Date of Award
Spring 2023
Document Type
Dissertation
Degree Name
Doctor of Philosophy (PhD)
Department
Chemical and Environmental Engineering (ENAS)
First Advisor
Fortner, John
Abstract
Despite recent advancements in water treatment processes, contaminants of emerging concerns (CECs), such as perfluorinated compounds, endocrine disruptors, pharmaceuticals and personal care products, and pesticides, among others, remain a challenge for conventional treatment processes. To address this, tailored, fit−for−purpose water treatment strategies are needed to meet specific raw water quality and end−user needs. Recently, advancements in engineered materials and processes at the nanoscale hold promise towards improving (or even reimagining) related environmental technologies. Nanoscale engineering and materials have been demonstrated to enable unique properties/processes, including high reactivity, allowing for enhanced adsorption, degradation, and filtration – and thus have significant potential to improve conventional water treatment processes. To achieve this, material surface engineering (and related understanding) specifically for aqueous systems is crucial regarding both material performance and stability/durability.Research presented in this dissertation is focused on developing nanomaterials with rational surface design and engineering for advanced aqueous environmental applications with the goal of gaining fundamental understanding of emerging physical and chemical dynamics. Throughout the work, research is focused on two material aspects: (1) engineering and characterizing (in)organic surface coatings on/for metal oxide nanocrystals; and (2) surface−based (supported), novel (metal) nanocatalysts. Through these foci, we demonstrate the critical role of material surface chemistry and explore several material−based treatment applications. By engineering organic surface coating(s) on metal oxide(s) (e.g., superparamagnetic iron oxides) nanocrystals, ultra−high sorption capacity, for PFAS, (via, optimized organic coatings) is described. The potential of microwave enhanced catalytic degradation for organic compounds is demonstrated via inorganic surface coating(s). Surface design for precisely controlled, mono− and bi−metallic nanoscale (i.e., atomic cluster) catalysts on nanoscale mesoporous silica (platform) is also demonstrated which can be tuned for effective nitrate reduction with high reaction kinetics and product selectivity. Lastly, I present recent findings on surface modified (nanocomposite) metal organic framework (MOF) materials for enhanced photocatalytic PFAS degradation. Taken together, this work, spanning from rational material design to synthesis and characterization to bench−scale demonstration, allows for fundamental process insight and material optimization. As presented, new knowledge directly contributes the realization of surface functionalized nanomaterials for environmental applications and beyond.
Recommended Citation
Lee, Junseok, "Engineering Nanomaterials for Advanced, Aqueous−Based Applications: Exploring Physical and Chemical Dynamics with a Focus on Surface Chemistry" (2023). Yale Graduate School of Arts and Sciences Dissertations. 1472.
https://elischolar.library.yale.edu/gsas_dissertations/1472
