Switchable metal–organic frameworks (MOFs) change their structure in time and selectively open their pores adsorbing guest molecules, leading to highly selective separation, pressure amplification, sensing, and actuation applications. The 3D engineering of MOFs has reached a high level of maturity, but spatiotemporal evolution opens a new perspective toward engineering materials in the 4th dimension (time) by t-axis design, in essence exploiting the deliberate tuning of activation barriers. This work demonstrates the first example in which an explicit temporal engineering of a switchable MOF (DUT-8, [M1M2(2,6-ndc)2dabco]n, 2,6-ndc = 2,6-naphthalene dicarboxylate, dabco = 1,4diazabicyclo[2.2.2]octane, M1 = Ni, M2 = Co) is presented. The temporal response is deliberately tuned by variations in cobalt content. A spectrum of advanced analytical methods is presented for analyzing the switching kinetics stimulated by vapor adsorption using in situ time-resolved techniques ranging from ensemble adsorption and advanced synchrotron X-ray diffraction experiments to individual crystal analysis. A novel analysis technique based on microscopic observation of individual crystals in a microfluidic channel reveals the lowest limit for adsorption switching reported so far. Differences in the spatiotemporal response of crystal ensembles originate from an induction time that varies statistically and widens characteristically with increasing cobalt content reflecting increasing activation barriers.

Photoschalter sind Moleküle, die eine reversible lichtgesteuerte Umwandlung zwischen zwei Zuständen mit unterschiedlichen Eigenschaften durchlaufen. In den letzten zehn Jahren hat der Einbau dieser photochromen Moleküle in intelligente, auf Stimuli ansprechende Materialien zunehmende Aufmerksamkeit erregt, da sie die einzigartige Fähigkeit bieten, makroskopische Eigenschaften mit einem externen optischen Stimulus reversibel zu verstärken und zu verändern. Die begrenzte Leistung von Photoschaltern in festen Medien bleibt eine Herausforderung. In diesem Zusammenhang werden in dieser Arbeit zwei wichtige Aspekte näher untersucht. Erstens der Prozess der Entwicklung neuer Photoschalter mit maßgeschneiderten Eigenschaften und zweitens die Implementierung von Photoschaltern in feste Materialien und die damit verbundenen Herausforderungen. Im ersten Teil dieser Arbeit wurde Dynamisch-kovalente Chemie (DCC) verwendet, um die Entdeckung und Entwicklung einer neuartigen Klasse von Photoschaltern mit drei Zuständen zu beschleunigen. Die dynamische Natur der zentralen Doppelbindung von α-Cyanodiarylethenen wurde genutzt, um ein thermodynamisches Gleichgewicht mit anderen Arylacetonitrilen herzustellen. Die entwickelte Methode kombiniert eine schnelle Diversifizierung mit einer Rasterung auf spezifische Eigenschaften, die durch einen externen Stimulus aufgedeckt werden, und ermöglicht die effiziente Untersuchung der Beziehung zwischen Struktur und den zugehörigen Eigenschaften. Im zweiten Teil der Arbeit wird die Entwicklung und die Synthese eines Zweikomponenten-Kern-Schale-MOFs mit einem internen nicht-funktionalisierten Kompartiment, das von einer dünnen photoschaltbaren Außenschale bedeckt ist, vorgestellt. Diese Strategie ermöglicht ein effizientes Schalten des Chromophors und die resultierende dünne „intelligente“ Schale fungiert als modulare kinetische Barriere für die molekulare Gastdiffusion in das Material, die durch Licht gesteuert werden kann. / Photoswitches are molecules that undergo a reversible light-triggered conversion between two states with different properties. In the past decade, the incorporation of these photochromic molecules in smart stimuli-responsive materials has gained increased attention as it offers the unique ability to reversibly amplify and change macroscopic properties with an external optical stimulus. The limited performance of photoswitches in solid mediums remains a challenge. In this context two important aspects are studied in more detail in this thesis. First, the process of developing new photoswitches with tailored properties and second, the implementation of photoswitches in solid materials and the challenges associated with it. In the first part of this thesis dynamic covalent chemistry (DCC) was used to accelerate the discovery and development of a novel three-state photoswitch class. The dynamic nature of the central double bond of α-cyanodiarylethenes was exploited to establish a thermodynamic equilibrium with other arylacetonitriles. The developed DCC tool combines fast and efficient diversification with screening for specific photochemical properties revealed by an external stimulus, enabling the rapid study of the relationship between structure and the associated properties. The second part of this thesis summarizes the design and synthesis of a two-component core-shell MOF with an internal non-functionalized compartment covered by a thin photoswitchable outer shell. This strategy allows efficient switching of the chromophore and the resulting thin “smart” shell acts as a modular kinetic barrier for molecular guest diffusion into the material that can be controlled by light.

L’objectif de ce travail étaient le développement de catalyseurs hétérogènes efficaces pour promouvoir des réactions asymétriques, en utilisant la polymérisation oxydante ou la formation de polymères de coordination. De nouveaux complexes de salen Co(III) chiraux modifiés par des groupements aromatiques sur les position 5, 5’ ont été préparés et testés dans le dédoublement cinétique hydrolytique (HKR) des époxydes terminaux en conditions homogènes. Ces complexes ont été ensuite engagés dans les polymérisations oxydantes électrochimiques ou chimiques, et une stratégie de copolymérisation a fourni des polymères chiraux très efficaces et stables pour catalyser l’HKR dans des conditions hétérogènes. Nous avons alors cherché à préparer un catalyseur capable de catalyser deux réactions en cascade, en copolymérisant deux complexes de salen portant des métaux différents. Pendant ces études, les complexes de salen Mn ont révélé leur participation active à la réaction d’HKR des époxydes terminaux catalysée par les complexes de salen Co(III), en augmentant l’excès énantiomérique du produit de façon significative. Les études mécanistiques ont été ensuite réalisées pour tenter de comprendre le rôle des complexes de Mn dans cette réaction. De plus, des complexes de salen fonctionnalisés par le groupement pyridine ou le groupement de type acide isophtalique ont été synthétisés. Ces complexes ont été utilisés pour préparer de nouveaux réseaux de polymères de coordination poreux chiraux (collaboration avec l’équipe LCI de l’ICMMO et l’Institut Lavoisier à Versailles), qui sont ensuite testés comme catalyseurs hétérogènes dans la réaction de Henry asymétrique et la réaction d’HKR. / The aim of this work was to prepare new chiral heterogeneous catalysts for asymmetric catalysis by oxidative polymerization of chiral organometallic complexes or by formation of chiral metal organic frameworks. New chiral salen Co(III) complexes modified by oxidizable aromatic groups at position 5,5’ have been prepared and tested as homogeneous catalysts in the Hydrolytic Kinetic Resolution (HKR) of terminal epoxides. These complexes have also been engaged into the oxidative electrochemical and chemical polymerization, and a copolymerization strategy has afforded very efficient and stable heterogeneous catalysts for the HKR. The idea of copolymerization has then been extended to the copolymerization of two salen complexes with different metals, which is expected to promote successively two different asymmetric transformations. During preliminary investigations, the salen Mn complexes have been found to be able to enhance the catalytic performance of salen Co(III) complexes in the HKR by increasing significantly the enantiomeric excess of the products. Mechanistic studies have thus been realized to understand the role of salen Mn complexes in this reaction. Besides, some chiral salen complexes functionalized by pyridine or isophtalic acid groups have been synthesized for the preparation of new chiral metal organic frameworks (collaboration with LCI of ICMMO and Institut Lavoisier of Versailles), which have also been tested in the asymmetric Henry reaction and the HKR as heterogeneous catalysts.

Crystal growth and characterization of few multifunctional materials with perovskite (ABX3) structure are discussed in this thesis. Efforts were made to modify the magnetic and electric behaviour of these materials by selective tuning of A, B and X components. Structural, magnetic and dielectric characterization are detailed in various chapters for doped (A and B site) rare-earth manganites and organometallic compounds with different (Chloride or formate) anions. The relevant aspects of crystal structure and its relationship with ordered ground states are discussed in the introductory chapter. A detailed review of prominent theories pertaining to magnetic and ferroelectric ordering in the literature is provided. Growth of various inorganic compounds by solid-state reaction and floating zone method as well as use of solvothermal techniques for growing organometallic compounds are discussed. Material preparation, optimization of crystal growth processes and results of characterization are addressed in various chapters. The effect of Yttrium doping on structural, magnetic and dielectric properties of rare-earth manganites (RMnO3 where R = Nd, Pr) has been investigated. Neutron diffraction studies (Pr compounds) confirm A-type antiferromagnetic structure and fall in transition temperature as the Yttrium doping level increases. Diffraction experiments in conjunction with dc magnetization and ac susceptibility studies reveal magnetic frustration in excess Yttrium dopedcompounds. When mutliglass properties of 50% B-site doped Nd2NiMnO6 were investigated, evidence of re-entrant cluster glass phase was seen probably due to presence of anti-site disorder. The relaxor-like dielectric behaviour arises from crossover of relaxation time in grain and grain boundary regions. Multiferroic behaviour of the organometallic compound (C2H5NH3)2CuCl4 as well as the ferroelectric transition were investigated in detail. The role of Hydrogen bond ordering in driving structural transitions is elucidated by low temperature dielectric and Raman studies in (C2H5NH3)2CdCl4. It was found possible to tune the magnetic and ferroelectric properties in metal formate compounds (general formula AB(HCOO)3) by selectively choosing organic cations [(CH3)2NH2+; C(NH3)3+] and transition metal ion [B = Mn, Co and Cu]. The nature of magnetic ordering and transition temperature could be altered by the transition metal ion. The effect of reorientation of organic cations which leads to ferroelectric nature is discussed using dielectric and pyroelectric data. Significant results are summarized in the chapter outlining general conclusions. Future prospects of work based on these observations are also provided. The conclusions are corroborated by detailed analysis of experimental data.

In the last few years, considerable efforts have been given to develop sensitive and effective sensors for explosive materials and to generate systems which exhibit high luminescence in both solution and solid-state. The increasing number of terrorist activities around the world have prompted scientists to design effective ways to detect and disarm even the trace amount of explosives. The nitroaromatics (NACs) are the common constituents of most of the explosives due to high explosive velocity and ease of availability. The NACs were extensively used as the main constituents in landmines until World War II. Apart from their explosive behavior, the NACs are well-known environmental pollutants. The industrial waste and the leakages from unexploded landmines are the major contributors towards the soil and ground water contamination. Presently for effective detection of trace amount of explosives, skilled canines and metal based detectors are commonly used. The canines are trained for a specific type of explosives which limit their ability to detect different types of substrates. The chemical sensors that work on the principle of colorimetric and/or fluorimetric detection techniques have emerged as suitable alternative due to cheap production cost, portability and sensitivity. Different types of materials including conjugated polymers, metal-organic frameworks (MOFs), and quantum-dots have been reported as efficient chemosensors for NACs. However, poor solubility in the common organic solvents, low solid-state fluorescence, very high molecular weight and lack of signal amplification have restricted the application of these material for in-field testing. Renewed interests have been invested in small molecule based systems; and metal-organic discrete molecular architectures due to precise control over their photophysical properties and the supramolecular interaction among neighboring molecules that facilitates energy migration among the molecular backbone. On the other hand, recently post-synthetic modification of different molecular systems including MOFs and polymers has emerged as a potential technique to incorporate desired functional groups into the system and to tune their properties with the retention of basic structures. Reports on the post-synthetic modification of discrete metal-organic architectures are rare due to the delicate nature of the metal-organic bonds that ruptures on mild environmental changes. Therefore, post-synthetic functionalization of discrete molecular systems using mild reaction conditions will open up a myriad of possibilities to generate new systems with desired characteristics. Chapter 1 of the thesis will briefly discuss the history of different explosive materials including different detection methodologies that are widely used. It will also include a brief discussion on different small molecular systems with high solid-state luminescence. In Chapter 2, design and synthesis of triphenylamine-based two Platinum(Pt)(II) molecules functionalized with carboxylic acid and ester groups including their organic analogues have been discussed. The triphenylamine core was chosen due its unique non-planarity and luminescence. On the other hand, Pt(II) center was incorporated to increase intermolecular spacing in solid-state that can induce high luminescence. Scheme 1. Schematic representation of fluorescence quenching using small molecules. All the four molecules were found to be highly sensitive towards NACs including picric acid and dinitrophenol. Although the molecules exhibited similar sensitivity in solution, the carboxylic acid analogues demonstrated superior sensitivity in solid-state. Careful observation of the crystal structures of the systems revealed the acid analogues were oriented in a 2-D grid-like pattern that facilitated energy migration among neighboring molecules (Scheme 1.). Chapter 3 describes design, synthesis, and NACs sensing behavior of anthracene-based four purely organic small molecules. The molecules exhibited high selectivity towards picric acid only. All the molecules were found to be highly emissive in both solution and solid-state due to the vinylanthracene backbone (Scheme 2.). Scheme 2. Schematic representation of fluorescence quenching and solid-state sensing behavior. Chapter 4 discusses the strategy to develop mechano-fluorochromic and AIE active triphenylamine-based Pt(II) complex and its organic analogue. The twisted triphenylamine backbone restricted molecular close packing in solid-state; and weak C-H-- interactions were utilized to hinder the motion of the phenyl rings. As a result, the molecules were highly emissive in solid-state. Grinding disrupted the intermolecular interactions and thus mechano-fluorochromic behavior was observed. Due to twisted backbone, the molecules were also found to be AIE active. Both the systems containing terminal aldehyde groups were finally utilized for selective detection of biomolecule cysteine (Scheme 3.). Scheme 3. Mechano-fluorochromic and AIE behavior of the triphenylamine based Pt(II) complex. In Chapter 5 vinylanthracene-based linear donor was used in combination with carbazole-based 90° and triphenylamine-based 120° Pt(II) acceptors to generate (4+4) and (6+6) molecular squares and hexagons, respectively. The vinylanthracene backbone imparts high solution and solid-state luminescence to the system as well as made them AIE active. The molecules were further investigated for the solution and solid-state sensing for NACs and found to be effective for trinitrotoluene (TNT) and dinitrotoluene (DNT) (Scheme 4.). Scheme 4. Schematic representation of AIE active molecular square and its NACs sensing. Chapter 6 describes the formation of Pd3 self-assembled molecular trinuclear barrels containing triphenylamine imidazole donors and Pd(II) acceptors. Using Knoevenagel condensation the aldehyde group present in the barrel was post-synthetically functionalized with Meldrum’s acid. From spectroscopic characterization, it was proved that the structural integrity remained intact after the post-modification treatment (Scheme 6.). Surprisingly, pre-synthetic modification of the donor alone with Meldrum’s acid followed by self-assembly treatment with the Pd(II) ion did not yield trigonal barrel 6.8. Scheme 6. Post-synthetic functionalization of trinuclear barrels using Knoevenagel condensation.(For colour pictures pl see the abstract pdf file)

The present thesis provides a systematic investigation of coordination polymers of 3d, rare-earth (4f) and main group element (Bi) using both rigid aromatic, flexible aliphatic linkers. Luminescent sensing behavior towards nitro aromatics, metal ions and ferroelectric behavior have been investigated using some of the prepared compounds. The possible usefulness of lone pair on the structure has been investigated using bismuth based coordination polymers. The thermal and optical behavior of lanthanide coordination polymers (Ce, Pr and Nd) have also been studied. Chapter 1 An Overview of Coordination Polymer (CP) Compounds This chapter presents a brief introduction to coordination polymer (CP) compounds. Starting from the brief historical background on coordination compounds, this chapter shed light on some earlier developments in this family of compounds by Yaghi, Robson and others. The usefulness of carboxylate and imidazolates in construction of some important coordination polymer compounds like MOF-5, HKUST-1, ZIFs, MIL-53, UiO-66, CD-MOF-1 etc has been described in detail along with its properties. The coordination polymers exhibit many important properties and some of the properties like sorption, separation, ionic conductivity, catalysis and ferroelectricity have been discussed briefly and summerized. Chapter 1 also provides the general synthetic and characterization approaches that have been employed during the present studies. Chapter 2 Part A: Adenine Based Coordination Polymers with Cyclohexane dicarboxylic acids This chapter presents the synthesis, structure and properties of four new coordination polymers [Zn4(C8H10O4)2.5(C5H4N5)3.2H2O].7H2O.2DMA (I), [Cd3(C8H10O4)2(C5H4N5)2.H2O] (II), [Cd(C8H11O4)2(C5H5N5)2.2H2O] (III), [Cd(C8H10O4)(C7H8N5O).H2O]. 4H2O (IV), (CHDA = cyclohexane dicarboxylic acid, ad = adenine, DMA = dimethylacetamide, 9-HEA = 9-hydroxyethyl adenine). The compound I and II forms three-dimensional structure having distinct arrangements of 1,4-CHDA and adenine units with Zn and Cd metals respectively. The molecular complex unit is observed in compound III with 1,2-CHDA and adenine. Compound IV forms two-dimensional structure with 9-HEA and 1,2-CHDA. The observation of base-pairing interactions in the above compounds is noteworthy. In compounds I, II and IV amino groups are appears to be free and utilized for the detection of nitro aromatic explosives through fluorescence quenching. The results revealed that the emission behavior of the present compounds is greatly influenced by the hydroxyl nitroaromatic analyses like indophenol, dinitrophenyl and trinitrophenols with very low detection limits. The compound I also exhibits considerable sensitivity towards metal ion detection, especially Fe2+/Fe3+, Cr3+, Ag+ and Hg2+ ions in solution. The presence of free nitrogen sites in compound II has been explored for the base catalyzed Knoevenagel condensation reaction, the quantitative yields are observed with various aldehyde substrates. Part B: Adenine Based Coordination Polymer with Oxydiacetic acid: [Cd2(C4H4O5)2(C5H5N5)].H2O.DMA The synthesis, structure and properties of a Cd based coordination polymer with oxydiacetic acid and adenine, [Cd2(C4H4O5)2(C5H5N5)].H2O. DMA is described. The compound has a two-dimensional structure formed by the connectivity involving Cd and oxydiacetic acid. The adenine ligand binds with the Cd metal center through the pyrimidine nitrogen and hangs in the inter layer spaces. The layers are stacked in a ABAB.... fashion and the inter layer spaces occupied by the dimethyl amine and water molecules. The water molecules are very labile and its removal can be accomplished by heating the sample at 100°C, which is also confirmed by the single crystal XRD, PXRD and IR studies. The availability of free amino groups of adenine molecule has been utilized for the detection of nitroaromatics, especially nitrophenols with good sensitivity. The amino group was also found to be useful in catalyzing Knoevenagel condensation reactions. Chapter 3: Rare-Earth Metal Carboxylates: Ln2(µ3-OH)(C4H4O5)2(C4H2O4)].2H2O [Ln=Ce, Pr and Nd] This chapter describes synthesis, structure and properties of series of rare-earth based compounds, [Ln2(µ3-OH)(C4H4O5)2(C4H2O4)].2H2O (Ln = Ce, Pr and Nd). The malic acid and fumaric acid form part of the structure. The lanthanide centers are connected by the malate units to form a two dimensional layers, which are pillared by fumarate units forming the three-dimensional structure. Overall, structure can be described as I2O1 type inorganic in two-dimension (Ln-O-Ln layers) and organic in one dimension. The extra framework water molecules form a dimer and occupy the channels. The robustness of the framework was reflected in terms of facile removal and reinsertion of the water molecules, which is also confirmed by single crystal XRD, variable temperature IR and cyclic TGA study. The presence of water dimers and weakly interacting water chain suggested the possibility of proton migration in these compounds. Proton conductivity studies reveal the conductivity values of ~2.85 x 10-6 Ω-1cm-1 at 98% relative humidity. The optical studies revealed an up-conversion behavior involving more than one photon for the neodymium compound. Chapter 4: Bismuth Carboxylates with Brucite and Fluorite Related Structures The synthesis, structure and properties of three new bismuth based coordination polymers have been described in this chapter. The compounds [C4N2H10][Bi(C7H4NO4)(C7H3NO4)].H2O (I), [Bi(C5H3N2O4) (C5H2N2O4)] (II) and [Bi(µ2-OH)(C7H3NO4)] (III) were isolated employing hydrothermal condition with three different heterocyclicdicarboxylic acids, 3,6-pyridinedicarboxylic acid, 4,5-imidazoledicarboxylic acid and 3,4-pyridinedicarboxylic acid respectively. The structures of all the compounds have linkages between Bi2O2 and the corresponding dicarboxylate forming a simple molecular unit in I, a bilayer arrangement in II and a three-dimensional extended structure in III. The topological arrangement of the nodal building units in the structures resembles brucite related layers in II and fluorite related arrangement in compound III. By utilizing the secondary interactions, the structure of III can be correlated to a Kagome related net. The observation of such classical inorganic related structures in the bismuth carboxylates is noteworthy. Heterogeneous catalytic studies indicate Lewis acidic nature in the bismuth center in all three compounds. Chapter 5: Solvent dependent Delamination, Restacking and Ferroelectric studies in a Two-Dimensional Compound [NH4][Ag3(C9H5NO4S)2(C13H14N2)2].8H2O This chapter describes synthesis, structure, water dependent delamination/restacking and ferroelectric behavior in a layered coordination polymer compound, [NH4][Ag3(C9H5NO4S)2(C13H14N2)2].8H2O. The compound has a two-dimensional structure with the water molecules occupying the inter-lamellar spaces. The lattice water molecules can be fully removed and reinserted, which accompany the crystalline-amorphous-crystalline transformation. This transformation resembles the collapse/delamination and re-stacking of the layers. This transformation has also been investigated by in-situ IR and PXRD studies. The presence of a natural dipole (anionic framework and cationic ammonium ions) along with the non-centrosymmetric space group gives rise to a room-temperature ferroelectric behavior to the compound with saturation polarization (Ps) of 1.95 μC/cm2 and remnant polarization of 0.63 μC/cm2. The temperature dependent dielectric measurements indicate that the ferroelectric-paraelectric transformation occurs at 320 K. The ferroelectric-paraelectric transformation also follows the crystalline-amorphous-crystalline transitions.

MOF-5 ist der Archetyp einer neuartigen Klasse hochporöser Materialien, den Metal Organic Frameworks, die unter anderem zur Anwendung als effektive Gasspeicher geeignet sind. Im Rahmen dieser Arbeit werden die seiner Bildung zugrunde liegenden Reaktionen untersucht. Aus den Erkenntnissen dieser Untersuchungen wurden zwei neue Syntheseverfahren entwickelt. Eines der Verfahren beruht auf der Phasenumwandlung von Zinkterephthalaten und ermöglichte die Laborsynthese von MOF-5 in 100 g-Mengen. Ein zweites Verfahren bedient sich des Strukturaufbaus mit Hilfe vorgefertigter anorganischer Cluster, wodurch erstmals die Synthese von MOF-5-Homologen anderer Metalle als Zink gelang.

Two-dimensional conjugated metal–organic frameworks (2D c-MOFs), possessing extended π–d conjugated planar structure, are emerging as a unique class of electronic materials due to their intrinsic electrical conductivities. Taking advantage of the large-area flat surface, 2D c-MOF thin films allow facile device integration with sufficient electrode contact, high device stability, and high charge transport, thereby emerging as appealing active layers for a broad range of electronic applications. Synthesis and device investigation of thin films are of great importance for their further development, which are systematically summarized in the current review. Here, the authors firstly introduce the molecular structures of representative 2D c-MOFs and present the fundamental understanding on structure–property relationships. After that, the state-of-art synthetic methodologies toward high-quality 2D c-MOF thin films are summarized, including exfoliation and reassembly (ERA), liquid-interface-assisted synthesis (LIAS), and chemical vapor deposition (CVD). By considering the advantages of 2D c-MOF films in device integration, remarkable progress in (opto-)electronic device applications are discussed, such as field-effect transistors (FETs), chemiresistive sensors, photodetectors, superconductors, and thermoelectrics. In the end, the remained challenges about the development of 2D c-MOF films for (opto-)electronics are highlighted and possible future directions are proposed to address these challenges.

[ES] La presente Tesis Doctoral ha investigado el desarrollo de fotocatalizadores heterogéneos tipo MOF con topología UiO-66 y MIL-125 para la obtención de combustibles solares a partir del agua y del CO2. Inicialmente, en la introducción se ha revisado el estado del arte actual sobre el empleo de combustibles fósiles, las energías renovables y los combustibles solares como vectores energéticos. En esta sección se ha enfatizado sobre los procesos de fotocatálisis basados en semiconductores inorgánicos y MOFs para obtener combustibles solares. Los resultados de la tesis indican que el material tipo MOF UiO-66(Zr)-NH2 es un fotocatalizador más eficiente que sus análogos UiO- 66(Zr)-X (X: H o NO2) o que el MOF de referencia de titanio MIL-125(Ti)-NH2 para la obtención de hidrógeno a partir de la mezcla de agua y glicerol. Por otro lado, se ha demostrado la posibilidad de desarrollar materiales UiO- 66(Zr)-X (X: NH2 o NO2) con defectos estructurales introducidos con ácido acético o trifluoroacético como moduladores y que presentan actividades fotocatalíticias y eficiencias de separación de carga fotoinducida mejoradas para la generación de hidrógeno a partir de mezclas de agua y/o metanol. En esta Tesis también se ha demostrado la importancia del ligando 2- nitrotereftalato en la preparación de fotocatalizadores activos mono- o bimetálicos de Zr(IV) y Zr(IV)/Ti(IV) con topología UiO-66 respecto a los análogos preparados con el ligando 2-aminoteftalato. El material RuOx@UiO- 66(Zr/Ti)-NO2 mostró la máxima actividad fotocatalítica para la reacción de hidrogenación en fase gas de CO2 a CH4 y se propuso que opera bajo un mecanismo dual fotoquímico y fototérmico. / [CA] La present Tesi Doctoral ha investigat el desenvolupament de fotocatalitzadors heterogenis tipus MOF amb topologia UiO-66 i MIL-125 per a l'obtenció de combustibles solars a partir de l'aigua i del CO¿. Inicialment, en la introducció s'ha revisat l'estat de l'art actual sobre l'ús de combustibles fòssils, les energies renovables i els combustibles solars com a vectors energètics. En esta secció s'ha emfatitzat sobre els processos de fotocatàlisis basats en semiconductors inorgànics i MOFs per a obtindre combustibles solars. Els resultats de la Tesi indiquen que el material UiO- 66(Zr)- NH2 és un fotocatalizador més eficient que els anàlegs UiO- 66(Zr)- X (X: H o NO2) o que el referent de MOF de titani MIL-125(Ti)-NH2 per a l'obtenció d'hidrogen a partir de mescles d'aigua i glicerol. D'altra banda, s'ha demostrat la possibilitat de desenvolupar materials UiO-66(Zr)-X (X: NH2 o NO2) amb defectes estructurals introduïts amb àcid acètic o trifluoroacétic com a moduladors i que presenten activitats fotocatalítics i eficiències de separació de càrrega fotoinducida millorades per a la generació d'hidrogen a partir de mescles d'aigua i/o metanol. En esta tesi també s'ha demostrat la importància del lligant 2- nitrotereftalat en la preparació de fotocatalitzadors actius mono- o bimetàl·lics de Zr(IV) i Zr(IV)/Ti(IV) amb topologia UiO-66 respecte als anàlegs preparats amb el lligant 2-aminoteftalat. El material RuOx@UiO- 66(Zr/Ti)-NO2 va mostrar la màxima activitat fotocatalítica per a la reacció d'hidrogenació en fase gas de CO¿ a CH4 i es va proposar que opera per un mecanisme dual fotoquímic i fototérmic. / [EN] This PhD Thesis has investigated the development of heterogeneous MOF- type photocatalysts with UiO-66 and MIL-125 topology to obtain solar fuels from water and CO2. Initially, the introduction has reviewed the current state of the art on the use of fossil fuels, renewable energies and solar fuels as energy carriers. In this section, emphasis has been placed on photocatalysis processes based on inorganic semiconductors and MOFs to obtain solar fuels. The results of the thesis indicate that the MOF-type material UiO-66(Zr)-NH2 is a more efficient photocatalyst than the analogues UiO-66(Zr)-X (X: H or NO2) or the titanium MOF MIL-125(Ti)-NH2 for obtaining H2 from the mixtures of water and glycerol. On the other hand, the possibility of developing UiO-66(Zr)-X (X: NH2 or NO2) materials with structural defects introduced with AA or TFA as modulators and presenting enhanced photocatalytic activities and photoinduced charge separation efficiencies for the generation of H2 from water and/or CH3OH mixtures has been demonstrated. This Thesis has also demonstrated the importance of the 2-nitroterephthalate ligand in the preparation of mono- or bimetallic Zr(IV) and Zr(IV)/Ti(IV) active photocatalysts with UiO-66 topology with respect to the analogues prepared with the 2-aminoterephthalate ligand. The RuOx@UiO-66(Zr/Ti)-NO2 material showed the highest activity compared to RuOx@UiO-66(Zr/Ti)-NO2 material. / Rueda Navarro, CM. (2024). Metal-Organic Framework-Based Photocatalysts for Fuels Production [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/213302