Dissertations / Theses on the topic 'Organic-inorganic Hybrid Mesoporous Materials'

[ES] El trabajo de investigación descrito en la presente Tesis Doctoral ha sido desarrollado en el marco del proyecto europeo MULTI2HYCAT (grant agreement N. 720783) y se ha centrado en la síntesis y caracterización de materiales mono- y multi-funcionales que presentan sitios catalíticos ácidos, básicos o redox. Diferentes líneas de investigación han sido desarrolladas en paralelo para obtener distintos materiales híbridos que serán empleados en diferentes procesos catalíticos, en línea con las necesidades de los socios industriales del proyecto. Debido a la naturaleza colaborativa del proyecto, cada miembro académico se ha en-centrado en un aspecto del desarrollo de los materiales. Es por ello que el Instituto de Tecnología Química (ITQ-CSIC), donde se ha llevado a cabo esta Tesis Doctoral, se ha centrado en la síntesis de los catalizadores híbridos. Por ello, parte de la caracterización descrita en el Capítulo 3 se ha llevado a cabo en la Università del Piemonte Orientale (IT), durante una estancia de un mes. Ademas, algúnos resultados catalíticos descritos en los Capítulos 3 y 5 han sido obtenidos por la University of Southampton (UK). En el Capítulo 3, se ha descrito la síntesis de dos catalizadores heterogéneos híbridos que presentan moléculas de ácido aril-sulfónico en su composición. En uno de ellos, el anillo aromático presentará átomos de flúor en posición 2, 3, 5, 6. Se han llevado a cabo dos estrategias de síntesis multi-etapas, a través de la síntesis de los precursores alkoxi-silanos, a través de procesos de condensación junto a un precursor de sílice (en ausencia de agentes directores de estructura, a pH neutro y temperaturas bajas) y de una reacción de tethering. Los materiales híbridos han sido caracterizados a través de dife-rentes técnicas. Las propiedades texturales, la estabilidad térmica y la composición química de los catalizadores ha sido estudiada. Además, moléculas sondas han sido adsorbidas en los materiales hibridos y las interacciones entre ellos han sido estudiadas a través de espectroscopias FTIR y RMN multi-nuclear. El catalizador hibrido en que el anillo aromático estaba fluorado resultó ser el más activo catalíticamente en la reac-ción de formación de acetal entre benzaldehído y etilenglicol. Una versión de los hí-bridos en que la superficie había sido pasivada con grupos metilos también fue obteni-da. Las propiedades de los materiales híbridos pasivados fueron comparadas, para po-der estudiar el efecto de la polaridad de la superficie del soporte sobre la actividad catalítica. En el Capítulo 4 se describe la síntesis de órgano-catalizadores híbridos obtenidos por anclaje de precursores de silicio funcionalizados con grupos básicos sobre un soporte del tipo MCM-41. Los catalizadores han sido caracterizados y empleados en diferentes reacciones de formación de enlaces C-C, como la condensación de Knoevenagel y la adición de Michael. Los catalizadores híbridos han sido empleados en la condensación entre furfural y metil isobutil cetona. El catalizador más activo ha sido seleccionado para ser funcionalizado posteriormente con nanoparticulas de paladio y empleado en un proceso catalítico en cascada. Mecanismos de reacción han sido pro-puesto para cada proceso catalítico. El efecto beneficioso debido a la presencia de los grupos silanoles en la superficie del soporte también fue analizado. En el Capítulo 5, la síntesis de catalizadores híbridos multi-funcionales fue descrita. Basándose en los resultados obtenidos en el Capítulo 4, se ha preparado un catalizador que presente grupos aminopropil- y nanopartículas de paladio. Las propiedades estructurales y texturales han sido estudiadas. Además, a través de la microscopia electrónica de transmisión, la distribución dimensional de las nanoparticulas ha sido estimada, resultando en un tamaño medio equivalente a la dimensión de los canales mesoporosos del soporte, MCM-4
[CA] El treball de recerca descrit en aquesta tesi doctoral es va desenvolupar en el marc del projecte europeu MULTI2HYCAT (grant agreement N. 720783) i se centra en la sínte-si i la caracterització de catalitzadors híbrids mono i multifuncionals amb àcid, base o redox actius llocs. S'han desenvolupat diverses línies d'investigació en paral·lel per dissenyar múltiples catalitzadors híbrids per a diferents processos catalítics, basant-se en les necessitats dels socis industrials. A causa del caràcter col·laboratiu del projecte, cada soci acadèmic es va centrar princi-palment en un aspecte de tot el procés. Institut de Tecnologia Química (ITQ-CSIC), on es va desenvolupar aquesta tesi, està principalment centrat en el disseny i síntesi de catalitzadors híbrids. Per això, part dels resultats de caracterització reportats al Capítol 3 s'han dut a terme a la Università del Piemonte Orientale (IT), durant una estada d'un mes. Alguns dels resultats catalítics reportats al Capítol 3 i al Capítol 5 han estat reali-tzats per la Universitat de Southampton (Regne Unit). En el Capítol 3, s'ha descrit la síntesi de dos catalitzadors heterogenis híbrids que pre-senten molècules d'àcid aril-sulfònic en la composició. En un d'ells, l'anell aromàtic presentarà àtoms de fluor en posició 2, 3, 5, 6. S'han dut a terme dues estratègies de síntesi multi-etapes, a través de la síntesi dels precursors alkoxi-silans, mitjançant pro-cessos de condensació al costat d'un precursor de sílice (en absència d'agents directors d'estructura, a pH neutre i temperatures baixes) i d'una reacció de tethering. Els mate-rials híbrids han estat caracteritzats mitjançant diferents tècniques. Les propietats texturals, l'estabilitat tèrmica i la composició química dels catalitzadors ha sigut estudiada. A més, molècules sondes han estat adsorbides en els materials híbrids i les interaccions entre ells han estat estudiades mitjançant espectroscòpies FTIR i RMN multi-nuclear. El catalitzador híbrid en que l'anell aromàtic estava fluorat va resultar ser el més actiu catalíticament en la reacció de formació d'acetal entre benzaldehid i etilenglicol. Una versió dels híbrids en que la superfície havia estat pasivada amb grups metilos també va ser obtinguda. Les propietats dels materials híbrids passivats van ser comparades, per poder estudiar l'efecte de la polaritat de la superfície del suport sobre l'activitat catalítica. En el Capítol 4 es descriu la síntesi d'organo-catalitzadors híbrids obtinguts per ancoratge de precursors de silici funcionalitzats amb grups bàsics sobre un suport del tipus MCM-41. Els catalitzadors han estat caracteritzats i empleats en diferents reaccions de formació d'enllaços C-C, com la condensació de Knoevenagel i l'addició de Michael. Finalment, els catalitzadors híbrids han estat emprats en la condensació entre furfural i metil isobutil cetona. El catalitzador més actiu ha estat seleccionat per a ser funcionalitzat posteriorment amb nanoparticules de pal·ladi i emprat en un procés catalític en cascada. Mecanismes de reacció han estat proposat per a cada procés catalític. L'efecte beneficiós a causa de la presència dels grups silanols en la superfície de suport també va ser analitzat. En el Capítol 5, la síntesi de catalitzadors híbrids multi-funcionals va ser descrita. Basant-se en els resultats obtinguts en el Capítol 4, s'ha preparat un catalitzador que presenti grups aminopropil- i nanopartícules de palladi. Les propietats estructurals i texturals han estat estudiades. A més, a través de la microscòpia electrònica de trans-missió, la distribució dimensional de les nanoparticulas ha estat estimada, resultant en una grandària mitjana equivalent a la dimensió dels canals mesoporosos del suport, MCM-41. El material ha estat emprat com a catalitzador multi-funcional.
[EN] The research work described in this Doctoral Thesis was developed within the frame of the MULTI2HYCAT European Project (grant agreement N. 720783) and it is focused on the synthesis and characterization of mono- and multi-functional hybrid catalysts featuring acid, base or redox active sites. Several research lines have been developed in parallel to design multiple hybrid catalysts for different catalytic processes, building upon the needs of the industrial partners. Due to the collaborative nature of the project, each academic partners mainly focused on one aspect of the whole process. Instituto de Tecnología Química (ITQ-CSIC), where this Thesis was developed, mostly focused on the design and synthesis of the hybrid catalysts. For that, part of the characterization results reported in Chapter 3 have been carried out at Università del Piemonte Orientale (IT), during a one month stay. Some of the catalytic results reported in Chapter 3 and Chapter 5 have been car-ried out by the University of Southampton (UK). In Chapter 3 the synthesis of two different heterogeneous hybrid catalysts carrying aryl-sulfonic moieties, in which the aromatic ring was either fluorinated or not, is re-ported. Two multi-step synthetic approaches were developed, involving the synthesis of the silyl-derivative precursor, template-free one-pot co-condensation (at low tem-perature and neutral pH) and tethering reaction. A multi-technique approach was im-plemented to characterize the hybrid catalysts. Textural properties, thermal stability and chemical makeup of the materials were studied. Moreover, probe molecules were adsorbed onto the hybrids and the interaction were studied with multi-nuclear NMR and FTIR spectroscopies. The catalytic activity of the two hybrids showed superior performances for the fluoro-aryl-sulfonic acid, compared to the non-fluorinated mate-rial, in the acetal formation between benzaldehyde and ethylene glycol. Silanol-capped versions of the hybrids have also been prepared and their properties have been com-pared with those of hydrophilic hybrids, to study the effect of the polarity of the sur-face on the overall catalytic activity of the hybrids. In Chapter 4, the synthesis of hybrid mesoporous organocatalysts, obtained by graft-ing of commercial and custom-made silyl-derivatives onto MCM-41 supports, is re-ported. The hybrid catalysts were characterized and tested for different reactions in-volving C-C bond formation, such as Knoevenagel condensations and Michael addi-tion. Finally, the catalysts were tested in the condensation between furfural and methyl isobutyl ketone and the most performing catalyst was selected for the synthesis of a multi-functional hybrid. Reaction mechanisms have been proposed and the beneficial effect of the surface silanol groups on the catalytic activity was demonstrated. In Chapter 5, the synthesis of hybrid multi-functional catalysts is reported. Building upon the results reported in Chapter 4, a hybrid catalyst featuring aminopropyl moie-ties and palladium nanoparticles was developed. Structural and textural properties of the catalysts were accessed. Moreover, transmission electron microscopy showed a narrow nanoparticles distribution, centered a value equivalent to the size of the meso-porous channels of the support. The catalyst was tested in a tandem process involving the aldol condensation between furfural and methyl isobutyl ketone followed by hy-drogenation of the aldol adduct. The influence of several variables on the activity of the multi-functional catalyst was explored, with the scope of paving the way for more thorough studies to be carried out in flow regime. Lastly, proof-of-concept syntheses of multi-functional hybrid catalysts featuring base sites and supported metal complex are reported.
The research work described in this Doctoral Thesis was developed within the frame of the MULTI2HYCAT European Project (grant agreement N. 720783). I would like to thank la Caixa foundation for my PhD scholarship.
Erigoni, A. (2021). Organic-Inorganic Hybrid Catalysts for Chemical Processes of Industrial Interest [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/165238
TESIS

Ce mémoire rapporte la préparation et l'étude de matériaux hybrides organiques-inorganiques à base de titane où les deux réseaux sont liés par des liaisons titane-carbone stables. Différents précurseurs dans lesquels deux groupes cyclopentadienyltitane sont reliés par des espaceurs variés ont été préparés. Ces espaceurs comprennent des groupes aromatiques et hétéroaromatiques linéaires ainsi que des groupes aromatiques disubstitués par des chaînes alkyle. Ces complexes dimétalliques, où le titane est aussi lié à trois groupes labiles, ont été ensuite hydrolysés dans les conditions du procédé sol-gel pour conduire à des hybrides de classe II. Le réseau organique y est lié au réseau inorganique par des liaisons stables titane-carbone. Ces matériaux sont organisés et leur mode d'organisation dépend de la nature de l'espaceur reliant les groupes cyclopentadienyle. Les espaceurs linéaires conduisent à des matériaux à structure en escalier dans lesquels les ligands sont associés par des liaisons p. La longueur des espaceurs n'a pas d'effet sur cette organisation. Par contre, les matériaux à espaceurs substitués latéralement sont organisés par les chaînes alkyle. La calcination de ces matériaux hybrides sous oxygène conduit à la formation de dioxyde de titane nanoporeux sous forme d'anatase dont la cristallinité et la surface spécifique dépendent de la température de calcination. D'une façon similaire des films de dioxyde de titane de même type sont obtenus par la calcination de films minces d'hybrides préparés par spin-coating
This work aimed to the preparation of titanium-based organic-inorganic hybrid materials where both networks are linked through stable titanium-carbon bonds. The preparation of various di(cyclopentadienyltitanium) precursors in which various organic groups serve as a bridge between the two cyclopentadienyl groups while each titanium atom is equipped with three hydrolysable groups was first achieved. Then, these complexes were hydrolyzed in a sol-gel process that led to new self-assembled titanium-based class II hybrid materials in which the inorganic network is connected to the organic network through stable titanium-carbon bonds. The mode of organization of the nanostructures depends on the spacer bridging the cyclopentadienyl groups. Linear aromatic spacers led to materials having a stair-like structure in which the organic ligands are arranged via p-stacking. The length of the spacer has a little effect on the organization of the nanostructures. The structure of the materials obtained with spacers endowed with long lateral chains is governed by the side chains. The calcination of these materials under oxygen led to the formation of nanoporous anatase titanium dioxide the crystallinity and surface area of which depend on the calcination temperature. Similarly titanium dioxide thin films were prepared by the calcination of hybrid thin films prepared by spin coating

[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 no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/62153
TESIS

Thesis (Ph.D)--Chemical Engineering, Georgia Institute of Technology, 2008.
Committee Chair: Jones, Christopher; Committee Member: Koros, William; Committee Member: Lyon, Andrew; Committee Member: Nair, Sankar; Committee Member: Weck, Marcus. Part of the SMARTech Electronic Thesis and Dissertation Collection.

Nanotechnology as a field has the potential to answer some of the major challenges that mankind faces in regards to environmental sustainability, energy generation and health care. Though, solutions to these concerns can not necessarily rely on our current knowhow. Instead, it is reasonable to expect that humanity must adapt and learn to develop new materials and methods to overcome the adversities that we are facing. This master thesis has involved developing novel materials, serving as a small step in the continuous march towards a bright future where this is possible. More specifically, this work sought to combine mesoporous magnesium carbonate with various metal-organic frameworks to utilize the beneficial aspects from each of these constituents. The ambition was that these could be joined to render combined micro-/mesoporous core-shell structures, with high surface areas and many active sites whilst maintaining a good permeability. Numerous different synthesis routes were developed and explored in the pursuit of viable routes to design novel materials with potential future applications within for instance drug delivery, water harvesting from air and gas adsorption. Coreshell structures of the hydrophilic mesoporous magnesium carbonate covered with the hydrophobic zeolitic imidazole framework ZIF-8 was successfully synthesized for the first time, and practical studies demonstrated a dramatically enhanced water stability, which is perceived to have an impact on further research on these materials. ZIF-67 was also combined with mesoporous magnesium carbonate in a similar manner. Further, Mg-MOF-74 was grown directly from mesoporous magnesium carbonate, where the latter acted as a partially self-sacrificing template, with the aim of rendering a porous hierarchical structure with contributions from the micro- and mesoporous ranges. The outcomes of all these syntheses were characterized using several analyzing methods such as scanning electron microscopy, X-ray diffraction, energy dispersive spectroscopy and nitrogen sorption analysis.

Novel highly functionalized hybrid organic-inorganic materials were synthesized by polycondensation of bis[3-(trimethoxysilyl)propyl]amine in presence of cationic and anionic surfactants. Reaction media strongly affected gelation time. Thus, in basic media gelation occurred immediately while acid increased gelation time. Material structures were studied by IR spectroscopy, porosimetry, XRD, and SAXS methods. In spite of the absence of an inorganic linker, obtained bridged silsesquioxanes had mesoporous structure. A material prepared in the presence of dodecylamine as a template had higher surface area and narrow pore size distribution while the use of sodium dodecylbenzene sulfate resulted in formation of mesopores with wide size ranges. Accessibility of surface amine groups in silsesquioxanes was studied for molecules of acidic nature and different sizes: HCl, CO2 and picric acid. High contents of accessible amine groups in these materials make them prospective adsorbents for post-combustion CO2 capture.

L'objectif de cette thèse est la synthèse, la caractérisation et l'étude de complexes métalliquesluminescents, en particulier de Pt (II), leurs propriétés d'agrégation en solution, mais également dansun espace confiné ainsi qu’en surface. L'incorporation de complexes de métaux de transition dans lastructure poreuse, et ainsi que leur dépôt à la surface de nanoparticules et dans un cadre métalloorganique(MOF), par greffage post-synthétique, ont été étudiés. Sont également étudiés lacorrélation entre les propriétés de films d’une série de complexes de Pt(II) avec leur morphologie,leur mobilité électronique et la simulation de leur structure auto-assemblée par diffraction auxrayons-X. Les propriétés de luminescence de complexes amphiphiles de Pt(II) sont améliorées àl’intérieur de nanoparticules de silice mesoporeuse par la création d’un d’espace confiné. Un effetsimilaire est observé par le dépôt de complexes de Pt(II) fonctionnalisés sur une surface denanoparticules d’or. La luminescence d’un cadre organométallique a été modifiée par greffage postsynthétiquede complexes d’Ir(III) et de Pt(II)
The aim of this thesis is the synthesis, characterization and investigation of luminescent metalcomplexes, and in particular of Pt(II) compounds, their aggregation properties in solution but inconfined space as well. The incorporation of transition metal complexes in porous structure, and inparticular in a metal-organic framework (MOF), by post-synthesis grafting, have been investigated.Luminescence properties of amphiphilic Pt(II) complexes were enhanced inside mesoporous silicananoparticles by the creation of a confined space. Similar effect is observed by deposition offunctionalized Pt(II) complexes on gold nanoparticles surface. Luminescence of metal organicframework was tuned by post-synthetic grafting of Ir(III) and Pt(II) complexes

This dissertation addresses two topics associated with the assembly of surfactants at the solid-liquid interface for adsorption and materials synthesis. The first is the adsorption of an anionic fluorinated surfactant, tetraethylammonium perfluorooctylsulfonate (TEA-FOS), at the solid/liquid interface. Attenuated total reflection Fourier transform infrared spectroscopy is used to study the adsorption kinetics and average orientation of surfactants at the hydroxylated germanium surface. Atomic force microscopy provides complementary images of the adsorbed layer structure on mica. The adsorption follows unusual three-stage kinetics in which the rate of adsorption starts fast, slows as the surface becomes crowded, and then (surprisingly) accelerates due to nucleation of a heterogeneous multilayer structure. These fast-slow-fast three stage adsorption kinetics are observed for a wide range of concentrations at pH 6, and the rates of the three stages are modulated by pH and salt by tuning electrostatic interactions among surfactants, counterions, and the surface. The results suggest that tetraethylammonium mediates interactions between surfactants and with negatively charged surfaces. The dichroism measurements and AFM are consistent with a mechanism in which TEA-FOS first forms an incomplete layer with chains oriented randomly or somewhat parallel to the surface, followed by formation of flattened multilayer clusters with the chains oriented somewhat normal to the substrate. The second topic is the sol-gel synthesis of mesoporous silica materials using dual surfactant templates. Studies of templating with mixed cetyltrimethylammonium bromide and octyl-beta-D-glucopyranoside surfactants shows that the ternary phase diagram of surfactants in water can be used to predict mesoporous materials structure, and that vapor-phase ammonia treatments can either stabilize the structure or induce swelling by the Maillard reaction. Studies of sol-gel reaction-induced precipitation with demixed hydrocarbon and fluorocarbon cationic surfactant micelles show a wide variety of pore structures. A number of synthesis parameters are adjusted to tune the pore structure, for instance to adjust the size and populations of bimodal mesopores. Selective swelling of the two surfactants by liphophilic and fluorophilic solvents is observed. Finally, proteinaccessible hollow spherical silica particles with mesoporous shells are reported. The methods for engineering mesoporous materials reported here have potential applications in adsorption, controlled drug delivery and for catalysis.

La recherche de nouveaux matériaux en tant que photocatalyseurs en lumière visible pour la dépollution de l’environnement (eaux, atmosphères) est un domaine de recherche très actif et suscite l’intérêt d’une large communauté scientifique en Physique, Chimie et Sciences des matériaux. Des recherches exhaustives sont actuellement menées pour améliorer l’efficacité photocatalytique de certaines classes de matériaux photoactifs connus, et pour développer la synthèse de nouveaux matériaux fonctionnels. Dans ce contexte, les semiconducteurs oxydes photoactifs à base de vanadates de bismuth (BiVO4) possédant une bande électronique au milieu du spectre visible, offrent une sérieuse alternative aux photocatalyseurs classiques efficaces (TiO2, ZnO) dont la photo-excitation requiert uniquement la fraction UV du spectre solaire. Le travail effectué dans le cadre de cette thèse est donc dédié aux matériaux à base BiVO4 sous forme d’architectures mésoporeuses ou d’assemblages hybrides associant des groupes organiques à transfert de charges.Deux contributions majeures ont été développées dont la première portant sur la réalisation expérimentale d’architectures mésoporeuses inédites, fonctionnalisées par des groupes organiques sensibilisateurs et l’étude de leurs propriétés électroniques et optiques en vue d’optimiser leurs efficacités photocatalytiques. La deuxième partie porte sur des simulations numériques de nanostructures hybrides par des approches exploitant la méthode DFT, ab-initio ou des modèles de chimie quantique. Des systèmes modèles ont été construits associant des nanoclusters (NC) et des groupes organiques (GO). Les propriétés électroniques et optiques ainsi que les caractéristiques structurelles et vibrationnelles des systèmes (NC-GO) ont été déterminées et confrontées aux données expérimentales. Les phénomènes de transfert de charges impliqués entre les groupes organiques et la structure inorganique ont été caractérisés ainsi que leur rôle dans l’efficacité des réponses photo-catalytiques des systèmes hybrides
The search for new materials as photocatalysts invisible light for the depollution of the environment (waters, atmospheres) is a very active field of research and attracts the interest of a large scientific community in Physics, Chemistry and Materials Science. Recent research developpements are conducted to improve the photocatalytic efficiency of certain classes of known photoactive materials, and to develop the synthesis of new functional materials. In this context, photoactive oxide semiconductors based on bismuth vanadate (BiVO4) having an electronic band in the middle of the visible spectrum, offer a serious alternative to efficient conventional photocatalysts (TiO2, ZnO) whose photo-excitation requires only the UV fraction of the solar spectrum.The work done in this thesis is therefore dedicated toBiVO4-based materials in the form of mesoporous architectures or hybrid assemblies associating organic groups with charge transfer processes. Two major contributions have been developed, one of which is the experimental realization of novel mesoporous architectures, functionalized by sensitizing organic groups and the study of their electronic and optical properties in order to optimize their photocatalytic efficiencies. The second part deals with numerical simulations of hybrid nanostructures using approaches as the DFT method, ab-initio or quantum chemistry codes. Model systems have been constructed associating BiVO4nanoclusters (NC) and organic groups (GO). The electronic and optical properties as well as the structural and vibrational characteristics of the systems (NC-GO) were determined and compared with the experimental data. The charge transfer phenomena involved between the organic groups and the inorganic structure were characterized as well as their role in the efficiency of photo-catalytic responses of hybrid systems

[EN] Abstract The present PhD thesis entitled "Supramolecular Chemistry: New chemodosimeters and hybrid materials for the chromo-fluorogenic detection of anions and neutral molecules" is based on the application of supramolecular chemistry and material science principles for the development of optical chemosensors for anions and neutral molecules detection. The second chapter of this PhD thesis is devoted to the preparation of chemodosimeters for the chromo-fluorogenic detection of fluoride, diisopropyl fluorophosphates (DFP) and hydrogen sulfide. The optical detection of fluoride anion was achieved by using a pyridine derivative containing a t-butyldimethylsilyl ether group. Aqueous solutions of the chemodosimeter were colorless but turned yellow upon addition of fluoride anion. Also a remarkable enhancement in emission was observed only upon the addition of fluoride. The optical changes were ascribed to a fluoride-induced hydrolysis of the silyl ether moiety. Also a chemodosimeter for the optical recognition of DFP, a nerve agent simulant, was prepared. In this case, the chemodosimeter was based on a stilbene pyridinium derivative functionalized with hydroxyl and silyl ether moieties. Aqueous solutions of the chemodosimeter were colorless changing to yellow upon DFP addition. The optical changes were ascribed to a hydroxyl phosphorylation followed by a fluoride-induced hydrolysis of the silyl ether group. Besides, that probe was implemented in test strips and DFP detection in gas phase was accomplished. Finally, the fluorogenic recognition of hydrogen sulfide anion was explored. For this purpose different fluorophores were selected and fucntionalized with 2,4-dinitrophenyl ether groups. The prepared probes were neraly non-emissive but remarkable emission enhancements upon addition of hydrogen sulfide were observed. The emission enhancements observed were due to a selective sulfide-induced hydrolysis of the 2,4-dinitrophenyl ether moiety that yielded the free fluorophores. Another set of chemodosimeters equipped with azide and sulfonylazide moieties were prepared. Again these probes were non-fluorescent but upon addition of hydrogen sulfide an important enhancement in emission was found. The selective response was ascribed to a reduction of the azide and sulfonylazide moieties to amine and sulfonylamide induced by hydrogen sulfide anion. Besides, the viability assays showed that these dosimeters were essentially non-toxic and real-time fluorescence imaging measurements confirmed their ability to detect intracellular hydrogen sulfide at micromolar concentrations. The third chapter of this PhD thesis was devoted to the preparation of nanoscopic gated materials and their use in sensing protocols. In a first step a gated material for the optical detection of glutathione (GSH) was prepared. For this purpose MCM-41 mesoporous silca nanoparticles were selected as inorganic scaffold. The pores were loaded with safranine O and the external surface was functionalized with disulfide-containing oligo(ethylene glycol) moieties. Dye delivery from aqueous suspensions of the sensory material was only observed in the presence of GSH. The signalling paradigm was ascribed to the selective reduction of the disulfide bond by GSH which induced pore opening and dye release. Also capped organic-inorganic hybrid materials for the selective detection of hydrogen sulfide were prepared and characterized. In this case the same MCM-41 support was used and charged with [Ru(bipy)3]2+ dye. Then, the external surface was functionalized with Cu(II)-macorcyclic complexes and finally, the pores were capped by the addition of the bulky anion hexametaphosphate. Aqueous suspensions of this material showed negligible dye release whereas in the presence of hydrogen sulfide anion a remarkable colour change was observed. This optical response was ascribed to a demetallation process of the Cu(II) complex induced by hydrogen sulfide.
[ES] Resumen La presente tesis doctoral titulada "Química supramolecular: Nuevos dosímetros químicos y materiales híbridos para la detección cromo-fluorogénica de aniones y moléculas neutras." está basada en la aplicación de principios básicos de la química supramolecular y de la ciencia de materiales en el desarrollo de sensores ópticos para aniones y moléculas neutras. El segundo capítulo de esta tesis doctoral está dedicado a la preparación de dosímetros químicos para la detección cromo-fluorogénica de fluoruro, diisopropil fluorofosfato (DFP) y sulfuro de hidrógeno. Para la detección óptica del anión fluoruro se sintetizó un derivado de piridina funcionalizado con un t-butildimetilsilil éter. En este capítulo también se describe la preparación de un dosímetro químico para la detección de DFP, que es un simulante de agentes nerviosos. Este dosímetro está basado en un estilbeno funcionalizado con una sal de piridinio que contiene grupos hidroxilo y silil éter en su estructura. Finalmente se prepararon dos familias de sensores para la detección óptica de hidrógeno sulfuro. La primera familia de sensores consiste en fluoróforos comunes funcionalizados con 2,4-dinitrofenil éteres. Los sensores preparados no presentaron una emisión de fluorescencia importante mientras que, en presencia del anión hidrógeno sulfuro, se observó un aumento significativo. La segunda familia de dosímetros también estaba compuesta por ciertos fluorofóros pero, en este caso, funcionalizados con grupos azida y sulfonilazida. Los dosimétros preparados, siguiendo esta segunda aproximación, tampoco dieron una fluorescencia significativa observándose un aumento de la misma al añadir el anión hidrógeno sulfuro. El tercer capítulo de esta tesis doctoral está dedicado a la preparación de materiales híbridos nanoscópicos funcionalizados con puertas moleculares y su aplicación en protocolos de reconocimiento. En primer lugar se preparó un material para la detección óptica de glutatión (GSH). Para ello se emplearon nanopartículas de MCM-41 mesoporosas como soporte inorgánico. Los poros del soporte fueron cargados con el colorante safranina O y la superficie externa funcionalizada con oligo(etilenglicol) conteniendo enlaces disulfuro. También se prepararon y caracterizaron varios materiales híbridos para la detección selectiva del anión hidrógeno sulfuro. En este caso también se empleó, como soporte inorgánico, sílice mesoporosa MCM-41. Los poros del soporte inorgánico fueron cargados con [Ru(bipy)3]2+ y la superficie externa funcionalizada con varios complejos macrocíclicos de Cu(II). El material sensor final fue obtenido al añadir el anion hexametafosfato, que compleja con los complejos de Cu(II), produciendo un bloqueo de los poros.
[CAT] Resum La present tesi doctoral titulada "Química supramolecular: Nous dosímetres químics i materials híbrids per a la detecció cromo-fluorogènica d'anions i molècules neutres." està basada en l'aplicació dels principis bàsics de la química supramolecular i de la ciència dels materials en el desenvolupament de sensors òptics per a anions i molècules neutres. El segon capítol d'aquesta tesi doctoral està dedicat a la preparació de dosímetres químics per a la detecció cromo-fluorogènica de fluorur, diisopropil fluorofosfat (DFP) i sulfur d'hidrogen. Per a la detecció òptica de l'anió fluorur es va sintetitzar un derivat de piridina funcionalitzat amb un t-dibutildimetilsilil èter. En aquest capítol també es descriu la preparació d'un dosímetre químic per a la detecció de DFP, que és un simulant d'agents nerviosos. Aquest dosímetre està basat en un estilbè funcionalitzat amb una sal de piridina que conté grups hidroxil i silis èter en la seua estructura. Finalment varen ser preparades dues famílies de sensors per a la detecció òptica de sulfur d'hidrogen. La primera família consisteix en fluoròfors comuns funcionalitzats amb 2,4-dinitrofenil èters. Els sensors preparats no presentaren una emissió de fluorescència significativa mentre que, en presencia de l'anió hidrogen sulfur, es va observar un augment significatiu. La segona família de dosímetres també estava composada per certs fluròfors però, en aquest cas, funcionalitzats amb grups azida i sulfonilazida. Els dosímetres preparats, seguint aquesta segona aproximació, tampoc donaren una fluorescència significativa observant-se un augment de la mateixa al afegir l'anió hidrogen sulfur. El tercer capítol d'aquesta tesi doctoral està dedicat a la preparació de materials híbrids nanoscòpics funcionalitzats amb portes moleculars i la seua aplicació en protocols de reconeixement. En primer lloc es va preparar un material per a la detecció òptica de glutatió (GSH). Per a aquest propòsit es varen emprar nanopartícules MCM-41 mesoporoses com a suport inorgànic. Els porus del suport varen ser carregats amb el colorant safranina O i la superfície externa funcionalitzada amb oligo(etilenglicol) que contenia enllaços disulfurs. També varen ser preparats i caracteritzats diversos materials híbrids per a la detecció selectiva de l'anió hidrogen sulfur. En aquest cas també es va emprar, com a suport inorgànic, sílice mesoporosa MCM-41. Els porus del suport inorgànic varen ser carregats amb [Ru(bipy)3]2+ i la superfície externa funcionalitzada amb diversos complexos macrocíclics de Cu(II). El material sensor final es va obtindre al afegir l'anió hexametafosfat, que es complexa amb macrocicles de Cu(II), produint un bloqueig dels porus.
El Sayed Shehata Nasr, S. (2015). Supramolecular Chemistry: New chemodosimeters and hybrid materials for the chromo-fluorogenic detection of anions and neutral molecules [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/52598
TESIS

The goal of the work presented in this thesis, was to develop inorganic material systems synthesized via organic precursors and to pattern them using different lithographic techniques. The materials investigated were the ferromagnetic Ni metal and the mesoporous TiO2 and Nb2O5, which have applications in dye sensitized solar cells. The first part of the thesis presents an overview of pattern formation in organic and inorganic materials and the working principles of dye sensitized solar cells. Next the theoretical background of block-copolymer and block-copolymer structure directing hybrid materials are described. Fundamental knowledge of magnetism and ferromagnetism are also presented. The techniques used to characterize the material and the fabricated devices are detailed. For example, the samples were characterized using magnetic force microscopy (MFM) and scanning electron microscopy (SEM), while the materials were characterized by BET. The fabrication of Ni metal films using sol-gel process is then discussed. The Ni metal films were patterned with sub-10 nm wide lines via direct-writing electron beam lithography, and their electrical resistivity was investigated. The in uence of mesoporous TiO2 obtained using a block-copolymer, which acted as a structure-directing agent for the metal oxide, is then presented. This material was incorporated into solid state dye sensitized solar cells. The development of a mesoporous material fabrication protocol, which has significantly in uenced solar cell efficiency, is discussed. Finally the general ideas and some preliminary results on a mesoporous Nb2O5 material and its application in dye sensitized solar cells are presented.

Two types of coating materials were prepared by a sol-gel process and classified into two systems. In system I, four different types of the optically transparent organic-inorganic hybrid coating materials produced by The Welding Institute (TWI) using a patent method called Vitresyn, identical in terms of the precursors, but different in terms of their relative proportions, were examined. The precursors used for system I were tetraethoxysilane (TEOS), 3-(trimethoxysilyl)propyl methacrylate (MPTMA) and an aliphatic urethane acrylate. The coating materials were deposited on aluminium, brass and polycarbonate substrates by a flow coating method, and cured under a UV lamp for various times from 2 minutes to 40 minutes. In system II, MPTMA, Methyltrimethoxysilane (MTMS) and trimethoxysilypropyl acrylate (PATMS) were used as precursors. No urethane acrylate was used in this system. TEOS was used in system I as the primary inorganic precursor and urethane acrylate was used as the source of organic component. MPTMA was used as both a secondary inorganic source and a coupling agent between the organic and inorganic phases. To ascertain the interaction relationships between organic and inorganic phases in the hybrid materials, Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance spectroscopy (NMR) were used. It was found that a siloxane (Si­O-Si) network is a backbone of the hybrid materials and that the network increases with increasing inorganic content in the hybrid materials. These organic-inorganic hybrid materials were mainly cross-linked by T³, Q³ and Q⁴ species. It was also found that UV curing leads to accelerated condensation reaction through the opening of C=C bonds in MPTMA and urethane acrylate. Microstructures in the coatings and interfaces between the coatings and the substrates were investigated by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The coating thickness is dependent on the relative amount of organic resin added to the hybrid materials. The coating thickness increases as more organic resin (urethane acrylate) is used. Neither silica domains nor pores were observed in the coatings. It was concluded that the hybrid coating materials are a single featureless amorphous phase regardless of the organic/inorganic ratios. Scratch testing was used to study the scratch resistance of the hybrid materials and the interfacial strength between the coatings and the substrates. A micro-indentation adhesion test using focused ion beam (FIB) technologies was also used for investigating interfacial strength. The results showed that scratch resistance increases with an increase in the relative amount of organic resin added.

Polyoxometalates are the polyoxoanions of the early transition metals, especially tungsten, molybdenum and vanadium. Although they were first described in the 19th century, their development was slow until modern experimental techniques enabled a greater understanding of their structures and properties. In the last 40 years a large variety of shapes, sizes and compositions have been investigated; functionalisation via covalent grafting of organic groups onto the polyoxometalate clusters is less investigated and provides a method of fine tuning the properties of these materials towards desired applications. Polyoxotungstates (polyoxometalates with tungsten as the metal) are investigated here, those with the Keggin structure being of interest due to the relatively easy formation of lacunary anions which have a highly nucleophilic surface and can react with electrophilic groups to add functionality to the cluster. Organophosphonyl and organosilyl derivatives are prepared with formulae (NR¹₄)₃Hn[XW₁₀O₃₆(R²PO)₂], (NBu₄)₃[XW₉O₃₄(R³SiO)₃(R³Si)], (NBu₄)₃Hn[XW₉O₃₄(tBuSiOH)₃], (NBu₄)₃Hn[XW₉O₃₄(tBuSiO)₃(SiR⁴)], (NBu₄)₃Hn[XW₉O₃₄(R²PO)₂] or (NBu₄)₃Na[SiW₉O₃₄(R²PO)₃] (X = Si or P; R¹ = Bu or Et; R² = Et, H₂C=CH, H₂C=CHCH₂, H₂C=CHC₆H₄, HOOC(CH₂)m (m = 1 or 2) or H₃CCOC₆H₄; R³ = H₂C=CH or H₂C=CHCH₂; R⁴ = R³ or (CH₂)₃Br; n=0 or 1). The structures are confirmed and investigated using multinuclear NMR (¹H, ³¹P and ²⁹Si), IR, MS, EA, single crystal X-ray diffraction and Cyclic Voltammography. The derivatised polyoxotungstate clusters have the potential to take part in further reactions using the organic functionalities to create inorganic-organic hybrid materials which retain the electrochemical properties of the polyoxotungstate units. Examples include the polymerisation of carbon double bonds and condensation reactions of carboxylic acids and amines; both are investigated here. Radical polymerisation is successful in creating polymeric materials, either through single reaction of the polyoxotungstate cluster or a co-polymerisation reaction with a second co-monomer. Reaction with amines did not proceed as expected, instead one of the RPO groups was removed from the cluster, producing a new set of singly derivatised clusters, [SiW₁₀O₃₆(R²PO)]⁶⁻ from [SiW₁₀O₃₆(R²PO)₂]⁴⁻. These create potential for a product with asymmetrically functionised polyoxotungstates containing a mixture of R groups [SiW₁₀O₃₆(R²PO)(R²bPO)]⁴⁻, thus providing greater control over the organic functionality on the cluster and increasing the number of potential derivatives available.

The prepaparation of amorphous, homogeneous blends of zwitterionic polymers and transition metal salts was investigated. Homogeneous miscibility was achieved in many cases up to equimolar amounts of salt, depending on the anion and cation chosen. Various analytical techniques point to a solid state solution of the inorganic ions in the polymer matrix.

Efterfrågan på bättre och mer hållbart material ökar. Mer effektivt material kommer att behövas för att möta den ökande, globala efterfrågan. Hybrida organiska-oorganiska material är en typ av material som har varit av stort intresse nyligen, och kan beskrivas som en typ av material som består av både organiska och oorganiska komponenter. Denna avhandling har fokuserat på hybrida organiska-oorganiska material inspirerade av den klassiska perovskitstrukturen ABX3, där komponent A är en organisk katjon, komponent B är en divalent metalkatjon och komponent X är en anjon. Hybrida organiska-oorganiska material som är utgår från den klassiska perovskitstrukturen kan ha olika funktionella egenskaper och en bred variation av tänkbara applikationer. Några exempel på dessa egenskaper och möjliga applikationer inkluderar god fotokonduktivitet för solceller, utmärkt emissionsegenskaper för ljusdioder och justerbara dielektriska egenskaper för elektroniska växlar och sensorer.  De fysiska egenskaperna av det hybrida organiska-oorganiska materialet beror på kristallstrukturen av materialet, som i sig bestäms av valet av komponenter. På grund av de många möjligheter av organiska och oorganiska komponenter så finns det möjlighet att syntetisera helt nya hybrida organiska-oorganiska föreningar som kan ha nya eller förbättrade fysiska egenskaper.  Nuvarande hybrida organiska-oorganiska material som utgår från perovskitstrukturen använder huvudsakligen bly som divalent metalkatjon, och det beror på att den ger den bästa funktionella effekten. Blys toxicitet är dock en stor nackdel för nuvarande blybaserade hybrid oorganiska material. Möjligheten att ersätta bly med en annan divalent metall har undersökts under detta projekt. I denna avhandling så har den organiska katjonen cyclohexylammonium (CHA) varit i fokus som den organiska komponenten. Målet med detta examensarbete var att designa, syntetisera och karakterisera nytt hybrid organisk-oorganiskt material. De hybrida organiska-oorganiska föreningarna CHAZnBr3 och (CHA)2ZnBr4 syntetiserades för den första gången, så vitt författaren vet, och kommer vara i fokus i denna avhandling. De två nya hybrida organiska-oorganiska föreningarna blev strukturellt karakteriserade med X-ray Diffraction (XRD) och termiskt karakteriserade med Thermal Gravimetric Analysis (TGA) och Differential Scanning Calorimetry (DSC).  Den första föreningen, CHAZnBr3, kunde bestämmas att vara ortorombisk vid 298 K. Föreningen bestämdes vara termisk stabil upp till 490 K, och genomgår en fasövergång vid 445 K. Den andra föreningen, (CHA)2ZnBr4, kunde inte bestämmas strukturellt vid varken 100 K eller 298 K. Föreningen bestämdes vara termisk stabil upp till 490 K, och genomgår en fasövergång vid 230 K. Ytterligare karakterisering krävs för att bättre förstå egenskaperna hos dessa föreningar och deras möjliga användningsområden.
The demand for better and more sustainable material is increasing. More efficient materials will be needed to meet the growing global need. Hybrid organic-inorganic materials are one type of materials that have been of great interest recently, which can be described as a class of materials that mix organic and inorganic components. This thesis focused on hybrid organic-inorganic materials inspired by the classical perovskite crystal structure ABX3, where component A is an organic cation, component B is a divalent metal cation and component X is an anion. Hybrid organic-inorganic materials based on the classical perovskite structure may have various functional properties and may have a broad range of potential applications. Some examples of those properties as well as some and possible applications include good photoconductivity and power conversion efficiency for photovoltaic devices, excellent emission properties for light emitting diodes and tunable dielectric properties for electronic switches and sensors.  The physical properties of the hybrid organic-inorganic material are determined by the crystal structure of the material, which in turn will be decided by the choice of components. With the many possible choices for organic and inorganic components, there is an opportunity to synthesize completely new hybrid organic-inorganic compounds that may display new or superior physical properties. Current hybrid organic-inorganic materials based on the perovskite crystal structure mainly use lead as the divalent metal, since it currently gives the best performance. The toxicity of lead is a major drawback for current lead-based hybrid organic-inorganic materials. The possibility to replace lead with another divalent metal has been explored during this project. For this thesis, the organic cation cyclohexylammonium (CHA) has been of focus as the organic component. The aim of this thesis was to design, synthesize and characterize novel hybrid organic-inorganic compounds. The hybrid organic-inorganic compounds CHAZnBr3 and (CHA)2ZnBr4 were synthesized for the first time, to the best of our knowledge, and will be the focus of this thesis. The two new hybrid organic-inorganic compounds were structurally characterized by X-ray Diffraction (XRD) and thermally characterized by Thermal Gravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC).  The first compound, CHAZnBr3, could be determined to be orthorhombic at 298 K. The compound was found to be thermally stable up 490 K, and to undergo a phase transition at 445 K.  The second compound, (CHA)2ZnBr4, could not be fully structurally solved at either 100 K or 298 K. The compound was found to be thermally stable up to 490 K, and to undergo a phase transition at 230 K.  Further characterization will be needed to better understand the properties of these two compounds and their possible applications.

Solution-processable high refractive index materials are of immense interest for the production of optoelectronic devices, offering the prospect of high throughput, low cost and large area fabrication. In this thesis the optical characterisation of a relatively new type of optical material: the organic/inorganic molecular hybrid is presented. This molecular hybrid uses amorphous titanium oxide hydrates to cross-link polyvinyl alcohol (PVA) and in doing so enables the production of highly transparent thin film coatings with inorganic loadings approaching 100\%. The refractive index of the hybrid material is determined by probing Fabry-Perot oscillations in the transmittance spectra of thin films. This simultaneously demonstrates the high indices, low optical loss and excellent film quality possible for the hybrid. The refractive index is found to be tunable between 1.5 and 1.8 by adjusting the relative content of titanium. However, a simple thermal annealing process is shown to allow indices above 2, without compromising the transparency of the material. The index increase on thermal annealing is explained as the result of the large contraction that also occurs. The hybrid material is then used to fabricate several planar photonic structures. The first is a distributed Bragg reflector, in which the hybrid is deposited sequentially with a commercially available low index fluorinated polymer. The resulting structures have a high reflectance band that is controlled simply by the thicknesses of the high and low index layers. The DBRs demonstrate not only the excellent control of refractive index for the hybrid but also the ability to control layer thickness on the nanometre scale using dip coating. Infrared DBRs that are highly transparent in the visible are also fabricated as a possible application of the hybrid material system for heat management of glass clad buildings. Anti-reflective coatings are also demonstrated that remove 87\% of the reflectance from glass. This is achieved using a symmetrical bi-layer design, again dip cast from solution. Finally, all solution-processed optical microcavities are produced using the hybrid material. First, a simple defect is inserted into a DBR stack to induce a peak in transmittance inside the stop-band. This is then extended to include an emissive material: a perylene derivative, that is coupled to the cavity mode in order to alter its emission characteristics. This, to the best knowledge of the author, is the first demonstration of coupling in a solution-processed optical microcavity.

In this PhD thesis, different types of hybrid organic-inorganic materials were studied as solid sorbents for the carbon dioxide capture, in order to give additional hints to the comprehension of phenomena playing an important role in CO2 adsorption processes. In the first part, hybrid organic-inorganic SBA-15 silicas functionalized with variable amount of amino groups were studied aiming to evaluate the influence of the different basic species on CO2 capture ability. Afterwards, it was decided to study the influence of siliceous support properties on the adsorption process. For this purpose, silica-based materials with different structure, morphology and particle size were selected and tested in the same experimental conditions, aiming to understand the effect of their physico-chemical properties on the CO2 adsorption. On one side MCM-41 silica-based materials with different particle diameter, passing from micrometric to nanometric scale, were considered, in order to study the size effect of the support on the adsorption properties. Furthermore, the effect of the porosity was evaluated by using as adsorbent a non-porous material (Stöber silica) and comparing the obtained results with those of MCM-41-based materials. Finally, the possible use of silica-based materials as catalyst for the carbon dioxide transformation into more useful products was studied. In particular, heterogeneous Cu-based catalyst supported on SiO2 have been studied as for the promotion of hydrogenation reaction of CO2 to formic acid.

Adsorption processes are widely used for the storage and separation of gases in many industrial and environmental applications. The performance of the process depends strongly on the adsorbent and its interaction with the gases. Therefore, the idea of tailoring the adsorbent to the application by adapting the pore size and/or the chemical composition is very attractive. This work focuses on two groups of customizable hybrid materials: Firstly, in crystalline metal-organic frameworks (MOFs) the chemical and structural properties can be modified by changing the metal-oxide corner or the organic linker. Secondly, periodic mesoporous silica materials can be prepared with different pore sizes and geometries depending on the surfactant and its concentration and additionally modified with organic surface groups. The adsorption behaviour of the materials can be predicted by molecular simulation and thus the influence of modifications can be studied without the need of synthesising the material. For MOFs, the coordinates of the atoms can be obtained from XRD measurements. The quality of the predicted adsorption results was investigated for pure gas (methane, ethane, propane, nitrogen and carbon dioxide) and gas mixture (methane – carbon dioxide) adsorption on the metal-organic framework CuBTC. The comparison showed a good agreement between experimental and simulated results especially at low pressures. In order to create atomistic models for the mesoporous silica structures that are amorphous on the atomistic level, two existing simulation methods to model MCM-41-type materials were combined: micellar structures from coarse grained simulations that capture the phase separation in the surfactant/silica/solvent mixtures were used as input in kinetic Monte Carlo simulation that created the pore model on the atomistic level. The model created with this new methodology showed similar adsorption behaviour compared with a model created only with the kMC method using an ideal geometrical structure as micelle. The influence of modifications of the MOF structures (exchange of metal, linker length/composition and catenation) was investigated by Grand Canonical Monte Carlo simulations for hydrogen adsorption at low temperature and temperature controlled desorption. The peaks in the desorption spectra could be related to steps in the adsorption isotherms at 20 K.

Thesis (Ph. D.)--Dept. of Chemistry and School of Pharmacy. University of Missouri--Kansas City, 2005.
"A dissertation in chemistry and pharmaceutical sciences." Advisor: Zhonghua Peng. Typescript. Vita. Description based on contents viewed June 26, 2006; title from "catalog record" of the print edition. Includes bibliographical references (leaves 173-190). Online version of the print edition.

[EN] The present PhD thesis is centred in the design (using concepts of supramolecular chemistry), synthesis and characterization of different hybrid organic-inorganic materials for boron removal from aqueous media. The interaction between boron and organic groups, polyols, used in the development of these new adsorbents is also studied. In the first part of the thesis it is presented a brief review of supramolecular chemistry concepts, chemistry of boron and also the main methods for boron removal (first chapter) and, also, the objectives of this thesis (second chapter). The third chapter exposes the results obtained by using a ceramic foam as macroscopic support for active materials for boron removal. This support is previously "impregnated" with an inorganic silica mesoporous material (UVM-7) and, in a second step, it is functionalized with an organic group with high boron affinity (gluconamide). This organic group, which works as an adsorbent, remains anchored to a macroscopic support, which will facilitate the use of these materials in industrial applications. Once the material is synthetized their boron adsorption and elimination abailability in aqueous media is studied and its ulterior reutilization. The fourth chapter of the PhD thesis is focused on the preparation of low cost materials for boron adsorption from water. In first place, it is used, as inorganic scaffolding, UVM-7 material, a mesoporous silica phase with a bimodal pore system. This material has a high boron adsorption capacity after its functionalization with the polyalcohol (as it is shown in the previous chapter) nevertheless, the reagents used in the synthesis tetraethylorthosilicate, as silica source, and hexadecyltrimethylammonium bromide, as templating agent are so expensive that they induce a high cost of final materials. In this chapter is presented as an alternative another materials which are able to perform as inorganic scaffolds: UVM-11 (surfactant-free mesoporous material), two silica xerogels with pores within the mesoporous range and comercial high surface area silica fume were prepared. Once all the materials are synthetized they are functionalized with gluconamides which are the active compounds for boron adsorption. Finally, a comparative study of the boron adsorption capacities in water is carried out. Low cost materials present comparable boron removal to those of higher cost and comercially abailable materials. Finally, in the fith chapter of this PhD thesis, the adsorption mechanism of boron on the active materials (based on UVM-7 as inorganic support) is studied using solid Nuclear Magnetic Resonance measures of 11B and 13C and using techniques as Magic Angle Sppining, crossed polarization and heteronuclear polarization disacoplament. To do that, a hybrid material composed by UVM-7 matrix grafted with gluconamide is prepared and then the solid is put in contact with different boron quantities. Final solids are characterized through 13C and 11B NMR, showing the formation of boronesters between gluconamide diol groups and boron adsorbed. When low boron concentration is used, bisquelate complexes are formed (B:glucosa = 1:2), however with higher concentrations monoquelate complexes are formed (B:glucosa = 1:1). This work was carried out in collaboration with the research group of "sol-gel materials and NMR", appertaining to the center of "Chimie de la matière condensée de Paris" of the "Université Pierre et Marie Curie".
[ES] La presente tesis doctoral está dedicada al diseño (empleando conceptos de química supramolecular), síntesis y caracterización de diferentes materiales híbridos orgánico-inorgánicos para la eliminación de boro en medios acuosos. También se ha procedido a estudiar detalladamente la interacción del boro con las agrupaciones orgánicas, polialcoholes, empleadas en el desarrollo de estos nuevos adsorbentes. En la primera parte de la tesis de presenta una introducción en la que se revisa los conceptos de química supramolecular, química del boro y los principales métodos de eliminación de boro (primer capítulo) y, también, se exponen los objetivos de la tesis (segundo capítulo). Ya en el tercer capítulo se exponen los resultados obtenidos empleando una esponja cerámica como soporte macroscópico para los materiales activos frente a la eliminación de boro. Este soporte se "impregnan" previamente con un material inorgánico silíceo mesoporoso (UVM-7) y, en una fase posterior, se funcionaliza con un grupo orgánico con alta afinidad hacia el boro (gluconamida). El grupo orgánico que funcionará como adsorbente queda así anclado a un soporte de tamaño macroscópico que facilitará la aplicación de estos materiales a gran escala. Una vez preparado y caracterizado se estudió la capacidad del material para adsorber y eliminar boro de medios acuosos y su posterior reutilización. En el cuarto capítulo de la tesis doctoral se aborda la preparación de materiales adsorbentes de bajo coste económico para la eliminación de boro en medios acuosos. En primer lugar se emplea, como soporte inorgánico, UVM-7 una sílice mesoporosa con un sistema bimodal de poros. Este material tiene una capacidad de adsorción de boro muy elevada una vez funcionalizado con el correspondiente polialcohol (tal y como se expone en el capítulo anterior) sin embargo los reactivos para su síntesis tetraetilortosilicato como fuente de sílice y bromuro de cetiltrimetilamonio como agente director de estructura son muy caros con lo que el material final presenta un elevado coste. En este capítulo se presenta como alternativa otros materiales que puedan actuar como soportes inorgánicos: UVM-11, material mesoporoso que no requiere de agente director de estructura en su síntesis, dos xerogeles con poros en el rango meso y una sílice comercial nanoparticulada de elevada superficie específica. Una vez sintetizados y caracterizados los cinco soportes se funcionalizaron con gluconamidas, que son los componentes activos frente a la adsorción de boro. Finalmente, se realiza un estudio comparativo de la capacidad de eliminación de boro de los cinco materiales preparados. Los materiales de bajo coste estudiados presentan una capacidad de eliminación de boro comparable a los materiales de mayor coste y a los materiales comercialmente disponibles. Por último, en el capítulo cinco de esta tesis doctoral, se aborda el estudio del mecanismo de adsorción del boro en los materiales activos preparados (basados en UVM-7 como soporte inorgánico) mediante medidas de resonancia magnética nuclear de sólidos, tanto de 13C como de 11B empleando las técnicas de rotación en ángulo mágico, polarización cruzada, y el desacoplamiento dipolar heteronuclear. Para ello se prepara un material híbrido formado por una matriz de UVM-7 funcionalizada con gluconamidas y este sólido se pone en contacto con diferentes cantidades de boro. Los sólidos finales se caracterizan mediante RMN de 13C y de 11B, observándose la formación de boroesteres entre los grupos diol de las gluconamidas ancladas y el boro adsorbido. Cuando la concentración de boro empleada es baja se forman complejos bisquelados (B:glucosa = 1:2) mientras que a concentraciones altas empiezan a formarse complejos monoquelados (B:glucosa = 1:1). Este trabajo se llevó a cabo en colaboración con el grupo de investigación de "Materiales sol-gel y RMN", perteneciente al centro "Chimie de la matiè
[CAT] La present tesi doctoral està dedicada al disseny (empleant conceptes de química supramolecular), síntesi i caracterització de diferents materials híbrids orgànico-inorgànics per a la el¿liminació de bor en medi aquòs. També s'ha precedit a estudiar detalladament la interacció del bor amb les agrupacions orgàniques, polialcohols, empreats en el desenvolupament d'aquestos nous adsorbents. En la primera part de la tesi es presenta una introducció en la que es revisen els conceptes de química supramolecular, química del bor i els principals mètodes de el¿liminació de bor (primer capítol) i, també, s'exposen els objectius de la tesi (segon capítol). Ja en el tercer capítol s'exposen els resultats obtinguts empreant una esponja ceràmica com a suport macroscòpic per als materials actius front a l'el¿liminació del bor. Aquest suport s'impregna prèviament amb un material inorgànic de sílice mesoporós (UVM-7) i, en una següent fase, es funcionalitza amb un grup orgànic amb alta afinitat cap al bor (gluconamida). El grup orgànic que funcionarà com a adsorbent queda aixina anclat a un suport de tamany macroscòpic que facil¿litarà l'aplicació d'aquestos materials a gran escala. Una vegada preparat i caracteritzat s'estudia la capacitat del material per a adsorber i el¿liminar bor en medi aquós i la seua posterior reutilització. Al quart capítol de la tesi doctoral s'aborda la preparació de materials adsorbents de baix cost econòmic per a l'eliminació de bor en medi aquòs. En primer lloc, s'empra, com a suport inorgànic, UVM-7 una sílice mesoporosa amb un sistema bimodal de porus. Aquest material té una capacitat d'adsorció molt elevadadeprés de la seua funcionalització amb el corresponent polialcohol (tal i com s'exposa al capítol anterior), no obstant això els reactius que s'utilitzen per a la seua síntesi tetraetilortosilicat com a font de sílice i bromur de cetiltrimetilamoni com agent director d'estructura són molt cars, per tant el material final presenta un elevat cost. En aquest capítol es presenta com alternativa altres materials que puguen actuar com a suports inorgànics: UVM-11, material mesoporòs que no requereix d'agent director d'estructura durant la seua síntesi, dos xerogels en porus en el rang meso i una sílice comercial nanoparticulada amb elevada superficie específica. Una vegada sintetitzats i caracteritzats els cinc suports es funcionalitzen en gluconamides, que són els components actius front a la adsorció de bor. Finalment, es realitza un estudi comparatiu de la capacitat d'el¿liminació de bor dels cinc materials preparats. Els materials de baix cost estudiats presenten una capacitat de eliminació de bor semblant als materials de major cost i als materials comercialment disponibles. Per últim, al capítol cinc d'aquesta tesi doctoral, s'aborda l'estudi del mecanisme d'adsorció de bor als materials actius preparats (basats en UVM-7 com a suport inorgànic) mitjançant medides de resonància magnética nuclear de sólids, tant de 13C com de 11B emprant tècniques de rotació en àngul màgic, polarització creuada, i el desacoplament dipolar heteronuclear. Per a ell es prepara un material híbrid format per una matriu de UVM-7 funcionalitzada amb gluconamides i aquest sòlid es posa en contacte amb diferents quantitats de bor. Els sòlids finals es caracteritzen mitjançant RMN de 13C i de 11B observant-se la formació de borésters entre els grups diol de les gluconamides anclades i el bor adsorbit. Quan la concentració de bor emprada és baixa es formen complexos bisquelats (B:glucosa = 1:2) mentre que a concentracions més altes comencen a formar-se complexos monoquelats (B:glucosa = 1:1). Aquest treball és va realitzar ne col¿laboració amb el grup d'investigació de "Materials sol-gel i RMN", perteneixent al centre "Chimie de la matière condensée de Paris" de la "Université Pierre et Marie Curie".
Sanfeliu Cano, C. (2016). Organic-inorganic hybrid materials for boron removal from aqueous media [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/63277
TESIS

Doutoramento em Física
Luminescent solar concentrators are inexpensive devices that aim to increase the efficiency of photovoltaic cells and promote the urban integration of photovoltaic devices, with unprecedented possibilities of energy harvesting through the façade of buildings, urban furniture or wearable fabrics. Generally, they consist of a transparent matrix coated or doped with active optical centres that absorb the incident solar radiation, which is re-emitted at a specific wavelength and transferred by total internal reflection to the edges where the photovoltaic cells are located. The main objective of this work is the production of luminescent solar concentrators whose optically active layer is based on organic-inorganic hybrid materials doped with europium ions or organic dyes, in particular, Rhodamine 6G and Rhodamine 800. Rhodamine 800, as opposed to europium ions and Rhodamine 6G which emit in the visible range, emits in the near infrared (NIR) range, which is an advantage for crystalline Si-based photovoltaic cells, whose efficiency is greater in the NIR. In this work, although the luminescent solar concentrators with planar geometry are addressed, the main focus is the use cylindrical geometry. The use of this type of geometry allows the effect of concentration to be higher relative to the planar geometry, since the ratio between the exposed area and the area of the edges is increased. The cylindrical geometry is exploited by producing luminescent solar concentrators based on polymer optical fibre (plastic) where the optically active layer is on the outside (as a coating) or inside (as a filling in the hollow core) of the optical fibre. Furthermore, the possibility of increasing the exposed area was also dealt with the production of bundles of luminescent solar concentrators in which the plastic optical fibres are placed side by side and, also, by fabricating luminescent solar concentrators with length in the metre scale.
Os concentradores solares luminescentes são dispositivos de baixo custo que têm como objetivo aumentar a eficiência de células fotovoltaicas e promover a integração de dispositivos fotovoltaicos em elementos do dia-a-dia, tornando possível a captura de energia solar, através da fachada de edifícios, mobiliário urbano ou em têxteis. Geralmente, consistem numa matriz transparente coberta ou dopada com centros óticos ativos, capazes de absorver a radiação solar incidente e reemiti-la com um comprimento de onda específico que será transportada, através de reflexão interna total, para as extremidades da matriz onde se encontra(m) a(s) célula(s) fotovoltaica(s). O principal objetivo deste trabalho consiste na produção de concentradores solares luminescentes cuja camada ótica ativa é baseada em materiais híbridos orgânicos-inorgânicos dopados com iões lantanídeos (európio, Eu3+) ou corantes orgânicos, nomeadamente, Rodamina 6G e Rodamina 800. A Rodamina 800, ao contrário dos iões de európio e da Rodamina 6G que emitem na gama do visível, emite na região espetral do infravermelho próximo (NIR), que se revela uma vantagem quando a célula fotovoltaica em uso é composta de silício cristalino, cuja gama de maior eficiência é no NIR. Neste trabalho, apesar de serem abordados concentradores solares luminescentes com geometria planar, o principal foco é a utilização da geometria cilíndrica. Este tipo de geometria permite que o efeito de concentração seja superior, relativamente à geometria planar, uma vez que a razão entre a área exposta e a área das extremidades é aumentada. A geometria cilíndrica é explorada, através da produção de concentradores solares luminescentes com base em fibra ótica polimérica (plástica) em que a camada ótica ativa se encontra no exterior (como um revestimento) ou no interior (como um preenchimento do núcleo oco). Além disso, a possibilidade de aumentar a área exposta foi, também, abordada com o fabrico de uma matriz de concentradores solares luminescentes colocados lado a lado e, também, com o fabrico de concentradores solares luminescentes na escala do metro.

The acid and base catalyzed simultaneous twin polymerization (STP) of various 2,2′-disubstituted 4H-1,3,2-benzodioxasiline derivatives 2a–d with 2,2′-spirobi[4H-1,3,2-benzodioxasiline] (1) are presented in this paper. The products are nanostructured ternary organic–inorganic hybrid materials consisting of a cross-linked organic polymer, silica and a disubstituted polysiloxane. It can be demonstrated whether and in which extent the copolymerization of the two inorganic fragments of 1 and 2 takes place among the STP and how the molar ratio of the two components determines the structure formation of the resulting hybrid material. Steric and electronic effects of the substituents at the silicon center of 2 on the molecular structure formation and the morphology of the resulting hybrid material were investigated by means of solid state CP MAS 29Si and 13C NMR spectroscopy as well as high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM). The mechanical properties (hardness and Young's modulus) of the hybrid materials were analyzed by means of nanoindentation measurements
Dieser Beitrag ist aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich

Organic and hybrid organic-inorganic photovoltaic (PV) devices have the potential to provide low-cost, large scale renewable energy. Despite the tremendous progress that has been made in this field, device efficiencies remain low. This low efficiency can be partly attributed to the low open-circuit voltages (Voc) generated by organic and hybrid organic-inorganic PV devices. The Voc is critically determined by the energy-level alignment at the interface between the materials forming the device. In this thesis we use first-principles methods to explore the energy-level alignment at the interfaces between the conjugated polymer poly(3-hexylthiophene) (P3HT) and three electron acceptors, zinc oxide (ZnO), gallium arsenide (GaAs) and graphene. We find that Voc reported in the literature for ZnO/P3HT devices is significantly lower than the theoretical maximum and that the interfacial electrostatic dipole plays an important role in the physics underlying the charge transfer at the heterojunction. We note significant charge transfer from the polymer to the semiconductor at GaAs/P3HT interfaces, and use this result to help interpret experimental data. Our findings support the conclusion that charge transferred from P3HT to GaAs nanowires can passivate the surface defect states of the latter and, as a result, account for the observed decrease in photoluminescence lifetimes. Finally, we explore the energy-level alignment at the graphene/P3HT interface and find that Voc reported for experimental devices is in line with the theoretical maximum. The effect of functionalised graphene is also examined, leading to the suggestion that functionalisation might have important consequences for device optimisation.

In the last decades the development of new technologies is requiring new materials with enhanced emissive properties in the solid state to be applied in different fields spanning from OLED to biological applications. Research in this context is historically limited by the observation that luminogens possess better properties in dispersed system than in the condensed phase due to the well-known Aggregation Caused Quencing (ACQ) phenomenon. However, in 2001 Tang and co-workers reported some pioneering works on luminogens displaying opposite properties, being highly emissive in the condensed phase but not in diluted solution, a behaviour named Aggregation Induced Emission (AIE) [1]. Different mechanisms may explain the AIE phenomenon, the most frequent one being the inhibition of molecular motions (vibrations and rotations) which works as nonradiative deactivation channels for the molecule but are somehow locked in the aggregated state. In parallel, strong efforts have been devoted to the search of organic molecules with long-lived excited states that enable exciton migration over long distances for increased production of free charges. Usually, transitions from singlet (short-lived) to triplet (long-lived) states are facilitated by the presence of metals or specific organic moieties (i.e. aromatic aldehyde, heavy halogen atoms, heteroatoms with lone pairs). In addition, since triplet excitons generated in organic molecules are highly sensitive to oxygen and temperature, stringent conditions are required to observe long-lived phosphorescence from pure organic molecules. However, very recently, An et al. reported ultralong phosphorescent emission features in structures of planar organic molecules coupled in H-aggregates, which provide an effective means of stabilizing and protecting triplet excitons formed through intersystem crossing (ISC) [2]. The stabilized excited state, which functions as an energy trap at a lower energy level, may delocalize on several neighbouring molecules, offering suppressed radiative and nonradiative deactivation decay rates in favour of long-lived excited states and room temperature ultralong phosphorescence (RTUP). In this regard, during my research work, I have been involved in the synthesis and characterization of triimidazo[1,2-a:1',2'-c:1'',2''-e][1,3,5]triazine (TT or cyclic triimidazole) and of its derivatives. In fact, TT is an intriguing solid state luminogen characterized by AIE and RTUP properties. Diluted solutions of TT in DCM display weak emission (Ф = 2%) even under inert atmosphere, while crystalline powders (Ф = 30%) show an intense fluorescent emission at 425 nm and an ultralong emission at 520 nm with decay time close to 1 s. This behaviour, in agreement with works by An et al. [2] arises from the formation of H-aggregates in the crystal structure of the compound as revealed by XRD studies [3]. The main goal of my project has been the synthesis and characterization of organic and hybrid inorganicorganic 1. Luo, J.; Xie, Z.; Lam, J. W. Y.; Cheng, L.; Chen, H.; Qiu, C.; Kwok, H. S.; Zhan, X.; Liu, Y.; Zhu, D.; Tang, B. Z., Aggregation-induced emission of 1-methyl-1,2,3,4,5-pentaphenylsilole. Chemical Communications 2001, (18), 1740-1741. 2. An, Z.; Zheng, C.; Tao, Y.; Chen, R.; Shi, H.; Chen, T.; Wang, Z.; Li, H.; Deng, R.; Liu, X.; Huang, W., Stabilizing triplet excited states for ultralong organic phosphorescence. Nature Materials 2015, 14 (7), 685-690. 3. Lucenti, E.; Forni, A.; Botta, C.; Carlucci, L.; Giannini, C.; Marinotto, D.; Previtali, A.; Righetto, S.; Cariati, E., H-Aggregates Granting Crystallization-Induced Emissive Behavior and Ultralong Phosphorescence from a Pure Organic Molecule. The Journal of Physical Chemistry Letters 2017, 8 (8), 1894-1898.

The aim of this PhD thesis is to undertake a comprehensive research to study the optical, electrical, surface electronic and morphologic properties, formulation and surface modification of solution processable organic-inorganic hybrid transparent electrodes as well as their applications in optoelectronic devices. In this study, MoO3 nanoparticles and graphene oxide (GO) nanosheets were incorporated into the poly(3,4-ethylenedioxythiophene) -poly(styrenesulfonate) (PEDOT:PSS) layer forming a hybrid anode interfacial layer (AIL) and subsequently a hybrid transparent electrode of AIL/silver nanowires (AgNWs), significantly improved charge injection in CdSe/ZnS-based quantum dot-light emitting diodes (QD-LEDs) and charge collection in bulk heterojunction (BHJ) organic solar cells (OSCs). The effect of oxidation behavior and charge transfer between PEDOT and MoO3, as well as PEDOT and GO, on the enhancement in conductivity of hybrid PEDOT:PSS-MoO3 and PEDOT:PSS-GO AILs was investigated systematically. The presence of a PEDOT:PSS-MoO3 AIL promotes a good interfacial contact between the hole transporting layer (HTL) and the solution-processed hybrid transparent electrode for efficient operation of QD-LEDs. This work reveals that the use of the hybrid PEDOT:PSS-MoO3 AIL benefits the performance of QD-LEDs in two ways: (1) to assist in efficient hole injection, thereby improving luminous efficiency of QD-LEDs, and (2) to improve electron-hole current balance and suppression of interfacial defects at the QD/electrode interface. The surface wettability of the PEDOT:PSS-MoO3 AIL was controlled successfully for making a good contact between the HTL and the AgNWs, enabling efficient charge injection or charge collection, and thereby improvement in the device performance. The effect of PEDOT:PSS-GO AIL on the performance of transparent QD-LEDs was also analyzed. The maximum brightness of the transparent QD-LEDs, made with a solution-processed hybrid top transparent electrode of PEDOT:PSS-GO/AgNWs, is 3633 cd/m2 at 15 V, comparable to that of a structurally identical control QD-LED made with an evaporated Ag electrode, with a brightness of 4218 cd/m2 operated under the same condition. The change in the hydrophobicity of the PEDOT:PSS-GO AIL, e.g., from the hydrophobic to hydrophilic characteristics, was observed. The interaction between PEDOT and GO nanosheets induces the transition between benzoid-quinoid structures, contributing to the enhanced charge carrier transport via the PEDOT:PSS-GO AIL. The energy level alignment at the HTL/electrode interface and the excellent electrical conductivity of PEDOT:PSS- GO/AgNWs transparent electrode result in an obvious improvement in the performance of QD-LEDs. Transparent QD-LEDs also demonstrated remarkable efficiency via cathode interfacial engineering. Two cathode interfacial modifications include incorporating (1) a hybrid bathophenanthroline (Bphen):Cs2CO3-based electron transporting buffer layer (EBL) and (2) a conjugate polymer of poly[(9,9-bis(3'-((N,N-dimethyl)-N-ethylammonium)-propyl)-2,7- fluorene)-alt-2,7-(9,9-dioctylfluorene)] (PFN-Br)-based EBL. The approach of n-doping effect in the BPhen:Cs2CO3 EBL not only modifies the surface electronic properties of the ZnO electron transporting layer (ETL) but also improves the electron injection at the QD/cathode interface. The n-doping mechanism in the Bphen:Cs2CO3 EBL was investigated. PFN-Br EBL has also been employed to tune the surface work function of ZnO ETL. It was observed that the ZnO/PFN-Br formed an interfacial dipole at the ETL/QD interface, which is suitable for efficient electron injection in the transparent QD-LEDs. In order to improve electron-hole current balance, a GO/MoO3-based multilayer AIL was adopted facilitating efficient charge transfer through improved energy level alignment at the HTL/hybrid electrode interface. Photoelectron spectroscopy revealed tuned surface work function with reduced interfacial barrier for efficient hole injection in transparent QD-LEDs. In these devices, the cathode and anode interfacial modifications have been optimized and studied. This study was also extended to investigate the effect of the organic-inorganic hybrid electrode on performance enhancement of all solution processable organic solar cells (OSCs). The reduction in series resistance and increase in shunt resistance of solution-processed OSCs originated from improved contact selectivity as well as enhanced charge collection efficiency. These properties are reflected in the significantly improved fill factor and short-circuit photocurrent density for the all solution-processed OSCs. Enhanced charge collection at the BHJ/electrode interfaces and improved process compatibility are mainly responsible for efficiency improvement in the cells. The outcomes of this work would allow further advances in device performance. This research also highlights the need to explore interfacial electronic properties and reduce energetic barrier at BHJ/electrode interfaces in fully solution-processed OSCs through photoelectron spectroscopy measurements. The results of this research demonstrate that the solution processable organic-inorganic hybrid transparent electrode developed in this work is beneficial for application in fully solution-processed optoelectronic devices.

Hybrid organic/inorganic photovoltaics can overcome many traditional shortcomings of organic photovoltaics, including recombination due to short exciton diffusion length scales, incomplete or tortuous charge transport pathways, and low charge mobility. In this work, aligned pore arrays are electrochemically etched into GaN films, and the semiconducting polymer polyhexylthiophene (P3HT) is intruded into these porous films. This hybrid device uses the polymer as the photoactive phase, electron donor, and hole transport medium, and the GaN as the electron acceptor and electron transport medium. Not only does the nanoporous geometry result in ultrafast charge transfer between the P3HT and the GaN, but a nanoconfined geometry can also drastically enhance charge mobility in the polymer by orienting the polymer alignment such that the fast charge transport direction is oriented vertically.

Optimal etching parameters are found in various etchants to produce an aligned morphology, and a method to remove the low-porosity overlayer via UV-assisted etching is described. Additionally, the first reported pore formation in GaN using a neutral etching solution is demonstrated, opening up the possibility of safe and environmentally-friendly etching of GaN, in contrast to traditional methods that use extremely toxic hydrofluoric acid.

Multiple methods to introduce polymer into the pores are described, and it is shown that hot pressing can achieve favorable polymer alignment. Ultrafast charge transport is demonstrated between the confined polymer and the GaN template by time-resolved terahertz spectroscopy. This geometry of an aligned nanoporous template surrounding an organic semiconductor is proposed as a general and beneficial strategy to improve performance of organic solar cells.

The work presented in this dissertation suggests novel design of chemical plasmonic sensors which have been developed based on Localized Surface Plasmon Resonance (LSPR), and Surface-enhanced Raman scattering (SERS) phenomena. The goal of the study is to understand the SERS phenomena for 3D hybrid (organic/inorganic) templates and to design of the templates for trace-level detection of selected chemical analytes relevant to liquid explosives and hazardous chemicals. The key design criteria for the development of the SERS templates are utilizing selective polymeric nanocoatings within cylindrical nanopores for promoting selective adsorption of chemical analyte molecules, maximizing specific surface area, and optimizing concentration of hot spots with efficient light interaction inside nanochannels. The organic/inorganic hybrid templates are optimized through a comprehensive understanding of the LSPR properties of the gold nanoparticles, gold nanorods, interaction of light with highly porous alumina template, and the choice of physical and chemical attributes of the selective coating. Furthermore, novel method to assemble silver nanoparticles in 3D as the active SERS-active substrate has been demonstrated by uniform, in situ growth of silver nanoparticles from electroless deposited silver seeds excluding any adhesive polymer layer on template. This approach can be the optimal for SERS sensing applications because it is not necessary to separate the Raman bands of the polyelectrolyte binding layer from those of the desired analyte. The fabrication method is an efficient, simple and fast way to assemble nanoparticles into 3D nanostructures. Addressable Raman markers from silver nanowire crossbars with silver nanoparticles are also introduced and studied. Assembly of silver nanowire crossbar structure is achieved by simple, double-step capillary transfer lithography. The on/off SERS properties can be observed on silver nanowire crossbars with silver nanoparticles depending on the exact location and orientation of decorated silver nanoparticles nearby silver nanowire crossbars. As an alternative approach for the template-assisted nanostructure design, porous alumina membrane (PAM) can be utilized as a sacrificial template for the fabrication of the nanotube structure. The study seeks to investigate the design aspects of polymeric/inorganic hybrid nanotube structures with plasmonic properties, which can be dynamically tuned by external stimuli such as pH. This research suggests several different organic/inorganic nanostructure assemblies by various template-assisted techniques. The polymeric/inorganic hybrid nanostructures including SERS property, pH responsive characteristics, and large surface area will enable us to understand and design the novel chemical plasmonic sensors.

Le travail de recherche de cette thèse consiste en le développement de nouveaux matériaux hybrides organiques-inorganiques pour des applications en nanotechnologie, nanomédicine et diagnostic. Dans ce contexte, des cristaux poreux de zéolite-L ont été utilisé comme nano-vecteur pour faire de la transfection d’ADN et d’ANP, en combinaison avec le relargage de molécules hôtes placées dans les pores. Des nanoparticules de silice mesoporeuses multifonctionnelles ont été utilisées pour traiter le glioblastome, en combinant la thérapie génique avec l’administration durable d’un principe actif. Des nano-coquilles hybrides biodégradables ont été encore développés pour encapsuler des protéines et les relâcher dans les cellules vivantes. Dans le domaine de la détection d’acides nucléiques, des fibres optiques à cristal photonique, fonctionnalisées avec des sondes d’ANP, ont été exploitées comme plateformes optiques pour faire de la détection ultra-sensible d’oligonucléotides ou d’ADN génomique. Enfin, la squelette de l’ANP a été modifié à créer des sondes fluorescentes pour reconnaître et détecter la présence des séquences cibles spécifiques
The research work presented throughout this thesis focuses on the development of novel organic-inorganichybrid materials for applications in nanotechnology, nanomedicine and diagnostics. In such a context, porous zeolite-L crystals have been used as nanocarriers to deliver either DNA or PNA in live cells, in combination with the release of guest molecules placed into the pores. Multifunctional mesoporous silica nanoparticles have been designed to treat glioblastoma, combining gene therapy with the sustained delivery of a chemotherapy agent. Biodegradable hybrid nano-shells have been furthermore created to encapsulate proteins and release them in living cells upon degradation of the outer structure in reductive environment. In the field of nucleic acid detection, photonic crystal fibers, functionalized with specific PNA probes, have been exploited as optical sensing devices to perform ultra-sensitive detection of DNA oligonucleotides or genomic DNA. Eventually, the PNA backbone has served as scaffold to synthesize fluorescent switching probes able to recognize and to detect the presence of specific target sequences

The present investigation is concerned with the processing and characterization of sol-gel derived Polyceram materials. Polycerams, a new class of multi-functional materials, are organic-inorganic composite materials where the components are combined at or near the molecular level. In this dissertation, particular emphasis is attributed to the synthesis, processing and characterization of thin films of Polycerams. Numerous optical characterization techniques were performed to study the passive properties of Polycerams, including index of refraction, optical attenuation, UV transmission and surface embossing. Dielectric waveguides of superior optical quality were obtained and Polycerams proved to be surface patternable with near-perfect shape replication abilities. The above properties are discussed in conjunction with a scattering model which explains the structural homogeneity of Polycerams. Optical losses below 0.15 dB/cm and the simple fabrication of channel waveguides and lenses via surface embossing render Polycerams highly suitable candidates for today's integrated optics technology.

The aim of this project was to prepare a series of silica materials based on sol-gel processing of alkoxysilanes using glucose and glycerol as templates for potential applications in membrane design for pervaporation. The materials were characterized using structural and dynamic techniques to gain information about the effect of the templates on the formation of micro- and mesoporous silicates. The interaction between templates and silica matrices were investigated using FTIR, Raman Spectroscopy, Solid State NMR Spectroscopy, Physisorption and SEM. Close contact between templates and silica networks was observed by NMR cross polarization studies. The chemistry was then extended to prepare hybrid organic-inorganic silica materials by introducing organic ligands, with glycerol as a template to control the porosity of the hybrid materials. By varying the ligand as well as the template, the physical properties of the gel can be controlled. Composites of hydroxypropylcellulose, HPC, and silica were also prepared and characterized. There was no phase separation during sol-gel processing suggesting HPC was dispersed homogenously in the silica matrices. This was also confirmed by solid state NMR. Temperature dependence showed some indications of conformational change in the HPC within the silicate, above 308K. The transport properties of the hybrid materials were observed by monitoring the diffusion behaviour of water and several selected solvents using Pulsed Field Gradient NMR. The self-diffusion of water and the organic solvents in the hybrid silica materials were two to three orders of magnitude smaller than in the liquid bulk suggesting restricted diffusion at the pore surface. The effect of surface polarity also contributed to water and solvents diffusivities. The temperature dependence of diffusion was useful to derive the activation energy whereas the dependence on NMR observation time provided information on both tortuosity and pore connectivity of the hybrid silica materials. The hybrid silica membranes were prepared by spin coating of polymeric silica sol on top of a macroporous alumina support after being occluded by colloidal silica. It was then used for pervaporation of water ethanol mixtures. The results implied that separation factor increased as the temperature increased. However permeate fluxes were less affected.

Computational modelling of porous hybrid organic-inorganic materials is a challenging task. The dual nature and flexibility of frameworks require the delicate description of systems. In addition, the absence of reliable force-fields and the size of systems makes the density functional theory (DFT) the best choice. The poor description of long-range dispersion interactions, a crucial deficiency of DFT, has been circumvented by introducing the dispersion correction schemes. Zeolitic imidazolate frameworks (ZIF), extended analogues of inorganic zeolites by topological similarity, are the focal point of this thesis. Their prospective applications in gas adsorption/separation and catalysis are driving the search of new not-yet-syntesised structures and methods to tune their properties. A set of new hypothetical ZIF has been explored, including lightweight LiB-based frameworks. To establish structure-property relationship, the impact of topologies and linker has been analysed. It has been revealed the crucial role of linker-linker interaction and packing for the thermodynamics stability of frameworks. Furthermore, the mechanical properties of ZIFs have been explored. Close collaboration with experimentalist groups has allowed the cross-linked analysis and rationalization of the observed of phenomena. Finally, an empirical force-field fitting protocol from ab initio data has been improved. The idea is to exploit the redundant internal coordinates in fitting as it makes the problem more linear, but an existing code was able to handle non-periodic models only. The periodicity has been implemented to allow fitting force-field for material, which could not be partitioned into non-periodic models, including ZIFs. The new protocol has been tested with several systems.

Doctor of Philosophy
Department of Chemistry
Eric A. Maatta
The thesis focuses on the design and synthesis of novel organoimido delivery reagents capable of forming bimetallic polyoxometalate (POM) hybrids, and their use in the assembly of bimetallic hexamolybdate derivatives. These delivery reagents have been designed thoughtfully and separate organic moieties have been selected for coordinating to both the POM cluster and the second metal atom. A series of three ligands [4-aminopiperidine, 4-(4-aminophenyl) piperazine, and 4-(4-aminophenyl) piperidine] were selected and used to synthesize the dithiocarbamate metal-coordinating ligands, which in turn were used for preparing the corresponding metal (M = Cr, Mn, Fe, Co, Ni, Cu, Zn, Ag) complexes. All the complexes were characterized by infrared spectroscopy (IR). Reported routes were followed for the covalent grafting of these metal complexes onto hexamolybdate. But, the poor solubility of these metal complexes was found to be a major stumbling block in our endeavors to synthesize the dithiocarbamate based polyoxometalate hybrids. The observed poor solubility of metal dithiocarbamate complexes was overcome by synthesizing [potassium(I) tris(3,5-diphenylpyrazole)borate] and [potassium(I) tris(3,5-dimethylpyrazole)borate] via thermal dehydrogenative condensation between tetrahydroborate and the respective pyrazole molecule. A series of corresponding transition metal (M = Co, Ni, Cu, Mn) complexes of tris(3,5-diphenylpyrazole)borate and tris(3,5-dimethylpyrazole)borate were synthesized, and characterized by IR and UV-visible spectroscopy, and single crystal X-ray diffraction. The single crystal structure of [manganese(II) (tris(3,5-dimethylpyrazole)borate)2] turned out to an outlier as it displayed the formation of a bis-complex, thus having no substitutable anion for further reaction with dithiocarbamates. Thereafter, a series of metal dithiocarbamate complexes of these [hydrotris(pyrazolyl)borates] (M = Co, Ni, Cu ) were prepared using [sodium 4-aminopiperidyldithiocarbamate] and were characterized by IR and UV-visible spectroscopy. A remarkable improvement in the solubility of these metal dithiocarbamates in organic solvents was observed. Furthermore, attempts to covalently graft these complexes onto hexamolybdate cluster were undertaken, and found to be unsuccessful possibly due to the strong oxidizing nature of PPh[subscript]3Br[subscript]2 and hexamolybdate. Although, we were able to successfully tailor the solubility of the dithiocarbamate complexes to suit our needs, our efforts to achieve the primary goal of synthesizing dithiocarbamate based polyoxometalate hybrids have so far been unsuccessful. A series of three pyridyl based ligands i.e., 3,5-di(pyridin-2-yl)-4H-1,2,4-triazol-4-amine, 4-(pyridin-4-ylethynyl)aniline and 4-(pyridin-3-ylethynyl)aniline were synthesized and characterized. Covalent attachment of these ligands to hexamolybdate were attempted following various well-known routes. Although, no evidence of covalent attachment of 3,5-di(pyridin-2-yl)-4H-1,2,4-triazol-4-amine to hexamolybdate was observed, the covalent grafting of 4-(pyridin-4-ylethynyl)aniline and 4-(pyridin-3-ylethynyl)aniline to hexamolybdate cluster was successfully achieved. Characterization of these novel organic-inorganic hybrids was done using IR and NMR spectroscopy as analytical tools. Attempts have been undertaken to obtain single crystals of these hybrids. Also, a novel route involving halogen bonding as a purification and separation technique for pyridyl functionalized hexamolybdate hybrids is also being explored. The novel acetylacetonate moiety has been explored as an imidodelivery reagent for synthesizing hexamolybdate covalent hybrids, wherein [3-(4-((4-aminophenyl)ethynyl)phenyl)-4-hydroxypent-3-en-2-one] ligand has been successfully synthesized and characterized. Traditional methods along with unconventional methods such as heating at elevated temperatures and microwave reaction conditions, have so far proved to be unsuccessful in the synthesis of the hybrids. A series of the corresponding metal complexes have been synthesized and characterized, where the ligand and its corresponding copper(II) complex have been characterized by single crystal XRD. In the crystal structure of the copper complex, the metal ion sits in a slightly distorted square-planar pocket, where no coordination to the -NH[subscript]2 group is observed, which highlights the potential of using it as an imidodelivery reagent.

The development of organic-inorganic hybrid materials is of great interest in thermoelectrics for its potential to combine the desirable characteristics of both classes of materials. Thermoelectric materials must combine low thermal conductivity with high electrical conductivity, but in most materials, thermal and electrical conductivity are closely related and positively correlated. By combining the low thermal conductivity, flexibility, facile processing, and low cost of organic components with the high electrical conductivity and stability of inorganic components, materials with beneficial thermoelectric properties may be realized. Here, we describe the synthesis and characterization of anthracene-containing organic-inorganic hybrid materials for thermoelectric purposes. Specifically, POSS-ANT was synthesized when aminopropylisobutyl-POSS was functionalized with a single anthracene unit via DCC-mediated amide formation. Acrylate-POSS was functionalized with multiple anthracene units in a Heck coupling reaction to synthesize System 1. System 2 was developed through a two-step synthetic process. In the first reaction, (3- acryloxypropyl)methyl dimethyoxy silane was functionalized with anthracene at the 9- position through a Heck coupling reaction. The second reaction was a base-catalyzed solgel process to form polymeric nanoparticles. Finally, System 3 was synthesized through a similar process to System 2, though polymers formed in the initial step. The System 3 precursor was to be developed through a potassium carbonate-catalyzed ether synthesis from 3-(bromopropyl)trimethoxysilane and 9-anthracene methanol, followed by a basecatalyzed sol-gel process to form nanoparticles. The precursor was never isolated because of premature polymerization during the precursor synthesis step, and polymeric nanoparticles were obtained for System 3 during the sol-gel process. These materials were characterized by TEM to reveal the nanostructures that formed upon evaporation from solution. Future work will focus on the characterization of thermoelectric parameters and incorporation into thermoelectric devices.

Inorganic-organic hybrid materials have been developed using sol-gel reactions of a trialkoxysilylated organic compound and a metal or semi-metal alkoxide and applied as coatings on polymeric or metallic substrates. Many of these coatings have demonstrated good to excellent abrasion resistance. Abrasion resistant coatings were prepared by hydrolysis and condensation of mixtures of a triethoxysilylated diethylenetriamine (f-DETA), tetramethoxysilane (TMOS), water and an alcohol in the presence of an acid catalyst (a one-step hydrolysis approach). The influences of many formulation and processing variables on the gelation time, optical properties, hardness and abrasion resistance were investigated. An aminolysis mechanism was also proposed to explain the adhesion between sol-gel derived coatings and polycarbonate substrates promoted by a 3-aminopropyltriethoxysilane (3-APS) primer. FT-IR, GPC, 1H and 13C NMR, XPS experiments were conducted to support this mechanism. The f-DETA/TMOS system is essentially a binary system of an alkyltriethoxysilane (T) and a tetraalkoxysilane (Q). At pH 0-2 and pH 4-5, the relative condensation reactivities of the T and Q species in this system were compared using 29Si NMR spectroscopy. After thermal curing, 13C or 29Si solid state NMR spectroscopy was used to estimate the extent of hydrolysis of the urea linkages in f-DETA, the concentration of residual alkoxysilane groups, and the extent of condensation for both T and Q species. The dependence of the morphology of f-DETA/TMOS gels on the pH and the water concentration was also investigated using AFM, SEM and SAXS. Many other trialkoxysilylated organic compounds containing urea, urethane, epoxy and siloxane linkages were also synthesized and utilized to prepare abrasion resistant coatings via a one-step hydrolysis approach, a two-step hydrolysis approach or a moisture-curing approach. Coatings derived from many of these systems or approaches demonstrated abrasion resistance comparable to that of the f-DETA/TMOS coating. Thin coatings were also derived from cubic octasilicate monomers via hydrosilylation or sol-gel reactions. These coatings were very transparent but unfortunately lacked abrasion resistance.
Ph. D.

Kyoto University (京都大学)
0048
新制・課程博士
博士(工学)
甲第11588号
工博第2534号
新制||工||1344(附属図書館)
23231
UT51-2005-D337
京都大学大学院工学研究科高分子化学専攻
(主査)教授 福田 猛, 教授 伊藤 紳三郎, 教授 金谷 利治
学位規則第4条第1項該当

On the technical platform of hybrid organic-inorganic sol-gel, the integrated optoelectronics in the forms of heterogeneous integration between the hybrid sol-gel waveguide and the high refractive index semiconductors and the nonlinear functional doping of disperse red chromophore into hybrid sol-gel is developed. The structure of hybrid sol-gel waveguide on high index semiconductor substrate is designed with BPM-CAD software. A hybrid sol-gel based on MAPTMS and TEOS suitable for lower cladding for the waveguide is developed. The multi-layer hybrid sol-gel waveguide with good mode confinement and low polarization dependence is fabricated on Si and InP. As proof of concept, a 1 x 12 beam splitter based on multimode interference is fabricated on silicon substrate. The device shows excess loss below 0.65 dB and imbalance below 0.28 dB for both TE and TM polarization. A nonlinear active hybrid sol-gel doped with disperse red 13 has been developed by simple co-solvent method. It permits high loading concentration and has low optical loss at 1550 nm. The second-order nonlinear property of the active sol-gel is induced with corona poling and studied with second harmonic generation. A 3-fold of enhancement in the poling efficiency is achieved by blue light assisted corona poling. The chromophore alignment stability is improved by reducing the free volume of the formed inorganic network from the sol-gel condensation reaction. An active sol-gel channel waveguide has been fabricated using active and passive hybrid sol-gel materials by only photopatterning and spin-coating. An amplitude modulator based on the active sol-gel containing 30 wt.% of DR13 shows an electro-optic coefficient of 14 pm/V at 1550 nm and stable operation within the observation time of 24 days.

The objective of this project was to develop efficient electrode materials for use in an aqueous aluminum-ion battery. This study of electrodes mainly focuses on the development of earth-abundant materials fabricated by a simple hydrothermal process. This project describes the development of highly stable and efficient battery electrodes from different metal oxides from manganese and molybdenum. A cation exchange mechanism is proposed and validated in this thesis where the cations trapped in the electrodes and exchanged during aluminum-ion intercalation and extraction. In short, this thesis focuses on the development of a sustainable aqueous aluminum ion battery.

The thesis work aimed to find appropriate syntheses procedures for the preparation of Nano Building Blocks (NBB) and Nano Particles (NP), starting from organo silanes as molecular precursors, using the Sol-Gel method. NBB were obtained by either non-hydrolytic or in situ water production (ISWP) route, depending on the reactive function’s loading. The obtained NBB were characterised by means of FT-IR, ATR/FT-IR, RAMAN, multinuclear NMR spectroscopies, SEM, N2 physisorption, Thermal analyses (TG/DTA), DSC. NBBs were used to prepare methacrylate-based matrices, which were subsequently exploited in order to produce patternable films by the two photon polymerisation technique (TPP). Epoxy-based matrices were also prepared and the films obtained were patterned by the UV photolithography technique. Both techniques gave high surface resolution patterning. NP were obtained with a modified Stöber method and organosilica NP were obtained. The NP were characterised by FT-IR and NMR spectroscopies. Morphology was observed and sizes calculated using SEM; N2- physisorption and thermal analyses (TG/DTA) were also carried out in order to complete the characterization. DSC measurements were performed on methacryloxypropyl-functionalised NP in order to control the ability to polymerise of the particles. Films of the different organic-modified NP were obtained by spin coating and contact angle measurements were performed. FE-SEM was used in order to observe an eventual change in morphology after thermal treatment under reduced atmosphere. The ability to retain the shape depends on the functional group on the NP. Finally a preliminary study on dye doping was accomplished. The NP were efficiently doped with a fluorescent dye: Rhodamine 6G (R6G). Absorption and emission spectra were recorded with a spectrofluorometer. It is observable that the emission spectra is influenced by the NP’s matrix.

The thesis work aimed to find appropriate syntheses procedures for the preparation of Nano Building Blocks (NBB) and Nano Particles (NP), starting from organo silanes as molecular precursors, using the Sol-Gel method. NBB were obtained by either non-hydrolytic or in situ water production (ISWP) route, depending on the reactive function’s loading. The obtained NBB were characterised by means of FT-IR, ATR/FT-IR, RAMAN, multinuclear NMR spectroscopies, SEM, N2 physisorption, Thermal analyses (TG/DTA), DSC. NBBs were used to prepare methacrylate-based matrices, which were subsequently exploited in order to produce patternable films by the two photon polymerisation technique (TPP). Epoxy-based matrices were also prepared and the films obtained were patterned by the UV photolithography technique. Both techniques gave high surface resolution patterning. NP were obtained with a modified Stöber method and organosilica NP were obtained. The NP were characterised by FT-IR and NMR spectroscopies. Morphology was observed and sizes calculated using SEM; N2- physisorption and thermal analyses (TG/DTA) were also carried out in order to complete the characterization. DSC measurements were performed on methacryloxypropyl-functionalised NP in order to control the ability to polymerise of the particles. Films of the different organic-modified NP were obtained by spin coating and contact angle measurements were performed. FE-SEM was used in order to observe an eventual change in morphology after thermal treatment under reduced atmosphere. The ability to retain the shape depends on the functional group on the NP. Finally a preliminary study on dye doping was accomplished. The NP were efficiently doped with a fluorescent dye: Rhodamine 6G (R6G). Absorption and emission spectra were recorded with a spectrofluorometer. It is observable that the emission spectra is influenced by the NP’s matrix.

ORGANIC AND HYBRID INORGANIC-ORGANIC MATERIALS WITH INTRIGUING EMISSIVE PROPERTIES IN THE SOLID STATE Daniele Malpicci, PhD Thesis, R12760, Università degli Studi di Milano Materials featured by emissive properties in the aggregated form are gaining ever growing attention from the scientific community. In this regard, triimidazo[1,2-a:1',2'-c:1'',2''-e][1,3,5]triazine, TT has recently revealed as an intriguing compound showing, in the solid state, not only intense fluorescence but also room temperature ultralong phosphorescence (RTUP, up to one second) associated with the presence of H aggregates in its crystal structure.[1] The introduction of halogen atoms (Br and I) or chromophoric fragments (2-Fluoropyridine) on the TT scaffold has proven to be a powerful tool to modify both its molecular and solid state photophysical behavior, providing derivatives featured by a complex excitation dependent photoluminescence.[2–5] This PhD thesis work has been devoted to the synthesis and characterization of members of the TT-family by functionalization with different fragments spanning from halogen atoms (Cl[6]) to chromophoric fragments (pyrene,[7,8] pyridine,[9] carbazole). The new derivatives have been photophysically characterized revealing a rich emissive behavior comprising dual fluorescence, molecular phosphorescence and supramolecular room temperature phosphorescence (RTP) in the solid state. Pyrene-substituted TTs have been successfully employed both in the detection of nitroaromatic compounds[10] and in bioimaging.[7] In addition, the properties of TT as a mono-, bi-, and tridentate ligand have been exploited allowing the preparation of one- and three-dimensional (1D, 3D) coordination polymers of Cu(I) and Ag(I) characterized by emission in solid state covering a wide range of UV-Vis spectrum.[11] Finally, TT derivatives functionalized with methylated pyridines or guanidine moieties have been tested as stabilizer for G-Quadruplex structures resulting as promising ligands for such non-canonical DNA folding.[12] [1] E. Lucenti, A. Forni, C. Botta, L. Carlucci, C. Giannini, D. Marinotto, A. Previtali, S. Righetto, E. Cariati, J. Phys. Chem. Lett. 2017, 8, 1894–1898. [2] E. Lucenti, A. Forni, C. Botta, L. Carlucci, C. Giannini, D. Marinotto, A. Pavanello, A. Previtali, S. Righetto, E. Cariati, Angew. Chem. Int. Ed. 2017, 56, 16302–16307. [3] E. Lucenti, A. Forni, C. Botta, L. Carlucci, A. Colombo, C. Giannini, D. Marinotto, A. Previtali, S. Righetto, E. Cariati, ChemPhotoChem 2018, 2, 801–805. [4] A. Previtali, E. Lucenti, A. Forni, L. Mauri, C. Botta, C. Giannini, D. Malpicci, D. Marinotto, S. Righetto, E. Cariati, Molecules 2019, 24, 2552. [5] E. Lucenti, A. Forni, C. Botta, C. Giannini, D. Malpicci, D. Marinotto, A. Previtali, S. Righetto, E. Cariati, Chem. – A Eur. J. 2019, 25, 2452–2456. [6] C. Giannini, A. Forni, D. Malpicci, E. Lucenti, D. Marinotto, A. Previtali, L. Carlucci, E. Cariati, Eur. J. Org. Chem. 2021, 2021, 2041–2049. [7] A. Previtali, W. He, A. Forni, D. Malpicci, E. Lucenti, D. Marinotto, L. Carlucci, P. Mercandelli, M. A. Ortenzi, G. Terraneo, C. Botta, R. T. K. Kwok, J. W. Y. Lam, B. Z. Tang, E. Cariati, Chem. - A Eur. J. 2021, 27, 16690–16700. [8] D. Malpicci, C. Giannini, E. Lucenti, A. Forni, D. Marinotto, E. Cariati, Photochem 2021, 1, 477–487. [9] E. Lucenti, A. Forni, A. Previtali, D. Marinotto, D. Malpicci, S. Righetto, C. Giannini, T. Virgili, P. Kabacinski, L. Ganzer, U. Giovanella, C. Botta, E. Cariati, Chem. Sci. 2020, 11, 7599–7608. [10] M. Formenti, D. Blasi, E. Cariati, L. Carlucci, A. Forni, C. Giannini, M. Guidotti, S. Econdi, D. Malpicci, D. Marinotto, E. Lucenti, Dye. Pigment. 2022, 206, 110637. [11] D. Malpicci, E. Lucenti, A. Forni, D. Marinotto, A. Previtali, L. Carlucci, P. Mercandelli, C. Botta, S. Righetto, E. Cariati, Inorg. Chem. Front. 2021, 8, 1312–1323. [12] D. Malpicci, S. Andolina, S. Di Ciolo, E. Lucenti, E. Cariati, S. Marzano, B. Pagano, J. Amato, A. Randazzo, C. Giannini, European J. Org. Chem. 2022, 2022, DOI 10.1002/ejoc.202200718.

Layered double hydroxides (LDH) containing NiAl or NiV of varying M(II):M(RI) (2:1, 5:1, 9:1 for NiAl and 2:1, 5:1 for NiV) ratios have been prepared by coprecipitation and characterized by XRD, elemental analysis, and FT-IR. The LDHs electrochemical properties were investigated in half-cells to determine their potential application as positive electrode in Ni-Cd and NiMH batteries. The Ni2Al LDH exchanges the most electrons (up to 1.6) and is the most stable during discharging in the KOH electrolyte. The large quantity of electrons and accrued stability was attributed to the aluminium in the layers acting in a two fold manner: High charge to radius ratio increased the electrostatic interaction between the anions and the metal layers increasing the stability of the LDHs and the increase in Bronsted acidity of the hydroxyl groups was accredited for the high exchange of electrons. Notwithstanding the high exchange of electrons of the NiAl LDHs the powders exhibit lower discharge capacity compared to commercial electrode material (beta-Ni(OH) 2) due to their low density. The NiV LDHs only exchanged up to 1.2 electrons (Ni2V) and were found only stable up to a maximum of 14 days in electrolytic solutions of the cells. In the second part of the study ZnAl LDHs were synthesized and intercalated with phenyl phosphonic acid (PPA) or 1,4-phenylene bis phosphonic acid (B-PPA) in order to create microporous materials. The compounds were characterized by XRD, chemical, IR and solid state NMR analysis in addition to being tested for microporosity. The ZnAl LDHs treated with phenyl phosphonic acid gave rise to materials with a d spacing of 14.7A and when treated to B-PPA resulted in materials with a d spacing of 9.6 A. The results showed that the grafting of both phosphonates to the metal layers had occurred. The d spacing of 14.7 A was interpreted as being due to a bilayer of PPA molecules in head to head configuration in the layers. The d spacing of 9.6 A was consistent with a monolayer of B-PPA molecules cross-linking the metal layers of the material. Both materials exhibited little or no microporosity due to the "packing" of the phosphonate moieties in the layers. The last section of the thesis consisted of attempting to synthesize MCM or FSM type molecular sieves by the treatment of ZnAl LDH with hexadecane sulfonic acid or sodium dodecyl sulfate used as templates under different reaction conditions. The materials were characterized by XRD, chemical analysis and IR analysis. The results were consistent with LDHs intercalated with either a monolayer or a bilayer arrangement of surfactant molecules and therefore did not exhibit MCM or FSM mesoporous frameworks.