Download or read book Synth se par voie catalytique et purification de nanotubes de carbone written by Jean-François Colomer and published by . This book was released on 2000 with total page 422 pages. Available in PDF, EPUB and Kindle. Book excerpt: CE TRAVAIL A POUR OBJECTIF DE PRODUIRE DES NANOTUBES FULLERENIQUES, MULTI ET MONO-PAROIS, PAR DECOMPOSITION D'HYDROCARBURES SUR DES CATALYSEURS METALLIQUES SUPPORTES. LA SYNTHESE DES NANOTUBES MULTIPAROIS A ETE REALISEE SUR UN CATALYSEUR 2,5% CO/NAY. LES PARAMETRES DE REACTION ONT ETE OPTIMISES AFIN D'OBTENIR LES NANOTUBES EN QUANTITE SUFFISANTE POUR METTRE AU POINT UNE METHODE DE PURIFICATION EFFICACE. LES RENDEMENTS EN NANOTUBES PURS VARIENT ENTRE 27 ET 40% SELON LA METHODE D'ELIMINATION DES IMPURETES CARBONEES UTILISEE. LA QUALITE DES NANOTUBES SYNTHETISES ET/OU PURIFIES A ETE VERIFIEE PAR MICROSCOPIE ELECTRONIQUE A TRANSMISSION, BASSE ET HAUTE RESOLUTION. LA SYNTHESE DES NANOTUBES MONOPAROI A NECESSITE LA RECHERCHE DE NOUVEAUX CATALYSEURS, AINSI QUE DES CONDITIONS DE SYNTHESE OPTIMALES. DES CATALYSEURS A BASE DES METAUX USUELS (CO, FE, NI) SUPPORTES SUR ALUMINE OU SUR SILICE ONT PERMIS DE SYNTHETISER DES NANOTUBES MONOPROI PAR DECOMPOSITION D'ETHYLENE A HAUTE TEMPERATURE (1080\C). CEUX-CI ONT ETE CARACTERISES EN MICROSCOPIE ELECTRONIQUE. MALHEUREUSEMENT, MEME APRES OPTIMISATION DES PARAMETRES DE REACTION AVEC L'UTILISATION D'UN MELANGE METHANE/HYDROGENE, POUR EVITER LA PRODUCTION DE CARBONE AMORPHE, SEULES DE TRES FAIBLES QUANTITES DE NANOTUBES ONT ETE PRODUITES. L'EMPLOI DE NOUVEAUX CATALYSEURS, PREPARES SUR UN SUPPORT D'OXYDE DE MAGNESIUM, DONNE PAR CONTRE DES RENDEMENTS PLUS ELEVES, DE L'ORDRE DE 6 A 9% EN MASSE. APRES CARACTERISATION DES NANOTUBES MONOPAROI SYNTHETISES, EN MICROSCOPIE ELECTRONIQUE ET EN SPECTROSCOPIE RAMAN, ET UNE COMPARAISON AVEC CEUX PRODUITS PAR ARC ELECTRIQUE, LES PARAMETRES DE REACTION ONT ETE REOPTIMISES POUR CES CATALYSEURS.

Download or read book Nanohybrid Catalyst based on Carbon Nanotube written by Rasel Das and published by Springer. This book was released on 2017-05-23 with total page 159 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book introduces carbon nanotubes as a matrix for efficient nanohybrid catalysis. The preparation and use of such materials in ultra-grade water purification is described. Simple chemical methods for purification and functionalization of carbon nanotubes prior to their use is also detailed. The author also discusses the potential use of nanotube-based nanobiohybrid catalysts in the removal of organic pollutants.

Download or read book Synthesis and Purification of Carbon Nanotubes written by Syed Awais Rouf and published by . This book was released on 2020 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this chapter, we will evaluate the synthesis and purification of carbon nanotubes. Carbon nanotubes are cylindrical molecules that consists of graphene (rolled up of a single-layer carbon atom). A wide variety of synthesis techniques such as arc discharge synthesis, laser ablation of graphite/laser vaporization synthesis method, chemical vapor deposition (CVD), high pressure carbon monoxide synthesis and flame synthesis techniques, have been implemented to grow single and multi-walled carbon nanotubes for technological applications. All of the above methods exploit transition metals, like iron, cobalt, and nickel, as a catalyst. There are number of methods (filtering, chromatography and centrifugation) used to purify the carbon nanotubes, but the degree of purity remained questionable in these methods. In order to enhance the purification extent, alternate techniques such as Gas phase purification, Liquid phase purification and Purification by Intercalation are introduced. Here we will discuss the advantages and disadvantages of these purification routes. It will help researchers in selecting appropriate and effective method for synthesis and purification of carbon nanotubes.

Download or read book Synth se de nanotubes de carbone par CVD written by Julien Amadou and published by . This book was released on 2008 with total page 193 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Synthesis of Carbon Nanotubes on Carbon Supports and the Purification of Carbon Nanotubes written by Ali Rinaldi and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Synth se de nanoparticules m talliques monodispers s et croissance catalytique de nanotubes de carbone monofeuillets individuels written by Laurent Khuat Duy and published by . This book was released on 2005 with total page 240 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Synth se de nanotubes de carbone multi parois par d p t chimique en phase vapeur catalytique en lit fluidis written by Régis Philippe and published by . This book was released on 2006 with total page 272 pages. Available in PDF, EPUB and Kindle. Book excerpt: Produire à grande échelle des nanotubes de carbone en maîtrisant les principaux paramètres de croissance et la morphologie de ces matériaux est un enjeu important en vue de l’exploitation industrielle de ces matériaux nanostructurés dans de nombreux domaines tels que l’élaboration de composites ou le stockage d’énergie. C’est dans ce contexte que s’inscrit ce travail basé sur la technique de dépôt chimique en phase vapeur (CVD) mis en œuvre dans un procédé faisant appel à un lit fluidisé de particules catalytiques (FB-CCVD). Dans un premier temps, nous avons mis au point, testé et caractérisé plusieurs catalyseurs en faisant varier leur méthode de préparation, la phase active et le support. Ceci nous a permis de dégager et de sélectionner un catalyseur optimal en tenant compte des performances catalytiques rencontrées et des contraintes imposées par l’emploi d’un lit fluidisé. Le catalyseur retenu, est constitué de fer supporté sur un support d’alumine et est préparé également par dépôt chimique en phase vapeur en lit fluidisé, à partir de ferrocène, sous pression réduite et en présence d’air. Il conduit à l’obtention massive de nanotubes de carbone multiparois, alignés sur le support, constituant une gangue enrobant la surface des grains catalytiques. Par la suite, dans le cadre d’une étude cinétique, nous avons étudié l’influence des paramètres principaux de la réaction catalytique de formation des nanotubes de carbone à partir d’éthylène sur les caractéristiques physiques du lit fluidisé, l’efficacité du procédé et la qualité des nanotubes produits. Les informations cinétiques et morphologiques collectées, associées à un modèle de bullage de type Kato et Wen, ont ensuite permis l’élaboration d’un modèle global du réacteur de synthèse de nanotubes de carbone en lit fluidisé à partir de notre catalyseur. Ce modèle permet de prédire les performances du procédé en fonction des conditions expérimentales appliquées mais aussi l’évolution des caractéristiques physiques de la poudre composite obtenue. Enfin, dans une dernière partie, nous tentons de proposer une première explication du fonctionnement spécifique de notre catalyseur et de son évolution au cours de la synthèse des nanotubes de carbone alignés sur poudre.

Download or read book Etude Des Catalyseurs de Croissance de Nanotubes de Carbone Monoparois Synth tis s Par CVD written by Van Thang Le and published by . This book was released on 2008 with total page 199 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis is focussed on the chemical vapour deposition method to produce single wall carbon nanotubes. The purposes of this research are to understand exactly the role of the various chemical components presented in catalyst for the producing of SWNTs, to control process conditions, to develop synthesis techniques for SWNTs on pattemed catalyst that allow the integration for electronic devices and to transfer process to industrial CVD instrument. Experimental investigations are presented which allow getting a comprehensive picture of the powder catalyst growth of carbon nanotubes film. The role of each element in catalyst and the optimal amount of them are illustrated. Based on the electron microscopy, Raman spectroscopy, X-Ray diffraction, X-Ray photoelectron spectroscopy and microbalance results, a new component, (FexAly)(Alz-yFel-x)04, is detected. The (FexAly)(Alz-yFel-x)04 provides a key role to create active nanoparticles for carbon nanotubes growth.Subsequent studies of the properties of the produced carbon nanotubes grown by CVD reveal significant features of the product. Based on those experimental results, a mechanism for the growth of carbon nanotubes on the powder catalyst is suggested. Furthermore, a purification method of as-grown SWCNT has been developed that provides for the removal of catalyst nanoparticles and impurity carbon. We note that our purified product contain ~95% wt. carbon products.Complementary, by varying global growth parameters such as synthesis temperature, flow ratio of carbonaceouslhydrogen gas and growth time, this study attempts to control the process condition for the synthesis high yield of SWNTs. Furthermore, we present the results of the transfer of the synthesis process of SWNTs from the EASYTUBE system (small tubular CVD reactor) to industrial CENTURA tool (compatible wafer 200 mm) and the pattemed growth of SWNTs for electrical devices.

Download or read book Synth se et caract risations de supports de catalyseurs nano macro base de carbone et carbure de silicium written by Adrien Deneuve and published by . This book was released on 2010 with total page 213 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cette thèse a pour but de développer des supports de catalyseurs novateurs à base de carbone et de carbure de silicium. Le premier support est constitué de nanotubes de carbone macronisés sous forme de papier buvard (BP). Il possède les avantages liés aux propriétés des nanotubes de carbone comme un très haut rapport d’aspect. Ceux-ci confèrent au catalyseur BP+3%Fe2O3 des performances catalytiques supérieures à des catalyseurs plus classiques tel qu’un catalyseur similaire supporté sur le charbon actif (CA) pour la réaction d’oxydation de l’H2S en soufre élémentaire à pression atmosphérique. Le deuxième support est composé de carbure de silicium méso et macroporeux obtenu par synthèse à mémoire de forme. Cette structure poreuse contrôlée permet d’obtenir une activité catalytique dans la réaction d’oxydation d’H2S supérieure à celle obtenue avec un catalyseur similaire supporté sur alumine ou CA. De plus le SiC montre une résistance à l’oxydation moyenne qui peut être optimisée. Enfin, le dernier support étudié est un composite comportant un support hôte de SiC sur lequel on a fait croître des nanofibres de SiC. Ceci permet d’avoir les propriétés macroscopiques du support et les propriétés nanoscopiques des nanofibres de SiC. Par ailleurs, ce type de support montre une résistance à l’oxydation améliorée par rapport au SiC du fait de la croissance des nanofibres de SiC qui bloquent l’oxydation. D’autres améliorations de ces supports sont envisageables à l’aide de dopage par d’autres éléments.

Download or read book Les nanomat riaux et leurs applications pour l nergie lectrique written by NOËL Didier and published by Lavoisier. This book was released on 2014-01-10 with total page 474 pages. Available in PDF, EPUB and Kindle. Book excerpt: Les nanotechnologies apportent un fort potentiel d’innovation et de rupture dans de nombreux domaines. Leurs applications pour l’énergie en est un champ important, car la synthèse et la structuration des nanomatériaux y ouvrent des voies de progrès notables. Si divers ouvrages décrivent les innovations promises par les nanotechnologies sur des thématiques scientifiques générales ou spécialisées, très peu abordent le chemin qui va des nouvelles propriétés aux applications pour l’énergie électrique et ses usages. Cet ouvrage présente, sur des bases scientifiques solides, les apports des nanotechnologies et plus particulièrement des nanomatériaux aux enjeux de la production d’électricité et de ses usages. Après un panorama des effets physiques qui peuvent être exploités à ces échelles pour améliorer les propriétés des matériaux ou leur fonctionnalité, leur application à la production d’électricité, à son stockage, à ses usages ainsi qu’au traitement de questions environnementales est abordée. Elle conduit à explorer les domaines de l’électrochimie, du photovoltaïque, de la thermoélectricité, des propriétés mécaniques et thermiques des matériaux ou encore des membranes et des surfaces ultrahydrophobes. Chaque chapitre constitue une monographie exhaustive enrichie d’une abondante iconographie et d’une bibliographie très complète. Les meilleurs experts de chaque domaine ont été réunis, faisant de cet ouvrage une référence incontournable. Au confluent de plusieurs disciplines et en prise directe sur un vaste champ d’applications, ce livre s’adresse à un large public : ingénieurs et chercheurs, étudiants des écoles d’ingénieurs ou des universités aux niveaux licence et master.

Download or read book Graphene written by Wonbong Choi and published by CRC Press. This book was released on 2016-04-19 with total page 374 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since the late 20th century, graphene-a one-atom-thick planar sheet of sp2-bonded carbon atoms densely packed in a honeycomb crystal lattice-has garnered appreciable attention as a potential next-generation electronic material due to its exceptional properties. These properties include high current density, ballistic transport, chemical inertness,

Download or read book Carbon Filaments and Nanotubes Common Origins Differing Applications written by L.P. Biró and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 371 pages. Available in PDF, EPUB and Kindle. Book excerpt: Carbon filament, vapor grown carbon fibers and carbon nanotubes have been discovered to have remarkable properties, opening they way for their use in intriguing and novel applications in electronics, chemistry and materials science. There are many similarities between nanotubes and filaments, leading many researchers to critically compare the two materials, their production, and potential applications. The two materials are compared and contrasted in depth in the present book, which is a comprehensive review of current research activity, growth mechanisms, physical properties, industrial production, and applications. The structures are discussed using a unified approach, which helps to compare growth mechanisms, contrasting morphological differences, and detailing how novel properties depend on such differences.

Download or read book The Role of Catalysis for the Sustainable Production of Bio fuels and Bio chemicals written by Kostas Triantafyllidis and published by Newnes. This book was released on 2013-03-19 with total page 607 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Role of Catalysis for the Sustainable Production of Bio-fuels and Bio-chemicals describes the importance of catalysis for the sustainable production of biofuels and biochemicals, focused primarily on the state-of-the-art catalysts and catalytic processes expected to play a decisive role in the "green" production of fuels and chemicals from biomass. In addition, the book includes general elements regarding the entire chain of biomass production, conversion, environment, economy, and life-cycle assessment. Very few books are available on catalysis in production schemes using biomass or its primary conversion products, such as bio-oil and lignin. This book fills that gap with detailed discussions of: - Catalytic pyrolysis of lignocellulosic biomass - Hybrid biogasoline by co-processing in FCC units - Fischer-Tropsch synthesis to biofuels (biomass-to-liquid process) - Steam reforming of bio-oils to hydrogen With energy prices rapidly rising, environmental concerns growing, and regulatory apparatus evolving, this book is a resource with tutorial, research, and technological value for chemists, chemical engineers, policymakers, and students. - Includes catalytic reaction mechanism schemes and gives a clear understanding of catalytic processes - Includes flow diagrams of bench-, pilot- and industrial-scale catalytic processing units and demonstrates the various process technologies involved, enabling easy selection of the best process - Incorporates many tables, enabling easy comparison of data based on a critical review of the available literature

Download or read book Advances in Renewable Hydrogen and Other Sustainable Energy Carriers written by Abdallah Khellaf and published by Springer Nature. This book was released on 2020-08-19 with total page 517 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book examines a broad range of advances in hydrogen energy and alternative fuel developments and their role in the energy transition. The respective contributions were presented at the International Symposium on Sustainable Hydrogen, held in Algiers, Algeria on November 27-28, 2019. The transition from non-renewable polluting energy to sustainable green energy requires not only new energy sources but also new storage techniques and smart energy management. This situation has sparked renewed interest in hydrogen and alternative fuels, as they could help meet these needs. Indeed, hydrogen can not only be used as a clean energy vector or as an alternative fuel, but also as a storage medium or as an intermediary that enables improved energy management. This text offers a valuable reference guide for those working in the professional energy sector, as well as for students and instructors in academia who want to learn about the state of the art and future directions in the fields of hydrogen energy, alternative fuels and sustainable energy development.

Download or read book ICREEC 2019 written by Ahmed Belasri and published by Springer Nature. This book was released on 2020-06-10 with total page 659 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book highlights peer reviewed articles from the 1st International Conference on Renewable Energy and Energy Conversion, ICREEC 2019, held at Oran in Algeria. It presents recent advances, brings together researchers and professionals in the area and presents a platform to exchange ideas and establish opportunities for a sustainable future. Topics covered in this proceedings, but not limited to, are photovoltaic systems, bioenergy, laser and plasma technology, fluid and flow for energy, software for energy and impact of energy on the environment.

Download or read book Frontiers of Multifunctional Nanosystems written by Eugenia V. Buzaneva and published by Springer Science & Business Media. This book was released on 2002-05-31 with total page 504 pages. Available in PDF, EPUB and Kindle. Book excerpt: Proceedings of the NATO Advanced Research Workshop on Frontiers in Molecular-Scale Science and Technology of Fullerence, Nanotube, Nanosilicon, Biopolymer (DNA, Protein) Multifunctional Nanosystems, Kyiv, Ukraine, 9-12 September 2001

Download or read book Zeolites and Metal organic Frameworks written by Vincent Blay and published by . This book was released on 2018 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book examines Zeolites and Metal-Organic Frameworks. It explains the different synthetic routes available to prepare these materials, and examines how they are used by science and industry.