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This dataset includes the positron data.

Metal-organic frameworks (MOFs) stand as pivotal porous materials with exceptional surface areas, adaptability, and versatility. Positron Annihilation Lifetime Spectroscopy (PALS) is an indispensable tool for characterizing MOF porosity, especially micro- and mesopores in both open and closed states. Notably, PALS offers porosity insights independently of probe molecules, vital for detailed characterization without structural transformations. This study explores how metal ion states in MOFs affect PALS results. We find significant differences in measured porosity due to paramagnetic or oxidized metal ions compared to simulated values. By analyzing CPO-27(M) (M=Mg, Co, Ni), with identical pore dimensions, we observe distinct PALS data alterations based on metal ions. Paramagnetic Co and Ni ions hinder and quench positroni-um (Ps) formation, resulting in smaller measured pore volumes and sizes. Mg only quenches Ps, leading to underestimated pore sizes without volume distortion. This underscores metal ions' pivotal role in PALS outcomes, urging caution in interpreting MOF porosity.

Nanosensors based on surface-enhanced Raman spectroscopy (SERS) have emerged as a class of promising optical tools for the ultrasensitive quantification of metal ions of environmental and biological interest. A central bottleneck in this field is the availability of suitable surface receptors able to convert the selective binding with these vibrationless analytes into measurable SERS signals. In this work, we tackle this issue by employing a hybrid substrate comprising a highly SERS-active plasmonic core and a ZIF-8 metal-organic framework (MOF) shell. The ZIF-8 shell firmly captures aromatic receptors close to the plasmonic structure regardless of their intrinsic affinity for the metallic surface and without altering their ability to coordinate metal ions. Furthermore, it imparts molecular sieving abilities enabling the direct use of the SERS sensing platform in complex media such as biological fluids. This was demonstrated by using different classes of chromogenic reagents (bathocuproine, a 2,6':2′,2″-terpyridine derivative, and Arsenazo III) which were exploited for the SERS detection of both transition and alkaline earth metal ions (i.e., divalent copper, cobalt and calcium ions). Notably, we successfully applied this approach for the detection of Cu(II) in untreated urine samples for Wilson's disease diagnosis. Overall, we believe this class of multifunctional hybrid substrates will serve as a valuable material for expanding the applicability of SERS spectroscopy in real-life environmental and biomedical metal ions analysis.

Understanding the impact of shaping processes on solid adsorbents is critical for the implementation of MOFs in industrial separation processes or as catalytic materials. Production of MOF-containing shaped particles is typically associated with loss of porosity and modification of acid sites, two phenomena that affect their performance. Herein, we report a detailed study on how extrusion affects the crystallinity, porosity, and acidity of the aluminium fumarate MOF with clays or SiO2 gel binders. Thorough characterization showed that the clay binders confer the extrudates a good mechanical robustness at the expense of porosity, while silica gel shows an opposite trend. The CO2 selectivity towards CH4, of interest for natural gas separation processes, is maintained upon the extrusion process. Moreover, probe FTIR spectroscopy revealed no major changes in the types of acid sites. This study highlights that these abundant and inexpensive clay materials may be used for scaling MOFs as active adsorbents.

Cancer is the uncontrolled growth of cells in the body and is considered as one of the major causes of death globally. There are several cytotoxic chemotherapeutic agents used to treat cancer including methotrexate, 5-fluorouracil, cisplatin, tamoxifen, doxorubicin and others. Although billions of dollars have been spent on cancer research to develop these chemotherapies, it still remains a major illness for mankind partly due to the shortcomings of these therapies. These shortcomings include low targeting specificity, severe side effects (due to high doses) and poor pharmacokinetics. To avoid these drawbacks, anti-cancer drug delivery systems have been developed recently using nanocarriers including liposomes, micelles, polyelectrolyte capsules and others. One of the recent class of nanoparticles investigated for chemotherapeutic use are metal organic frameworks (MOFs) which are hybrid polymers that consist of metal ions or clusters and organic ligands. MOFs are used in many applications including gas/vapor separation, gas storage, catalysis, luminescent materials, and biomedical imaging. These structures have additional features that promote their use as drug carriers in the biomedical field. First, they are nontoxic, biodegradable and have the ability to carry high loadings of the anti-neoplastic agent due to their porous nature. Also, they have well-defined crystalline structures that can be characterized by different analytical techniques and their sizes are suitable to control their in vivo drug release.

Metal-organic frameworks (MOFs) are promising new nanocarriers with potential use in anticancer drug delivery. However, there is a scarcity of studies on the uptake and release of guest molecules associated with MOF nanovehicles, and their mechanism is poorly understood. In this work, newly developed iron-based MOFs, namely Fe-NDC nanorods, were investigated as potential nanocarriers for calcein (as a model drug/dye) and Doxorubicin (a chemotherapeutic drug (DOX)). Calcein was successfully loaded by equilibrating its solution with the MOFs nanoparticles under constant stirring. The calcein average encapsulation efficiency achieved was 43.13%, with a corresponding capacity of 17.74 wt.%. In-vitro calcein release was then carried out at 37 °C in phosphate buffer saline (PBS) using ultrasound (US) as an external trigger. MOFs released an average of 17.8% (without US), whereas they released up to 95.2% of their contents when 40-kHz US at ∼1 W/cm² was applied for 10 min. The cytostatic drug DOX was also encapsulated in Fe-NDC, and its In-vitro release profile was determined under the same conditions. DOX encapsulation efficiency and capacity were found to be 16.10% and 13.37 wt.%, respectively. In-vitro release experiments demonstrated significant release, reaching 80% in 245 minutes, under acoustic irradiation, compared to around 6% in the absence of US. Additionally, experimental results showed that Fe-NDC nanoparticles are biocompatible even at relatively high concentrations, with an MCF-7 IC₅₀ of 1022 μg/ml. Our work provides a promising platform for anticancer drug delivery by utilizing biocompatible Fe-NDC nanoparticles and US as an external trigger mechanism.

The adsorption process of the cationic dye Malachite Green (MG) and the anionic dye Methyl Orange (MO) onto a MOF, namely, MIL-53(Al) was studied under several experimental parameters. Batch experiments were performed to investigate the feasibility of this MOF as possible adsorbent for the removal of MG and MO from both single and binary-dye aqueous solutions. Experimental results revealed that MIL-53(Al) can quickly bind to both types of dyes with high removal efficiency of more than 95%. The effects of different parameters such as adsorbent dosage, initial concentration of dye solution, pH of the solution, and temperature on the adsorption process were examined. Adsorption kinetic data were then fitted using pseudo first-order, pseudo second-order, and elovich models, showing that pseudo second-order model had the best fit for both dyes among the other models in both single and binary-dye systems with R2>0.996. Moreover, adsorption isotherm models of Langmuir and Freundlich were studied and the isotherm data was found to be in good agreement with the Freundlich isotherm for both dyes. Thermodynamics studies of change in Gibbs free energy, enthalpy, and entropy were carried out and showed that the adsorption of both dyes was endothermic and spontaneous. The selectivity test for an equimolar binary-dye solution containing both MG and MO suggested the higher affinity of MIL-53(Al) towards MO over MG, as it reached a value of 13.58 at the optimum conditions. Finally, excellent reusability of MIL-53(Al) was shown by utilizing it for 4 cycles of adsorption-desorption with almost no reduction in the adsorption capacity, bringing about additional examination of its applicability.

Metal halide perovskites (MHPs) have excellent optoelectronic and photovoltaic applications because of their cost-effectiveness, tunable emission, high photoluminescence quantum yields, and excellent charge carrier properties. However, the potential applications of the entire MHP family are facing a major challenge arising from its weak resistance to moisture, polar solvents, temperature, and light exposure. A viable strategy to enhance the stability of MHPs could lie in their incorporation into a porous template. Metal-organic frameworks (MOFs) have outstanding properties, with a unique network of ordered/functional pores, which render them promising for functioning as such a template, accommodating a wide range of MHPs to the nanosized region, alongside minimizing particle aggregation and enhancing the stability of the entrapped species. This review highlights recent advances in design strategies, synthesis, characterization, and properties of various hybrids of MOFs with MHPs. Particular attention is paid to a critical review of the emergence of MHP@MOF for comprehensive studies of next-generation materials for various technological applications including sensors, photocatalysis, encryption/decryption, light-emitting diodes, and solar cells. Finally, by summarizing the state-of-the-art, some promising future applications of reported hybrids are proposed. Considering the inherent correlation and synergic functionalities of MHPs and MOFs, further advancement; new functional materials; and applications can be achieved through designing MHP@MOF hybrids.

Climate change due to anthropogenic carbon dioxide emissions (e.g., combustion of fossil fuels) represents one of the most profound environmental disasters of this century. According to the Special Report completed by Intergovernmental Panel on Climate Change (IPCC) in October 2018, maintaining global warming at 1.5 Celsius degree requires a reduction in CO2 emissions of 49% by 2030. To meet this urgent target, power plants have to equip with carbon capture and storage (CCS) technology. For postcombustion CO2 capture from flue gas, there are four main challenges: (1) the low pressure (ca. 1 bar) of the flue gas produced by power plants; (2) the lower CO2 concentration (15-16%) of flue gas; (3) a high CO2 removal requirement (50-90%); and (4) a low energy consumption of the applied technology. Membrane-based CO2 separation is an attractive technology that meets many of the requirements for economic postcombustion CO2 capture. Within this field, thin-film composite (TFC) membranes are particular attractive due to their high gas permeance. TFC membranes are usually composed of three layers: (1) a bottom porous support layer to provide mechanical strength; (2) a top thin (<1 micrometer) species-selective layer to provide selective function; and (3) a highly permeable intermediate gutter layer to improve the compatibility between the support layer and selective layer. Currently, a key challenge in the development of high performance TFC membranes has been to simultaneously maximize the transmembrane gas permeance (by minimizing the gas permeation resistance of each layer) while maintaining high gas pair selectivities. Two-dimensional (2D) nanosheets are recognized as promising candidates for preparing highly permeable and selective membranes by virtue of their nanosized thickness along with their regular in-plane or interlayer pore arrays, providing minimum transport resistance and maximum selectivity based on the molecular size or solubility. In this thesis, based on 2D

Shaping metal-organic frameworks (MOFs) into robust particles with a controllable size is of large interest to the field of adsorption. Therefore, a method is presented here to produce robust MOF beads of different sizes, ranging from 250 μm to several millimeters, which, moreover, preserve the adsorption properties of the unformulated MOF. A simple, mild, and flexible method is demonstrated with the zeolitic imidazolate framework-8 (ZIF-8)/polyvinyl formal composite material. The properties of the composite material are determined via optical imaging, scanning electron microscopy, energy-dispersive X-ray spectroscopy, inductively coupled plasma mass spectrometry, X-ray diffraction, mercury intrusion, argon porosimetry and pycnometry as well as thermogravimetric analysis/differential scanning calorimetry, crush strength tests, and immersion experiments. The proposed method allows the production of resistant particles with a high MOF loading (up to 85 wt %) and remarkable structural and textural properties required for adsorptive separation processes, including a preserved ZIF-8 crystalline structure, microporosity, and a narrow macropore size distribution (1.27 μm average). The particles show a spherical shape with an average aspect ratio of 0.85. The stability tests demonstrated that the composite MOF material exhibits a high mechanical strength (3.09 N/Pc crushing strength) almost equivalent to that of a widely used commercial zeolite material. Furthermore, the material remains stable up to 200 °C and in most solvents. The adsorption properties are explored via static and dynamic experiments in the vapor and liquid phases. The results show that the adsorption capacities are only reduced in proportion to the binder content compared with the pristine material, indicating no binder intrusion in the ZIF-8 pores. Fixed-bed experiments demonstrate the remarkable separation performance in the vapor phase, whereas mass transfer limitations arise in the liquid phase with i, SCOPUS: ar.j, info:eu-repo/semantics/published

For practical applications Cu(I) π-complexation adsorption demands both a high performance and a good stability. In this work, we simultaneously incorporated copper and vanadium into a typical metal–organic framework (MOF) of MIL-101. Thanks to the assistance of V, selective reduction of Cu(II) to Cu(I) was efficiently realized at a low temperature of 250 °C. Compared with the common reduction temperature of over 450 °C, the temperature in this work was dramatically reduced. The low temperature can guarantee the structural integrity of the MIL-101 support during the reduction procedure, since the structure of MIL-101 will collapse at or over 300 °C. We also demonstrated that the resulting CuVM adsorbents exhibited superior performances to those of pristine MIL-101 on CO separation from N2 and H2 mixtures, in terms of both the capacity and the selectivity. The utmost capacity of 29.2 cm3·g–1 at 100 kPa for CO adsorption was achieved on 2.5CuVM, which significantly surpassed the capacity on MIL-101 (12.2 cm3·g–1). With regards to the selectivity, 2.5CuVM showed a much better performance than MIL-101 as well, with that of 70.1 for CO/N2 and 641.7 for CO/H2. Moreover, in traditional π-complexation adsorbents, Cu(I) was easily oxidized to Cu(II) and thus lost the activity. In this study, the cuprous sites on 2.5CuVM material showed a remarkable oxygen-resistant ability under exposure to atmospheric air for about 2 weeks. This study provides a new avenue for the design and fabrication of Cu(I) π-complexation adsorbents with both high performances and excellent oxygen resistance.

Enhanced CO2 Capture in Metal-Organic and Covalent-Organic FrameworksbyRobinson W FlaigDoctor of Philosophy in ChemistryUniversity of California, BerkeleyProfessor Omar Yaghi, ChairGlobal atmospheric carbon dioxide (CO2) levels are rising. It is widely acknowledged by the scientific community that this phenomenon is contributing to climate change. Therefore, the need for effective CO2 capture from both point sources (power plants, etc.) and direct air capture is urgent. Despite years of investigation, the development of scalable, cost-effective, and energy-efficient, carbon capture and sequestration (CCS) technologies remains an outstanding challenge. The most widely- employed technique to date is the use of aqueous monoethanolamine (MEA) solutions at CO2 point sources. Flue gas from point sources is pumped through these solutions which capture the CO2 by forming chemical bonds (e.g. ammonium carbamate formation) between the gas and the amine moieties in solution. Although a large amount of CO2 can be captured using this technology, it is energetically inefficient. With one of the highest specific heat capacities among common solvents, water requires a significant amount of energy to bring to temperatures at which the MEA molecules release the previously- captured CO2. The requisite energy is often produced at similar CO2-producing point sources, limiting the effectiveness of this technique when employed.For this reason and others, (e.g. instability of aqueous MEA solutions to other contaminants present in flue gas) many are considering alternative methods of CO2 capture from point sources. One particularly potent method involves the use of amine- functionalized porous adsorbents in an analogous fashion to MEA solutions, as these materials frequently exhibit lower heat capacities, higher selectivities, and greater chemical tunability compared to their liquid-based counterparts.Reticular chemistry, the process of assembling judiciously designed rigid molecula

Enhanced CO2 Capture in Metal-Organic and Covalent-Organic FrameworksbyRobinson W FlaigDoctor of Philosophy in ChemistryUniversity of California, BerkeleyProfessor Omar Yaghi, ChairGlobal atmospheric carbon dioxide (CO2) levels are rising. It is widely acknowledged by the scientific community that this phenomenon is contributing to climate change. Therefore, the need for effective CO2 capture from both point sources (power plants, etc.) and direct air capture is urgent. Despite years of investigation, the development of scalable, cost-effective, and energy-efficient, carbon capture and sequestration (CCS) technologies remains an outstanding challenge. The most widely- employed technique to date is the use of aqueous monoethanolamine (MEA) solutions at CO2 point sources. Flue gas from point sources is pumped through these solutions which capture the CO2 by forming chemical bonds (e.g. ammonium carbamate formation) between the gas and the amine moieties in solution. Although a large amount of CO2 can be captured using this technology, it is energetically inefficient. With one of the highest specific heat capacities among common solvents, water requires a significant amount of energy to bring to temperatures at which the MEA molecules release the previously- captured CO2. The requisite energy is often produced at similar CO2-producing point sources, limiting the effectiveness of this technique when employed.For this reason and others, (e.g. instability of aqueous MEA solutions to other contaminants present in flue gas) many are considering alternative methods of CO2 capture from point sources. One particularly potent method involves the use of amine- functionalized porous adsorbents in an analogous fashion to MEA solutions, as these materials frequently exhibit lower heat capacities, higher selectivities, and greater chemical tunability compared to their liquid-based counterparts.Reticular chemistry, the process of assembling judiciously designed rigid molecula

Electrospray ionization mass spectrometry (ESI-MS) has been utilized to investigate the self-assembly processes occurring during the formation of the microporous metal–organic framework CPO-27-M (M = Co, Ni). The mono- and dinuclear building units {M(Hxdhtp)} and {M2(Hxdhtp)}, where Hxdhtp is the organic linker HxC8O6 and fragments thereof, were identified as key species present in the reaction mixture during the product formation. Time-resolved powder X-ray diffraction analysis was used to follow the synthesis and confirmed that no other crystalline products occur in the reaction mixture prior to the crystallization of CPO-27-Ni. When equimolar reactions were performed at room temperature, compounds [(M(H2dhtp)(H2O)4·2H2O] (M = Co, Ni) crystallized instead of CPO-27 obtained at the higher temperature of the solvothermal procedure. It was confirmed that mono- and dinuclear species are key building blocks not only in the formation of CPO-27-M but also in the formation of the 1D chain structure (M(H2dhtp)(H2O)4) obtained from these room-temperature reactions.

In the Stockholm convention, perfluoroalkyl substances (PFASs), such as perfluorooctanoic acid (PFOA), are considered one of the most prevalent persistent organic pollutants and readily bioaccumulate. The most widely used method for PFAS analysis is liquid chromatography tandem mass spectrometry (LC-MS). However, MS based methods are time consuming, require significant instrumentation, and must be performed in a laboratory that is often hours from the site of contamination. Metal-organic frameworks (MOFs) are materials composed of organic linkers that form frameworks by binding to metal ions in a crystal lattice, they have unique properties such as high porosity, tunability and large surface areas. Here, we developed a novel ionization approach in which a MOF material was immobilized on microneedles for the extraction of PFOA directly from water samples for rapid analysis by MS in 3 minutes at trace levels. These MOFs coated SPME probes were characterised using Scanning electron microscopy (SEM), Energy dispersive X-ray (EDS), Small angle X-ray Scattering (SAXS) and Brunauer-Emmett-Teller (BET) techniques. We proved that PFOA molecules are adsorbed onto MOF pores by observing a decrease in surface area using a BET approach. Furthermore, we modelled the interaction between PFOA molecules and different types of metal organic frameworks (MOFs) using DFT calculations to understand how the surface areas of MOFs and the intermolecular interactions play an important role in capturing such an analyte, PFOA. Out of four MOFs (ZIF-8, Tb2(BDC)3, MIL-88A, and UiO-66) investigated, the most promising surface coating for direct and rapid PFOA analysis was ZIF-8, based on MS results. The limit of detection (LOD) of PFOA in Milli-Q water by the use of a ZIF-8 coated microneedle ion emitter was calculated to be approximately 26.6 ± 6.1 ppt level. Finally, we have shown that a ZIF-8 ion emitter can be used to measure the concentration of PFOA in an environmental water and obtained a

Heterogeneous single-site catalysts consist of isolated, well-defined, active sites that are spatially separated in a given solid and, ideally, structurally identical. In this review, the potential of metal–organic frameworks (MOFs) and covalent organic frameworks (COFs) as platforms for the development of heterogeneous single-site catalysts is reviewed thoroughly. In the first part of this article, synthetic strategies and progress in the implementation of such sites in these two classes of materials are discussed. Because these solids are excellent playgrounds to allow a better understanding of catalytic functions, we highlight the most important recent advances in the modelling and spectroscopic characterization of single-site catalysts based on these materials. Finally, we discuss the potential of MOFs as materials in which several single-site catalytic functions can be combined within one framework along with their potential as powerful enzyme-mimicking materials. The review is wrapped up with our personal vision on future research directions.

This final degree paper is based on the photochemical characterization of MIL-125 (TI) MOFs in order to study the photogeneration of the charge separation state for its possible application as photoactive material in optoelectronic devices. An amino group has been introduced into the organic ligand of the MOF and the PEDOT polymer has been incorporated for the purpose of increasing its absorption in the visible range. On the other hand, with the incorporation of PEDOT as a conductive element, it is intended to increase the time of the photogenerated charge separation state after the laser excitation. The ultimate goal is to increase the lifetime of the material to act as a semiconductor in solar cells., El presente trabajo fin de grado se basa en la caracterización fotoquímica de los MOFs tipo MIL-125(TI) con la finalidad de estudiar la fotogeneración del estado de separación de cargas para su posible aplicación como material fotoactivo en dispositivos optoelectrónicos. Se ha introducido un grupo amino en el ligando orgánico del MOF y se ha incorporado el polímero PEDOT con el propósito de aumentar su absorción en el rango visible. Por otro lado, con la incorporación de PEDOT como elemento conductor, se pretende aumentar el tiempo del estado de separación de cargas fotogenerado tras la excitación con láser. El objetivo final es aumentar el tiempo de vida útil del material para actuar como semiconductor en celdas solares., El present treball fi de grau, es basa en la caracterització fotoquímica dels MOFs tipus MIL- 125(TI) amb la finalitat d’estudiar la fotogeneració de l’estat de separació de càrregues per a la seva possible aplicació en dispositius optoelectrònics. S’ha introduït un grup amino en el lligand orgànic del MOF i s’ha incorporat el polímerPEDOT amb el propòsit d’augmentarl’absorció en l’interval visible. D’altra banda, amb la incorporació de PEDOT com un element conductor, es pretén augmentar el temps de l’estat de separació de càrregues fotogenerat després de l’excitació amb làser. L’objectiu final és augmentar el temps de vida útil del material per actuar com a semiconductor en cèl·lules solars.

This final degree paper is based on the photochemical characterization of MIL-125 (TI) MOFs in order to study the photogeneration of the charge separation state for its possible application as photoactive material in optoelectronic devices. An amino group has been introduced into the organic ligand of the MOF and the PEDOT polymer has been incorporated for the purpose of increasing its absorption in the visible range. On the other hand, with the incorporation of PEDOT as a conductive element, it is intended to increase the time of the photogenerated charge separation state after the laser excitation. The ultimate goal is to increase the lifetime of the material to act as a semiconductor in solar cells., El presente trabajo fin de grado se basa en la caracterización fotoquímica de los MOFs tipo MIL-125(TI) con la finalidad de estudiar la fotogeneración del estado de separación de cargas para su posible aplicación como material fotoactivo en dispositivos optoelectrónicos. Se ha introducido un grupo amino en el ligando orgánico del MOF y se ha incorporado el polímero PEDOT con el propósito de aumentar su absorción en el rango visible. Por otro lado, con la incorporación de PEDOT como elemento conductor, se pretende aumentar el tiempo del estado de separación de cargas fotogenerado tras la excitación con láser. El objetivo final es aumentar el tiempo de vida útil del material para actuar como semiconductor en celdas solares., El present treball fi de grau, es basa en la caracterització fotoquímica dels MOFs tipus MIL- 125(TI) amb la finalitat d’estudiar la fotogeneració de l’estat de separació de càrregues per a la seva possible aplicació en dispositius optoelectrònics. S’ha introduït un grup amino en el lligand orgànic del MOF i s’ha incorporat el polímerPEDOT amb el propòsit d’augmentarl’absorció en l’interval visible. D’altra banda, amb la incorporació de PEDOT com un element conductor, es pretén augmentar el temps de l’estat de separació de càrregues fotogenerat després de l’excitació amb làser. L’objectiu final és augmentar el temps de vida útil del material per actuar com a semiconductor en cèl·lules solars.

Heterogeneous single-site catalysts consist of isolated, well-defined, active sites that are spatially separated in a given solid and, ideally, structurally identical. In this review, the potential of metal–organic frameworks (MOFs) and covalent organic frameworks (COFs) as platforms for the development of heterogeneous single-site catalysts is reviewed thoroughly. In the first part of this article, synthetic strategies and progress in the implementation of such sites in these two classes of materials are discussed. Because these solids are excellent playgrounds to allow a better understanding of catalytic functions, we highlight the most important recent advances in the modelling and spectroscopic characterization of single-site catalysts based on these materials. Finally, we discuss the potential of MOFs as materials in which several single-site catalytic functions can be combined within one framework along with their potential as powerful enzyme-mimicking materials. The review is wrapped up with our personal vision on future research directions.

This final degree paper is based on the photochemical characterization of MIL-125 (TI) MOFs in order to study the photogeneration of the charge separation state for its possible application as photoactive material in optoelectronic devices. An amino group has been introduced into the organic ligand of the MOF and the PEDOT polymer has been incorporated for the purpose of increasing its absorption in the visible range. On the other hand, with the incorporation of PEDOT as a conductive element, it is intended to increase the time of the photogenerated charge separation state after the laser excitation. The ultimate goal is to increase the lifetime of the material to act as a semiconductor in solar cells., El presente trabajo fin de grado se basa en la caracterización fotoquímica de los MOFs tipo MIL-125(TI) con la finalidad de estudiar la fotogeneración del estado de separación de cargas para su posible aplicación como material fotoactivo en dispositivos optoelectrónicos. Se ha introducido un grupo amino en el ligando orgánico del MOF y se ha incorporado el polímero PEDOT con el propósito de aumentar su absorción en el rango visible. Por otro lado, con la incorporación de PEDOT como elemento conductor, se pretende aumentar el tiempo del estado de separación de cargas fotogenerado tras la excitación con láser. El objetivo final es aumentar el tiempo de vida útil del material para actuar como semiconductor en celdas solares., El present treball fi de grau, es basa en la caracterització fotoquímica dels MOFs tipus MIL- 125(TI) amb la finalitat d’estudiar la fotogeneració de l’estat de separació de càrregues per a la seva possible aplicació en dispositius optoelectrònics. S’ha introduït un grup amino en el lligand orgànic del MOF i s’ha incorporat el polímerPEDOT amb el propòsit d’augmentarl’absorció en l’interval visible. D’altra banda, amb la incorporació de PEDOT com un element conductor, es pretén augmentar el temps de l’estat de separació de càrregues fotogenerat després de l’excitació amb làser. L’objectiu final és augmentar el temps de vida útil del material per actuar com a semiconductor en cèl·lules solars.

This final degree paper is based on the photochemical characterization of MIL-125 (TI) MOFs in order to study the photogeneration of the charge separation state for its possible application as photoactive material in optoelectronic devices. An amino group has been introduced into the organic ligand of the MOF and the PEDOT polymer has been incorporated for the purpose of increasing its absorption in the visible range. On the other hand, with the incorporation of PEDOT as a conductive element, it is intended to increase the time of the photogenerated charge separation state after the laser excitation. The ultimate goal is to increase the lifetime of the material to act as a semiconductor in solar cells., El presente trabajo fin de grado se basa en la caracterización fotoquímica de los MOFs tipo MIL-125(TI) con la finalidad de estudiar la fotogeneración del estado de separación de cargas para su posible aplicación como material fotoactivo en dispositivos optoelectrónicos. Se ha introducido un grupo amino en el ligando orgánico del MOF y se ha incorporado el polímero PEDOT con el propósito de aumentar su absorción en el rango visible. Por otro lado, con la incorporación de PEDOT como elemento conductor, se pretende aumentar el tiempo del estado de separación de cargas fotogenerado tras la excitación con láser. El objetivo final es aumentar el tiempo de vida útil del material para actuar como semiconductor en celdas solares., El present treball fi de grau, es basa en la caracterització fotoquímica dels MOFs tipus MIL- 125(TI) amb la finalitat d’estudiar la fotogeneració de l’estat de separació de càrregues per a la seva possible aplicació en dispositius optoelectrònics. S’ha introduït un grup amino en el lligand orgànic del MOF i s’ha incorporat el polímerPEDOT amb el propòsit d’augmentarl’absorció en l’interval visible. D’altra banda, amb la incorporació de PEDOT com un element conductor, es pretén augmentar el temps de l’estat de separació de càrregues fotogenerat després de l’excitació amb làser. L’objectiu final és augmentar el temps de vida útil del material per actuar com a semiconductor en cèl·lules solars.

Here we report the use of a pillaring strategy for the design and synthesis of three novel amide-functionalized metal–organic frameworks (MOFs), TMUs-22/-23/-24, isoreticular to the recently reported imine-functionalized TMU-6 and TMU-21 MOFs. An extensive study of their CO2 sorption properties and selectivity for CO2 over N2, from single gas sorption isotherms to breakthrough measurements, revealed that not only the incorporation of amide groups but also their accessibility is crucial to obtain enhanced CO2 sorption and CO2/N2 selectivity. Therefore, the MOF with more accessible amide groups (TMU-24) shows a CO2/N2 selectivity value of ca. 10 (as revealed by breakthrough experiments), which is ca. 500% and 700% of the selectivity values observed for the other amide-containing (TMU-22 and TMU-23) and imine-containing (TMU-6 and TMU-21) MOFs.

The presence of a highly tunable porous structure and surface chemistry makes metal–organic framework (MOF) materials excellent candidates for artificial methane hydrate formation under mild temperature and pressure conditions (2 °C and 3–5 MPa). Experimental results using MOFs with a different pore structure and chemical nature (MIL-100 (Fe) and ZIF-8) clearly show that the water–framework interactions play a crucial role in defining the extent and nature of the gas hydrates formed. Whereas the hydrophobic MOF promotes methane hydrate formation with a high yield, the hydrophilic one does not. The formation of these methane hydrates on MOFs has been identified for the first time using inelastic neutron scattering (INS) and synchrotron X-ray powder diffraction (SXRPD). The results described in this work pave the way towards the design of new MOF structures able to promote artificial methane hydrate formation upon request (confined or non-confined) and under milder conditions than in nature.

Here we report the use of a pillaring strategy for the design and synthesis of three novel amide-functionalized metal–organic frameworks (MOFs), TMUs-22/-23/-24, isoreticular to the recently reported imine-functionalized TMU-6 and TMU-21 MOFs. An extensive study of their CO2 sorption properties and selectivity for CO2 over N2, from single gas sorption isotherms to breakthrough measurements, revealed that not only the incorporation of amide groups but also their accessibility is crucial to obtain enhanced CO2 sorption and CO2/N2 selectivity. Therefore, the MOF with more accessible amide groups (TMU-24) shows a CO2/N2 selectivity value of ca. 10 (as revealed by breakthrough experiments), which is ca. 500% and 700% of the selectivity values observed for the other amide-containing (TMU-22 and TMU-23) and imine-containing (TMU-6 and TMU-21) MOFs.

The presence of a highly tunable porous structure and surface chemistry makes metal–organic framework (MOF) materials excellent candidates for artificial methane hydrate formation under mild temperature and pressure conditions (2 °C and 3–5 MPa). Experimental results using MOFs with a different pore structure and chemical nature (MIL-100 (Fe) and ZIF-8) clearly show that the water–framework interactions play a crucial role in defining the extent and nature of the gas hydrates formed. Whereas the hydrophobic MOF promotes methane hydrate formation with a high yield, the hydrophilic one does not. The formation of these methane hydrates on MOFs has been identified for the first time using inelastic neutron scattering (INS) and synchrotron X-ray powder diffraction (SXRPD). The results described in this work pave the way towards the design of new MOF structures able to promote artificial methane hydrate formation upon request (confined or non-confined) and under milder conditions than in nature.

A set of terms, definitions, and recommendations is provided for use in the classification of coordination polymers, networks, and metal–organic frameworks (MOFs). A hierarchical terminology is recommended in which the most general term is coordination polymer. Coordination networks are a subset of coordination polymers and MOFs a further subset of coordination networks. One of the criteria an MOF needs to fulfill is that it contains potential voids, but no physical measurements of porosity or other properties are demanded per se. The use of topology and topology descriptors to enhance the description of crystal structures of MOFs and 3D-coordination polymers is furthermore strongly recommended.

A set of terms, definitions, and recommendations is provided for use in the classification of coordination polymers, networks, and metal–organic frameworks (MOFs). A hierarchical terminology is recommended in which the most general term is coordination polymer. Coordination networks are a subset of coordination polymers and MOFs a further subset of coordination networks. One of the criteria an MOF needs to fulfill is that it contains potential voids, but no physical measurements of porosity or other properties are demanded per se. The use of topology and topology descriptors to enhance the description of crystal structures of MOFs and 3D-coordination polymers is furthermore strongly recommended.

Coordination polymers (CPs) and metal–organic frameworks (MOFs) are among the most prolific research areas of inorganic chemistry and crystal engineering in the last 15 years, and yet it still seems that consensus is lacking about what they really are, or are not.

Coordination polymers (CPs) and metal–organic frameworks (MOFs) are among the most prolific research areas of inorganic chemistry and crystal engineering in the last 15 years, and yet it still seems that consensus is lacking about what they really are, or are not.

Samouspořádávání je proces spontánního uspořádávání molekul do definovaných supra-molekulárních struktur na površích. Organické molekuly vykazující schopnost samouspořádání mohou být použity jako stavební prvky pro výrobu struktur přístupem "bottom-up", který umožňuje syntézu atomárně přesných dvourozměrných (2D) struktur. Začleníme-li do molekulárního uspořádání atomy kovu může dojít k vytvoření 2D sítí organika-kov (2D MOF). Atomy kovu jsou v nich periodicky uspořádány díky organickým molekulám, které je vzájemě spojují. Takovéto struktury na povrchu materiálů mohou vést k zajímavým vlastnostem, např. změně elektrických vlastností materiálů, nebo použítí nových exotických stavů hmoty v technologických zařízeních. Tato práce se zabývá studiem struktur na bázi karbonitrilových molekul a atomů přechodných kovů na povrchu ušlechtilých kovů a topologického izolantu. Vybrané molekuly, u nichž budeme studovat možnosti využití jako ligandu, jsou HATCN a DCA. Práce představuje výsledky z metod LEEM a STM pro molekulární samouspořádání na obou typech povrchů, a pro systémy organika-kov jen na ušlechtilých kovech; zejména DCA se ukazuje jako slibná molekula pro tvorbu 2D MOFs. Úspěšně jsme vytvořili periodicky uspořádané MOF s atomy Fe na povrchu Ag(111) a molekulární samouspořádání DCA molekul na povrchu Bi2Se3., Molecular self-assembly is a spontaneous association of molecules into well-defined supra-molecular structures on surfaces. Organic molecules exhibiting self-assembly can act as building blocks at the nanoscale and allow for a bottom-up synthesis of atomically precise arrangements, e.g., two-dimensional (2D) nanoarrays. The incorporation of metal atoms leads to the formation of a 2D metal-organic framework (2D MOF). Therein, embedded (magnetic) metal atoms are arranged in a periodic way, linked by organic linker units. At the surface of a material, this holds powerful opportunities, e.g., to change the electronic properties of a material or enable the usage of exotic new states of matter in device technology. This thesis studies assembled structures of carbonitrile molecules and transitional metal atoms on coinage metal and topological insulator surfaces. The molecules HATCN and DCA are tested as suitable candidates for organic linker units. We present especially LEEM and STM results for molecular self-assembly on both types of surfaces and for the metal-organic structure formation on coinage metals. In particular, the DCA molecules show high potential as a linker. We successfully formed a long-range ordered MOF with Fe atoms on the Ag(111) surface and a molecular self-assembly was observed for DCA deposited on Bi2Se3.

Samouspořádávání je proces spontánního uspořádávání molekul do definovaných supra-molekulárních struktur na površích. Organické molekuly vykazující schopnost samouspořádání mohou být použity jako stavební prvky pro výrobu struktur přístupem "bottom-up", který umožňuje syntézu atomárně přesných dvourozměrných (2D) struktur. Začleníme-li do molekulárního uspořádání atomy kovu může dojít k vytvoření 2D sítí organika-kov (2D MOF). Atomy kovu jsou v nich periodicky uspořádány díky organickým molekulám, které je vzájemě spojují. Takovéto struktury na povrchu materiálů mohou vést k zajímavým vlastnostem, např. změně elektrických vlastností materiálů, nebo použítí nových exotických stavů hmoty v technologických zařízeních. Tato práce se zabývá studiem struktur na bázi karbonitrilových molekul a atomů přechodných kovů na povrchu ušlechtilých kovů a topologického izolantu. Vybrané molekuly, u nichž budeme studovat možnosti využití jako ligandu, jsou HATCN a DCA. Práce představuje výsledky z metod LEEM a STM pro molekulární samouspořádání na obou typech povrchů, a pro systémy organika-kov jen na ušlechtilých kovech; zejména DCA se ukazuje jako slibná molekula pro tvorbu 2D MOFs. Úspěšně jsme vytvořili periodicky uspořádané MOF s atomy Fe na povrchu Ag(111) a molekulární samouspořádání DCA molekul na povrchu Bi2Se3., Molecular self-assembly is a spontaneous association of molecules into well-defined supra-molecular structures on surfaces. Organic molecules exhibiting self-assembly can act as building blocks at the nanoscale and allow for a bottom-up synthesis of atomically precise arrangements, e.g., two-dimensional (2D) nanoarrays. The incorporation of metal atoms leads to the formation of a 2D metal-organic framework (2D MOF). Therein, embedded (magnetic) metal atoms are arranged in a periodic way, linked by organic linker units. At the surface of a material, this holds powerful opportunities, e.g., to change the electronic properties of a material or enable the usage of exotic new states of matter in device technology. This thesis studies assembled structures of carbonitrile molecules and transitional metal atoms on coinage metal and topological insulator surfaces. The molecules HATCN and DCA are tested as suitable candidates for organic linker units. We present especially LEEM and STM results for molecular self-assembly on both types of surfaces and for the metal-organic structure formation on coinage metals. In particular, the DCA molecules show high potential as a linker. We successfully formed a long-range ordered MOF with Fe atoms on the Ag(111) surface and a molecular self-assembly was observed for DCA deposited on Bi2Se3.

Samouspořádávání je proces spontánního uspořádávání molekul do definovaných supra-molekulárních struktur na površích. Organické molekuly vykazující schopnost samouspořádání mohou být použity jako stavební prvky pro výrobu struktur přístupem "bottom-up", který umožňuje syntézu atomárně přesných dvourozměrných (2D) struktur. Začleníme-li do molekulárního uspořádání atomy kovu může dojít k vytvoření 2D sítí organika-kov (2D MOF). Atomy kovu jsou v nich periodicky uspořádány díky organickým molekulám, které je vzájemě spojují. Takovéto struktury na povrchu materiálů mohou vést k zajímavým vlastnostem, např. změně elektrických vlastností materiálů, nebo použítí nových exotických stavů hmoty v technologických zařízeních. Tato práce se zabývá studiem struktur na bázi karbonitrilových molekul a atomů přechodných kovů na povrchu ušlechtilých kovů a topologického izolantu. Vybrané molekuly, u nichž budeme studovat možnosti využití jako ligandu, jsou HATCN a DCA. Práce představuje výsledky z metod LEEM a STM pro molekulární samouspořádání na obou typech povrchů, a pro systémy organika-kov jen na ušlechtilých kovech; zejména DCA se ukazuje jako slibná molekula pro tvorbu 2D MOFs. Úspěšně jsme vytvořili periodicky uspořádané MOF s atomy Fe na povrchu Ag(111) a molekulární samouspořádání DCA molekul na povrchu Bi2Se3., Molecular self-assembly is a spontaneous association of molecules into well-defined supra-molecular structures on surfaces. Organic molecules exhibiting self-assembly can act as building blocks at the nanoscale and allow for a bottom-up synthesis of atomically precise arrangements, e.g., two-dimensional (2D) nanoarrays. The incorporation of metal atoms leads to the formation of a 2D metal-organic framework (2D MOF). Therein, embedded (magnetic) metal atoms are arranged in a periodic way, linked by organic linker units. At the surface of a material, this holds powerful opportunities, e.g., to change the electronic properties of a material or enable the usage of exotic new states of matter in device technology. This thesis studies assembled structures of carbonitrile molecules and transitional metal atoms on coinage metal and topological insulator surfaces. The molecules HATCN and DCA are tested as suitable candidates for organic linker units. We present especially LEEM and STM results for molecular self-assembly on both types of surfaces and for the metal-organic structure formation on coinage metals. In particular, the DCA molecules show high potential as a linker. We successfully formed a long-range ordered MOF with Fe atoms on the Ag(111) surface and a molecular self-assembly was observed for DCA deposited on Bi2Se3.

Samouspořádávání je proces spontánního uspořádávání molekul do definovaných supra-molekulárních struktur na površích. Organické molekuly vykazující schopnost samouspořádání mohou být použity jako stavební prvky pro výrobu struktur přístupem "bottom-up", který umožňuje syntézu atomárně přesných dvourozměrných (2D) struktur. Začleníme-li do molekulárního uspořádání atomy kovu může dojít k vytvoření 2D sítí organika-kov (2D MOF). Atomy kovu jsou v nich periodicky uspořádány díky organickým molekulám, které je vzájemě spojují. Takovéto struktury na povrchu materiálů mohou vést k zajímavým vlastnostem, např. změně elektrických vlastností materiálů, nebo použítí nových exotických stavů hmoty v technologických zařízeních. Tato práce se zabývá studiem struktur na bázi karbonitrilových molekul a atomů přechodných kovů na povrchu ušlechtilých kovů a topologického izolantu. Vybrané molekuly, u nichž budeme studovat možnosti využití jako ligandu, jsou HATCN a DCA. Práce představuje výsledky z metod LEEM a STM pro molekulární samouspořádání na obou typech povrchů, a pro systémy organika-kov jen na ušlechtilých kovech; zejména DCA se ukazuje jako slibná molekula pro tvorbu 2D MOFs. Úspěšně jsme vytvořili periodicky uspořádané MOF s atomy Fe na povrchu Ag(111) a molekulární samouspořádání DCA molekul na povrchu Bi2Se3., Molecular self-assembly is a spontaneous association of molecules into well-defined supra-molecular structures on surfaces. Organic molecules exhibiting self-assembly can act as building blocks at the nanoscale and allow for a bottom-up synthesis of atomically precise arrangements, e.g., two-dimensional (2D) nanoarrays. The incorporation of metal atoms leads to the formation of a 2D metal-organic framework (2D MOF). Therein, embedded (magnetic) metal atoms are arranged in a periodic way, linked by organic linker units. At the surface of a material, this holds powerful opportunities, e.g., to change the electronic properties of a material or enable the usage of exotic new states of matter in device technology. This thesis studies assembled structures of carbonitrile molecules and transitional metal atoms on coinage metal and topological insulator surfaces. The molecules HATCN and DCA are tested as suitable candidates for organic linker units. We present especially LEEM and STM results for molecular self-assembly on both types of surfaces and for the metal-organic structure formation on coinage metals. In particular, the DCA molecules show high potential as a linker. We successfully formed a long-range ordered MOF with Fe atoms on the Ag(111) surface and a molecular self-assembly was observed for DCA deposited on Bi2Se3.

Samouspořádávání je proces spontánního uspořádávání molekul do definovaných supra-molekulárních struktur na površích. Organické molekuly vykazující schopnost samouspořádání mohou být použity jako stavební prvky pro výrobu struktur přístupem "bottom-up", který umožňuje syntézu atomárně přesných dvourozměrných (2D) struktur. Začleníme-li do molekulárního uspořádání atomy kovu může dojít k vytvoření 2D sítí organika-kov (2D MOF). Atomy kovu jsou v nich periodicky uspořádány díky organickým molekulám, které je vzájemě spojují. Takovéto struktury na povrchu materiálů mohou vést k zajímavým vlastnostem, např. změně elektrických vlastností materiálů, nebo použítí nových exotických stavů hmoty v technologických zařízeních. Tato práce se zabývá studiem struktur na bázi karbonitrilových molekul a atomů přechodných kovů na povrchu ušlechtilých kovů a topologického izolantu. Vybrané molekuly, u nichž budeme studovat možnosti využití jako ligandu, jsou HATCN a DCA. Práce představuje výsledky z metod LEEM a STM pro molekulární samouspořádání na obou typech povrchů, a pro systémy organika-kov jen na ušlechtilých kovech; zejména DCA se ukazuje jako slibná molekula pro tvorbu 2D MOFs. Úspěšně jsme vytvořili periodicky uspořádané MOF s atomy Fe na povrchu Ag(111) a molekulární samouspořádání DCA molekul na povrchu Bi2Se3., Molecular self-assembly is a spontaneous association of molecules into well-defined supra-molecular structures on surfaces. Organic molecules exhibiting self-assembly can act as building blocks at the nanoscale and allow for a bottom-up synthesis of atomically precise arrangements, e.g., two-dimensional (2D) nanoarrays. The incorporation of metal atoms leads to the formation of a 2D metal-organic framework (2D MOF). Therein, embedded (magnetic) metal atoms are arranged in a periodic way, linked by organic linker units. At the surface of a material, this holds powerful opportunities, e.g., to change the electronic properties of a material or enable the usage of exotic new states of matter in device technology. This thesis studies assembled structures of carbonitrile molecules and transitional metal atoms on coinage metal and topological insulator surfaces. The molecules HATCN and DCA are tested as suitable candidates for organic linker units. We present especially LEEM and STM results for molecular self-assembly on both types of surfaces and for the metal-organic structure formation on coinage metals. In particular, the DCA molecules show high potential as a linker. We successfully formed a long-range ordered MOF with Fe atoms on the Ag(111) surface and a molecular self-assembly was observed for DCA deposited on Bi2Se3.