Lorsque les verres bioactifs entrent en contact avec des tissus vivants, une série de réactions physico-chimiques (dissolution, précipitation...) ont lieu à l’interface matériau / os, et conduisent à la formation d’une couche phosphocalcique, dont la composition est proche de la phase minérale de l’os (hydroxyapatite). La couche d’apatite sert de site de minéralisation pour les cellules osseuses, ce qui permet in fine un lien intime entre le verre bioactif et les tissus osseux. Ce lien est caractéristique de la bioactivité, qui peut être modulée via plusieurs paramètres du verre comme la composition en éléments majeurs et traces ou les propriétés texturales (surface spécifique, porosité).Dans ce contexte, nous avons élaboré des verres bioactifs dans des systèmes binaires (SiO2-CaO) et ternaires (SiO2-CaO-P2O5). Ces verres ont été dopés en ions zinc et magnésium via la voie sol-gel. Grâce à l'emploi de tensioactifs, nous avons obtenu des verres mésostructurés. Enfin, en utilisant des méthodes dites « d’opale inverse », des verres à macroporosité organisée ont été synthétisés. L'influence de ces paramètres sur la réactivité des verres au contact d’un milieu biologique (DMEM) a principalement été étudiée par des techniques utilisant des microfaisceaux d'ions. L'émission X induite par particules chargées (PIXE) combinée à la spectrométrie de rétrodiffusion Rutherford (RBS) a en effet démontré des effets évidents sur la cinétique, l'amplitude et la distribution spatiale des réactions physico-chimiques. / When bioactive glasses are in contact with living tissues, several physico-chemical reactions (dissolution, precipitation…) take place at the material / bone interface, and lead to the formation of a phosphocalcic layer, whose composition is close to the mineral phase of the bone (hydroxyapatite). The apatite layer is used as a mineralization site for bone cells and finally allows an intimate bond between the bioactive glass and osseous tissues. This bond is typical of bioactivity, which can be modulated through several parameters of the glass, like composition in major and trace elements or textural properties (specific surface, porosity).In this context, we elaborated bioactive glasses in binary (SiO2-CaO) and ternary (SiO2-CaO-P2O5) systems. Glasses have been doped with zinc and magnesium ions through the sol-gel route. Thanks to the use of surfactants, we obtained mesostructured glasses. Finally, by using inverse opal method, organized macroporous glasses have been synthesized. The influence of these parameters on the reactivity of glasses in contact with a biological medium (DMEM) has been mainly studied by techniques using micro-ion beams. The X-ray emission induced by charged particles (PIXE) combined with Rutherford backscattering spectrometry (RBS) has indeed demonstrated clear effects on the kinetics, the amplitude, and the spatial distribution of the physico-chemical reactions.

Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Nanopartículas de dióxido de titânio vêm sendo extensamente empregadas como fotocatalisa-dores, já que são eficientes na degradação de diversos poluentes. Visando a obtenção de titâ-nias com diferentes propriedades, realizaram-se sínteses através do método sol-gel, a partir da hidrólise do tetraisopropóxido de titânio (IV) TIPP e seguindo-se os princípios da Química Verde, dispensando-se temperaturas e pressões elevadas. Foi estudada a influência de dife-rentes parâmetros, como: pH, solvente, razão molar álcool/TIPP e ordem de adição dos rea-gentes. Foram obtidas titânias na forma cristalina anatásio, nanométricas, com elevadas áreas superficiais específicas e predominantemente mesoporosas. Visando-se obter titânias com melhores propriedades óticas, isto é, capazes de sofrer a fotoativação pela luz visível, foram sintetizadas titânias dopadas e co-dopadas com os metais ferro e rutênio (Fe3+ e Ru3+) e o a-metal N (N3). A síntese desses materiais também foi realizada através do método sol-gel, sendo a dopagem realizada durante o processo de hidrólise. As amostras foram caracterizadas na forma de pó por difração de raios-X, adsorção-dessorção de nitrogênio, microscopia ele-trônica de varredura e espectroscopia de refletância difusa no UV-Visível. A titânia pura a-presentou como única fase cristalina o anatásio, quando calcinada até 400 C, com a presença de traços de brookita. A partir de 600 C, observou-se o aparecimento da fase rutilo, que em 900C foi a única fase encontrada na titânia. A dopagem com Ru3+dificultou a transformação de fase anatásio para rutilo, ao contrário da dopagem com Fe3+. O processo de co-dopagem acelerou a formação de rutilo, que se apresentou como única fase nas amostras calcinadas a 600 C. As titânias dopadas apresentaram uma leve diminuição na energia de bandgap, sendo os dopantes capazes de deslocar a absorção para o vermelho. Foram realizados testes fotoca-talíticos visando à degradação do azocorante Reactive Yellow 145 com lâmpada de vapor de mercúrio de 125 W a fim de se comparar as atividades fotocatalíticas das titânias puras, dopa-das e co-dopadas, calcinadas a 300C. De todas as titânias sintetizadas, a titânia pura foi a que melhor degradou o corante, tendo um desempenho semelhante ao do TiO2 P25, da Evo-nik / Titanium dioxide nanoparticles have been widely used as photocatalysts due to their efficien-cy in degrading a variety of pollutants. Aiming at obtaining titanium dioxides with different properties, several syntheses were performed using the sol-gel method, hydrolyzing titanium tetraisopropoxide (IV) TIPP and adopting Green Chemistry principles, avoiding high temperatures and pressures. The effect of different synthesis parameters, such as: pH, sol-vent, alcohol/TIPP molar ratio, and reagents addition order was assessed. Nanometric, mesoporous (mainly), anatase titanium dioxides with high specific surface area were obtained. Aiing at developing titanium dioxides with improved optical properties, that is, capable of undergoing photoactivation by visible light, doped and co-doped titanium dioxides with the metals iron and ruthenium (Fe3+ and Ru3+) and the nonmetal N (N3) were synthesized. Those materials were also synthesized by the sol-gel method, in which doping was carried out during the hydrolysis step. Samples were characterized in powder form by X-ray diffraction, nitrogen adsorption-desorption, scanning electron microscopy, and diffuse reflectance spec-troscopy in the UV-Visible range. Pure titania samples presented anatase as the sole crystal-line phase when calcined at 400C, with traces amounts of brookite. At 600C, it was ob-served rutile phase, which is the only one at 900C. Doping with Ru3+ impaired the trans-formation of anatase to rutile, while just the opposite happened with Fe3+. The reagents order during the synthesis proved to be a very important parameter to be observed , since the surface area increases significantly and the amount of macropores in the final product. All doped titanium dioxides presented a slight decrease in the bandgap energy (red shift). Photocatalytic tests were performed aimed at degrading of the azo dye Reactive Yellow 145 with a 125 W mercury-vapor lamp. The performance of pure, doped, and co-doped titanium dioxides, calcined at 300C was compared. Pure titanium dioxide showed the best results, with a simi-lar formance to EvoniksTiO2 P25

Orientador: Prof. Dr. Mauro Coelho dos Santos / Dissertação (mestrado) - Universidade Federal do ABC. Programa de Pós-Graduação em Ciência e Tecnologia/Química, 2015. / Este trabalho apresenta a síntese e a caracterização de eletrocatalisadores binários e ternários suportados em carbono com paládio (PdSn/C, PdIr/C e PdSnIr/C) para oxidação do etanol em meio alcalino. Os materiais foram preparados pelo método sol-gel com 20% em massa dos metais e as proporções foram: para os binários de PdSn/C e PdIr/C 1:1, 2:1 e 3:1 (m/m); para os ternários de PdSnIr/C 1:1:1, 2:1:1 e 3:1:1 (m/m). Teve-se como objetivo definir quais apresentassem melhores resultados, possibilitando diminuir a quantidade do Pd, favorecendo a otimização da composição metálica para obter a melhor atividade eletrocatalítica para a oxidação do etanol. A caracterização física foi feita por medidas de difração de raios-X (DRX) e as análises indicaram principalmente a formação de óxidos dos metais. Por microscopia eletrônica de transmissão (MET) as partículas apresentaram tamanhos médios entre 5 e 9 nm e dispersão homogênea no suporte de carbono, com formação de alguns aglomerados. Experimentos de voltametria cíclica e cronoamperometria foram realizados para avaliar a atividade eletrocatalítica dos materiais. O eletrocatalisador binário PdIr/C 1:1 apresentou os melhores resultados pelas análises eletroquímicas quando comparado aos demais eletrocatalisadores binários e ternários produzidos. Sugere-se que este comportamento possa ser explicado pela oxidação de etanol com maior número efetivo de elétrons, pois formou-se principalmente, por análise em infra vermelho (IV), acetatos e acetaldeídos, vias favorecidas cineticamente, fato que pode ser atribuído à maximização da adsorção de etanol, ao mecanismo bifuncional e ao efeito eletrônico que também não pode ser descartado. Para os estudos conduzidos em célula a combustível, PdSn/C 3:1 apresentou melhores resultados, atribuídos a uma maior condutividade deste material, de acordo com o conteúdo de Pd. Do ponto de vista econômico e funcional, todos os eletrocatalisadores produzidos proporcionaram uma melhora no desempenho eletrocatalítico, quando comparados a Pd/C. / This work describes the synthesis and characterization of binary and ternary carbon supported electrocatalysts with palladium: (PdSn/C, PdIr/C e PdSnIr/C) for ethanol oxidation in alkaline medium. The materials were prepared by sol-gel method with 20% by weight of the metals and the proportions are, for binary PdSn/C e PdIr/C 1:1, 2:1 e 3:1 (w/w); for the ternary PdSnIr/C 1:1:1, 2:1:1 e 3:1:1 (w/w) in order to define which show the best results allowing a reduction in the amount of Pd, favoring the optimization of the metallic composition to obtain the best electrocatalytic activity for the oxidation of ethanol. The physical characterization was carried out by measurements of X-ray diffraction (XRD) and analysis indicated the formation of mainly metal oxides. By transmission electron microscopy (TEM) the particles had average sizes from 5 to 9 nm and homogeneous dispersion on carbon support, with formation of some clusters. Cyclic voltammetry and chronoamperometry experiments were conducted to evaluate the electrocatalytic activity of the material. Produced electrocatalysts had their activities compared, enabling the definition of the best material under study. The binary electrocatalyst PdIr/C 1:1 showed the best results, the electrochemical analysis when compared to other binary and ternary electrocatalysts produced, it is suggested that this behavior may be explained by the oxidation of ethanol with more effective electrons transferrence because formed mainly by analysis of infra-red (IR), acetates and acetaldehyde routes favored kinetically, which can be attributed to maximize the ethanol adsorption, the bifunctional mechanism and electronic effect cannot be ruled out. For studies conducted in fuel cell PdSn/C 3:1 showed better results what can suggest a higher conductivity of this material. From the economic and functional point of view all produced electrocatalysts provided an improved electrocatalytic performance, when comparing to Pd/C.

Made available in DSpace on 2014-06-11T19:25:32Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-11-27Bitstream added on 2014-06-13T20:53:34Z : No. of bitstreams: 1 ferreira_g_me_ilha.pdf: 556704 bytes, checksum: 2b9e9fd5741fa5b94b2deae1235c03eb (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Nas ultimas décadas, muitos dos trabalhos científicos estão relacionados à qualidade das águas naturais, como por exemplo, na identificação e quantificação de contaminantes orgânicos e inorgânicos. Dentre as espécies inorgânicas os metais potencialmente tóxicos são os mais estudados e, devido à baixa concentração em que algumas espécies são encontradas no ambiente, torna-se necessário a utilização de equipamentos sofisticados para sua quantificação segura. O uso de materiais como sílicas organofuncionalizadas para aplicação em extração em fase sólida (SPE) possibilita a pré-concentração desses íons e garante uma quantificação com maior segurança mesmo em equipamentos mais simples como espectrômetros de absorção atômica com atomização por chama. Neste contexto, o presente trabalho consistiu na síntese da sílica pelo método sol-gel, sua organofuncionalização com o ligante 4-amino-2-mercaptopirimidina (AMP), caracterização e aplicação do material na extração de íons Cu(II), Cd(II) e Pb(II) em meio aquoso. Os espectros de FTIR evidenciaram o ancoramento do ligante na sílica com a identificação de bandas em 1582 e 1541 cm-1 referente aos grupos NH e 3347 cm-1 referente aos grupos NH2 presentes na molécula do ligante. O ancoramento do ligante resultou no decréscimo das medidas de área superficial de 737 m2 g-1 para 399 m2.g-1, o qual esta relacionado a obstrução dos poros pelo ancoramento das moléculas orgânicas. Os espectros de RMN de 13C e 29Si confirmaram a presença ligações covalentemente entre a superfície da sílica e o grupo orgânico. Com os dados da análise elementar estimou-se uma quantidade de 3,619 10-4 mols do ligante por grama de SG-AMP. O sistema de pré-concentração foi otimizado utilizando o método univariado e os valores para a vazão da amostra e do eluente... / In the last decades, many scientific works are related to the quality of natural waters, such as the identification and quantification of organic and inorganic contaminants. Among the inorganic species potentially toxic metals are the most studied and, because of the low concentration of some species are found in the environment, it becomes necessary to use sophisticated equipment to secure its quantification. The use of materials such as silica organofuncionalized for application in solid phase extraction (SPE) allows preconcentration of these ions and provides quantification more safely even in the simplest equipment as atomic absorption spectrometers in flame module. In this context, this work was the synthesis of silica by sol-gel method, its organofuncionalization with the ligand 4-amine-2- mercaptopyrimidine (AMP), characterization and application of the material in the extraction of Cu (II), Cd (II ) and Pb (II) in aqueous means. The material was analyzed by FTIR showed the anchoring of the ligand on the silica by the identification of bands in 1582 and 1541 cm-1 on the NH groups and 3347 cm-1 on the NH2 groups present in the ligand molecule. The anchoring of the ligand resulted in the decrease of the measures of surface area of 737 m2 g-1 for 399 m2.g-1, which is related to clogged pores by anchoring of organic molecules. The NMR spectra of 13C and 29Si confirmed the presence of covalent bonds between the surface of silica and organic group. The data from elemental analysis to estimate an amount of 3.619 x 10-4 moles of ligand per gram of SG-AMP. The system of pre-concentration was optimized using the univariate method and the values for the flow of sample and eluent were set at 1.0 mL min-1, pH 5 to sample and nitric acid 2 mol L-1 as the eluent. The silica produced had a maximum adsorption of 0.0027, 0.0028 and 0.0018 mmol g-1 Cu (II), Cd (II) and Pb (II), respectively.

Le brillant est un attribut de l'apparence visuelle. Il s'agit d'une construction du système visuel, basée sur le signal optique en provenance d’une surface et capté par l'œil. Les développements récents en spectrophotométrie fondamentale ont produit des instruments à même de mesurer la réflexion lumineuse avec une acuité égale à celle du système visuel humain. Une description transverse, visuelle et optique, d'un même ensemble d'échantillons est maintenant possible. Dans ce travail, nous construisons via des procédés sol-gel une échelle de brillant métrologique multivariée en termes de topologie de surface, indice de réfraction, teinte et niveaux de brillant. Cette échelle est caractérisée par la suite en rugosité, en indice de brillant spéculaire et en BRDF. Nous présentons les techniques de mesure et les corrections employées sur ConDOR, notre goniospectrophotomètre dédié à la mesure haute résolution du pic spéculaire. Au terme de cette étude, l'instrument présente une résolution angulaire de 0,014°, la meilleure résolution atteinte à ce jour, deux fois inférieure à celle du système visuel humain. La dynamique est de 6,5 décades. ConDOR est employé pour mesurer les BRDF de plusieurs échantillons brillants issus de différentes échelles. Elles sont étudiées et les discutées. Un premier lien entre rugosité et BRDF est esquissé. Nous étudions finalement en nous basant sur une échelle de référence de brillant deux aspects de sa perception : l’effet d'un changement d'angle solide d'illumination et l’effet du réalisme de l'environnement d'observation. Nos résultats montrent que le système visuel est plus sensible aux variations de brillant dans des conditions d'observations réalistes, tant en matière d'éclairage que d'environnement. L’effet est particulièrement prononcé pour les échantillons mats. Les conditions moins réalistes ou moins naturelles peuvent mener les observateurs à la confusion. / Gloss is a visual appearance attribute. It is a construction from the visual system built on the optical signal from a surface and sensed by the eye. Recent developments in fundamental spectrophotometry lead to instruments able to measure luminous reflection with an acuity equal to the visual system in terms of angular resolution and dynamic. A cross-discipline description between optics and vision is now possible on a same set of samples. In this work, we build through sol-gel process a metrological gloss scale. It is multivariate in terms of surface topology, refractive indices, hue and gloss levels. This scale is then characterized in roughness, specular gloss and BRDF. We expose the measurement techniques and corrections used on our goniospectrophotomer ConDOR. This instrument is dedicated to high resolution measurement of specular peaks. By the end of this study, Condor has reached an angular resolution of 0.014°, the smaller achieved until now, twice better than the human visual system acuity. The dynamic range extends over 6.5 decades. ConDOR is used to measure BRDF of several glossy samples from different scales. These measurements are studied and discussed. A first link between roughness and BRDF is drawn.Using a reference gloss scale, we finally study two aspects of gloss perception: both effects of a change in the solid angle of illumination and in the observation environment realism. Our results indicate that the visual system is more sensitive to gloss variations under realistic conditions as well in lighting as in environment. This effect is particularly noticeable on matt samples. Lesser realistic or lesser natural conditions could lead observers to confusion.

Ce travail concerne l’étude de deux dispositifs coplanaires de type composite main droite/gauche (CRLH : composite right left handed). Il s’agit d’un résonateur d’ordre zéro (ZOR) et d’une ligne méta-matériaux (méta-ligne). Dans la première partie du mémoire, des généralités sur des méta-matériaux et des méta-lignes et quelques domaines d’applications sont présentés. Ensuite, des dispositifs agiles en fréquences de types composites CRLH sont décrites et en particuliers ceux à composites à bases de nanoparticules magnétiques réalisés dans ces travaux de thèse. L’agilité en fréquence recherchée a été obtenue avec moins de pertes dans les dispositifs. La deuxième partie concerne la caractérisation électromagnétique (EM) de sol-gel. Quelques méthodes de caractérisations EM sont présentées. Ensuite, celles qui ont été utilisées pour caractériser les composites solgel magnétiques. La troisième partie est vouée aux démarches technologiques et résultats expérimentaux sur les méthodes de caractérisation EM. Quelques procédés de dépôts ont été énumérés. Les propriétés EM complexes (ℰ* et μ*) de so-gel dopé ont été déterminées / This work concerns the study of two type coplanar devices composite right / left handed (CRLH). It is about a zero order resonator (ZOR) and a metamaterial line (meta-line). In the first part, brief generalities on metamaterials, meta-lines and some domain of application are presented. Then tunable devices in frequency CRLH composite types are described and particularly those made of magnetic nanoparticles (sol-gel) made in the this work. The desired frequency agility was achieved with less loss in the devices. The second part concerns the doped sol -gel electromagnetic characterization. Some methods for electromagnetic characterization are presented. Then, those which have been used to characterize the sol-gel are presented. The third part is devoted to technological approaches and experimental results on electromagnetic characterization methods. Some deposition processes have been listed. The electromagnetic complex properties (ℰ* et μ*)of magnetic so-gel were determined

A new class of multimetallic hierarchical aerogels composed entirely of interconnected Ni‐PdxPty nano‐building‐blocks with in situ engineered morphologies and compositions is demonstrated. The underlying mechanism of the galvanic shape‐engineering is elucidated in terms of nanowelding of intermediate nanoparticles. The hierarchical aerogels integrate two levels of porous structures, leading to improved electrocatalysis performance.

Une nouvelle approche de synthèse a été développée pour non seulement contrôler la morphologie, la taille et la texture de particules de silice mais aussi incorporer une ou plusieurs fonctionnalités à la surface interne de leurs pores. La morphologie sphérique, la monodispersité des particules, la porosité radiale, la dispersion et l'accessibilité des fonctionnalités ainsi que leur taux d'incorporation constituent les propriétés et les paramètres physico-chimiques privilégiés dans notre approche qui est basée sur la méthode de Stöber modifiée et la fonctionnalisation in-situ. Deux différentes applications ont été retenues pour étudier la quintessence de cette approche. La première consiste à incorporer des espèces métalliques (Al et Cu par exemple) dans les sphères de silice afin de les rendre fonctionnelles pour des applications catalytiques en phase liquide; et la deuxième consiste à greffer à la surface des particules des nanomachines sensibles permettant de contrôler le relargage des molécules actives pour des applications thérapeutiques. Dans les deux cas d'application, des performances optimales sont attendues. / A novel approach of synthesis has been developed in order to control simultaneously the morphology, size and textural parameters of silica particles, as well as to incorporate one or more functional groups in the pore walls. In this approach, based on the modified Stöber method and in-situ functionalization, emphasis is put on the spherical morphology, the particle monodispersity, the radially disposed porous structure, and the appropriate dispersion and accessibility of surface functional groups. Two potential applications have been selected so as to verify the feasibility of the approach. In view of materials use for heterogenous catalysis in the liquid phase, the monodisperses mesoporous silica spheres were derivatized with metallic species (e.g., Al and Cu) by direct incorporation in the synthesis stage. The second type of applications concerned the use of silica spheres as sensitive nanomachines for the controlled drug release and required grafting of appropriate organic molecules onto the silica surface.

Ce travail s’intéresse a la synthèse et à la caractérisation de revêtements hybrides O/I à base de silice, préparés par voie sol-gel et déposés sur polycarbonate (PC), pour des applications en milieu chaud et humide dans le domaine culinaire. Le PC étant connu pour sa sensibilité à l’hydrolyse dans ce type de milieux (provoquant sa dépolymérisation progressive et ainsi la libération de bisphénol A, molécule suspectée comme étant toxique), le rôle du revêtement est donc de protéger le PC et d’éviter son vieillissement prématuré, tout en améliorant ses propriétés mécaniques. Dans un premier temps, de nombreux sols ont été synthétisés et optimisés, principalement en termes de nature et quantités de précurseurs, et de pH, dans le but d’obtenir des revêtements homogènes et transparents. Un suivi des réactions d’hydrolyse et de condensation des sols a également été réalisé afin de déterminer le temps minimal de maturation de ces derniers. Apres dépôt des revêtements par dip-coating, les propriétés mécaniques des films ont été étudiées par de nombreuses techniques. D’un point de vue général, les propriétés des échantillons revêtus ont été trouvées supérieures à celles du PC nu. L’influence de nombreux paramètres de synthèse comme le ratio organoalcoxysilane(s)/silice colloïdale, l’ajout d’additifs, le type de traitement de surface du PC pré-dépôt ou encore les conditions de recuit, a également été étudiée. L’ensemble de ce travail a permis d’obtenir, à partir de deux systèmes sol-gel différents, des revêtements performants en termes de transparence, d’adhésion au substrat, de non-toxicité, couplés à des valeurs élevées de dureté, de densité et de module de Young / This work deals with the synthesis and the characterization of hybrid O/I silica coatings prepared by the sol-gel route and deposited on polycarbonate (PC), for applications in hot and humid environment in the alimentary field. PC is well-known for undergoing hydrolysis in such conditions (causing its progressive depolymerization and thus leading to the release of bisphenol A, a molecule suspected to be toxic): the function of the coating would thus consist in preventing PC from this kind of premature ageing, along with the enhancement of its mechanical properties. As a first step, a lot of different sols were synthesized and optimized, mainly in terms of type and quantity of precursors, along with the pH, in order to obtain transparent and homogeneous coatings. The hydrolysis and condensation reactions were monitored in order to determine the minimum ageing time to be waited before any film deposition. After deposition by dip-coating, the mechanical properties of the films were assessed by using many different techniques. Basically, the coated-PC samples display higher properties than the uncoated one. The influence of numerous synthesis parameters such as the organoalkoxysilanes/colloidal silica ratio, the presence of additives, the kind of surface treatment of PC before film deposition, or the annealing conditions was also studied. This whole work led to the synthesis, from two different sol-gel systems, of superior quality coatings in terms of transparency, adherence to the substrate, non-toxicity, along with elevated hardness, density and Young’s modulus values

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No. of bitstreams: 1 DissBGS.pdf: 2899470 bytes, checksum: a3a468cd5c6b79bbc4f8adf4720788bd (MD5) Previous issue date: 2014-03-28 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / The increasing use of fossil fuels in combustion enginees and power generation plants has caused a large increase in the emission of sulfur oxides, nitrogen oxides (NOx) and carbon monoxide into the atmosphere which creates serious environmental problems. Catalytic processes are used in the abatement of NOx and a promising alternative is the reduction of NOx using CO as reducing agent on catalysts containing supported transition metal oxides. Taking this into account, the aim of this study was to prepare catalysts based on Fe2O3, NiO or Fe2O3-NiO supported on ceria-zirconia (molar ratios Ce:Zr equal to 1:1 and 1:4), incorporating the metal precursor salt in the sun of the support (in situ addition). The results of XRD data, Rietveld refinement and TEM indicated the formation of a solid solution CeO2-ZrO2 with cubic structure fluorite type; furthermore, it was not observed diffraction peaks of intense X-ray of Fe or Ni oxide as a consequence of a proper distribution of these oxides in the supports. The addition of Fe2O3 and/or NiO led to a decrease of the average crystallite size, causing an increase in SBET of the catalysts compared to the pure support. N2 physisorption measurements showed that the catalysts showed significant mesoporosity, which was attributed to the addition of Tween 80 during the sol-gel preparation, moreover, RTPH2 results confirm that the Fe2O3 reduction occurs at lower temperatures in the presence NiO. In addition, the catalysts showed satisfactory performance in the reduction of NO to N2 with CO, suggesting that the sol-gel method is adequate in their preparation. Furthermore, the catalyst 0,90Fe - 1Ce:1Zr reached the highest values of CO conversion to CO2 and NO to N2 at lower temperatures. The Fe2O3 catalysts were more selective to N2 formation compared to those containing NiO. In conclusion, the conversion NO to N2 was significantly affected when in contact with O2 and H2O interferences; however, this conversion did not change significantly in the presence of SO2. The catalysts showed a more significant reduction in conversion of NO to N2 when evaluated in the simultaneous presence of O2, SO2 and H2O. / O crescente uso de combustíveis fósseis em motores de combustão e usinas de geração de energia vem causando um grande aumento na emissão de óxidos de enxofre, óxidos de nitrogênio (NOx) e monóxido de carbono na atmosfera, o que gera sérios problemas ambientais. No abatimento de NOx, em particular, utiliza-se processos catalíticos e uma alternativa promissora é a redução dos NOx utilizando CO como agente redutor sobre catalisadores à base de óxidos de metais de transição suportados. Nessa direção, a pesquisa teve por objetivo preparar catalisadores à base de Fe2O3, NiO ou Fe2O3-NiO suportados em céria-zircônia (proporções molares entre Ce e Zr iguais a 1:1 e 1:4), incorporando o sal precursor do metal no sol do suporte (adição in situ). Dados de DRX e MET indicaram a formação de uma solução sólida CeO2-ZrO2 com estrutura cúbica tipo fluorita, não se observando picos de difração de raios X intensos dos óxidos de Fe ou Ni, o que foi interpretado como uma consequência de uma adequada distribuição desses óxidos nos suportes. Os resultados do refinamento de Rietveld confirmaram os dados de DRX, indicando uma composição mássica baixa para os óxidos de Fe e/ou Ni. A adição de Fe2O3 e/ou NiO levou à uma diminuição do tamanho médio de cristalitos, causando um aumento na SBET dos catalisadores em relação ao suporte puro. Medidas de fisissorção de N2 mostraram que os catalisadores apresentaram mesoporosidade considerável, que foi atribuída à adição de Tween 80 durante a preparação sol-gel, além do mais, resultados de RTP-H2 corroboraram que a redução de Fe2O3 ocorre em temperaturas menores quando na presença de NiO. Os catalisadores apresentaram comportamento satisfatório na redução de NO a N2 com CO, indicando que o método sol-gel se mostrou adequado na sua preparação, sendo o sólido 0,90Fe - 1Ce:1Zr o que atingiu maiores valores de conversão de CO a CO2 e de NO a N2 em menores temperaturas. Em comparação aos catalisadores de NiO, os de Fe2O3 foram mais seletivos à formação de N2. Quando em contato com os interferentes O2 e H2O, a conversão NO a N2 foi consideravelmente afetada e na presença de SO2, essa conversão não se alterou significativamente. Quando avaliados na presença simultânea de O2, SO2 e H2O, os catalisadores apresentaram quedas de conversão de NO a N2 mais consideráveis.