Catalysis, law.invention, Carbon nanobud, chemistry, law, Carbide-derived carbon, Carbon nanotube supported catalyst, Carbon
Abstract: The introduction of foreign elements inside the channel of carbon nanotubes could lead to a significant modification of the intrinsic properties of these nanomaterials. Nitrogen atoms entering in the graphene sheets as substitute of carbon could modify in a large extend the acido-basic properties and also adsorption of the nanotube itself. Depending on the synthesis conditions, i.e. nature of the N-source, temperature and C-to-N atomic ratio, various N-doped carbon nanotubes can be synthesized with different surface properties. The aim of the present work is to report the synthesis of N-doped CNTs using a common nitrogen source precursor namely ammonia (NH 3 ) with C 2 H 6 as carbon source. The as-synthesized N-CNTs were subsequently employed as catalyst support in the liquid-phase hydrogenation of cinnamaldehyde using palladium as an active phase.
Published: 2008
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44. Activation of few layer graphene by μW-assisted oxidation in water via formation of nanoballs – Support for platinum nanoparticles

Author: Tran Thanh-Tung, Izabela Janowska, Vasiliki Papaefthimiou, François Le Normand, Cuong Pham-Huu, Lai Truong-Phuoc, Azhar A. Pirzado, Camelia Matei Ghimbeu, Housseinou Ba, Institut de chimie et procédés pour l'énergie, l'environnement et la santé (ICPEES), Université de Strasbourg (UNISTRA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Laboratoire des sciences de l'ingénieur, de l'informatique et de l'imagerie (ICube), Institut National des Sciences Appliquées - Strasbourg (INSA Strasbourg), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-École Nationale du Génie de l'Eau et de l'Environnement de Strasbourg (ENGEES)-Réseau nanophotonique et optique, Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Institut de Science des Matériaux de Mulhouse (IS2M), Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA), Université de Strasbourg (UNISTRA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et Nanosciences Grand-Est (MNGE), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), École Nationale du Génie de l'Eau et de l'Environnement de Strasbourg (ENGEES)-Université de Strasbourg (UNISTRA)-Institut National des Sciences Appliquées - Strasbourg (INSA Strasbourg), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National de Recherche en Informatique et en Automatique (Inria)-Les Hôpitaux Universitaires de Strasbourg (HUS)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et Nanosciences Grand-Est (MNGE), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et Nanosciences Grand-Est (MNGE), and Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique
Subjects: Materials science, Nanoparticle, Nanotechnology, 02 engineering and technology, 010402 general chemistry, 021001 nanoscience & nanotechnology, Platinum nanoparticles, 01 natural sciences, 0104 chemical sciences, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, Biomaterials, Few layer graphene, Colloid and Surface Chemistry, [CHIM]Chemical Sciences, 0210 nano-technology, ComputingMilieux_MISCELLANEOUS
Abstract: The functionalization of carbon nanomaterials in controlled and selective manner and in order to stabilize small metal nanoparticles is of high interest particularly in the catalysis field. We present the μ-waves assisted few layer graphene (FLG) oxidation in water, which results in a partial sheets exfoliation and formation of oxygen functionalized carbon nanoballs, supported on highly graphitized graphene sheets. This double morphology material allows homogenous anchoring of Pt nanoparticles, while the advantages of planar and highly crystallized FLG are preserved. For comparison, acid treated FLG (conventional heating) exhibits highly hydrophobic and inert surface with carboxylic groups as anchoring sides localized at the FLG edges. Despite similar oxygen content, the performed physicochemical analyses depict different nature and localization of the oxygen/defects functionalities introduced in water (in μ-waves) and acid treated FLGs. Finally, the addition of FLG during the preparation of Pt particles-carried out by μ-wave assisted polyol method yields small nanoparticles with average size of 1nm.
Published: 2015
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45. A highly N-doped carbon phase 'dressing' of macroscopic supports for catalytic applications

Author: Florian Banhart, Giuliano Giambastiani, Marc J. Ledoux, Cuong Duong-Viet, Dominique Begin, Won Hui Doh, Lam Nguyen-Dinh, Spyridon Zafeiratos, Housseinou Ba, Yuefeng Liu, Cuong Pham-Huu, Izabela Janowska, Pascal Granger, Walid Baaziz, Jean-Mario Nhut, Lai Truong-Phuoc, Tung Tran-Thanh, Xiaoke Mu, and Giulia Tuci
Subjects: Materials science, Renewable energy technology, Doped carbon, Metals and Alloys, Nanotechnology, General Chemistry, Raw material, Catalysis, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, N-doping, heterogeneous catalysis, ORR, H2S desulfurization, Phase (matter), Materials Chemistry, Ceramics and Composites, Mesoporous material
Abstract: The straightforward ''dressing'' of macroscopically shaped supports (i.e. b-SiC and a-Al2O3) with a mesoporous and highly nitrogen-doped carbon-phase starting from food-processing raw materials is described. The as-prepared composites serve as highly efficient and selective metal-free catalysts for promoting industrial key-processes at the heart of renewable energy technology and environmental protection.
Published: 2015
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46. Ferrocenyl D–π–A conjugated polyenes with 3-dicyanomethylidene-1-indanone and 1,3-bis(dicyanomethylidene)indane acceptor groups: Synthesis, linear and second-order nonlinear optical properties and electrochemistry

Author: Janusz Zakrzewski, Marcin Palusiak, Izabela Janowska, Henryk Scholl, Marcin Walak, Keitaro Nakatani, Department of Organic Chemistry, Łódź University of Technology, Laboratoire de Photophysique et Photochimie Supramoléculaires et Macromoléculaires (PPSM), and École normale supérieure - Cachan (ENS Cachan)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Cyclic voltammetry, Electronic absorption spectra, 3-bis(dicyanomethylidene)indane, Indane, Hyperpolarizability, Electron donor, Conjugated system, 010402 general chemistry, Photochemistry, 01 natural sciences, Biochemistry, Inorganic Chemistry, chemistry.chemical_compound, 3-Dicyanomethylidene-1-indanone and 1, Materials Chemistry, Molecule, Physical and Theoretical Chemistry, 010405 organic chemistry, Chemistry, Organic Chemistry, Chromophore, Acceptor, EFISH, 0104 chemical sciences, Crystallography, Ferrocene, X-ray structure, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], NLO-chromophore
Abstract: International audience; Second-order nonlinear optical chromophores incorporating the ferrocenyl group as an electron donor and 3-dicyanomethylidene- 1-indanone and 1,3-bis(dicyanomethylidene)indane acceptor groups, connected by a conjugated polyenic bridge of varied length (2[n] and 3[n], respectively) have been synthesized. The electronic absorption spectra of these compounds display in the visible region bands attributable to p–p* and metal-to ligand charge transfer (MLCT) transitions. The energies of these transitions are close to those reported earlier for ferrocenyl D–p–A chromophores with the strongest acceptor groups, e.g., with the 3-dicyanomethylidene-2,3-dihydrobenzothiophene- 1,1-dioxide group (1[n]) [V. Alain, M. Blanchard-Desce, C.-T. Chen, S.R. Marder, A. Fort, M. Barzoukas, Synt. Met. 81 (1996) 133]. The solid-state structure of 2[3], determined by X-ray diffraction shows a significant reduction of the bond length alternation (BLA), 0.05A ˚ , suggesting high first hyperpolarizability. However, a centrosymmetrical packing of molecules of this compound in the crystal excludes its second harmonic generation ability. The lb values of 2[n] and 3[n], determined by the EFISH technique at 1907 nm are high and increase with the increasing length of the conjugated p-bridge. The highest value of lb (8720 · 1048 esu) was determined for 3[4], which is close to that reported for 1[4] (11200 · 1048 esu), the highest value found for a ferrocenyl D–p–A chromophore until now.
Published: 2006
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47. FLG–high aspect ratio MWNTs hybrid film prepared by hot spray technique

Author: Antoine Bonnefont, Nicolas Macher, Dominique Begin, Izabela Janowska, Rusoma Akilimali, and Cuong Pham-Huu
Subjects: Materials science, Mechanical Engineering, Carbon nanotube, Conductivity, Condensed Matter Physics, law.invention, Few layer graphene, Mechanics of Materials, law, Percolation, General Materials Science, Composite material, Carbon nanomaterials, Sheet resistance
Abstract: Few layer graphene (FLG)–multiwall carbon nanotubes (MWNTs) hybrid films were prepared using the hot spray technique. In order to increase the connectivity between FLG species, multiwall carbon nanotubes with high aspect ratio were applied. Much higher percolation inside the hybrid was observed, compared to the mono-material films (FLG or MWNTs). The “conductivity of transparency” value was almost 50 times higher for the FLG–MWNTs film than that for the FLG alone and the sheet resistance is 15 kΩ/sq at 86% of transparency for this hybrid.
Published: 2013
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48. Synthesis and Structure of a Four-Coordinate Aluminum Alkyl Cation/HB(C6F5)3 Salt: Implication in a B(C6F5)3-Catalyzed Hydroalumination Reaction of Benzophenone or Benzaldehyde

Author: and Janusz Zakrzewski, Gérard Jaouen, Izabela Janowska, Richard Welter, and Samuel Dagorne
Subjects: chemistry.chemical_classification, Hydride, Stereochemistry, Organic Chemistry, Borohydride, Medicinal chemistry, Catalysis, Inorganic Chemistry, Benzaldehyde, chemistry.chemical_compound, chemistry, Isobutane, Benzophenone, Reactivity (chemistry), Physical and Theoretical Chemistry, Alkyl
Abstract: The reaction of the bulky aminophenol 2-(CH2NMe2)-4-Me-6-CPh3-C6H3OH (1) with Al(iBu)3 yields via isobutane elimination the formation of the diisobutyl Al complex {6-(CH2NMe2)-2-CPh3-4-Me-C6H2O}Al(iBu)2 (2) in high yield. Reaction of 2 with B(C6F5)3 in the presence of NMe2Ph affords, along with isobutene, the salt compound [{6-(CH2NMe2)-2-CPh3-4-Me-C6H2O}Al(iBu)(NMe2Ph)][HB(C6F5)3] (3), consisting of a four-coordinate Lewis acidic Al cation associated with the borohydride HB(C6F5)3-, whose solid-state structure was determined by X-ray crystallography. When complex 2 is reacted with B(C6F5)3 (1 and 0.05 equiv) in the presence of benzophenone and benzaldehyde, the quantitative conversion to the hydroalumination products 4 and 5, respectively, is observed. This B(C6F5)3-catalyzed hydroalumination reaction, via a B(C6F5)3-mediated hydride abstraction/transfer reaction, represents a new type of reactivity for Al alkyl cations and illustrates the higher reactivity of Al cation/HB(C6F5)3- salts versus the classi...
Published: 2004
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49. Ferrocenyl D-π-A chromophores containing 3-dicyanomethylidene-1-indanone and 1,3-bis(dicyanomethylidene)indane acceptor groups

Author: Henryk Scholl, Jacques A. Delaire, Janusz Zakrzewski, Keitaro Nakatani, Marcin Palusiak, Marcin Walak, and Izabela Janowska
Subjects: Steric effects, Stereochemistry, Organic Chemistry, Indane, Chromophore, Biochemistry, Medicinal chemistry, Acceptor, Inorganic Chemistry, chemistry.chemical_compound, Nonlinear optical, Ferrocene, chemistry, Materials Chemistry, Physical and Theoretical Chemistry, Cyclic voltammetry
Abstract: The nonlinear optical properties of ferrocenyl (Fc) D-π-A chromophores containing powerful 3-dicyanomethylidene-1-indanone (2) and 1,3-bis(dicyanomethylidene)indane-based acceptor group (3) have been measured by EFISH technique at 1.907 μm and compared with those reported for the Fc compound containing the 3-dicyanomethylidene-2,3-benzo[b]thiophen-1,1-dioxide group (1). The values of μβ·(2ω) are 160 and 280×10−48 esu for 2 and 3, respectively, whereas 1 displays a value of 140×10−48 esu [Inorg. Chim. Acta 242 (1996) 43]. The X-ray crystallographic study of 1 and 2 revealed significant distortions of the structure of the ferrocene moieties due to the contribution of a charge-separated η6-fulvene mesomeric form and important steric effects. The cyclic voltammetry data showed an anodic shift of the Fe(II)/Fe(III) oxidation potentials of 2 and 3 in comparison to those of ferrocenecarboxaldehyde (4) and 2-(ferrocenylmethylidene)-1,3-indandione (5), and an approximately additive effect of the substitution of one or two carbonyl oxygens in 5 by the C(CN)2 group.
Published: 2003
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50. High yield graphene and few-layer graphene synthesis assisted by microwaves

Author: Kambiz Chizari, Izabela Janowska, Maria Simona Moldovan, Cuong Pham-Huu, Ovidiu Ersen, Marc J. Ledoux, Dominique Begin, Institut de chimie et procédés pour l'énergie, l'environnement et la santé (ICPEES), Université de Strasbourg (UNISTRA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, and Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)
Subjects: Materials science, Nanotechnology, 02 engineering and technology, 010402 general chemistry, 01 natural sciences, law.invention, law, Graphite, ComputingMilieux_MISCELLANEOUS, Aerographene, Graphene oxide paper, [PHYS]Physics [physics], Spin coating, Graphene, Graphene foam, [CHIM.MATE]Chemical Sciences/Material chemistry, [CHIM.CATA]Chemical Sciences/Catalysis, 021001 nanoscience & nanotechnology, Condensed Matter Physics, Atomic and Molecular Physics, and Optics, 0104 chemical sciences, Electronic, Optical and Magnetic Materials, Chemical engineering, 0210 nano-technology, Layer (electronics), Graphene nanoribbons
Abstract: Graphene and few-layer graphene have been synthesized from expanded graphite under microwave irradiations in an aqueous ammonia solution. Yields as high as 8% have been obtained taking into account the precursor weight. The particle size is typically comprised between 0.2 and 0.5 mm with a graphene layer number not exceeding ten. Films have been realized by spin coating and their electrical conductivity strongly depends on the number of oxygenated groups, probably located at the edge of the graphene sheets.
Published: 2012
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