abstract: We report the synthesis of novel boronic acid-containing metal-organic frameworks (MOFs), which was synthesized via solvothermal synthesis of cobalt nitride with 3,5-Dicarboxyphenylboronic acid (3,5-DCPBC). Powder X-ray diffraction and BET surface area analysis have been used to verify the successful synthesis of this microporous material. We have also made the attempts of using zinc nitride and copper nitride as metal sources to synthesize the boronic acid-containing MOFs. However, the attempts were not successful. The possible reason is the existence of copper and zinc ions catalyzed the decomposition of 3,5-Dicarboxyphenylboronic acid, forming isophthalic acid. The ended product has been proved to be isophthalic acid crystals by the single crystal X-ray diffraction. The effects of solvents, reaction temperature, and added bases were investigated. The addition of triethylamine has been shown to tremendously improve the sample crystallinity by facilitating ligand deprotonation / Dissertation/Thesis / Masters Thesis Chemical Engineering 2014

abstract: An urgent need for developing new chemical separations that address the capture of dilute impurities from fluid streams are needed. These separations include the capture of carbon dioxide from the atmosphere, impurities from drinking water, and toxins from blood streams. A challenge is presented when capturing these impurities because the energy cost for processing the bulk fluid stream to capture trace contaminants is too great using traditional thermal separations. The development of sorbents that may capture these contaminants passively has been emphasized in academic research for some time, producing many designer materials including metal-organic frameworks (MOFs) and polymeric resins. Scaffolds must be developed to effectively anchor these materials in a passing fluid stream. In this work, two design techniques are presented for anchoring these sorbents in electrospun fiber scaffolds. The first technique involves imbedding sorbent particles inside the fibers: forming particle-embedded fibers. It is demonstrated that particles will spontaneously coat themselves in the fibers at dilute loadings, but at higher loadings some get trapped on the fiber surface. A mathematical model is used to show that when these particles are embedded, the polymeric coating provided by the fibers may be designed to increase the kinetic selectivity and/or stability of the embedded sorbents. Two proof-of-concept studies are performed to validate this model including the increased selectivity of carbon dioxide over nitrogen when the MOF ZIF-8 is embedded in a poly(ethylene oxide) and Matrimid polymer blend; and that increased hydrothermal stability is realized when the water-sensitive MOF HKUST-1 is embedded in polystyrene fibers relative to pure HKUST-1 powder. The second technique involves the creation of a pore network throughout the fiber to increase accessibility of embedded sorbent particles. It is demonstrated that the removal of a blended highly soluble polymer additive from the spun particle-containing fibers leaves a pore network behind without removing the embedded sorbent. The increased accessibility of embedded sorbents is validated by embedding a known direct air capture sorbent in porous electrospun fibers, and demonstrating that they have the fastest kinetic uptake of any direct air capture sorbent reported in literature to date, along with over 90% sorbent accessibility. / Dissertation/Thesis / Doctoral Dissertation Chemical Engineering 2018

Thesis advisor: Jeffery A. Byers / Thesis advisor: Chia-Kuang Tsung / Homogeneous catalysts are advantageous in selective catalysis due to the well-defined active site at the molecular level. The poor recyclability, bimolecular aggregation, and undesired poison resistance of homogeneous catalysts hinder further industrial application despite the controlled reaction pathway due to the homogeneous environment. On the other hand, heterogeneous catalysts are preferred in industry due to their high recyclability and high activity. Yet, poor selectivity due to undefined active sites is a drawback. The construction of a host-guest system where a molecular level catalyst is incorporated into the Metal-Organic Framework (MOF) provides a promising solution to bridge those two fields. This composite maintains the advantages of homogeneous and heterogeneous catalysts and overcomes the disadvantages. However, finding an incorporation method that is versatile with minimum synthetic modification of the host and guest remains one of the challenges. In the first part of this dissertation, a new concept called “aperture-opening encapsulation’’ is introduced for incorporating large and diverse guest molecules into MOFs without changing the identity of either the guest or MOF. The approach capitalizes on the existence of linker exchange reactions, which, as our kinetic studies show, proceed via competition between associative and dissociative exchange mechanisms. The second part describes how this method is applied to incorporate a molecular catalyst into the cavity of UiO-66 for the hydrogenation of carbon dioxide to formate, which is a useful application for energy related industry. The developed hybrid composite showed the ability to be recycled, showed no evidence of bimolecular catalyst decomposition, and was less prone to catalyst poisoning. These results demonstrate for the first time how the aperture-opening process resulting from linker dissociation in MOFs can be utilized as a strategy to synthesize host-guest materials useful for chemical catalysis. After the establishment of the hybrid catalyst, the last part of the dissertation describes our efforts into the investigation of mass transport in catalysis. The understanding of the interaction between the host-guest is beneficial for the development of biological analogs in the future. / Thesis (PhD) — Boston College, 2019. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Chemistry.

No description available.

Industrial productions need the separation processes, but they are quite energyintensive, which occupy about half of the total energy consumption. Membranetechnology based on a non-thermal route is expected to reduce the associated energy duties by ~90%, but effective membrane materials capable of precisely isolating targeted species from complex mixtures are highly needed. Metal-organic frameworks (MOFs), possessing the tuneable pore size and geometry, are regarded as the promising platform for molecular separations and membrane design. This dissertation illustrates the rational design and the guided fabrication for various MOF membranes. Respectively, different gas separation applications were addressed by using these membranes, such as light hydrocarbon separations, carbon dioxide (CO2) captures and natural gas purifications. A versatile strategy for membrane fabrication is developed based on the electrochemical method. Following this, a family of face-centered cubic (fcu) MOF membranes were obtained, which possess different ligands and different clusters, namely rare-earth hexanuclear or zirconium hexanuclear clusters. Two MOF membranes based on fumarate (fum) linker, Zr-fum-fcu-MOF and Y-fum-fcu-MOF, showed efficient separation for the propylene/propane binary mixture, as well as the butane/isobutane equimolar mixtures, respectively. Further aperture editing applied to Zr-fum-fcu-MOF via mixed-linker approach permits the introduction of shape irregularity to the parent trefoil-shaped apertures, inducing an ideal shape-mismatch with tetrahedral CH4 molecules and blocking their transportation while affecting linear molecules slightly such as nitrogen (N2) and CO2. The resultant Zr-fum67-mesaconate (mes)33-MOF membranes exhibit great promise for natural gas purification, including efficient nitrogen rejection and simultaneous removal of CO2 and N2 from natural gas. In addition, a unique CO2-recognition membrane based on a fluorinated MOF (KAUST-7) is constructed for multipurpose CO2 capture, including CO2/H2, CO2/N2 and CO2/CH4 separation. The specific affinity to CO2 coupling with the molecular sieving capability of KAUST-7 enables the membrane to be nearly only permeable to CO2, excluding both smaller H2 molecule and larger N2 or CH4 molecules. Moreover, in order to be closer to the real applications, the defective Zr-fum-fcu- MOF nanoparticles based mixed-matrix membranes are constructed for natural gas purification under practical conditions

Biologics such as DNA and protein have immense biomedical applications, especially in diagnosis and therapy. However, many barriers hinder these applications, including biologics transport and liability in biological systems. Therefore, biocompatible and stable nanocarriers with high Biologics loading efficiency can provide a platform for advances in biologics applications. Metal-organic frameworks (MOFs) have gained significant interest within the biomedical field, mainly because of their building block versatility, porosity, stability, and chemical and biological functionality. Currently, increasing research is dedicated to improving MOFs biocompatibility, stability, and functionality for drug delivery. Using biomolecules as organic linkers could improve biocompatibility, physiological condition stability, and biological functionality. The main goal of this dissertation is to investigate the applicability of biomolecule-based Metal-organic frameworks (BioMOFs) as nanocarriers to achieve cellular delivery of active biologics. Herein, we analyzed adenine and saccharate metal−organic frameworks (BioMOF) in terms of biocompatibility, loading capability, protection, and cellular delivery of biologics. Our findings suggest that the usage of biomolecules as an organic linker generates BioMOFs with reduced cytotoxicity compared with the widely used MOFs such as Zinc Imidazole framework-8 (ZIF-8). In addition, the base-pairing functionality of coordinated adenine of KAUST-BioMOFs (KBMs) is preserved and can be used to load ssDNA. Both KAUST-BioMOFs (KBMs) and Zinc adenineated framework (ZAF) load, protect, and deliver functional ssDNA to cells. In addition, we showed the possibility of in situ encapsulation of active lysozyme in zinc saccharate (Zn-Sac) with modified synthesis procedures.

With the increasing demand for energy consumption and the limitations of traditional carbon-based energy sources, the importance of renewable energy generation is undeniable. Among the various methods for generating and storing energy, green hydrogen production through photocatalytic water splitting has gained significant interest. However, despite numerous studies dedicated to finding the perfect material, achieving large-scale industrial applications is still a distant goal. Metal-Organic Frameworks (MOFs) have emerged as a particularly intriguing option due to their exceptional tunability and versatility. Nevertheless, there remains a substantial gap in our understanding of their performance and fundamental aspects. In this study, we focus on Ti-based MOFs, which have shown great promise owing to the redox properties of titanium. We introduce a novel Ti-oxo chain pyrene MOF called ACM- 1, which exhibits remarkable activity in both the hydrogen evolution reaction (HER) and organic transformations. This outstanding performance can be attributed to the high mobility of photogenerated electrons and the strong localization of holes within the material. To further enhance the photocatalytic activity of ACM-1, we employ defect engineering techniques, specifically fluorination of the metal-oxo units. The introduction of fluorine effectively reduces the band gap of the material, leading to improved light absorption capabilities and a significant boost in photocatalytic performance. Additionally, we synthesize a new MOF named ICGM-1, which shares isochemical characteristics with the well-studied MIL-125-NH2. Despite the identical NH2-bdc linker, ICGM-1 differs in terms of its Ti-sbu composition, providing a unique opportunity to investigate the influence of node geometry on photocatalytic activity. Our study reveals that the rod-type geometry is unfavorable due to lower electron charge mobility, highlighting the importance of node architecture in designing efficient photocatalysts. Finally, we report the synthesis of two new Zr-based MOFs, ACM-10 and ACM-11, based on the redox-active TTFT linker. Through Ti grafting, we demonstrate the potential of ACM-10 for HER, further expanding the range of viable MOF photocatalysts.

No description available.

Metal organic frameworks (MOFs) are nanoporous materials composed of inorganic and organic structural building units (SBUs). Over the last several decades, interest in MOFs has grown considerably partially due to their promising capabilities for carbon capture and storage (CCS) technologies. This is mostly due to their tunable pore chemistry, high internal surface area and unique structural diversity. This thesis focuses on computational methods that were used to analyze and organize a database of hypothetical structures to facilitate MOF discovery. The work done is detailed in two main parts. In the first part of the thesis, a topologically diverse hypothetical MOF database, containing over 300,000 structures, is screened using simplified molecular-input line-entry system (SMILES) strings to identify SBUs in each structure. The structures in the database are then renamed according to the SBUs identified by the SMILES strings algorithm. The renaming of the structures allows users to have a good idea of the geometrical and topological distribution of the database. Furthermore, a quick and reliable test is developed to identify structures with incorrect bonding patterns/missing hydrogen. In the second part of the thesis, density functional theory (DFT) - derived charges are generated for each structure in the hypothetical MOF database. Using these charges, the CO₂/N₂ selectivity is calculated and compared with the selectivity values obtained from another charge generating method, split-charge equilibration (SQE), and it is determined that there is good agreement, r = 0.96, between the two methods. A machine learning model is then developed to identify relationships between geometrical features and CO₂/N₂ selectivity.

En los últimos años, los esfuerzos para desarrollar una fuente de energía limpia y econó³micamente viable se han incrementado. Estos esfuerzos surgen como respuesta al creciente consumo de combustibles y al alto impacto ambiental y socio-político de la exploración y el uso de hidrocarburos o energía nuclear. Una de las alternativas más prometedoras exploradas hoy en díaa es el uso de H2 como vector energético. Sin embargo, existen algunas limitaciones relacionadas con la producciónn y almacenamiento que deben ser superadas. Centrados en el problema del almacenamiento de H2 , en esta investigación se ha estudiado, empleando técnicas químico-computacionales, las propiedades físico-quí�micas que promueven la adsorción de hidrógeno en sólidos cristalinos microporosos metal-orgánicos (MOFs). A partir del análisis de los resultados, se han identificado algunos parámetros que pueden ser utilizados como referencia para orientar el diseño y la síntesis de nuevos MOFs con mejores propiedades para la adsorción de H2 . A lo largo del estudio, los siguientes aspectos han sido evaluadas en detalle: I. la naturaleza de las interacciones moleculares entre el adsorbato y los diferentes componentes del material y II. las características estructurales que promueven o limitar la adsorción. Estos aspectos fueron estudiados con técnicas de químico-computacionales, tales como cálculos de química cuántica (con métodos los semi-empíricos PM6, HF y MP2) y simulaciones de dinámica molecular y Monte Carlo. Los resultados se analizaron en una función de las propiedades fÃ�sicas de los ma- teriales seleccionados para el estudio. En una primera fase, la interacción de las moléculas de H2 con el MOF-5 se evaluaron a través de cálculos de química cuántica. En vista de que los sitios de adsorciónn más fuertes fueron localizados en posiciones cercanas a los Átomos del metal (Zn (II)), se realiza un estudio adicional con cuatro tipos de centros metálicos...... / Gómez Hernández, DA. (2012). Caracterización de la Adsorción de Hidrógeno en MOFs por Métodos Químico-Computacionales [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/17462