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dc.contributor.advisorTrewyn, Brian
dc.contributor.advisorGennett, Thomas
dc.contributor.authorRussell-Parks, Glory Alwyn
dc.date.accessioned2024-07-10T19:15:39Z
dc.date.available2024-07-10T19:15:39Z
dc.date.issued2023
dc.identifierRussellParks_mines_0052E_12775.pdf
dc.identifierT 9693
dc.identifier.urihttps://hdl.handle.net/11124/179128
dc.descriptionIncludes bibliographical references.
dc.description2023 Fall.
dc.description.abstractPorous materials have demonstrated to be profoundly applicable for decades. There are several classes of porous materials which are defined by their pore size: microporous (< 2 nm), mesoporous (2-50 nm), and macroporous (> 50 nm). Each have specific areas where their utility dominates. While all classes of porous materials are heavily studied and used, mesoporous materials demonstrate incredible versatility and applicability. The ability to tune the surface area, pore size, morphology, etc., make mesoporous materials highly functional for applications in catalysis and water purification. The properties mentioned above can be adjusted through relatively small changes in synthetic methods. Different mesoshapes, pore arrangements, and pore volumes can be achieved by incorporating different surfactants and adjusting the duration and temperature at which hydrolysis and condensation occur. Considering the variety of mesoporous materials, mesoporous metal oxides and mesoporous silica nanomaterials (MSN) are heavily investigated for various applications. Direct air capture (DAC) is currently a method at the forefront for capturing dilute concentrations of CO2 from the atmosphere. Composite porous materials consisting of chemisorbent amines such as polyethyleneimine supported in solid mesoporous oxides like γ- A2O3 are the state-of-the-art sorbent for DAC technology. In this work, a fluorescent probe was incorporated into the sorbent to elucidate the effects of moisture on polymer mobility and CO2 adsorption using photoluminescence spectroscopy in the above mentioned composite systems. A well-controlled, systematic method was developed to examine sorbent behavior in various environments. Polymer mobility was better retained in the presence of moisture allowing greater CO2 uptake. This work demonstrated the development of novel characterization techniques to qualitatively assess material behavior under various conditions. With the current transition away from carbon-based fossil fuels, hydrogen has received a lot of attention to serve as a potential new source of energy. One of the main challenges and motivations for hydrogen research is the low volumetric energy density of molecular hydrogen. The technology and methodology behind liquid organic hydrogen carriers (LOHC) is one solution to this problem. Although LOHC technology has been commercialized, improvements are needed in the process for both hydrogenation, and dehydrogenation for increased global usage. Frustrated Lewis pairs (FLPs) and light-responsive catalysts were examined and synthesized as alternatives to the current state-of-the-art catalysts. Given the activity and synthetic flexibility of FLPs, if successful, their use in this area could reduce the quantity of precious metals used by this industry. After unsuccessful synthetic attempts of a novel FLP catalyst, a commercially available FLP was examined for its ability to hydrogenate benzyl toluene. The commercial FLP was found to be partially successful, indicating these catalysts may be viable for further applications. A secondary area of research focused on reducing the energy (heat) requirement of (de)hydrogenation of LOHCs through the use of the designed-light responsive catalysts. We designed, synthesized, and examined these mesoporous silica based catalysts for the dehydrogenation of formic acid. The results showed preliminary success and provided valuable insight and information regarding these photo-catalysts and their activity. Atrazine is a commonly used herbicide which has shown to be toxic to some species. Triazine hydrolase (TrzN) can catalyze the irreversible dechlorination of atrazine to its non-toxic hydrogenated derivative. There are, however, separation and recovery issues that arise with the use of TrzN for water remediation. Fortunately, there are numerous examples of synthesized biomaterials that utilize MSN to protect enzymes from non-native conditions. Various biocatalysts were synthesized and analyzed for atrazine degradation, and it was determined that a medium pore sized MSN with a chitosan coating demonstrated the highest (retained) activity when exposed to non-native conditions (co-solvent, pH, high temperature). This materials activity was also preliminarily examined in water samples from Clear Creek to ensure the biocatalyst retained its activity when exposed to components found in natural water sources. While the motivation, research, and goals of these projects are individually quite different, the commonality is the utilization of mesoporous materials to investigate various properties related to the given application. This collection of work further demonstrates the diverse applicability of this class of materials. As mesoporous materials continue to be used and uniquely designed for a given application, structure-function relationships will become better understood which will influence and encourage the use of these materials in industries.
dc.format.mediumborn digital
dc.format.mediumdoctoral dissertations
dc.languageEnglish
dc.language.isoeng
dc.publisherColorado School of Mines. Arthur Lakes Library
dc.relation.ispartof2023 - Mines Theses & Dissertations
dc.rightsCopyright of the original work is retained by the author.
dc.titleTuning mesoporous materials for various applications
dc.typeText
dc.date.updated2024-06-25T01:21:12Z
dc.contributor.committeememberPylypenko, Svitlana
dc.contributor.committeememberVyas, Shubham
dc.contributor.committeememberWolden, Colin Andrew
thesis.degree.nameDoctor of Philosophy (Ph.D.)
thesis.degree.levelDoctoral
thesis.degree.disciplineChemistry
thesis.degree.grantorColorado School of Mines


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