Academic literature on the topic 'Carbon xerogel'
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Journal articles on the topic "Carbon xerogel"
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Abdelwahab, Abdalla, Francisco Carrasco-Marín, and Agustín F. Pérez-Cadenas. "Carbon Xerogels Hydrothermally Doped with Bimetal Oxides for Oxygen Reduction Reaction." Materials 12, no. 15 (July 31, 2019): 2446. http://dx.doi.org/10.3390/ma12152446.
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A total of two carbon xerogels doped with cobalt and nickel were prepared by the sol–gel method. The obtained carbon xerogels underwent further surface modification with three binary metal oxides namely: nickel cobaltite, nickel ferrite, and cobalt ferrite through the hydrothermal method. The mesopore volumes of these materials ranged between 0.24 and 0.40 cm3/g. Moreover, there was a morphology transformation for the carbon xerogels doped with nickel cobaltite, which is in the form of nano-needles after the hydrothermal process. Whereas the carbon xerogels doped with nickel ferrite and cobalt ferrite maintained the normal carbon xerogel structure after the hydrothermal process. The prepared materials were tested as electrocatalysts for oxygen reduction reaction using 0.1 M KOH. Among the prepared carbon xerogels cobalt-doped carbon xerogel had better electrocatalytic performance than the nickel-doped ones. Moreover, the carbon xerogels doped with nickel cobaltite showed excellent activity for oxygen reduction reaction due to mesoporosity development. NiCo2O4/Co-CX showed to be the best electrocatalyst of all the prepared electrocatalysts for oxygen reduction reaction application, exhibiting the highest electrocatalytic activity, lowest onset potential Eonset of −0.06 V, and the lowest equivalent series resistance (ESR) of 2.74 Ω.
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Canal-Rodríguez, Maria, Ana Arenillas, Sara F. Villanueva, Miguel A. Montes-Morán, and J. Angel Menénedez. "Graphitized Carbon Xerogels for Lithium-Ion Batteries." Materials 13, no. 1 (December 26, 2019): 119. http://dx.doi.org/10.3390/ma13010119.
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Carbon xerogels with different macropore sizes and degrees of graphitization were evaluated as electrodes in lithium-ion batteries. It was found that pore structure of the xerogels has a marked effect on the degree of graphitization of the final carbons. Moreover, the incorporation of graphene oxide to the polymeric structure of the carbon xerogels also leads to a change in their carbonaceous structure and to a remarkable increase in the graphitic phase of the samples studied. The sample with the highest degree of graphitization (i.e., hybrid graphene-carbon xerogel) displayed the highest capacity and stability over 100 cycles, with values even higher than those of the commercial graphite SLP50 used as reference.
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Strachowski, Przemysław, Wojciech Kiciński, Maciej Fronczak, Waldemar Kaszuwara, Piotr Baranowski, and Michał Bystrzejewski. "An activation-free route to porous magnetic carbon adsorbents for the removal of phenolic compounds." New Journal of Chemistry 43, no. 27 (2019): 10792–802. http://dx.doi.org/10.1039/c9nj01981b.
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Magnetic composite carbon xerogels were synthesized via acidic gelation of resorcinol and furfural in the presence of carbon-encapsulated iron nanoparticles with subsequent carbonization of the as-obtained magnetic organic xerogel.
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Quach, Nguyen Khanh Nguyen, Wein-Duo Yang, Zen-Ja Chung, and Hoai Lam Tran. "The Influence of the Activation Temperature on the Structural Properties of the Activated Carbon Xerogels and Their Electrochemical Performance." Advances in Materials Science and Engineering 2017 (2017): 1–9. http://dx.doi.org/10.1155/2017/8308612.
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The effect of activation temperature on the structural properties and the electrochemical performance of KOH-activated carbon xerogel was investigated in range of 700 to 1000°C. At a high temperature (1000°C), the chemical activation regenerated a more crystalline network structure of activated carbon xerogels, which was observed by Raman, XRD, and TEM images. Additionally, SEM images, BET, BJH, and t-plot were used to study the structural properties of carbon xerogels. The carbon xerogel sample activated at 900°C was found with the most appropriate structure, which has the high micropore area and a more-balanced porosity between the micropores and mesopores, for using as an electrode material. The highest obtained specific capacitance value was 270 Fg−1 in 6 M KOH electrolyte at scan rate of 5 mVs−1 from the cyclic voltammetry.
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Eckert, Martin, Heena Suthar, and Jean-Francois Drillet. "Influence of Resorcinol to Sodium Carbonate Ratio on Carbon Xerogel Properties for Aluminium Ion Battery." Materials 15, no. 7 (April 1, 2022): 2597. http://dx.doi.org/10.3390/ma15072597.
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Carbon xerogels were synthesized using a soft-template route with resorcinol as the carbon source and sodium carbonate as the catalyst. The influence of the resorcinol to catalyst ratio in the range of 500–20,000 on pore structure, graphitic domains, and electronic conductivity of as-prepared carbon xerogels, as well as their performance in an aluminium ion battery (AIB), was investigated. After carbonization steps of the polymers up to 800 °C, all carbon samples exhibited similar specific volumes of micropores (0.7–0.8 cm³ g−1), while samples obtained from mixtures with R/C ratios lower than 2000 led to carbon xerogels with significantly higher mesopore diameters up to 6 nm. The best results, in terms of specific surface (1000 m² g−1), average pore size (6 nm) and reversible capacity in AIB cell (28 mAh g−1 @ 0.1 A g−1), were obtained with a carbon xerogel sample synthetized at a resorcinol to catalyst ratio of R/C = 500 (CXG500). Though cyclic voltammograms of carbon xerogel samples did not exhibit any sharp peaks in the applied potential window, the presence of both oxidation and a quite wide reduction peak in CXG500–2000 cyclic voltammograms indicated pseudocapacitance behaviour induced by diffusion-controlled intercalation/de-intercalation of AlCl4− ions into/from the carbon xerogel matrix. This was confirmed by shifting of the (002) peak towards lower 2θ angle values in the XRD pattern of the CXG500 electrode after the charging step in AIB, whereas the contribution of pseudocapacitance, calculated from half-cell measurements, was limited to only 6% of overall capacitance.
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Abdelwahab, Abdalla, Francisco Carrasco-Marín, and Agustín F. Pérez-Cadenas. "Binary and Ternary 3D Nanobundles Metal Oxides Functionalized Carbon Xerogels as Electrocatalysts toward Oxygen Reduction Reaction." Materials 13, no. 16 (August 10, 2020): 3531. http://dx.doi.org/10.3390/ma13163531.
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A series of carbon xerogels doped with cobalt, nickel, and iron have been prepared through the sol–gel method. The doped carbon xerogels were further functionalized with binary and ternary transition metal oxides containing Co, Ni, and Zn oxides by the hydrothermal method. A development in the mesopore volume is achieved for functionalized carbon xerogel doped with iron. However, in the functionalization of carbon xerogel with ternary metal oxides, a reduction in pore diameter and mesopore volume is found. In addition, all functionalized metal oxides/carbon are in the form of 3D nanobundles with different lengths and widths. The prepared samples have been tested as electrocatalysts for oxygen reduction reaction (ORR) in basic medium. All composites showed excellent oxygen reduction reaction activity; the low equivalent series resistance of the Zn–Ni–Co/Co–CX composite was especially remarkable, indicating high electronic conductivity. It has been established that the role of Zn in this type of metal oxides nanobundles-based ORR catalyst is not only positive, but its effect could be enhanced by the presence of Ni.
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Kraiwattanawong, Kriangsak. "Porous Properties of Carbon/Carbon Composite Xerogels." Materials Science Forum 928 (August 2018): 62–67. http://dx.doi.org/10.4028/www.scientific.net/msf.928.62.
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Carbon/carbon composite xerogels are prepared by a vacuum drying technique whereas a carbon cryogel is synthesized by a freeze drying technique to compare the effect of these drying methods at the selective synthesis condition. Resorcinol and formaldehyde are used to prepare a matrix phase and cotton fibers are acted as a disperse phase of the carbon/carbon composite xerogels. Here resorcinol and formaldehyde is utilized to synthesize the carbon cryogel only. The carbon/carbon composite xerogels and the carbon cryogel were analyzed by a nitrogen adsorption apparatus and a field emission scanning electron microscope. The results support that the vacuum drying can decrease the pore shrinkage despite of the gas-liquid interface. The porous properties of the carbon xerogel is quite equivalent to the porous properties of the carbon cryogel. When the porous properties of carbon xerogels are considered, their porous properties can be preserved at the high porosity until 0.15 g/g of the cotton fibers/resorcinol ratio. At 0.25 g/g of this ratio, the porous properties start decreasingly.
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Ayu Lestari, Riani, Muthia Elma, Erdina Lulu Atika Rampun, Anna Sumardi, Adhe Paramitha, Aptar Eka Lestari, Sadidan Rabiah, Zaini Lambri Assyaifi, and Gesit Satriaji. "Functionalization of Si-C Using TEOS (Tetra Ethyl Ortho Silica) as Precursor and Organic Catalyst." E3S Web of Conferences 148 (2020): 07008. http://dx.doi.org/10.1051/e3sconf/202014807008.
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Silica network was tailored configuring siloxane (Si-O-Si) and silanol (Si-OH) groups which are essential to produce porous-structured materials. As silanols are hydrophilic, react with water to form fouling. This research address to actualize strategy for synthesizing highly functionalized silica carbon (Si-C) using hybrid organic-inorganic structures as the primary method for improving hydro-stability by employing precursor TEOS and organic catalyst through a sol-gel process. Catalysis employs citric acid or citric acid-ammonia whereas carbon templated into silica network. The synthesis scheme involves: a) sol-gel process at 0°C and b) calcination. Silica sol dried into xerogels were prepared and calcined at 200°C and 250°C. Characterization of xerogels showed the infrared band areas of the organic groups to evaluate the thermal stability. For xerogel employed single (pH 5.5) and dual (pH 7.65) catalyst, infrared spectra showed mostly look similar Si-C area at similar wavelength. Silica xerogel is more effectively prepared from TEOS with one-step single acid catalyst including calcination.
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Wolfs, Cédric, Stéphanie D. Lambert, Alexandre F. Léonard, and Julien G. Mahy. "Custom-Shaped Carbon Xerogel Materials by 3D Printing." Processes 10, no. 10 (October 1, 2022): 1979. http://dx.doi.org/10.3390/pr10101979.
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Sol–gel-based carbon xerogels possess very promising properties for pollution abatement, using processes that associate adsorption and on-site electrochemical oxidation. However, combining a high exterior surface area (for efficient diffusion) and a monolithic shape (necessary for electrochemical processes) poses challenges. In this work, the shape of monolithic carbon xerogels was contrived by the use of 3D-printed molds. Several parameters were optimized: the choice of mold design, the choice of plastic, the 3D printer parameters, the solvent, and the process of dissolving the plastic. A design combining fine sticks and plates made of ABS was printed; a sol–gel carbon xerogel monolith was synthesized in it, and the mold was removed by using a combination of acetone and pyrolysis. Dissolving the plastic could be carried out by placing the material on a metallic net and leaving the dissolved ABS to settle. The resulting carbon material exhibits a high exterior surface area and good strength, leading to potential uses in the aforementioned process. The research shows that 3D printing is an efficient method of parameter optimization in pre-industrialization research, thanks to its flexibility, low cost, and ease of use.
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Mahato, Nihar Ranjan, Kamala Mandy Hansda, Ajit Das, Jayanta Banerjee, Sridhar Mondal, and Nagendranath Mahata. "Synthesis of Mesoporous Carbon Xerogel and Activation by Oxidative Treatment." Asian Journal of Chemistry 31, no. 10 (August 30, 2019): 2139–42. http://dx.doi.org/10.14233/ajchem.2019.22009.
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Synthesis of carbon xerogel and modification of its surface by various oxidative treatments are explored. Organic gel was synthesized by following the conventional sol-gel approach using formaldehyde and resorcinol. The wet gel was dried under subcritical condition and then carbonized, leading to carbon xerogel. Subsequently, the carbon xerogel was subjected to surface activation by means of oxidative treatment with nitric acid, sulphuric acid as well as aerial oxidation. Surface acid/base properties of the carbon xerogel have been strongly altered by treatments with nitric acid as well as with sulphuric acid. On the other hand, total surface area and pore volume have been significantly modified by air activation.
Dissertations / Theses on the topic "Carbon xerogel"
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Jivanescu, Iulia Elena. "Structure and performance of carbon xerogel molded emitters for micropropulsion applications." Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/105616.
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Thesis: S.M., Massachusetts Institute of Technology, Department of Aeronautics and Astronautics, 2016.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 91-94).
Ion electrospray propulsion relies on the transport of propellant to emission sites where ions and/or droplets are extracted to create thrust. The focus of this research is the creation of porous emitter substrates through which the liquid is passively transported. Previous substrates were created subtractively by selectively removing material to reveal emitter tips or arrays. The limitations of the previous substrates are pore size variability, non-uniform emitter tips, and difficulty in creating identical tips. This study investigates the use of carbon xerogels for electrospray applications due to their exceptional properties such as large surface to volume ratio, robustness and pore uniformity. The substrates are created through a synthesis route which is advantageous for reproducibility. Single carbon xerogel emitter tips and emitter arrays are molded on previously synthesized carbon xerogel substrates. Molding is an additive method which allows for parallel processing and batch manufacturing. Initially carbon xerogels substrates are synthesized. Then a carbon xerogel emitter tip is molded on top of a previously synthesized carbon substrate. Finally, an array of resorcinol formaldehyde emitters is molded on top of a carbon substrate. The carbon xerogel substrate with a molded tip is tested for Retarding Potential Analysis and Time of Flight Mass Spectrometry measurements in order to determine fragmentation fractions and beam composition. The results are consistent with the ionic liquid EMI-BF4 fragmentation fractions and pure ionic regime is achieved. The beam is nearly monoenergetic and fragmentation occurs mostly outside the acceleration region which does not affect thruster efficiency.
by Iulia Elena Jivanescu.
S.M.
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Niu, Pengfei. "Carbon Xerogel nanocomposite materials for electrochemical devices: application to heavy metal detection." Doctoral thesis, Universitat Autònoma de Barcelona, 2015. http://hdl.handle.net/10803/309289.
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En aquesta Tesi es descriu la fabricació d’elèctrodes nanocompòsits de carboni porós en forma de capa prima i capa gruixuda i la seva aplicació en l’anàlisi de metalls pesants en aigües. Aquests nanocompòsits de carboni es van preparar a partir de la piròlisi de materials obtinguts per química sol-gel, concretament de gels de resorcinol-formaldehid i de resorcinol-formaldehid amb sílice, que contenien precursors de bismut.
Els gels pirolitzats presenten una estructura de carbó porós amb porositat oberta que conté nanopartícules de bismut ben distribuïdes. Aquests materials es van moldre fins a obtenir una pols de granulometria adequada per fer elèctrodes de pasta de carboni per ser estudiats al laboratori i elèctrodes serigrafiats de capa gruixuda de tipus comercial. Aquests elèctrodes presenten una resposta molt bona en l’anàlisi de metalls pesats en aigües. Els límits de detecció de Pb(II), Cd(II) i Ni(II) obtinguts amb aquest elèctrodes estan molt per sota de la concentracions màximes d’aquests metalls contemplades en les normatives d’aigua per al consum de la Unió Europea i els Estats Units (US-EPA). Es va dur a terme l’anàlisi de Pb(II), Cd(II), Ni(II), Zn(II) i Cu(II) en aigües reals de diferent origen i complexitat i es va veure que en la majoria de casos s’obtenien resultats que estaven d’acord amb les mesures fetes per espectroscòpia de masses. També es van estudiar les limitacions dels sensors desenvolupats i interferències entre els diferents analits.
Pel que fa als elèctrodes en capa prima, per spin-coating es van dipositar capes primes uniformes i contínues de sols de resorcinol-formaldehid que contenien un precursor de SiO2 sobre oblies de SiO2/Si de 4 polzades. Es va comprovar que després de la piròlisi l’adhesió de les capes de carboni sobre la capa de SiO2/Si millorava molt incorporant en el sol el precursor de SiO2. Els elèctrodes de carboni/sílice en capa prima es van fabricar utilitzant processos de fotolitografia i soft-lithography. Aquests elèctrodes no donaven cap resposta en voltamperometria cíclica en solucions de ferri/ferrocianur però en canvi si que ho feien amb una sonda redox de ferrocè. En el cas de les capes primes, la incorporació de nanopartícules de bismut seguint un procediment anàleg al de la síntesi dels gels macroscòpics resultava problemàtica degut a que durant la piròlisi s’evaporava tot el bismut. Tanmateix, aquests elèctrodes es van poder utilitzar amb èxit per a l’anàlisi de metalls pesants fent simultàniament la co-deposició electroquímica de bismut amb els metalls pesats analitzats.En esta Tesis se describe la fabricación de electrodos nanocompuestos de carbono poroso en forma de capa delgada y capa gruesa y su aplicación al análisis de metales pesados en aguas. Estos nanocompuestos de carbono se prepararon a partir de la pirolisis de materiales obtenidos por química sol-gel, concretamente de geles de resorcinol-formaldehído y de resorcinol-formaldehído con sílice, que contenían precursores de bismuto. Los geles pirolizados presentan una estructura de carbono poroso con porosidad abierta que contiene nanopartículas de bismuto bien distribuidas. Estos materiales se molieron hasta obtener granulometrías adecuadas para hacer electrodos de pasta de carbono para estudios de laboratorio y para hacer electrodos serigrafiados de capa gruesa de tipo comercial. Estos electrodos presentan una respuesta muy buena en el análisis de metales pesados en aguas, obteniéndose límites de detección de Pb(II), Cd(II) y Ni(II) que están muy por debajo de las concentraciones máximas contempladas por las normativas de agua para el consumo de la Unión Europea y Estados Unidos (US-EPA). Se llevaron a cabo análisis de Pb(II), Cd(II), Ni(II), Zn(II) y Cu(II) en aguas reales de diferente origen y complejidad y en la mayoría de casos se obtuvieron resultados en acuerdo con las medidas realizadas por espectroscopia de masas. Asimismo, se estudiaron las limitaciones de los sensores desarrollados y las interferencias entre los analitos. En relación a los electrodos en capa delgada, por spin-coating se depositaron capas uniformes y continuas de soles de resorcinol-formaldehído que contenían un precursor de SiO2 sobre obleas de SiO2/Si de 4 pulgadas. Se comprobó que después de la pirolisis la adhesión de las capas de carbono sobre la capa de SiO2/Si mejoraba mucho incorporando el precursor de SiO2en el sol. Los electrodos de carbono/sílice en capa delgada se fabricaron tanto por fotolitografía como por soft-lithography. Estos electrodos no presentaron respuesta alguna en voltamperometría cíclica en soluciones de ferri/ferrocianuro pero sí que lo hicieron en el caso de una sonda redox de ferroceno. En el caso de las capas delgadas, la incorporación de nanopartículas de Bi mediante un procedimiento análogo al seguido para la síntesis de los geles macroscópicos presentaba problemas debido a la evaporación de Bi durante la pirolisis. Sin embargo, estos electrodos se pudieron utilizar satisfactoriamente para el análisis de metales pesados haciendo una co-deposición electroquímica de Bi con los metales pesados analizados.
This Thesis describes the fabrication of both thick-film and thin-film electrodes with porous carbon nanocomposite materials and the application of these electrodes in the electrochemical analysis of heavy metals in aqueous solutions. These carbon composites were obtained from the pyrolysis of materials prepared by sol-gel chemistry approach, namely resorcinol-formaldehyde and resorcinol-formaldehyde /silica gels containing bismuth precursors. Bulk bismuth nanoparticle-carbon xerogel nanocomposite materials consist of an open porous structure of carbon with well distributed bismuth nanoparticles. These materials were ball-milled into powders of suitable size to produce conventional paste electrodes to be characterized in the lab and commercial-like screen printed thick-film electrodes. These electrodes display a superior performance in the sensitive stripping voltammetric detection of heavy metals in waters. The limit of detections for Pb(II), Cd(II) and Ni(II) obtained using these electrodes are well below the threshold concentrations established for drinking water quality by the EU and the US-EPA. The analysis of Pb(II), Cd(II), Ni(II), Zn(II) and Cu(II) have been performed in real waters of different origin and complexity, showing results in agreement with the standard mass spectroscopy method. The limitations of the developed electrodes and the interferences between different analytes were also investigated. In the case of thin film electrodes, large scale uniform and continuous carbon/silica films were deposited on 4-inch SiO2/Si wafers by spin-coating resorcinol-formaldehyde sols containing a SiO2 precursor. The interfacial adhesion between carbon films and SiO2/Si substrates is significantly enhanced by the addition of SiO2. Carbon/silica thin-film electrodes were fabricated by both photolithography and soft-lithography processes. These electrodes did not provide any cyclic voltamperometric signals in inner-sphere ferri-/ferrocyanide solutions but were successfully characterized in solutions containing outer-sphere ferrocene redox probe. The incorporation of bismuth nanoparticles into carbon/silica films during their sol-gel deposition stage is challenging due to the loss of bismuth by evaporation during pyrolysis step. Nevertheless, these electrodes were successfully applied for the detection of heavy metals by co-deposition of bismuth and heavy metals.
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Weber, Christian [Verfasser], Jens [Gutachter] Pflaum, and Jean [Gutachter] Geurts. "Electrochemical Energy Storage: Carbon Xerogel-Manganese Oxide Composites as Supercapacitor Electrode Materials / Christian Weber. Gutachter: Jens Pflaum ; Jean Geurts." Würzburg : Universität Würzburg, 2016. http://d-nb.info/1111785198/34.
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Santos, Ana Rita Martins dos. "Eletroinserção de íons lítio em matrizes auto-organizadas de V2O5, poli(etilenoimina) e nanopartículas de carbono." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/59/59138/tde-18092013-090848/.
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Materiais auto-organizados constituídos de V2O5 xerogel, poli(etilenoimina) (PEI) e nanopartículas de carbono (NpCs) foram obtidos por meio da técnica camada-por-camada (LbL). A metodologia aplicada permitiu a obtenção de filmes finos com elevado controle de espessura além de permitir um crescimento linear dos filmes, denominados neste trabalho V2O5/PEI e V2O5/PEI/NpCs. Além disso, o desempenho eletroquímico dos materiais auto-organizados foi comparado a um eletrodo de V2O5. Análises de FTIR mostraram que interações específicas entre os grupos amina do PEI e os grupos carboxila do V2O5 são responsáveis pelo crescimento do filme. Estas interações permitem a formação de um campo eletrostático capaz de blindar as interações entre os íons lítio e os oxigênios da vanadila (V=O) e, por consequência, são responsáveis pelo aumento na mobilidade iônica dos íons lítio no interior da matriz hospedeira e, portanto, um aumento na capacidade de armazenamento de carga. Resultados obtidos através de medidas de carga/descarga mostram que o V2O5/PEI/NpCs apresenta uma melhor desempenho do que os demais materiais estudados neste trabalho. Estes resultados mostram que a capacidade específica do V2O5/PEI/NpCs foi de 137 mA h g-1 para a menor densidade de corrente aplicada e aproximadamente 1,6 vezes maior do que os valores de capacidade específica para os outros materiais para a maior densidade de corrente aplicada. Além disso, estas medidas permitiram a observação de uma menor variação na razão estequiométrica máxima (xmáx) em função das densidades de corrente aplicadas para os filmes auto-organizados, fato este relacionado a uma maior mobilidade iônica dos íons lítio no interior dessas matrizes. Os resultados obtidos a partir de espectroscopia de impedância eletroquímica (EIS) mostraram que a difusão dos íons lítio no interior das matrizes auto-organizadas é maior do que no caso do V2O5, cujos valores do coeficiente de difusão foram de 1,64 x 10-15, 1,21 x 10-14 e 2,26 x 10-14 cm2 s-1 para os filmes V2O5, V2O5/PEI e V2O5/PEI/NpCs, respectivamente. Sendo assim, o polímero e as NpCs promoveram novos caminhos condutores e permitiram a conexão elétrica entre camadas isoladas da matriz V2O5. Dessa forma, novos nanocompósitos foram obtidos visando demonstrar o método de auto-organização empregado para melhorar o transporte de carga em matrizes hospedeiras.Self-assembled materials constituted of V2O5 xerogel, poly (ethyleneimine) (PEI), and carbon nanoparticles (CNPs) were obtained by the layer-by-layer (LbL) technique. The applied methodology permitted the obtainment of thin films with high thickness control and also permitted a linear growth of the films, which will be named V2O5/PEI and V2O5/PEI/CNPs. Besides, the electrochemical performance of the self-assembled materials was compared to a V2O5 electrode. FTIR analyses showed that the specific interactions between the amine groups of PEI and the vanadyl groups of the V2O5 are responsible for the film growth. These interactions permitted the formation of an electrostatic shield capable of hindering the interactions between the lithium ions and the vanadyl oxygen atoms (V=O) and are consequently responsible for the enhancement on the ionic mobility of the lithium ions within the host matrix, leading to a higher energy storage capability. Results obtained by the charge/discharge measurements showed that V2O5/PEI/CNPs presents a better performance than the other materials studied for this research. These results demonstrated that the specific capacity of the V2O5/PEI/CNPs was 137 mA h g-1 under the lowest current density applied and approximately 1.6 times higher than the specific capacity values obtained for the other materials under the highest current density applied. Moreover, it was observed that the variation of the maximum stoichiometric ratio (xmax) as a function of the current density is lower for the self-assembled materials than for the V2O5 electrode, which can be related to the higher ionic mobility of the lithium ion within the self-assembled materials. Electrochemical Impedance Spectroscopy (EIS) data demonstrated that the diffusion of the lithium ions within the self-assembled materials is higher than within the V2O5 electrode, and the diffusion coefficients were 1.64 x 10-15, 1.21 x 10-14 e 2.26 x 10-14 cm2 s-1 for V2O5, V2O5/PEI and V2O5/PEI/CNPs, respectively. Thus, the polymer and the CNPs provided new conducting pathways and connected isolated V2O5 chains in the host matrix. Therefore, novel spontaneous nanocomposites were formed, aiming to demonstrate the self-assembled method adopted for improving charge transport within host matrices.
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Oyedoh, Eghe Amenze. "Synthesis of controlled porosity resorcinol formaldehyde organic and carbon xerogels for adsorption applications." Thesis, Queen's University Belfast, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.602790.
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The synthesis of resorcinol formaldehyde xerogels was investigated by controlling its porosity for potential use as a precursor for activated carbon adsorbents for heavy metals removal from industrial wastewater. Resorcinol formaldehyde carbon xerogels were synthesised by sol-gel polymerization of resorcinol (R) with formaldehyde (F) in the presence of sodium carbonate (C) and then vacuum dried. Resorcinol formaldehyde (RF) gels were synthesised at same temperature conditions with varying resorcinol ! catalyst (R/C) and resorcinol/ water (R/W) ratios. The characterization of the resorcinol formaldehyde xerogels (RF), carbonized resorcinol formaldehyde xerogels (CRF) included: pore size distribution; surface area (BET); scanning electron microscopy (SEM!EDX); FTIR spectroscopy; and X-Ray diffraction (XRD). The ACRF was also analysed to determine its pHpzc , pHSolution , surface basicity and acidity. The resorcinol formaldehyde xerogels were carbonised and activated by physical activation with carbon dioxide. The surface areas of the carbonized resorcinol formaldehyde xerogels (CRF) and activated carbon resorcinol formaldehyde xerogels (ACRF) are 577.3 m2/g and 993.5 m2!g respectively. The increase in surface area is as a result of the development of microporosity with activation. In comparison the surface area of a commercial activated carbon (AC) obtained from Norit was found to be 884.4 m2/g. The adsorption of chromium metal ion in aqueous solutions by activated carbon resorcinol formaldehyde xerogels (ACRF) was investigated. The experimental data show that pore structure, surface area and the adsorbent surface chemistry are important factors that control the adsorption of metal ions. Equilibrium adsorption isotherms were analysed using the Langmuir, Freundlich and Sips models. Pseudo first order, pseudo second order, Elovich and intraparticle diffusion
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Aquino, Aline Scaramuzza. "Imobiliza??o de l?quidos i?nicos formados pelo c?tion 1-metil-3-(3-trimetoxissililpropil) imidaz?lio em MCM-41 por ancoragem e em xerogel para uso em captura e convers?o de CO2." Pontif?cia Universidade Cat?lica do Rio Grande do Sul, 2014. http://tede2.pucrs.br/tede2/handle/tede/3266.
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Previous issue date: 2014-07-30The study to new materials for CO2 capture indicates as an option, the use of ionic liquids as solvents for absorption, because they are compounds in which CO2 has a preferential solubility. Ionic liquids immobilized in mesoporous materials may present an advantageous combination in selective capture. Thus, the objective of the doctoral thesis is to synthesize and characterize structures of ionic liquids supported on mesoporous materials, checking the capacity of CO2 adsorption on these materials and the application of these materials as heterogeneous catalysts in the synthesis of propylene carbonate via cycloaddition with CO2. Ionics liquids were formed by the cation 1-methyl-3-(3-trimethoxysylilpropyl) imidazolium and supported with differents concentrations of IL via grafting in mesoporous material type MCM-41 and sol-gel process, change of the anion was performed only after the immobilization [Cl]- to [BF4]-, [PF6]- and [Tf2N]-. The characterization of materials was performed by infrared spectroscopy, solid state NMR, thermal analysis (TGA), scanning electronic microscopy, X-ray diffraction (DRX) and N2 adsorption. Lastly, assessment of CO2 adsorption was done through microbalance thermogravimetric (PTGA) trials. Results of the CO2 adsorption from the IL immobilized on MCM-41, shows that LICLM50 has the better adsorbent ability, 0.11 g CO2/ g adsorbent, and xerogel, LICLX20 gave 0.35 g CO2/ g adsorbent at 10 bar. As for the use in heterogeneous catalysis with supported ILs, maximum conversion obtained was 67 % with 82 % of selectivity for LICLM50. These materials have shown good ability to adsorb CO2 and, when used as catalysts for conversion of CO2 in cycloaddition reactions, they are well behaved and therefore favorable to employment in catalysis.
O estudo de novos materiais para a captura de CO2 aponta como uma op??o, o uso de l?quidos i?nicos como solventes para absor??o, pois s?o compostos nos quais o CO2 apresenta uma solubilidade preferencial. Imobilizar l?quidos i?nicos em materiais mesoporosos pode ser uma combina??o mais vantajosa na captura seletiva. Desta maneira, o objetivo desta tese de doutorado consiste em sintetizar e caracterizar estruturas de l?quidos i?nicos suportados em materiais mesoporosos, verificar a capacidade de adsor??o de CO2 nestes materiais, bem como aplicar estes materiais como catalisadores heterog?neos na s?ntese de carbonato de propileno via cicloadi??o com CO2. Os l?quidos i?nicos foram formados pelo c?tion 1-metil-3-(3-trimetoxissililpropil) imidaz?lio e suportados com concentra??es diferentes de LI via ancoragem em material mesoporoso tipo MCM-41 e via sol-gel, somente ap?s a imobiliza??o foi realizada a troca do ?nion [Cl]- para [BF4]-, [PF6]- e [Tf2N]-. A caracteriza??o dos materiais foi feita por t?cnicas de FTIR, RMN de estado s?lido, an?lises t?rmicas (TGA), microscopia eletr?nica de varredura, difra??o de raios-X (DRX) e adsor??o de N2 (BET). Por ?ltimo, foi feita a avalia??o quanto ? adsor??o de CO2 atrav?s de ensaios em microbalan?a termogravim?trica (PTGA). Os resultados de adsor??o de CO2 entre os imobilizados em MCM-41, LICLM50 apresenta melhor capacidade 0,11 g CO2/g adsorvente e, em xerogel, LICLX20 0,35 g CO2/g adsorvente, a 10 bar. Quanto ao uso em cat?lise heterog?nea com LIs suportados a convers?o m?xima obtida foi de 67 % e a seletividade de 82 % com LICLM50. Estes materiais apresentaram boa capacidade em adsorver o CO2 e, quando utilizados como catalisadores em rea??es de cicloadi??o para convers?o do CO2, tamb?m se portaram favor?veis ao emprego em cat?lise.
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Aquino, Aline Scaramuzza. "Imobilização de líquidos iônicos formados pelo cátion 1-metil-3-(3-trimetoxissililpropil) imidazólio em MCM-41 por ancoragem e em xerogel para uso em captura e conversão de CO2." Doctoral thesis, Pontifícia Universidade Católica do Rio Grande do Sul, 2014. http://hdl.handle.net/10362/15981.
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Previous issue date: 2014The study to new materials for CO2 capture indicates as an option, the use of ionic liquids as solvents for absorption, because they are compounds in which CO2 has a preferential solubility. Ionic liquids immobilized in mesoporous materials may present an advantageous combination in selective capture. Thus, the objective of the doctoral thesis is to synthesize and characterize structures of ionic liquids supported on mesoporous materials, checking the capacity of CO2 adsorption on these materials and the application of these materials as heterogeneous catalysts in the synthesis of propylene carbonate via cycloaddition with CO2. Ionics liquids were formed by the cation 1-methyl-3-(3-trimethoxysylilpropyl) imidazolium and supported with differents concentrations of IL via grafting in mesoporous material type MCM-41 and sol-gel process, change of the anion was performed only after the immobilization [Cl]- to [BF4]-, [PF6]- and [Tf2N]-. The characterization of materials was performed by infrared spectroscopy, solid state NMR, thermal analysis (TGA), scanning electronic microscopy, X-ray diffraction (DRX) and N2 adsorption. Lastly, assessment of CO2 adsorption was done through microbalance thermogravimetric (PTGA) trials.Results of the CO2 adsorption from the IL immobilized on MCM-41, shows that LICLM50 has the better adsorbent ability, 0. 11 g CO2/ g adsorbent, and xerogel, LICLX20 gave 0. 35 g CO2/ g adsorbent at 10 bar. As for the use in heterogeneous catalysis with supported ILs, maximum conversion obtained was 67 % with 82 % of selectivity for LICLM50. These materials have shown good ability to adsorb CO2 and, when used as catalysts for conversion of CO2 in cycloaddition reactions, they are well behaved and therefore favorable to employment in catalysis.
O estudo de novos materiais para a captura de CO2 aponta como uma opção, o uso de líquidos iônicos como solventes para absorção, pois são compostos nos quais o CO2 apresenta uma solubilidade preferencial. Imobilizar líquidos iônicos em materiais mesoporosos pode ser uma combinação mais vantajosa na captura seletiva. Desta maneira, o objetivo desta tese de doutorado consiste em sintetizar e caracterizar estruturas de líquidos iônicos suportados em materiais mesoporosos, verificar a capacidade de adsorção de CO2 nestes materiais, bem como aplicar estes materiais como catalisadores heterogêneos na síntese de carbonato de propileno via cicloadição com CO2. Os líquidos iônicos foram formados pelo cátion 1-metil-3-(3-trimetoxissililpropil) imidazólio e suportados com concentrações diferentes de LI via ancoragem em material mesoporoso tipo MCM-41 e via sol-gel, somente após a imobilização foi realizada a troca do ânion [Cl]- para [BF4]-, [PF6]- e [Tf2N]-. A caracterização dos materiais foi feita por técnicas de FTIR, RMN de estado sólido, análises térmicas (TGA), microscopia eletrônica de varredura, difração de raios-X (DRX) e adsorção de N2 (BET).Por último, foi feita a avaliação quanto à adsorção de CO2 através de ensaios em microbalança termogravimétrica (PTGA). Os resultados de adsorção de CO2 entre os imobilizados em MCM-41, LICLM50 apresenta melhor capacidade 0,11 g CO2/g adsorvente e, em xerogel, LICLX20 0,35 g CO2/g adsorvente, a 10 bar. Quanto ao uso em catálise heterogênea com LIs suportados a conversão máxima obtida foi de 67 % e a seletividade de 82 % com LICLM50. Estes materiais apresentaram boa capacidade em adsorver o CO2 e, quando utilizados como catalisadores em reações de cicloadição para conversão do CO2, também se portaram favoráveis ao emprego em catálise.
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Aquino, Aline Scaramuzza. "Imobilização de líquidos iônicos formados pelo cátion 1-metil-3-(3-trimetoxissililpropil) imidazólio em MCM-41 por ancoragem e em xerogel para uso em captura e conversão de CO2." Pontifícia Universidade Católica do Rio Grande do Sul, 2014. http://hdl.handle.net/10923/6826.
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Previous issue date: 2014The study to new materials for CO2 capture indicates as an option, the use of ionic liquids as solvents for absorption, because they are compounds in which CO2 has a preferential solubility. Ionic liquids immobilized in mesoporous materials may present an advantageous combination in selective capture. Thus, the objective of the doctoral thesis is to synthesize and characterize structures of ionic liquids supported on mesoporous materials, checking the capacity of CO2 adsorption on these materials and the application of these materials as heterogeneous catalysts in the synthesis of propylene carbonate via cycloaddition with CO2. Ionics liquids were formed by the cation 1-methyl-3-(3-trimethoxysylilpropyl) imidazolium and supported with differents concentrations of IL via grafting in mesoporous material type MCM-41 and sol-gel process, change of the anion was performed only after the immobilization [Cl]- to [BF4]-, [PF6]- and [Tf2N]-. The characterization of materials was performed by infrared spectroscopy, solid state NMR, thermal analysis (TGA), scanning electronic microscopy, X-ray diffraction (DRX) and N2 adsorption. Lastly, assessment of CO2 adsorption was done through microbalance thermogravimetric (PTGA) trials.Results of the CO2 adsorption from the IL immobilized on MCM-41, shows that LICLM50 has the better adsorbent ability, 0. 11 g CO2/ g adsorbent, and xerogel, LICLX20 gave 0. 35 g CO2/ g adsorbent at 10 bar. As for the use in heterogeneous catalysis with supported ILs, maximum conversion obtained was 67 % with 82 % of selectivity for LICLM50. These materials have shown good ability to adsorb CO2 and, when used as catalysts for conversion of CO2 in cycloaddition reactions, they are well behaved and therefore favorable to employment in catalysis.
O estudo de novos materiais para a captura de CO2 aponta como uma opção, o uso de líquidos iônicos como solventes para absorção, pois são compostos nos quais o CO2 apresenta uma solubilidade preferencial. Imobilizar líquidos iônicos em materiais mesoporosos pode ser uma combinação mais vantajosa na captura seletiva. Desta maneira, o objetivo desta tese de doutorado consiste em sintetizar e caracterizar estruturas de líquidos iônicos suportados em materiais mesoporosos, verificar a capacidade de adsorção de CO2 nestes materiais, bem como aplicar estes materiais como catalisadores heterogêneos na síntese de carbonato de propileno via cicloadição com CO2. Os líquidos iônicos foram formados pelo cátion 1-metil-3-(3-trimetoxissililpropil) imidazólio e suportados com concentrações diferentes de LI via ancoragem em material mesoporoso tipo MCM-41 e via sol-gel, somente após a imobilização foi realizada a troca do ânion [Cl]- para [BF4]-, [PF6]- e [Tf2N]-. A caracterização dos materiais foi feita por técnicas de FTIR, RMN de estado sólido, análises térmicas (TGA), microscopia eletrônica de varredura, difração de raios-X (DRX) e adsorção de N2 (BET).Por último, foi feita a avaliação quanto à adsorção de CO2 através de ensaios em microbalança termogravimétrica (PTGA). Os resultados de adsorção de CO2 entre os imobilizados em MCM-41, LICLM50 apresenta melhor capacidade 0,11 g CO2/g adsorvente e, em xerogel, LICLX20 0,35 g CO2/g adsorvente, a 10 bar. Quanto ao uso em catálise heterogênea com LIs suportados a conversão máxima obtida foi de 67 % e a seletividade de 82 % com LICLM50. Estes materiais apresentaram boa capacidade em adsorver o CO2 e, quando utilizados como catalisadores em reações de cicloadição para conversão do CO2, também se portaram favoráveis ao emprego em catálise.
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Guazzagaloppa, Jérémy. "Matériaux super-isolants thermiques à propriétés thermoélectriques intégrées." Thesis, Montpellier, 2019. http://www.theses.fr/2019MONTS086.
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Dans le cadre du développement de nouvelles sources d’énergie durables, la récupération d'énergie est essentielle. La plupart des processus industriels entraînent une perte colossale de chaleur, la thermoélectricité a donc pleinement son rôle à jouer dans ce développement grâce à l'effet Seebeck qui consiste à convertir un gradient de température en énergie électrique. Un bon matériau thermoélectrique nécessite une conductivité électrique σ élevée, un grand coefficient Seebeck α ainsi qu'une conductivité thermique λ faible. Cependant, malgré de récentes avancées dans le domaine, l’utilisation en masse des matériaux thermoélectriques usuels devient difficile du fait de leur toxicité, leur faible abondance et leur coût. Le développement de nouveaux matériaux en respect des contraintes environnementales devient alors nécessaire. Ainsi, avec l’émergence d’une nouvelle famille de matériaux, à savoir les matériaux organiques thermoélectriques, à base de polymères conducteurs et de gels (aérogels/xérogels), de nouvelles perspectives sont envisageables. A l’instar de ces nouvelles avancées, le but de ce travail est de fonctionnaliser des matériaux super-isolants thermiques possédant une très faible conductivité thermique en leur conférant des propriétés thermoélectriques. Cela a d’abord été réalisé par des simulations numériques basées sur la théorie de la fonctionnelle de la densité (DFT), ainsi que sur la dynamique moléculaire classique (DM), via différents modules appartenant au logiciel Materials Studio. Cela a permis de représenter numériquement et valider la structure de notre matériau, le xérogel de Résorcinol/Formaldéhyde. Une étude de dopage avec 5 % en particules de fer a ensuite été réalisée en DM afin d’étudier la dispersion des charges au sein du réseau RF et représenter le numériquement le matériau dopé en vue d’une future étude de ses propriétés thermoélectriques.Dans un second temps, l’objectif a été de définir le protocole de synthèse optimal en fonction des différents paramètres de synthèse et des différentes charges conductrices utilisées. L’étude de l’influence d’un traitement thermique par pyrolyse a alors permis l’amélioration de la conductivité électrique du matériau pur présentant un facteur de mérite ZT=2.7×〖10〗^(-16), (ZT=α^2 σT/λ permet de quantifier le rendement de la conversion thermoélectrique). Des dopages ont par la suite été effectués durant l’étape de gélification suivant différents taux de charge en vue d’atteindre un seuil de percolation. Un facteur de mérite ZT=2.4×〖10〗^(-3) a alors été obtenu avec un taux de dopage de 60 % en oxyde de graphène (GO). Cependant, ce type de dopant engendre un coût de synthèse trop important, nous nous sommes alors orientés vers d’autres types de charges, à savoir des fibres conductrices. Ceci a permis d’obtenir un ZT= 8.0×〖10〗^(-4) avec un taux de dopage de 10 % en fibres de polyacrylonitrile oxydée (PANOX). L’assemblage du module ainsi que la réalisation d’un banc d’essais ont par la suite permis de caractériser la performance thermoélectrique de nos différents matériaux. Une densité de puissance de l’ordre de 2 mW.m-2 a alors été obtenue avec le xérogel RF fibré PANOX d’une épaisseur de 1 cm et d’une surface de 50 cm² pour une différence de température de 30°C. Ce matériau a alors permis d’identifier une application dans le cadre de l’isolation thermique d’une batterie de véhicule hybride en vue de détecter une défaillance associée à la perte du vide. Finalement une étude se basant sur des modèles théoriques a démontré l’intérêt de poursuivre les recherches dans le but d’améliorer les propriétés thermoélectriques. Nous avons alors envisagé l’assemblage de modules composés de 1000 jonctions (p-p) puis (n-p) avec des matériaux cibles afin d’atteindre des niveaux de densité de puissance de plusieurs W.m-2 et des tensions de sortie de plusieurs V permettant de produire suffisamment d’énergie pour l’alimentation d’auxiliaires tels que des capteurs par exempleIn the search of new sustainable energies, the issue of energy harvesting is essential. Heat loss is involved in most of the industrial processes, thus thermoelectricity has its full role to play in this search through the Seebeck effect which consists in converting a temperature gradient into an electrical current. A good thermoelectric material requires a high electrical conductivity σ and Seebeck coefficient α and a low thermal conductivity λ. However, despite recent advances in the field, the use of conventional thermoelectric materials on a large scale becomes difficult due to their toxicity, low abundance and high cost. The development of new materials that respect environmental considerations has thus become necessary. Hence, with the emergence of a new family of materials, namely organic thermoelectric materials, based on conductive polymers and gels (aerogels/xerogels), new perspectives are now possible. In the frame of these new advances, the aim of this work is to functionalize thermal super-insulating materials with a very low thermal conductivity by adding thermoelectric properties. This was first done by numerical simulations based on density functional theory (DFT) and classical molecular dynamics (MD), via different modules included in the Materials Studio software. This allowed us to numerically represent and validate the structure of our thermal insulating material, the Resorcinol/Formaldehyde (RF) xerogel. A doping process with 5 % in iron particles was then performed using MD calculations in order to evaluate the dispersion of the charges within the RF network and to represent numerically the doped material for a future study of its thermoelectric properties via a Boltzmann formalism.In a second step, the objective was to identify the optimal synthesis protocol as a function of the different synthesis parameters and the different conductive dopants. The study of the influence of a thermal treatment by pyrolysis then allowed the improvement of the electrical conductivity of the pure material having a very low figure of merit ZT=2.7×〖10〗^(-16), (ZT=α^2 σT/λ is a measure of the efficiency of the thermoelectric conversion). A study of doping was then carried out during the gelling process according to different loading rates in order to reach a percolation threshold. A figure of merit ZT=2.4×〖10〗^(-3) was then obtained with a doping level of 60 % in graphene oxide (GO). However, this type of dopant generates a very high synthesis cost, which explain why we investigated other types of charges, namely electrically conductive fibers. In that case, we obtained a ZT= 8.0×〖10〗^(-4) with a doping level of 10 % in oxidized polyacrylonitrile fibers (PANOX). The assembly of the module and the realization of a test bench have made it possible to characterize the thermoelectric performance of our different materials. A power density of the order of 2 mW.m-2 was then obtained with the PANOX fiber-reinforced RF xerogel with a thickness of 1 cm and an surface area of 50 cm² for a temperature difference of 30°C. Thanks to this materials, we have identified an application as part of the thermal insulation of a hybrid vehicle battery in order to detect a failure associated with a vacuum loss. Finally, a study based on theoretical models has shown the interest of continuing research activities in order to improve the thermoelectric properties. We then considered the assembly of modules composed of 1000 junctions (pp) then (np) with target materials in order to reach higher power density levels of several W.m-2 and output voltages of several V to produce enough energy for the supply of auxiliaries such as sensors for example
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Amaral-Labat, Gisèle. "Gels poreux biosourcés : production, caractérisation et applications." Thesis, Université de Lorraine, 2013. http://www.theses.fr/2013LORR0081/document.
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Ce travail de recherche présente la préparation et la caractérisation de matériaux monolithiques hautement poreux dérivés majoritairement de ressources naturelles. L'objectif était de préparer de nouveaux gels biosourcés jusqu'à 91%, de proposer des alternatives au séchage supercritique au CO2, et d'étudier quelques propriétés d'intérêt de tels gels après séchage, non seulement à l'état organique mais, dans certains cas, après pyrolyse pour obtenir des gels de carbone. A ces fins, le tannin et le soja ont été testés comme précurseurs, à différentes concentrations et différents pH, et trois voies de séchages ont été utilisées : supercritique, lyophilisation et séchage évaporatif. Les gels obtenus ont été caractérisés en termes de densité, porosité, distributions de tailles de pores et surfaces spécifiques, qu'ils soient sous forme organique ou carbonée selon l'application envisagée ou le type de porosité attendue. Leurs propriétés mécaniques et thermiques ont aussi été mesurées. La très large gamme de textures poreuses obtenues a permis de proposer des applications en tant qu'isolants thermiques, supports de catalyseur, ou électrodes de condensateur électrochimiques, selon les casThis manuscript presents the preparation and the characterization of highly porous monolithic materials mainly derived from natural resources. The objectives were to: (i) develop new gels, biosourced up to the 91% level; (ii) suggest alternatives to supercritical drying in CO2, and (iii) investigate properties of interest for such gels in the organic state and, in some cases, after pyrolysis for obtaining carbon gels. For those purposes, tannin and soy flour were tested as precursors, at different concentrations and different pH, and three ways of drying were used: supercritical drying, freeze drying and evaporative drying. The obtained gels were characterized in terms of density, porosity, pore size distributions and specific surface area, whether in organic or in carbon form, depending on the intended application or expected type of porosity. Mechanical and thermal properties were also measured. The obtained broad range of porous textures allowed suggesting applications such as thermal insulators, catalyst supports or electrodes for electrochemical capacitors
Book chapters on the topic "Carbon xerogel"
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Xin, Qing, Yi Zhang, and Gaofeng Yan. "Adsorption of Microcystin-LR by Carbon Xerogel." In Lecture Notes in Electrical Engineering, 197–203. Berlin, Heidelberg: Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-25905-0_27.
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Landon, James, Xin Gao, Ayokunle Omosebi, and Kunlei Liu. "Structured and Surface-Modified Carbon Xerogel Electrodes for Capacitive Deionization." In Submicron Porous Materials, 1–23. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-53035-2_1.
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Maria Muresan, Liana, and Aglaia Raluca Deac. "Electrochemical Sensors/Biosensors Based on Carbon Aerogels/Xerogels." In Advances in Nanostructured Composites, 69–82. Boca Raton, FL : CRC Press, Taylor & Francis Group, [2018] | Series: Advances in nanostructured composites ; volume 2 | “A science publishers book.»: CRC Press, 2019. http://dx.doi.org/10.1201/9780429021718-4.
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Bratovcic, Amra, and Irena Petrinic. "Carbon Based Aerogels and Xerogels for Removing of Toxic Organic Compounds." In New Technologies, Development and Application III, 743–49. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-46817-0_84.
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Yang, Li Li, Jiu Peng Zhao, and Yao Li. "Microstructure and Mechanical Properties of Silica Xerogels Doped with SiC Whisker and Short Carbon Fiber." In Key Engineering Materials, 2104–6. Stafa: Trans Tech Publications Ltd., 2007. http://dx.doi.org/10.4028/0-87849-410-3.2104.
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Canal-Rodríguez, María, J. Angel Menéndez, and Ana Arenillas. "Carbon Xerogels: The Bespoke Nanoporous Carbons." In Porosity - Process, Technologies and Applications. InTech, 2018. http://dx.doi.org/10.5772/intechopen.71255.
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Job, Nathalie, Frédéric Maillard, Marian Chatenet, Cédric J. Gommes, Stéphanie Lambert, Sophie Hermans, John R. Regalbuto, and Jean-Paul Pirard. "Synthesis and characterization of highly loaded Pt/carbon xerogel catalysts prepared by the Strong Electrostatic Adsorption method." In Scientific Bases for the Preparation of Heterogeneous Catalysts - Proceedings of the 10th International Symposium, Louvain-la-Neuve, Belgium, July 11-15, 2010, 169–76. Elsevier, 2010. http://dx.doi.org/10.1016/s0167-2991(10)75021-7.
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G., Esther, J. Angel, and Ana Arenillas. "Designing Nanostructured Carbon Xerogels." In Nanomaterials. InTech, 2011. http://dx.doi.org/10.5772/17157.
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Job, Nathalie, Angélique Léonard, Jean-François Colomer, René Pirard, Benoît Heinrìchs, José Marien, Michel Crine, and Jean-Paul Pirard. "Metal catalysts supported on texture-tailored carbon xerogels." In Studies in Surface Science and Catalysis, 111–18. Elsevier, 2006. http://dx.doi.org/10.1016/s0167-2991(06)80897-9.
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Gheorghiu, Cristina C., María Pérez-Cadenas, M. Carmen Román-Martínez, Concepción Salinas-Martínez de Lecea, and Nathalie Job. "Immobilization of homogeneous catalysts in nanostructured carbon xerogels." In Scientific Bases for the Preparation of Heterogeneous Catalysts - Proceedings of the 10th International Symposium, Louvain-la-Neuve, Belgium, July 11-15, 2010, 647–51. Elsevier, 2010. http://dx.doi.org/10.1016/s0167-2991(10)75128-4.
Full textConference papers on the topic "Carbon xerogel"
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Veleva, Svetlana, Boryana Karamanova, and Antonia Stoyanova. "Activated carbon xerogel as an electrode material in supercapacitor systems." In RAD Conference. RAD Centre, 2023. http://dx.doi.org/10.21175/rad.abstr.book.2023.12.3.
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Toma, Shino, Xin Gao, Jesse Thompson, Keemia Abad, Saloni Bhatnagar, James Landon, and Kunlei Liu. "Decomposition of nitrosamines through electrochemically-mediated reduction on carbon xerogel electrodes." In ACS Spring 2019 National Meeting in Orlando, FL, March 31 – April 4, 2019. DIVISION: Division of Environmental Chemistry SESSION: Electrochemical Water Treatment SESSION TIME: 8:00 AM - 11:55 AM. US DOE, 2019. http://dx.doi.org/10.2172/1733231.
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