We report the use of MIL-120 as a water-stable and cost-effective metal-organic framework (MOF) for selectively capturing CO₂ from wet flue gas. Synthesized using inexpensive and environmentally benign reagents in water, MIL-120 possesses one-dimensional pores decorated with hydroxyl-bridged Al(III) ions and benzene rings with an interstitial spacing of 4.78 Å....
In this report, two studies are presented that utilize computations to predict and elucidate the reaction mechanisms of two different copper catalyzed reactions. Each study provides insight into the various chemical transformations, as well as the how and why behind regioselectivity and isotopic selectivity. The importance of this research is...
Metal-oxo clusters are discrete molecular metal-oxides. Most metals form numerous cluster compounds that can be ligated, unligated, charged or neutral, controlling their solubility in water and/or organic solvents. They are important species to study reaction pathways from the monomeric building units to the bulk metal oxides, and have many application...
This work investigates the effect of cation substitution on the properties of the lead-free, solid solution (Na₀.₅Bi₀.₅)TiO₃-BaTiO₃ (NBT-BT). Substitution into NBT-BT increases disorder and increases the relaxor ferroelectric properties. These relaxor ferroelectric materials show large piezoelectric strains that can be utilized in actuator applications. Ceramic samples were prepared using standard...
In this dissertation, excited state proton transfer (ESPT) and its inhibition in solution and protein environments are revealed using both femtosecond transient absorption (fs-TA) spectroscopy and femtosecond stimulated Raman spectroscopy (FSRS). Using a tunable Raman pump to enhance transient vibrational features of the photoacidic chromophore HPTS in methanol and methanol...
Aqueous hydroxo Hf nanoclusters enable studies to identify and codify steps in the deposition of Hf-based oxide thin films from solution precursors. HfOCl2 reacts with combinations of H2O2(aq), acids, and TMAH to produce polymetal species at high pH and low pH. X-ray scattering and spectroscopic methods reveal the nature of...
Phosphate and peroxide stabilize new oxo-hydroxo niobium clusters in water at low pH. The clusters open a new chapter in aqueous niobium chemistry under acidic conditions. The clusters also produce atomically smooth, amorphous niobium oxide phosphate (NbPOx) thin films. Reaction pathways from cluster solutions to amorphous niobium oxide phosphate solids...
In this dissertation, the spectroscopic properties and thermodynamic stability of a class of materials known as metal oxo and hydroxo clusters are studied. In aqueous solutions, many metals can aggregate into discrete clusters of metals bridged by oxo or hydroxo ligands. These clusters are of particular interest to us for...
Polyoxometalates are a rapidly growing class of discrete metal oxide clusters with a wide range of applications including functional materials. These anionic clusters of the group V and VI transition metals are inexpensive and non-toxic. Within group V polyoxometalates, niobium and tantalum chemistry has been underdeveloped owing to their unique...
The subject of this PhD thesis is part of a research domain of great present interest in new semiconductor materials for photovoltaic and thermoelectric applications. This domain contains the elaboration and the study of both Cu-based chalcogenides bulk and thin-film samples, driven by materials design principles.
One of the most...