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<p>The pore-size dependence of liquid diffusivity in mesopores has been a controversial topic. It is especially meaningful in dye-sensitized solar cells (DSSCs) because the triiodide ion diffusivity is closely related to the cell performance. By applying electrochemical measurements, the pore-size dependence of ion diffusivity in DSSCs was investigated based on TiO₂ thin films of variable pore diameters. The alternation of pore-size was achieved by the epitaxial growth of TiO₂ after TiCl₄ post-treatments. From the trend of normalized diffusivities, the respective valid regimes of pore-size dependent and independent diffusion were determined, which were separated by the transition point located at 5-7 nm. In addition, my results have showed that the DSSC fabrication processes, e.g., dye loading, TiCl₄ post-treatment will not lead to the transition of diffusion behaviors. Furthermore, the unexpected drop of diffusivity after one TiCl₄ treatment is attributed to the involvement of surface diffusion in untreated TiO₂ matrix.</p> / Master of Applied Science (MASc)

Tesis por compendio / [EN] The doctoral thesis presented under the title "Hybrid inorganic-organic materials for the optical recognition of neutral and anionic species" has had as its main objective the synthesis and characterization of organic-inorganic hybrid materials based on the combination of the principles of Supramolecular Chemistry and Materials Science. Recent studies confirm that cooperation between these two areas of Chemistry allow the simulation of what natural living beings have been doing for millions of years in a natural way. At cellular level, many vital functions are related to the ability of a particular receptor to recognize a particular species, giving a specific answer. But what is more interesting is that in living organisms, most of these systems do not exist as dissolved molecules, but are bounded to a (bio)organic skeleton with more or less flexibility. When we imitated these systems bearing in mind the supramolecular and analytical chemistry, we find that we need a sensory molecule able to join with the specie that we want to detect and at the same time, this union must produce a change in its physico-chemical properties giving as a result a signal. But moreover, if we take advantatge of the fact that siliceous nanostructured materials present a high physical and chemical stability and that they have cavities where the sensor system can be incorporated into, we have the synthetic hybrid organic-inorganic combination similar to the natural one. In order to develop this idea, we have used sensor systems widely studied in molecular recognition processes in aqueous media and we have applied them to the inorganic-organic hydrid materials. Therefore, the present work thesis has been structured in two parts: on the one hand, the synthesis and characterization of the functionalized inorganic porous solid materials by the study and detection of amines using the "chemodosimeter" approach. On the other hand, we have made the synthesis and characterization of the organic functionalized inorganic porous solid materials for the study and detection of anionic species through the displacement assays approach. / [ES] La tesis doctoral que se presenta bajo el título "Hybrid inorganic-organic materials for the optical recognition of neutral and anionic species" ha tenido como objetivo principal la síntesis y caracterización de materiales híbridos orgánico-inorgànicos basados en la combinación de los principios de la Química Supramolecular y la Ciencia de los Materiales. Recientes estudios corroboran que la cooperación entre estas dos áreas de la Química permite simular lo que ya hace millones de años realizan de forma natural los organismos vivos. A nivel celular, muchas de las funciones vitales están relacionadas con la habilidad de un receptor concreto para reconocer una determinada especie, dando una respuesta específica. Pero lo que resulta más interesante, es que en los organismos vivos, la mayoría de estos sistemas no existen en forma de moléculas disueltas, sino que están unidos con mayor o menor flexibilidad a un esqueleto bio(in)orgánico. Cuando imitamos estos sistemas teniendo en cuenta la química supramolecular y analítica, nos encontramos que necesitamos de una molécula indicadora que sea capaz de unirse a la especie que queremos detectar y que a su vez, esta unión produzca un cambio en las propiedades físico-químicas de la entidad para producir una señal. Pero además, si aprovechamos el hecho de que los materiales silíceos nanoestructurados presentan una alta estabilidad física y química y que proporcionan cavidades donde alojar al sistema sensor, tenemos la combinación híbrida orgánico-inorgánico sintética similar a la natural. Con el objetivo de desarrollar esta idea, hemos utilizado sistemas sensores ampliamente estudiados en procedimientos de reconocimiento molecular en disolución acuosa y los hemos aplicado a los materiales híbridos orgánico-inorgànicos. De esta manera, el trabajo de tesis se ha estructurado en dos partes: por una parte, la síntesis y caracterización de materiales sólidos inorgánicos porosos funcionalizados para el estudio y detección de aminas utilizando el procedimiento de "dosímetro químico", y en una segunda parte, se ha llevado a cabo la síntesis y caracterización de sólidos inorgánicos porosos funcionalizados para el estudio y detección de especies aniónicas mediante el procedimiento de "ensayos por desplazamiento". / [CA] La tesis doctoral que es presenta sota el títol "Hybrid inorganic-organic materials for the optical recognition of neutral and anionic species" ha tingut com objectiu principal la síntesi i caracterització de materials híbrids orgànic-inorgànics basats en la combinació dels principis de la Química Supramolecular i la Ciència dels Materials. Estudis recents corroboren que la cooperació entre aquestes dues àrees de la Química permet simular el que ja fa milions d'anys realitzen de forma natural els organismes vius. A nivell cel·lular, moltes de les funcions vitals estan relacionades amb l'habilitat d'un receptor concret per a reconèixer una espècie determinada, donant una resposta específica. Però el que és més interessant, és que als organismes vius, la majoria d'aquests sistemes no existeixen en forma de molècules dissoltes, sinó que estan units amb major o menor flexibilitat a un esquelet bio(in)orgànic. Quan imitem aquests sistemes tenint en compte la química supramolecular i analítica, ens trobem que necessitem d'una molècula indicadora que sigui capaç d'unir-se a l'espècie que volem detectar i que alhora, aquesta unió produeixi un canvi en les propietats fisico-químiques de l'entitat per produir una senyal. Però a més, si aprofitem el fet que els materials silícics nanoestructurats presenten una alta estabilitat física i química i que proporcionen cavitats on es pot allotjar el sistema sensor, tenim la combinació híbrida orgànica-inorgànica sintètica semblant a la natural. Per tal de desenvolupar aquesta idea, hem utilitzat sistemes sensors ampliament estudiats en procediments de reconeixement molecular en dissolució aquosa i els hem aplicat als materials híbrids orgànic-inorgànics. Així el present treball de Tesis s'ha estructurat en dues parts: per una banda, la síntesis i caracterització de materials sòlids inorgànics porosos funcionalitzats per l'estudi i detecció d'amines utilitzant el procediment de "dosímetre químic", i en una segona part, s'ha realitzat la síntesis i caracterització de sòlids inorgànics porosos funcionalitzats per a l'estudi i detecció d'espècies aniòniques mitjançant el procediment "d'assajos per desplaçament". / Comes Navarro, M. (2016). Hybrid inorganic-organic materials for the optical recognition of neutral and anionic species [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/62153 / Compendio

The experimental data and results demonstrated here illustrate the preparation and application of mesoporous metal oxides in energy storage, adsorption, and catalysis. First, a new method of controlling the pore size and wall thickness of mesoporous silica was developed by controlling the calcination temperature. A series of such silica were used as hard templates to prepare the mesoporous metal oxide Co₃O₄. Using other methods, such as varying the silica template hydrothermal treatment temperature, using colloid silica, varying the materials ratio etc., a series of mesoporous β-MnO₂ with different pore size and wall thickness were prepared. By using these materials it has been possible to explore the influence of pore size and wall thickness on the rate of lithium intercalation into mesoporous electrode. There is intense interest in lithium intercalation into titanates due to their potential advantages (safety, rate) replacing graphite for new generation Li-ion battery. After the preparation of an ordered 3D mesoporous anatase the lithium intercalation as anode material has been investigated. To the best of our knowledge, there are no reports of ordered crystalline mesoporous metal oxides with microporous walls. Here, for the first time, the preparation and characterization of three dimensional ordered crystalline mesoporous α-MnO₂ with microporous wall was described, in which K+ and KIT-6 mesoporous silica act to template the micropores and mesopores, respectively. It was used as a cathode material for Li-ion battery. Its adsorption behavior and magnetic property was also surveyed. Following this we described the preparation and characterization of mesoporous CuO and reduced Cu[subscript(x)]O, and demonstrated their application in NO adsorption and delivery. Finally a series of crystalline mesoporous metal oxides were prepared and evaluated as catalysts for the CO oxidation.

L'objectif de ces travaux de thèse concerne l'étude de l'apport de la chimie supramoléculaire à différents niveaux de la science membranaire. Lors de la première partie de nos travaux, nous avons étudié les capacités d'auto-organisation dynamique de molécules bolaformes. Des études de caractérisations ont permis de déterminer différentes structures, dont la formation de canaux ioniques ou aqueux pour certaines. Les capacités de transport de ces molécules auto-assemblés au sein de bicouches lipidiques a été déterminé. Une autre étude concerne l'utilisation d'un milieu hydrophobe, par des interactions supramoléculaire de type forces de Van der Waals, pour confiner de nouvelles fonctionnalisations dans des matériaux mésoporeux. Différents matériaux, dont les utilisations varient avec les molécules confinées, ont été obtenus et caractérisés par plusieurs méthodes d'analyses. Suite à ces résultats, nous avons spécifiquement étudié et optimisé l'utilisation de matériaux silicés électrodéposés sur la surface d'électrodes, puis fonctionnalisés par des chaînes alkyles, pour former des capteurs électrochimiques en étudiant le cas du fullerène. / The main objective of this study concerns the contribution of supramolecular chemistry at different level of membrane science. During the first part of our work, we have studied the dynamic self-organizing capacities of bolaform molecules. Different characterization techniques allowed us to define different structures, including ion or water channels for some of them. Transport capacities of those self-assembling molecules through lipid bilayers have been determined by several tests. Another study is about the use of a hydrophobic environment, by supramolecular interactions such as Van der Waals forces, to confine new functionalization inside mesoporous materials. Different materials, which use is determined by the confined molecules, have been obtained and characterized by several analysis methods. Furthermore, we have studied and optimized the use of electrodeposited silice materials on electrodes surface, then functionalized by alkyl groups, to form electrochemical captors by studying specifically the fullerene case.

Die geordneten mesoporösen Silikamaterialien SBA-15 und MCM-41 zeichnen sich durch lange zylindrische Poren aus, die auf einem 2D-hexagonalen Gitter arrangiert sind. Auf Grund dieser Eigenschaften finden sie vielfach Anwendung in der Industrie, bieten jedoch auch die Möglichkeit Sorptionsvorgänge und die dadurch induzierten Verformungen auf der Nanometerebene zu untersuchen. Dazu werden im ersten Teil dieser Arbeit Kleinwinkelröntgenstreuungsdaten mit Hilfe eines Formfaktormodells angefittet, um die Adsorption von Fluid in den Poren in Abhängigkeit vom Dampfdruck nachvollziehen zu können. Basierend auf diesen Ergebnissen wird ein Gittermodell eingeführt, welches die Vorgänge während der Sorption mit Hilfe heuristischer Füllmechanismen reproduziert und im Abgleich mit experimentellen Daten Auskunft über die Verteilung der Porosität auf Mikro- und Mesoporen in SBA-15 gibt. Weiterhin wird der Einfluss der begrenzten Geometrie auf die Selbstassemblierung von Tensiden in SBA-15 untersucht. Hierzu werden Neutronenstreudaten durch die Kombination eines Formfaktormodells für die Bragg-Streuung und des Teubner-Strey-Modells für die diffuse Streuung modelliert und interpretiert. Der zweite Teil der Arbeit beschäftigt sich mit den elastischen Verformungen der mesoporösen Materialien durch die Fluidsorption. Dazu wird eine Molekulardynamik-Simulation eines Lennard-Jones-Fluids in einer Schlitzpore vorgestellt, um den Ursprung dieser Verformungen auf der mikroskopischen Ebene zu untersuchen. Diese Ergebnisse fließen anschließend in ein makroskopisches Modell eines ganzen Kristalliten des mesoporösen Materials ein, wodurch ein einfaches Multiskalenmodell entsteht. Die makroskopische Ebene wird dabei durch eine Finite-Elemente-Simulation beschrieben, die im Abgleich mit experimentellen Daten weitere Aussagen über die elastischen Eigenschaften des Materials erlaubt. / The ordered mesoporous silica materials SBA-15 and MCM-41 consist of long cylindrical pores arranged on a 2D-hexagonal lattice. Due to these features, they are used for a range of industrial applications but provide also a possibility to study sorption processes and sorption-induced deformations on the nanoscale. In the first part of this work small-angle X-ray scattering data are fitted with a form factor model in order to examine fluid adsorption in the pores. Based on these results a lattice model is introduced which reproduces the sorption process using heuristic filling mechanisms and clarifies how the porosity of SBA-15 is composed out of micro- and mesopores. Furthermore, the influence of the confined geometry on the self-assembly of surfactants in SBA-15 is studied. For this, neutron scattering data are modeled and interpreted by the combination of a form factor model for the Bragg scattering and the Teubner-Strey model for the diffuse scattering. The second part of this work focuses on the elastic deformations caused by fluid sorption in the mesoporous materials. A Molecular Dynamics simulation of a Lennard-Jones fluid in a slit-pore is presented in order to reveal the origin of these deformations on the microscopic scale. These results are subsequently implemented into a macroscopic model of whole crystallite, thereby creating a simple multi-scale model. The macroscopic scale is modeled with a Finite Elements simulation, which by comparison with experimental data delivers further insights into the elastic properties of the material.

Cette thèse a pour objectif d'améliorer les performances électrochimiques des dispositifs asymétriques C/MnO2 en formulant des oxydes de manganèse présentant des nano- ou mésostructures. Deux méthodes d’élaboration sont explorées. Le matériau mésoporeux est obtenu par réaction entre un agent structurant souple CTAP et divers alcènes A. L’impact des solutions colloïdales CTAP-A sur la texture et la microstructure de MnO2 a été étudié en proposant un modèle qui corrèle la dimension des agrégats avec le diamètre des pores de MnO2. Les performances du dispositif asymétrique sont aussi optimisées. Bien que l’emploi d’un agent structurant dur AAO n’ait pas permis d’élaborer directement un matériau d’électrode MnO2 performant, une microélectrode de MnO2 élaboré sur des nano-piliers de nickel électrodéposé sur AAO montre des propriétés électrochimiques concurrentes avec celles des microélectrodes actuelles. La bonne réponse en puissance élevée du dispositif asymétrique est due à l’excellente connexion entre les piliers et le matériau actif. Ce mémoire offre une meilleure compréhension sur la formation de MnO2 et présente des microélectrodes prometteuses pour les microsupercondensateurs. / The aim of this thesis is to improve the electrochemical performance of C/MnO2 asymmetric devices by elaborating manganese oxides exhibiting nano- or mesostructures. Two preparation methods are proposed. A mesoporous material is obtained through the reaction of soft template CTAP with various A alkenes. The effect of CTAP-A colloidal solution on MnO2 texture and microstructure has been studied by establishing the relationship between aggregates dimension and pore diameter. Asymmetric devices performances can be optimized this way. Attempts to employ AAO as hard template for developing a performant MnO2 electrode were unsuccessful. Nevertheless, a MnO2 microelectrode containing the oxide on nickel nanowires electrodeposited on AAO provided excellent electrochemical performances, comparable with current microsupercapacitor electrodes. Asymmetric device energy retention with increasing power is good due to the excellent MnO2/nickel nanowires connection. This thesis offers insights on the MnO2 formation and proposes promising microelectrodes for microsupercapacitors.

Les ROS (Reactive Oxygen Species), tels H2O2, HO● et O2-●, sont produites naturellementpar le métabolisme des êtres vivants. Cependant, elles peuvent apparaître en trop grandesquantités dans le cas de certaines maladies (Alzheimer, Parkinson, scléroses, cancers). Lasurproduction de ROS conduit à une mortalité des cellules plus élevée.Certains micro-oragnismes possèdent une enzyme à base de Mn capable de catalyser laréaction de dismutation du H2O2 en O2 et H2O. Plusieurs molécules ont été synthétisées pourreproduire ce procédé, cependant très peu d'entre elle sont actives en environnement aqueux.Récemment, des espèces synthétiques du Mn ont été introduites dans des silicesvoient même leur activité catalytique augmenter. Afin de perséverer dans cette voie, cettethèse présente de nouveaux composés de MnII (dinucléaire et chaîne) et MnIII(tetranucléaire) basés sur ce concept. Ils sont dotés de ligands fluorescents, ajoutés pour desfin théragnostiques. Ces composés ont été insérés dans des nanoparticules (NPs) de silice ethybrides carbone-silice afin, de permettre leur vectorisation et d'étudier la compatibilité desNPs hybrides avec ce type de système.Le travail fourni explore les propriétés magnétiques des complexes, les propriétésluminescentes des composés et matériaux et montre la bonne insertion des composés dans lesNPs hybrides, ne nécessitant pas, contrairement aux NPs de silice pure, de fonctionnalisationsupplémentaire pour la rétention des complexes. Il met aussi en évidence l'activité descomposés du Mn dans l'acétonitrile et ouvre des pistes pour une optimisation des systèmeshybrides en milieu aqueux.Le travail fourni explore les propriétés magnétiques des complexes, les propriétésluminescentes des composés et matériaux et montre la bonne insertion des composés dans lesNPs hybrides, ne nécessitant pas, contrairement aux NPs de silice pure, de fonctionnalisationsupplémentaire pour la rétention des complexes. Il met aussi en évidence l'activité descomposés du Mn dans l'acétonitrile et ouvre des pistes pour une optimisation des systèmeshybrides en milieu aqueux. / ROS (Reactive Oxygen Species), such as H2O2, HO● and O2-●, are naturally produced by themetabolism of living beings. However, they can appear in large quantities in the case of certaindiseases (Alzheimer's, Parkinson's, sclerosis, cancer). Overproduction of ROS leads to highercell mortality.Some microorganisms have an Mn-based enzyme capable of catalyzing the disproportionationreaction of H2O2 into O2 and H2O. Several molecules have been synthesized to reproduce thisprocess, however very few of them are active in aqueous environment. Recently, synthetic Mn species have been introduced into mesoporous silica to protect themfrom the environment. Thus, these complexes of Mn are stable and even see their catalyticactivity increase. In order to persevere in this way, this thesis presents new compounds ofMnII (dinuclear and chain) and MnIII (tetranuclear) based on this concept. They havefluorescent ligands (9-anthracene carboxylate), added for theragnostic purposes. Thesecompounds were inserted into silica nanoparticles (Nps), resol (a polyphenol resin) -silica andcarbon-silica hybrids in order to allow their vectorization and to study the compatibility ofhybrid NPs with this type of system.This work explores the magnetic properties of the complexes, the luminescent properties of thecompounds and materials and shows the good insertion of the compounds into the hybrid NPs,not requiring, in contrast to pure silica NPs, additional functionalization for the retention of thecomplexes. It also highlights the activity of Mn compounds in acetonitrile and paves the wayfor optimizing hybrid systems in aqueous media.

Colloidal assemblies of surfactants and polymers in aqueous solutions have been used by human mankind for hundreds of years and they are of great importance in many of our technological processes, such as fabrication of soap and papermaking. Less than two decades ago the idea of using colloidal assemblies as templates of inorganic materials was borne. A new population of materials, referred to as surfactant templated materials, took form. These materials showed extraordinary properties such as monodisperse pore size distribution, large surface areas and pore volumes.   The main focus of this thesis has been on synthesis and functionalisation of spherical mesostructured silica particulate materials. In the first part of the work, mesostructured materials with expanded pores have been produced using a well established aerosol-based method as well as the newly developed emulsion and solvent evaporation (ESE) method. Increase in pore size was realized through using Pluronic block copolymer F127 together with a swelling agent poly(propylene glycol) as template. The influence of the swelling agent on pore size expansion was shown to have a roughly linear relationship. Furthermore, the impact of synthesis parameters on internal and exterior morphology has been investigated. Accessibility of the internal pore space, as well as the external surface roughness were shown to be highly dependent on synthesis temperature. Additionally, a very interesting well ordered 3D closed packed (P63/mmc) material was produced using the ionic surfactant C16TAB as template in the ESE method.   In the second part of the thesis work, mesoporous spheres with large pore size, having either hydrophilic or hydrophobic surface properties, were used as carriers of an enzyme, lipase. The enzymatic activity of lipase was increased onto the hydrophobic surface, compared to lipase immobilized into the hydrophilic support as well as for lipase free in solution. This effect was probably due to a combination of enhanced hydrophobic interactions preventing denaturation of the enzyme and interfacial activation of the enzyme.  This study generated an inorganic carrier material that is a promising candidate for biocatalysis applications. Additionally, mesoporous spheres were used as carriers of a model drug, Ibuprofen, to study the effect of polyelectrolyte multilayers on release properties. However, these layers were shown impermeable independent on pH and the substance was only released from uncoated particles. / <p>QC 20100811</p>

Organic-inorganic nanostructured composites are nowadays integrated in the field of material science and technology. They are used as advanced materials directly or as precursors to novel composites with potential applications in optics, mechanics, energy, catalysis and medicine. Many properties of these complex materials depend on conformational rearrangements in their inherently dynamic organic parts. The focus of this thesis is on the study of the molecular mobility in ordered nanostructured composites and lyotropic mesophases and also on the development of relevant solid-state NMR methodologies. In this work, a number of new experimental approaches were proposed for dipolar NMR spectroscopy for characterizing molecular dynamics with atomic-level resolution in complex solids and liquids. A new acquisition scheme for two-dimensional dipolar spectroscopy has been developed in order to expand the spectral window in the indirect dimension while using limited radio-frequency power. Selective decoupling of spin-1 nuclei for sign-sensitive determination of the heteronuclear dipolar coupling has been described. A new dipolar recoupling technique for rotating samples has been developed to achieve high dipolar resolution in a wide range of dipolar coupling strength. The experimental techniques developed herein are capable of delivering detailed model-independent information on molecular motional parameters that can be directly compared in different composites and their bulk analogs. Solid-state NMR has been applied to study the local molecular dynamics of surfactant molecules in nanostructured organic-inorganic composites of different morphologies. On the basis of the experimental profiles of local order parameters, physical motional models for the confined surfactant molecules were put forward. In layered materials, a number of motional modes of surfactant molecules were observed depending on sample composition. These modes ranged from essentially immobilized rigid states to highly flexible and anisotropically tumbling states. In ordered hexagonal silica, highly dynamic conformationally disordered chains with restricted motion of the segments close to the head group have been found. The results presented in this thesis provide a step towards the comprehensive characterization of the molecular states and understanding the great variability of the molecular assemblies in advanced nanostructured organic−inorganic composite materials. / <p>QC 20150225</p>