<p>Nanotechnology has experienced a tremendous rise in the last decade. The synthesis of nanomaterials of defined structure and controlled properties is one of the most challenging part. Solution processing bottom-up fabrication techniques enables the facile synthesis of low dimension and ordered structures with low cost through the self-assembly of basic building blocks. Biotemplating has become an emerging field in which natural biomolecular objects are utilized for creating functional, hierarchical, controlled patterned structures with nanometric precision. It is a capital effective, eco-friendly and energy-efficient synthetic process. Viral biotemplating has shown great potential in electronics, environmental and biomedical devices. In recent years, in-planta produced Tobacco Mosaic Virus (TMV) and its variants have been used to produce metal nanorods and nanowires of monodisperse structures under mild conditions without the use of harsh chemical treatments although there remains much to be understood. Mass production of biotemplate, programming of viral particles of desired functionalities, manipulation for biomineralized metal materials of good quality have not been sufficiently studied to allow for directed synthesis. The fundamental studies on platform development for viral biotemplate production, design of viral proteins carrying engineered properties, and the hydrothermal synthesis of biotemplated metal nanomaterials, which create great uniformity and high coverage are of interest in this dissertation. Three experimental studies are outlined.<br></p><p><br></p><p>A novel virus biotemplate, Barley stripe mosaic virus (BSMV) virus-like particle is designed and engineered through genetic engineering. By fusing the Origin of Assembly from TMV to the transcript encoding BSMV capsid protein, the self-assembly of BSMV-VLP nanorod from microbial-based protein expression system was achieved for the first time. An alternate platform for viral particle production has been developed. Optimization of VLP expression, purification and processing conditions are performed. This developed alternative E. coli production platforms offer unique opportunities for genetic engineering and faster protein expression; therefore, the development of our system enables rapid design-build-test cycles for the engineering and production of BSMV-VLPs with desired properties. Results in this project shows the power of genetic engineering and serves as a springboard for genetic engineering of the VLPs.<br></p><p><br></p><p>Programming on BSMV-VLP is further used to decouple the VLP assembly into governing internal molecular interactions. To drive the nucleic acid free helical BSMV-VLP rod assembly and further increase the stability of capsid proteins, an identification of Caspar Carboxylate cluster in BSMV is performed. Various carboxylate residues were selected through protein crystal structure and examined systematically through experimental work. By introducing mutations on selected residues, the intersubunit carboxylate interaction of the proteins was significantly altered, resulting in an in vivo production of nucleic-acid free BSMV-VLP assembly for the first time. The change in interactions leads to increased stability of the modified VLP, enabling the formation of longer nanorods with lengths over one micrometer. Moreover, both wild-type and mutated BSMV-VLPs were shown to have great structural stability across a wide range of pHs. Overall, we exhibit experimental identification to systematically probe the key carboxylate interactions to increase the stability of proteins and drive RNA-free BSMV-VLP assembly. This project greatly expands the potential usefulness of the engineered BSMV-VLP biotemplates for a wide variety of applications.<br></p><p><br></p><p>Finally, to demonstrate the versatile uses of BSMV-VLP in biotemplating, the new biotemplate was utilized to expand understandings on the directed synthesis of metal nanostructures. By using the hydrothermal synthesis, VLPs were successfully utilized to synthesize monometallic palladium nanorods with a wide range of length scales. The VLP-mediated nanorods are more uniformly and fully-covered than the ones synthesized with in planta-produced BSMV virion. Besides, the synthesis shows an effective control over the metal nanorod diameter. The capability of BSMV-VLP was readily expanded from the synthesis of monometallic nanorods to bimetallic hybrid. In the absence of an exogenous reducing agent, mineralization of platinum, gold and copper was successfully demonstrated on the VLP. It is attributed to lower reduction barrier introduced by already-deposited palladium nanoparticles which serve as nucleation sites for subsequent metal reduction. The formation of bimetallic complexes was further supported by STEM, EDS and XPS analysis evidenced the presences of multiple metals. Overall, BSMV-VLP-mediated biotemplating using the hydrothermal synthesis has been confirmed to be a promising and feasible approach to create organic-inorganic complex nanocomposite.<br></p><p><br></p><p>Lastly, to move toward an application, the synthesized Pd nanorods coated with full coverage and great uniformity of nanoparticles were utilized as an exciting hydrogen sensing material. The developed hydrogen sensing system using a quartz crystal microbalance shows a fast response toward hydrogen as well as the ability of hydrogen detection and quantification of the adsorption capacity. This study serves as an entry point and opens up enormous possibility for next-generation of Pd-virus hybrid hydrogen sensors.<br></p><p><br></p><p>Taken together, this dissertation has demonstrated the engineering and production of a novel BSMV virus-like particle bacterial system. This alternative platform and developed parameter space for VLP production is genetically tractable and requires significantly shorter processing duration for large-scale and mass production. The BSMV-VLP biotemplated metal nanomaterials present great qualities and controllable dimensions. This approach has explored the synthetic palette and opened up enormous possibilities in the bottom-up nanofabrication of versatile and tunable organic-inorganic nanoscaled complex and would facilitate future engineering industrial applications.<br></p>

Indiana University-Purdue University Indianapolis (IUPUI) / With the exponential rise in manufacturing and usage of Li-ion batteries (LIBs) in the last decade, a huge quantity of spent LIBs is getting scrapped every year. Along with the efforts to making more capable and safer batteries over the last three decades, there is an immediate need for recycling these scrapped batteries. Most of these batteries typically use lithium manganese oxide (LMO), lithium cobalt oxide (LCO), lithium iron phosphate (LFP), and lithium nickel manganese cobalt oxide (NMC) cathode chemistries, and developing a technique towards regenerating these cathodes can ensure huge economic and environmental benefits for the present and future. This research focuses on a set of direct regeneration techniques with the goal of regenerating used cathode materials to be reused in LIBs. Used Apple iPad2 batteries with LCO chemistry and Nissan LEAF batteries with a combination of LMO-NMC chemistry are selected for this research. The scope of research can be divided into two parts as liberation/separation of cathode material and regeneration of liberated cathode. The liberation/separation process is carried out with the aid of ultrasonication and organic solvents with the objective being keeping the morphology and chemical composition intact for a better quality of the material. The regeneration process uses a hydrothermal technique with variations of parameters. 1:1 and 1:5 molar ratios between cathode material and a lithium lithiation agent are chosen to understand the effects of the molar ratio on cathode regeneration. In addition, the effects of processing solution (water vs. a solvent) are examined by replacing water with TEG. The effects of heat treatment on cathode regeneration are also investigated by observing phase changes of materials at different temperatures.

Cette thèse s’intéresse à la synthèse biosourcée de métallophosphates poreux pour trouver des solutions à l’épuisement des réserves naturelles de sources de phosphore qui servent habituellement à l’élaboration des réactifs inorganiques phosphorés (ex. H3PO4). Ceux-ci sont notamment utilisés pour la synthèse des métallophosphates poreux. Ces derniers possèdent des propriétés importantes dans les domaines de la catalyse, de l’adsorption et de la séparation. Toutefois il existe d’autres domaines peu étudiés tels que le biomédical et l’environnement où ces matériaux sont aussi utilisés. Au cours de cette thèse, la synthèse de zincophosphates et d’aluminophosphates poreux biosourcés a été réalisée à partir de différentes biomolécules (la caséine et les nucléotides) par la voie hydrothermale. Plusieurs paramètres de synthèse ont été étudiés (pH, température de synthèse, concentration des réactifs, influence des conditions de calcination ...). Les solides ont été caractérisés à l’aide de différentes techniques instrumentales (DRX, MEB, RMN31P, manométrie de N2, spectrofluorimétrie ...). Les propriétés antibactériennes et cytotoxiques des zincophosphates éventuellement enrichis en nanoparticules d’argent synthétisées à partir de caséine ont été évaluées sur la souche bactérienne Escherichia coli K 12 et des cellules ostéoprogénitrices STRO1A+ respectivement. Ces travaux situés à l’interface de la chimie des matériaux et de la biologie permettent d’envisager l’application des nouveaux métallophosphates synthétisés dans les domaines émergents du biomédical et de l’environnement. / This thesis work focuses on the biosourced synthesis of metal phosphates in order to find solutions to the depletion of the natural phosphorus resources that are usually used for the preparation of the phosphorus-containing inorganic reagents (i.e., H3PO4). Hydrothermal synthesis of metal phosphates involved them for example. Porous metal phosphates have important properties in catalysis, adsorption and separation fields. However, there are also less explored domains such as biomedical and environmental ones where they are further used. During this thesis, the synthesis of biosourced porous zinc phosphates and aluminum phosphates has been carried out using different biomolecules (casein and nucleotides) by hydrothermal method. Many synthesis parameters were studied (pH, synthesis temperature, reagents concentration, influence of calcination conditions ...). Solids were characterized using different techniques (XRD, SEM, 31P NMR, N2 adsorption, spectrofluorimetry ...). The antibacterial and cytotoxic properties of zinc phosphates optionally enriched in silver nanoparticles synthetized with casein were evaluated on the bacterial strain Escherichia coli K 12 and STRO1A+ osteoprogenitor cells respectively. This work at the interface of materials chemistry and biology makes possible to consider the application of the prepared new metal phosphates for emerging biomedical and environment fields.

Made available in DSpace on 2014-12-17T15:41:53Z (GMT). No. of bitstreams: 1 ViniciusPSC_DISSERT.pdf: 2657914 bytes, checksum: beb97c8aaf506ef6b97930de865d3dd2 (MD5) Previous issue date: 2011-02-25 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The catalytic processes play a vital role in the worldwide economy, a business that handles about US$ 13 billion per year because the value of products depends on the catalytic processes, including petroleum products, chemicals, pharmaceuticals, synthetic rubbers and plastics, among others. The zeolite ZSM-5 is used as catalyst for various reactions in the area petrochemical, petroleum refining and fine chemicals, especially the reactions of cracking, isomerization, alkylation, aromatization of olefins, among others. Many researchers have studied the hydrothermal synthesis of zeolite ZSM-5 free template and they obtained satisfactory results, so this study aims to evaluate the hydrothermal synthesis and the physicochemical properties of ZSM-5 with the presence and absence of template compared with commercial ZSM-5. The methods for hydrothermal synthesis of zeolite ZSM-5 are of scientific knowledge, providing the chemical composition required for the formation of zeolitic structure in the presence and absence of template. Samples of both zeolites ZSM-5 in protonic form were obtained by heat treatment and ion exchange, according to procedures reported in the literature. The sample of commercial ZSM-5 was acquired by the company Sentex Industrial Ltda. All samples were characterized by XRD, SEM, FTIR, TG / DTG / DSC, N2 adsorption and desorption and study of acidity by thermo-desorption of probe molecule (n-butylamine), in order to understand their physicochemical properties. The efficiency of the methods applied in this work and reported in the literature has been proved by well-defined structure of ZSM-5. According as the evaluation of physicochemical properties, zeolite ZSM-5 free template becomes promising for application in the refining processes or use as catalytic support, since its synthesis reduces environmental impacts and production costs / Os processos catal?ticos desempenham um papel vital na economia mundial, um neg?cio que movimenta aproximadamente US$13 bilh?es por ano, pois o valor dos produtos depende dos processos catal?ticos, incluindo os produtos petrol?feros, qu?micos, farmac?uticos, borrachas sint?ticas e pl?sticos, entre outros. A ze?lita ZSM-5 ? utilizada como catalisador em rea??es nas ?reas petroqu?mica, petrol?fera e qu?mica fina, destacando-se as rea??es de craqueamento, isomeriza??o, alquila??o, aromatiza??o de olefinas, entre outras. Muitos pesquisadores t?m estudado a s?ntese hidrot?rmica da ze?lita ZSM-5 ausente de direcionador org?nico estrutural e obtiveram resultados satisfat?rios, assim, este estudo visa avaliar a s?ntese hidrot?rmica e as propriedades f?sico-qu?micas da ZSM-5 com a presen?a e aus?ncia de direcionador org?nico estrutural, em compara??o com ZSM-5 comercial. Os m?todos para a s?ntese hidrot?rmica da ze?lita ZSM-5 s?o de conhecimento cient?fico, fornecendo a composi??o qu?mica necess?ria para a forma??o da estrutura zeol?tica em presen?a e aus?ncia de direcionador org?nico estrutural. As amostras de ambas as ze?litas ZSM-5 na forma prot?nica foram obtidas atrav?s de tratamentos t?rmicos e troca i?nica, de acordo com procedimentos relatados na literatura. A amostra de ZSM-5 comercial foi concedida pela empresa Sentex Industrial Ltda. Todas as amostras foram caracterizadas por DRX, MEV, FTIR, TG/DTG/DSC, Adsor??o e dessor??o de N2 e estudo da acidez por termodessor??o de mol?cula sonda (n-butilamina), a fim de compreender suas propriedades f?sico-qu?micas. A efici?ncia dos m?todos aplicados no presente trabalho e relatados na literatura foi comprovada pela estrutura bem definida da ze?lita ZSM-5. Conforme a avalia??o das propriedades f?sico-qu?micas, a ze?lita ZSM-5 ausente de direcionador org?nico torna-se promissora para aplica??o em processos de refino ou utiliza??o como suporte catal?tico, visto que, sua s?ntese reduz os impactos ambientais e custos de produ??o

Cette thèse s’inscrit dans une volonté de développer un procédé de synthèse de phyllominéraux de type talc en continu et en utilisant la technologie supercritique (plus spécifiquement utilisant l’eau comme solvant) afin d’avoir des temps de synthèses compatibles avec le milieu industriel (très courts) : une dizaine de secondes seulement. Cette voie innovante offre la possibilité d'obtenir un talc synthétique présentant des propriétés uniques telles qu’une haute pureté minéralogique et chimique, une grande surface spécifique(plusieurs centaines de m²/g) et un caractère hydrophile (gel de talc synthétique stable) qui a ainsi conduit à la formulation du premier minéral de talc liquide (son homologue naturel étant hydrophobe). De plus, il a été mis en place un procédé de séchage de ce minéral liquide par CO2 supercritique permettant l’obtention d’un solide de très haute surface spécifique et facilement réhydratable. Ce procédé a permis également la fonctionnalisation du talc synthétique élargissant ainsi les domaines d’applications de ce nouveau minéral liquide. La voie supercritique semble être la voie privilégiée pour un développement à l’échelle industrielle de la fabrication de particules minérales synthétiques (phyllosilicatées, silicatées et autres) en milieu aqueux. Une étude sur l’impact environnemental de ce nouveau procédé a été réalisée afin d’identifier les pistes d’optimisation possibles pour que cette voie soit la plus durable possible. / This thesis project was carried out to develop a continuous process for supercritical fluid synthesis of phyllominerals (especially using water as solvent) to fit synthesis time with industrial requirements: about ten seconds only. This innovative route provides synthetic talc with properties such as high mineralogical and chemical purity, large surface area (several hundred m²/g) and hydrophilic nature resulting in the formulation of the first liquid talc mineral (its natural counterpart being hydrophobic). Moreover, supercritical CO2 drying process implementation allows the obtention of very high specific surface area solid material easily rehydratable to prepare stable synthetic talc gel. This process allows synthetic talc functionalization, thus widening the fields of application for this new liquid mineral. Supercritical route appears as the optimal route to develop industrial scale mineral synthesis preparation (phyllosilicates, silicates and others). Environmental impact study of this new process further identifies possible optimization trails to make this route as sustainable as possible.

Les oxydes doubles lamellaires de cobalt et les oxydes de vanadium ont récemment suscité un vifintérêt suite à la découverte de leurs propriétés thermoélectriques prometteuses. Nos efforts visentà synthétiser de nouveaux composés dérivés de ces systèmes en utilisant la synthèse à l'étatsolide, l'échange d'ions et/ou les techniques hydrothermales. Afin de moduler et d'optimiser leurscaractéristiques thermoélectriques, nous avons ajusté la composition des oxydes de cobalt grâce àdes substitutions appropriées. Au sein du dioxyde de vanadium quasi-1D, nous avons considérétrois différentes structures polymorphes : M1, A et B. Nous avons exploré les différents systèmesen construisant l’ensemble des diagrammes de phases. Nous avons également étudié l'effet de lasubstitution du vanadium par le molybdène et le chrome sur la stabilité de ces structurespolymorphes et caractérisé leurs propriétés électroniques en relation avec les mécanismes detransition de phase. / Lamellar cobalt double oxides and vanadium oxides have recently attracted tremendous interestafter the discovery of their interesting thermoelectric properties. Our efforts aimed at synthesizingnovel related compounds using standard solid state, ion exchange and/or hydrothermaltechniques. In order to modulate and optimize their thermoelectric characteristics, we have tunedthe composition of cobalt double oxides by appropriate substitutions. In quasi 1D vanadiumoxides, the interplay between spin, charge and orbital degrees of freedom often leads toremarkable properties. Here we dealt with three different polymorphs of vanadium dioxide,namely M1, A and B. We explored the several novel systems by constructing systematic phasediagrams. We also studied the effect of Mo and Cr:V substitution on the stability of thesepolymorphs and characterized their electronic properties in relation with the structural phasetransition mechanisms. Finally, we explored their potentiality for thermoelectric applications.

Made available in DSpace on 2014-12-17T14:07:00Z (GMT). No. of bitstreams: 1 AuristelaCM_DISSERT.pdf: 1278248 bytes, checksum: cbdcf9cab5a2fc14113da4b21bc60b64 (MD5) Previous issue date: 2011-11-28 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The mesoporous molecular sieves of the MCM-41 and FeMCM-41 type are considered promissory as support for metals used as catalysts in oil-based materials refine processes and as adsorbents for environmental protection proposes. In this work MCM-41 and FeMCM41 were synthesized using rice husk ash - RHA as alternative to the conventional silica source. Hydrothermal synthesis was the method chosen to prepare the materials. Pre-defined synthesis parameters were 100?C for 168 hours, later the precursor was calcinated at 550?C for 2 hours under nitrogen and air flow. The sieves containing different proportions of iron were produced by two routes: introduction of iron salt direct synthesis; and a modification post synthesis consisting in iron salt 1 % and 5% impregnation in the material followed by thermal decomposition. The molecular sieves were characterized by X ray diffraction XRD, Fourier transform infrared spectroscopy FT-IR, X ray fluorescence spectroscopy XFR, scanning electronic microscopy SEM, specific surface area using the BET method, Termogravimetry TG. The kinetic model of Flynn Wall was used with the aim of determining the apparent activation energy of the surfactant remove (CTMABr) in the MCM- 41 porous. The analysis made possible the morphology characterization, identifying the presence of hexagonal structure typical for mesoporous materials, as well as observation of the MCM41 and iron of characteristic bands. / As peneiras moleculares mesoporosas do tipo MCM-41 e FeMCM-41, s?o consideradas promissoras como suporte para metais, usadas como catalisadores em processos de refino de materiais a base de petr?leo e como adsorventes com o prop?sito de prote??o ambiental. Neste trabalho MCM-41 e FeMCM-41 foram sintetizadas utilizando a cinza da casca de arroz CCA, como alternativa para a fonte de s?lica. O m?todo escolhido foi a s?ntese hidrotermal para o preparo dos materiais, a temperatura de 100 ?C por 168 horas em estufa, posteriormente foi calcinado a 550 ?C por 2 horas sob fluxo de nitrog?nio e ar. As peneiras moleculares contendo diferentes propor??es de ferro foram produzidas por duas rotas: introdu??o do sal de ferro no gel de s?ntese e impregna??o de 1% e 5% de ferro no MCM-41 sintetizado. As peneiras moleculares foram caracterizadas por difra??o de raios X DRX, espectroscopia no infravermelho por transformada de Fourier (Fourier transform infrared spectroscopy FT-IR), espectroscopia de fluoresc?ncia de raios X FRX, microscopia eletr?nica de varredura MEV, ?rea superficial espec?fica atrav?s do m?todo BET e Termogravimetria TG. O modelo cin?tico de Flynn Wall foi utilizado com o objetivo de determinar a energia de ativa??o aparente da remo??o do surfactante (CTMABr) nos poros do MCM-41. As an?lises possibilitaram a caracteriza??o morfol?gica, identificando a presen?a da estrutura hexagonal t?pica dos materiais mesoporosos, assim como das bandas caracter?sticas do MCM41 e do ferro.

Submitted by Maria Medeiros (maria.dilva1@ufcg.edu.br) on 2018-08-16T11:47:56Z No. of bitstreams: 1 FABIANA MEDEIROS DO NASCIMENTO SILVA - TESE (PPGEQ) 2017.pdf: 6622967 bytes, checksum: bfed827814b744a5e9e9e565d28f0682 (MD5) / Made available in DSpace on 2018-08-16T11:47:56Z (GMT). No. of bitstreams: 1 FABIANA MEDEIROS DO NASCIMENTO SILVA - TESE (PPGEQ) 2017.pdf: 6622967 bytes, checksum: bfed827814b744a5e9e9e565d28f0682 (MD5) Previous issue date: 2017 / Capes / O presente trabalho tem como objetivo geral sintetizar as membranas zeolíticas (Mordenita/α-alumina), utilizando os métodos de síntese hidrotérmica, crescimento secundário: dip-coating e transporte em fase vapor, para serem avaliadas no processo de separação emulsão óleo/água. Dentro deste contexto foram avaliados alguns parâmetros, destacando-se, a influência do tempo de cristalização na síntese da zeólita mordenita, a influência do precursor (sulfato de alumínio e gibsita) na síntese da membrana zeolítica, influência dos métodos de síntese das membranas zeolíticas e os testes de permeação de água e o processo de separação emulsão óleo/água. A síntese da zeólita mordenita foi realizada utilizando o método hidrotérmico a 170°C, com tempos de cristalização de 24, 36, 48, 72, 96 e 120 horas, a fim de avaliar a cristalinidade da zeólita, e selecionar o melhor tempo para a síntese das membranas zeolíticas. Os suportes cerâmicos α-alumina foram preparados a partir da decomposição dos precursores sulfato de alumínio a 1000°C e gibsita a 1200ºC por 2 horas, e conformados, compactados e sinterizados a 1300ºC por 2h, e então submetidos às técnicas de caracterização: Difratometria de raios X (DRX), Adsorção Física de Nitrogênio, Microscopia Eletrônica de Varredura (MEV), Espectroscopia de Fluorescência de raios X por Energia Dispersiva (FRX-ED) e Termogravimétrica/Térmica Diferencial (TG/DTA). As membranas zeolíticas foram sintetizadas pelos métodos de síntese hidrotérmica, crescimento secundário: dip-coating e transporte em fase vapor a 170°C por 72h e caracterizadas por DRX e MEV. Os suportes cerâmicos e as membranas zeolíticas foram avaliadas em testes de permeação de água e no sistema de separação emulsão óleo/água de um efluente sintético, utilizando um processo de separação por membrana (PSM). Os ensaios foram realizados nas condições de concentração inicial da emulsão 100 mg.L-1, temperatura de 25 °C e pressão de 2,5 bar, permitindo avaliar a permeabilidade e a seletividade a partir da variação da concentração do permeado em (mg.L-1) e da percentagem de rejeição ao óleo (%R). A partir dos resultados obtidos para a síntese dos materiais, pode-se observar a efetiva formação da zeólita mordenita em fase pura e cristalina. Os precursores foram decompostos de maneira satisfatória obtendo a fase α-alumina. A manutenção da fase α-alumina pós-produção dos suportes cerâmicos foi confirmada após caracterização. De acordo com os resultados exibidos pelas análises de DRX e MEV as membranas zeolíticas MZMOR/α-alumina apresentaram uma distribuição homogênea e uniforme dos cristais zeolíticos correspondentes à fase mordenita, sem a presença de impurezas, livres de defeitos e sem fissuras, confirmando a formação da estrutura da membrana zeolítica pelos três métodos de síntese, utilizados neste trabalho. A zeólita mordenita se mostrou excelente em relação à adesão e formação da camada zeolítica sobre o suporte cerâmico α-alumina. A partir da avaliação da permeabilidade e seletividade nos testes de separação da emulsão óleo/água, pode-se concluir que a inserção da zeólita mordenita aos suportes cerâmicos melhorou o processo de separação da emulsão óleo/água. Em termos de eficiência no processo de separação, considera-se que a membrana zeolítica MZMOR/α – Al2O3 (SHGB) foi a que apresentou melhor relação entre fluxo e capacidade seletiva, mostrando a eficácia da utilização das membranas zeolíticas. Todas as membranas zeolíticas sintetizadas e avaliadas mostraram-se promissoras. / The objective of the present work is to synthesize zeolite membranes (Mordenite/α-alumina) using hydrothermal synthesis, secondary growth: dip-coating and vapor-phase transport, to be evaluated in the oil/water emulsion separation process. The influence of the crystallization time on the synthesis of the mordenite zeolite, the influence of the precursor (aluminum sulphate and gibsite) on the synthesis of the zeolite membrane, influence of the synthesis methods of the zeolite membranes and the water permeation tests and the oil/water emulsion separation process. The synthesis of the mordenite zeolite was performed using the hydrothermal method at 170°C, with crystallization times of 24, 36, 48, 72, 96 and 120 hours, in order to evaluate the crystallinity of the zeolite, and to select the best time for the synthesis of zeolite membranes. The α-alumina ceramic supports were prepared from the decomposition of the aluminum sulfate precursors at 1000°C and gibsite at 1200°C for 2 hours, and conformed, compacted and sintered at 1300°C for 2h, and then submitted to the characterization techniques: (XRD), Nitrogen Physical Adsorption, Scanning Electron Microscopy (SEM), X-ray Fluorescence Spectroscopy (FRX-ED) and Thermogravimetric/Differential Thermal (TG/DTA). The zeolite membranes were synthesized by hydrothermal synthesis, secondary growth: dip-coating and vapor-phase transport at 170°C for 72 hours and characterized by XRD and SEM. Ceramic supports and zeolite membranes were evaluated in water permeation tests and in the oil/water emulsion separation system of a synthetic effluent using a membrane separation process. The tests were carried out under the conditions of initial concentration of the emulsion 100 mg.L-1, temperature of 25°C and pressure of 2,5 bar, allowing to evaluate the permeability and the selectivity from the variation of the permeate concentration in (mg. L-1) and the percentage of oil rejection (% R). From the results obtained for the synthesis of the materials, it is possible to observe the effective formation of zeolite mordenite in pure and crystalline phase. The precursors were satisfactorily decomposed to give the α-alumina phase. The maintenance of the post-production α-alumina phase of the ceramic supports was confirmed after characterization. The MZMOR/α-alumina zeolite membranes presented a homogeneous and uniform distribution of the zeolite crystals corresponding to the mordenite phase, without the presence of impurities, free of defects and without cracks, confirming the formation of the structure of the zeolite membrane by the three methods of synthesis, used in this work. The mordenite zeolite showed excellent adhesion and formation of the zeolitic layer on the ceramic support α-alumina. From the evaluation of the permeability and selectivity in the oil/water emulsion separation tests, it can be concluded that the insertion of the mordenite zeolite to the ceramic supports improved the separation process of the oil/water emulsion. In terms of efficiency in the separation process, the zeolite membrane MZMOR/α-Al2O3(SHGB) was considered to have the best relationship between flow and selectivity, showing the efficacy of zeolite membranes. All zeolite membranes synthesized and evaluated were promising.

Cette thèse est consacrée à l’élaboration de cellules photovoltaïques hybrides solides sensibilisées à colorant, composées d’une couche dense de germes de ZnO recouverte de nanobâtonnets de ZnO sensibilisés par un colorant et infiltrés par du spiro-OMeTAD. La couche dense de germes de ZnO a été optimisée, afin qu’elle soit compacte, homogène et bien orientée. Les nanobâtonnets sont synthétisés par voie hydrothermale. L’influence de différents paramètres de synthèse sur la morphologie des nanobâtonnets a été testée. Deux méthodes permettant de modifier l’écart entre les nanobâtonnets ont également été mises au point. Les performances des cellules photovoltaïques varient en fonction de la longueur des nanobâtonnets, du colorant utilisé, de la durée de vieillissement des cellules à l’air, l’atmosphère, la température… Enfin, nous avons réussi à obtenir un rendement dépassant 1%, ce qui est supérieur à la meilleure performance publiée actuellement (0,25%) pour le même type de dispositif. / This thesis deals with solid state dye sensitized solar cells in which dye sensitized ZnO nanorods are associated with spiro-OMeTAD (solid hole conductor). Nanorods are grown on the top of a dense ZnO seed layer. The growth of a dense, homogeneous and well oriented layer is achieved after optimization of the deposition procedure. ZnO nanorods are obtained after submitting the dense ZnO layer to an hydrothermal treatment. The nanorods morphology evolution with reactants concentration, reaction temperature and time,… was determined. The solar cells performances depend also on the nanorods length, the type of dye, the cell ageing time in air, the atmosphere and the cell temperature…The best performance published nowadays (0.25%) for our type of photovoltaic devices is really inferior to the 1% efficiency we obtained.

Les nanomatériaux représentent un créneau de recherche en plein essor dans de nombreuxdomaines. Leurs propriétés inédites leur confèrent de nombreux avantages mais soulèvent égalementdes interrogations quant à leur profil toxicologique. Parmi leurs applications possibles, lesnanomatériaux sont intégrés au sein de topiques protecteurs : dans le secteur militaire, afin de limiterla pénétration cutanée des agents chimiques de guerre et dans le secteur cosmétique, notammentdans les produits de protection solaire. Ce travail porte sur l'intérêt du dioxyde de cérium pur ou dopéau calcium dans ces deux applications. Dans un premier temps, les nanoparticules ont étésynthétisées par une méthode hydrothermale, assistée de la voie micro-ondes. La caractérisation pardifférentes méthodes a permis d'identifier la phase cristalline du CeO2 et a montré que lesnanoparticules présentaient une taille de 3 nm, pouvant être augmentée jusqu'à 95 nm en fonction dutraitement thermique appliqué. Par la suite, l'efficacité des nanoparticules seules puis incorporées ausein de topiques à effets barrières vis-à-vis de la pénétration du paraoxon, agent organophosphoré, aété testée. Une émulsion H/E constituée de 10 % de cérine a permis de réduire de façon significativela pénétration du toxique. Enfin, la photoprotection et la sécurité d'emploi du CeO2 ont été comparéesà celles des filtres solaires, et notamment à celles de l'oxyde de zinc (ZnO) fréquemment rencontrédans les produits de protection solaire. Le CeO2, en améliorant la protection dans le domaine des UVBet en ne présentant aucun effet antiprolifératif ou génotoxique sur une lignée cellulaire dekératinocytes humains, représente une alternative particulièrement intéressante au ZnO. / Nanomaterials represent a growing niche research in many fields. Their unusual properties provide many benefits, but also raise questions about their toxicological profile. Among their applications, nanomaterials are integrated into topical skin protectant: in the military sector, in order to reduce skin penetration of chemical warfare agents and in the cosmetics industry, especially in sunscreen products. This work focuses on the interest of pure or calcium doped cerium dioxide in these two applications. Initially, the nanoparticles were synthesized by a microwave-hydrothermal method. Characterization by different methods has identified the crystalline phase of CeO2 and has showed that the nanoparticles had a size of 3 nm, which could be increased up to 95 nm depending on the heat treatment applied. Thereafter, the effectiveness of nanoparticles alone and then incorporated in a topical barrier cream over the penetration of paraoxon, organophosphorus agent was tested. An O/W emulsion, consisting of 10 % ceria, has reduced significantly the penetration of the toxic. Finally, photoprotection and safety of CeO2 were compared with sunscreens, and in particular with zinc oxide (ZnO), frequently encountered in sunscreen products. CeO2, improving protection in the UVB range and showing no antiproliferative or genotoxic effect on human keratinocyte cell line, is a particularly attractive alternative to ZnO.