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2. Synthesis of TiO 2 /SBA-15 Nanocomposites by Hydrolysis of Organometallic Ti Precursors for Photocatalytic NO Abatement.

Author

El Atti, Ons, Hot, Julie, Fajerwerg, Katia, Lorber, Christian, Lebeau, Bénédicte, Ryzhikov, Andrey, Kahn, Myrtil, Collière, Vincent, Coppel, Yannick, Ratel-Ramond, Nicolas, Ménini, Philippe, and Fau, Pierre

Subjects
INDOOR air quality, AIR pollution, AIR quality, X-ray diffraction, TITANIUM dioxide, MESOPOROUS silica
Abstract

The development of advanced photocatalysts for air pollution removal is essential to improve indoor air quality. TiO2/mesoporous silica SBA-15 nanocomposites were synthesized using an organometallic decoration method, which leverages the high reactivity of Ti precursors to be hydrolyzed on the surface water groups of silica supports. Both lab-made Ti(III) amidinate and commercial Ti(IV) amino precursors were utilized to react with water-rich SBA-15, obtained through a hydration process. The hydrated SBA-15 and the TiO2/SBA-15 nanocomposites were characterized using TGA, FTIR, 1H and 29Si NMR, TEM, SEM, N2 physisorption, XRD, and WAXS. This one-step TiO2 decoration method achieved a loading of up to 51.5 wt.% of approximately 9 nm anatase particles on the SBA-15 surface. This structuring provided excellent accessibility of TiO2 particles for photocatalytic applications under pollutant gas and UV-A light exposure. The combination with the high specific surface area of SBA-15 resulted in the efficient degradation of 400 ppb of NO pollutant gas. Due to synergistic effects, the best nanocomposite in this study demonstrated a NO abatement performance of 4.0% per used mg of TiO2, which is 40% more efficient than the reference photocatalytic material TiO2 P-25. [ABSTRACT FROM AUTHOR]

Published
2024
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6. Ultra-High-Field 67Zn and 33S NMR Studies Coupled with DFT Calculations Reveal the Structure of ZnS Nanoplatelets Prepared by an Organometallic Approach

Author

Bellan, Ekaterina, primary, Maleki, Farahnaz, additional, Jakoobi, Martin, additional, Fau, Pierre, additional, Fajerwerg, Katia, additional, Lagarde, Delphine, additional, Balocchi, Andrea, additional, Lecante, Pierre, additional, Trébosc, Julien, additional, Xu, Yijue, additional, Gan, Zhehong, additional, Pautrot-d’Alençon, Lauriane, additional, Le Mercier, Thierry, additional, Nagashima, Hiroki, additional, Pacchioni, Gianfranco, additional, Lafon, Olivier, additional, Coppel, Yannick, additional, and Kahn, Myrtil L., additional

Published
2023
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7. Comparison of Photocatalytic Biocidal Activity of TiO2, ZnO and Au/ZnO on Escherichia coli and on Aspergillus niger under Light Intensity Close to Real-Life Conditions

Author

Al Hallak, Mohamad, primary, Verdier, Thomas, additional, Bertron, Alexandra, additional, Castelló Lux, Kevin, additional, El Atti, Ons, additional, Fajerwerg, Katia, additional, Fau, Pierre, additional, Hot, Julie, additional, Roques, Christine, additional, and Bailly, Jean-Denis, additional

Published
2023
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10. Ultra-High-Field 67Zn and 33S NMR Studies Coupled with DFT Calculations Reveal the Structure of ZnS Nanoplatelets Prepared by an Organometallic Approach.

Author

Bellan, Ekaterina, Maleki, Farahnaz, Jakoobi, Martin, Fau, Pierre, Fajerwerg, Katia, Lagarde, Delphine, Balocchi, Andrea, Lecante, Pierre, Trébosc, Julien, Xu, Yijue, Gan, Zhehong, Pautrot-d'Alençon, Lauriane, Le Mercier, Thierry, Nagashima, Hiroki, Pacchioni, Gianfranco, Lafon, Olivier, Coppel, Yannick, and Kahn, Myrtil L.

Published
2023
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11. Gas Sensing Properties of CuWO 4 @WO 3 n-n Heterojunction Prepared by Direct Hydrolysis of Mesitylcopper (I) on WO 3 ·2H 2 O Nanoleaves.

Author

Jońca, Justyna, Castello-Lux, Kevin, Fajerwerg, Katia, Kahn, Myrtil L., Collière, Vincent, Menini, Philippe, Sówka, Izabela, and Fau, Pierre

Subjects
ELECTRONIC noses, HETEROJUNCTIONS, TUNGSTEN trioxide, GAS detectors, COMPOSITE materials, SCHOTTKY barrier diodes, HYDROLYSIS
Abstract

The nanometer size Cu2O@WO3·H2O composite material has been prepared by the direct hydrolysis of mesitylcopper (I) on WO3·2H2O nanoleaves. The synthesis has been performed in toluene without the addition of any ancillary ligands. The prepared nanocomposite has been deposited as a gas-sensitive layer on miniaturized silicon devices and heated up gradually to 500 °C in the ambient air. During the heating, the CuWO4 phase is formed upon the reaction of Cu2O with the WO3 support as revealed by the XRD analyses. The as-prepared CuWO4@WO3 sensors have been exposed to 10 ppm of CO or 0.4 ppm of NO2 (RH = 50%). At the operating temperature of 445 °C, a normalized response of 620% towards NO2 is obtained whereas the response to CO is significantly lower (S = 30%). Under these conditions, the sensors prepared either with pristine CuO or WO3 nanostructures are sensitive to only one of the two investigated gases, i.e., CO and NO2, respectively. Interestingly, when the CuWO4@WO3 sensitive layer is exposed to UV light emitted from a 365 nm Schottky diode, its sensitivity towards CO vanishes whereas the response towards NO2 remains high. Thus, the application of UV illumination allowed us to modify the selectivity of the device. This new nanocomposite sensor is a versatile sensitive layer that will be integrated into a gas sensor array dedicated to electronic nose platforms. [ABSTRACT FROM AUTHOR]

Published
2023
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13. Towards Selective and Sensitive Detection of Carbon Monoxide with CuO/ZnO Heterojunction NanocompositePrepared by an Organometallic Approach

Author

Jońca, Justyna, Fajerwerg, Katia, Kahn, Myrtil, Menini, Philippe, Sówka, Izabela, Fau, Pierre, Wroclaw University of Science and Technology, Laboratoire de chimie de coordination (LCC), Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), 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), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Équipe MICrosystèmes d'Analyse (LAAS-MICA), Laboratoire d'analyse et d'architecture des systèmes (LAAS), Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT), Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut de Chimie de Toulouse (ICT), Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Fédération de recherche « Matière et interactions » (FeRMI), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), and European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grantagreement No 101033564

Subjects
CuO/ZnO nanocomposite, Organometallic approach CuO/ZnO nanocomposite Heterojunction MOS gas sensors, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Heterojunction, Organometallic approach, MOS gas sensors
Abstract

International audience; Nanometer size p-n heterojunction has been created from CuO and ZnO anisotropic nanoparticles prepared by a one-pot organometallic approach. The method is based on the hydrolysis or oxidation of an adequate metal-organic precursors in pure octylamine. The CuO and ZnO nanostructures were dispersed in ethanol and then, mixed at different mass ratios, i.e. CuO(75%)/ZnO(25%), CuO(50%)/ZnO(50%) and CuO(25%)/ZnO(75%). Finally, the CuO and ZnO suspensions and their mixtures were deposited on miniaturized gas sensors substrates by an ink-jet printing method and heated up gradually to 550 oC in ambient air. Then, the as-prepared sensors have been exposed to CO (100 ppm), C3H8 (100 ppm) and NH3 (5 ppm) at different working temperatures (from 75 oC to 400 oC) and under 50 % of relative humidity (RH). Among all prepared sensors the one based on the mixture of CuO (75 %) and ZnO (25 %) presents a very sensitive and selective response to CO. Indeed, at the operating temperature of 165 oC, a high sensitivity towards CO was obtained (SCO=624 %). In these conditions, the sensor exhibited low sensitivity to other tested gases (KCO/C3H8= 14.5 and KCO/NH3= 26) but its response time was quite long (t90=2.3 min) and the recovery was very sluggish (t10>20 min). Therefore, it was better to increase the working temperature up to 300 oC. Although the sensitivity and selectivity towards CO worsened (SCO=177%, KCO/C3H8= 4.7 and KCO/NH3= 9.8) the response/recovery time decreased to 50 s/4.5 min. The gas sensing performances of the CuO(75%)/ZnO(25%) composite was attributed to both high surface to volume ratio of the prepared nanostructures and the p-n heterojunction established between the CuO and ZnO nanoparticles.

Published
2022

17. Comparison of Photocatalytic Biocidal Activity of TiO 2 , ZnO and Au/ZnO on Escherichia coli and on Aspergillus niger under Light Intensity Close to Real-Life Conditions.

Author

Al Hallak, Mohamad, Verdier, Thomas, Bertron, Alexandra, Castelló Lux, Kevin, El Atti, Ons, Fajerwerg, Katia, Fau, Pierre, Hot, Julie, Roques, Christine, and Bailly, Jean-Denis

Subjects
LIGHT intensity, PHOTOCATALYSTS, TITANIUM dioxide, ESCHERICHIA coli, ASPERGILLUS niger, ZINC oxide, ASPERGILLUS
Abstract

Microbial contamination of the surface of building materials and subsequent release of microbial particles into the air can significantly affect indoor air quality. Avoiding the development or, at least, reducing the quantity of microorganisms growing on building materials is a key point to reduce health risks for building occupiers. In that context, the antimicrobial activity of TiO2, ZnO and Au/ZnO was assessed by measuring log reductions of Escherichia coli and Aspergillus niger populations both in the dark and under a light intensity close to real-life conditions. The bactericidal activities (≥2.3 log reduction) of tested products were stronger than their fungicidal activities (≤1.4 log reduction) after 2 h of contact. Different parameters including concentration of photocatalyst, intensity of light (dark vs. 5 W/m2 UV-A), and duration of contact between photocatalyst and microbial cells and spores were investigated. Results of this study confirmed bactericidal activities of TiO2, ZnO and AuZnO on E. coli and brought new insight on their fungicidal activity on the spores of A. niger. They also confirmed the greatest antimicrobial efficiency of ZnO compared to TiO2 and its increased photocatalytic activity when decorated with Au, leading to the highest log reductions detected after 2 h of contact for both tested microorganisms (4 and 1.4 for E. coli and A. niger, respectively). The antimicrobial activity was enhanced by the duration of contact between microorganisms and nanoparticles of the different tested photocatalytic products. [ABSTRACT FROM AUTHOR]

Published
2023
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23. Advanced Method for the Treatment of Organic Aqueous Wastes: Wet Peroxide Oxidation — WPO®, Laboratory Studies and Industrial Development

Author

Debellefontaine, Hubert, Falcon, Magali, Fajerwerg, Katia, Reilhac, Philippe, Striolo, Philippe, Foussard, Jean-Noël, Förstner, U., editor, Murphy, Robert J., editor, Rulkens, W. H., editor, Jain, Ravi K., editor, Aurelle, Yves, editor, Cabassud, Corinne, editor, Roustan, Michel, editor, and Shelton, Stephen P., editor

Published
1997
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24. Nano-Structuration of WO 3 Nanoleaves by Localized Hydrolysis of an Organometallic Zn Precursor: Application to Photocatalytic NO 2 Abatement.

Author

Castello Lux, Kevin, Fajerwerg, Katia, Hot, Julie, Ringot, Erick, Bertron, Alexandra, Collière, Vincent, Kahn, Myrtil L., Loridant, Stéphane, Coppel, Yannick, and Fau, Pierre

Subjects
*METALLIC oxides, *COMPOSITE materials, *ION recombination, *HYDROLYSIS, *NANOCOMPOSITE materials
Abstract

WO3 is a known photocatalytic metal oxide frequently studied for its depollution properties. However, it suffers from a high recombination rate of the photogenerated electron/holes pair that is detrimental to its performance. In this paper, we present a new chemical method to decorate WO3 nanoleaves (NLs) with a complementary metal oxide (ZnWO4) in order to improve the photocatalytic performance of the composite material for the abatement of 400 ppb NO2 under mild UV exposure. Our strategy was to synthesize WO3·2H2O nanoleaves, then, to expose them, in water-free organic solution, to an organometallic precursor of Zn(Cy)2. A structural water molecule from WO3·2H2O spontaneously decomposes Zn(Cy)2 and induces the formation of the ZnO@WO3·H2O nanocomposite. The material was characterized by electronic microscopy (SEM, TEM), TGA, XRD, Raman and solid NMR spectroscopies. A simple thermal treatment under air at 500 °C affords the ZnWO4@WO3 nanocomposite. The resulting material, additionally decorated with 1% wt. Au, presents a remarkable increase (+166%) in the photocatalytic abatement of NO2 under UV compared to the pristine WO3 NLs. This synthesis method paves the way to the versatile preparation of a wide range of MOx@WO3 nanocomposites (MOx = metal oxide). [ABSTRACT FROM AUTHOR]

Published
2022
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29. Detection and Discrimination of Formaldehyde with CuO/SnO2 dual layers MOS Gas Sensors Operated with a Pulsed Temperature Modulation

Author

Sendi, Aymen, Fau, Pierre, Fajerwerg, Katia, Kahn, Myrtil L., Menini, Philippe, Équipe MICrosystèmes d'Analyse (LAAS-MICA), Laboratoire d'analyse et d'architecture des systèmes (LAAS), Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées, Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT), Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), 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), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)

Subjects
pulsed temperature modulation, Formaldehyde, selectivity, metal oxides semiconductors, [SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics, indoor air quality, gas sensor
Abstract

International audience; In this work, the authors present a new approach to detect and discriminate sub-ppm level of formaldehyde with metal oxide semiconductors (MOS) gas sensors based on nanostructured layers of SnO2, CuO, or a combination of the two. These sensitive layers are deposited on silicon micro-hotplates and operated with a pulsed temperature modulation between 100 and 500°C under 50% of relative humidity (%RH). This method allows a very specific sensor response to formaldehyde compared to other gases such as CO or NO2. This sensor set up (combination of sensitive layers and pulsed temperature mode) opens the way toward an efficient formaldehyde detection method for indoor air quality applications.

Published
2020

31. MOX gas sensors obtained by mixing p-type and n-type metal oxides for air quality sensors

Author

Sendi, Aymen, Menini, Philippe, Bley, Vincent, Fajerwerg, Katia, Kahn, Myrtil L., Fau, Pierre, Équipe MICrosystèmes d'Analyse (LAAS-MICA), Laboratoire d'analyse et d'architecture des systèmes (LAAS), Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées, Matériaux Diélectriques dans la Conversion d’Energie (LAPLACE-MDCE), LAboratoire PLasma et Conversion d'Energie (LAPLACE), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), 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), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)

Subjects
silicon hot plate, metal oxide nanoparticle, [CHIM.MATE]Chemical Sciences/Material chemistry, [SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics, gas sensor
Abstract

International audience; Indoor air quality is major health concern in our societies and European recommendations (directive 2008/50/EC) will be fulfilled with the help of efficient air quality monitoring systems. MOX gas sensors have proven their interest for the air quality monitoring in open air or indoor areas.[1] The main drawbacks of these sensors concern their stability over time and their lack of selectivity among mixtures of gases as well as in variable humidity environment. If attention has been focused on n-type semiconducting oxides, few studies have been devoted to the p-type gas sensors. Among p-type oxide semiconductors, CuO have demonstrated considerable potential for detection of gases such C2H5OH, NO2, H2S, H2, CO and NH3.[2] The mixture of n-type and p-type metal oxides have been used to modify the response gas sensor,[3] but there is still a lack of knowledge about the role of n-p heterojunction to overcome the effect of the hygrometry changes. In order to increase the sensitivity and the selectivity of semi-conducting gas sensors, SnO2, WO3, CuO and ZnO nanopowders have been synthesized by a metalorganic approach. Efficient sensitive layers were prepared using mixed binary or ternary blends that were further integrated on silicon substrates. The optimum blending of different metal oxides (n-type and p-type) was achieved by mixing the nanopowders in an organic solvent. The mixed metal oxides have been prepared as a screen-printing paste and deposited on silicon micro hotplates.[4] The gas sensing performances will be presented and discussed.

Published
2019

36. From Organometallic Chemistry to Multifunctional Nanoparticle-Based Devices for Gas Detection and Degradation of Air Pollutants †.

Author

Jakoobi, Martin, Fajerwerg, Katia, and Kahn, Myrtil L.

Subjects
*ORGANOMETALLIC chemistry, *MATERIALS science, *AIR pollutants
Abstract

This document discusses the use of organometallic chemistry and nanoparticles in the development of multifunctional devices for gas detection and degradation of air pollutants. The authors emphasize the importance of addressing current global challenges and propose the design and synthesis of complex hybrid nano-objects and nanomaterials as a solution. They highlight the control and customization of nanoparticles through an organometallic approach, allowing for the synthesis of nanoparticles with specific properties. The authors also mention the implementation of these nanoparticles in gas sensors and air pollutant degradation devices. The research presented in this document spans multiple fields, including chemistry, physical chemistry, physics, and biology. [Extracted from the article]

Published
2024
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37. Ferroelectricity in Undoped ZnO Nanorods

Author

Centre National de la Recherche Scientifique (France), Maiz, Jon, Loxq, Pauline, Fau, Pierre, Fajerwerg, Katia, Kahn, Myrtil L., Fleury, Guillalume, Hadziioannou, Georges, Guegan, Guillaume, Majimel, Jérôme, Maglione, Mario, Rodriguez, Vincent, Pavlopoulou, Eleni, Centre National de la Recherche Scientifique (France), Maiz, Jon, Loxq, Pauline, Fau, Pierre, Fajerwerg, Katia, Kahn, Myrtil L., Fleury, Guillalume, Hadziioannou, Georges, Guegan, Guillaume, Majimel, Jérôme, Maglione, Mario, Rodriguez, Vincent, and Pavlopoulou, Eleni

Abstract

The technological interest in developing novel functional nano-objects that exhibit new properties arising from their nanoscopic nature is undoubtful. Although bulk ZnO is considered to be non-ferroelectric, herein, the ferroelectric behavior of undoped and self-standing ZnO nanoparticles is reported for the first time. The nanoparticles (NPs) under study are synthesized by an organometallic approach. When dispersed in a PMMA dielectric matrix, clear polarization loops and antisymmetric switching currents are recorded for the NPs with the larger volume, in coherence with the significant polar response of these NPs in solution, measured by polarization-resolved second harmonic scattering experiments. Structural characterizations reveal that ferroelectricity is related to the appearance of a new hexagonal crystalline phase, its unit cell being swelled with respect to the well-known wurtzite ZnO cell. The volume fraction of this new phase, the polar SHS response, and the amount of ferroelectric polarization response are all linearly linked, underlining the consistency between these complementary physical characterizations.

Published
2019

41. Detection and Discrimination Methods of Sub-ppm Nitrogen Dioxide (NO2) with a Copper Oxide Sensor Operated with a Pulsed Temperature Modulation

Author

Sendi, Aymen, Besnard, Grérory, Menini, Philippe, Talhi, Chaabane, Blanc, Frédéric, Franc, Bernard, Kahn, Myrtil L., Fajerwerg, Katia, Fau, Pierre, Équipe MICrosystèmes d'Analyse (LAAS-MICA), Laboratoire d'analyse et d'architecture des systèmes (LAAS), Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées, Service Instrumentation Conception Caractérisation (LAAS-I2C), Service Informatique : Développement, Exploitation et Assistance (LAAS-IDEA), Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT), Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), 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), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)

Subjects
CuO nanoparticles, selectivity, temperature modulation, [SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics, NO2, CuO nanoparticules, gas sensor
Abstract

International audience; NO2 is considered among the main pollutants found in atmosphere and indoor air as well. The exposure to this gas is dangerous to human health; its detection is an urgent need that requires the development of efficient and cheap methods and techniques for detection and data processing. In this context, copper oxide is a good candidate metal oxide that is sensitive and selective for NO 2 at sub-ppm concentrations. We used a CuO composed by nanoparticles deposited by inkjet printing technology on a micro hotplate. The optimum detection capacity is obtained thanks to a dedicated temperature modulation. Thanks to this operating mode, we report a simple method for data processing and exploitation in order to obtain a good selectivity for the nitrogen dioxide over few interferent gases. Only four parameters get from sensor response allow us to make an efficient discrimination between individual gases but also in gaseous mixtures in humid atmosphere.

Published
2018

42. Sub-ppm Nitrogen Dioxide (NO 2 ) Sensor Based on Inkjet Printed CuO on Microhotplate with a Pulsed Temperature Modulation

Author

Sendi, Aymen, Besnard, Grérory, Menini, Philippe, Talhi, Chabane, Blanc, Frédéric, Franc, Bernard, Kahn, Myrtil L., Fajerwerg, Katia, Fau, Pierre, Équipe MICrosystèmes d'Analyse (LAAS-MICA), Laboratoire d'analyse et d'architecture des systèmes (LAAS), Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT), Service Instrumentation Conception Caractérisation (LAAS-I2C), Service Informatique : Développement, Exploitation et Assistance (LAAS-IDEA), Laboratoire de chimie de coordination (LCC), Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), 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), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), IARIA, Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées, Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Équipe MICrosystèmes d'Analyse ( LAAS-MICA ), Laboratoire d'analyse et d'architecture des systèmes [Toulouse] ( LAAS ), Institut National Polytechnique [Toulouse] ( INP ) -Institut National des Sciences Appliquées - Toulouse ( INSA Toulouse ), Institut National des Sciences Appliquées ( INSA ) -Institut National des Sciences Appliquées ( INSA ) -Université Paul Sabatier - Toulouse 3 ( UPS ) -Centre National de la Recherche Scientifique ( CNRS ) -Institut National Polytechnique [Toulouse] ( INP ) -Institut National des Sciences Appliquées - Toulouse ( INSA Toulouse ), Institut National des Sciences Appliquées ( INSA ) -Institut National des Sciences Appliquées ( INSA ) -Université Paul Sabatier - Toulouse 3 ( UPS ) -Centre National de la Recherche Scientifique ( CNRS ), Service Instrumentation Conception Caractérisation ( LAAS-I2C ), Service Informatique : Développement, Exploitation et Assistance ( LAAS-IDEA ), Laboratoire de chimie de coordination ( LCC ), and Centre National de la Recherche Scientifique ( CNRS )

Subjects
CuO nanoparticles, selectivity, temperature modulation, [ SPI.NANO ] Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics, NO 2, [SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics, gas sensor
Abstract

International audience; Nitrogen dioxide (NO 2), a toxic oxidizing gas, is considered among the main pollutants found in atmosphere and indoor air as well. Since long-term or short-term exposure to this gas is deleterious for human health, its detection is an urgent need that requires the development of efficient and cost effective methods and techniques. In this context, copper oxide (CuO) is a good candidate that is sensitive and selective for NO 2 at sub-ppm concentrations. In this work, CuO nanoparticles have been deposited by inkjet printing technology on a micro hotplate that can be operated up to 500°C at low power consumption (55 mW). The optimum detection capacity is obtained thanks to a temperature modulation (two-consecutive temperature steps from 100°C to 500°C), where the sensing resistance is measured. Thanks to this operating mode, we report in this study a very simple method for data processing and exploitation in order to obtain a good selectivity for the nitrogen dioxide over few interferent gases. Only four parameters from the sensor response allow us to make an efficient discrimination between individual or mixed gases in humid atmosphere.

Published
2018

43. Nanoparticules d’or pour susciter des rencontres entre science et société

Author

Fajerwerg, Katia, Remita, Hynd, Pluchery, Olivier, Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), 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 Université Pierre et Marie Curie - Paris 6 (UPMC)

Subjects
[CHIM.COOR]Chemical Sciences/Coordination chemistry
Abstract

International audience; En raison de sa couleur et de ses propriétés de métal noble, l’or a depuis toujours été un élément de fascination et de convoitise. Des démonstrations avec des nanoparticules d’or se prêtent bien aux actions de formation et de dissémination des sciences. Des expériences faciles et ludiques peuvent montrer au grand public comment les propriétés changent à l’échelle nanométrique avec la taille et la forme et expliquer les applications des nanoparticules d’or dans plusieurs domaines. Différentes actions ont été menées par des scientifiques de la Société Chimique de France, de la Société Française de Physique, des C’Nano ou du GDR Or-Nano pour proposer des ateliers destinés à présenter les nanoparticules d’or et introduire les nanosciences au sein des lycées ou des universités, dans des expositions ou des musées. Ce partage de connaissances permet d’informer le grand public, de susciter des curiosités et parfois même des vocations chez les plus jeunes. Pour le chercheur, les actions de dissémination lui permettent à travers la communication et les échanges d’aller au-delà de ses propres recherches, et l’amènent parfois à de nouvelles interrogations.

Published
2018

44. Est-ce que l'expérience favorise l'apprentissage ?

Author

BOULC'H, Florence, Fajerwerg, Katia, Matériaux divisés, interfaces, réactivité, électrochimie (MADIREL), Aix Marseille Université (AMU)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SHS.EDU]Humanities and Social Sciences/Education, [CHIM]Chemical Sciences, ComputingMilieux_MISCELLANEOUS, [SHS]Humanities and Social Sciences
Abstract

International audience

Published
2018

45. Ferroelectricity in Undoped ZnO Nanorods

Author

Maiz, Jon, primary, Loxq, Pauline, additional, Fau, Pierre, additional, Fajerwerg, Katia, additional, Kahn, Myrtil L., additional, Fleury, Guillaume, additional, Hadziioannou, Georges, additional, Guegan, Guillaume, additional, Majimel, Jérôme, additional, Maglione, Mario, additional, Rodriguez, Vincent, additional, and Pavlopoulou, Eleni, additional

Published
2019
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