Two approaches to the tricyclic core of the furanoeremophilane sesquiterpenoids are described. The first approach entails a projected Diels-Alder/retro Diels-Alder reaction of an acetylenic oxazole 64. Construction of the pivotal aldehyde 67 commenced from ketone 68. The acetyenic moiety was then introduced via a Felkin-Ahn addition of lithiopropyne to aldehyde...
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...
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...
The variegated aqueous chemistries of metal cations are applied to the design and synthesis of non-toxic solution precursors suitable for additive printing of large-area oxide electronics. Polycondensation behaviors of aqueous Al+3 and PO4 +3 are manipulated in the deposition of atomically smooth amorphous aluminum oxide phosphate (AlPO) dielectric films. AlPO...
Chemistry of preparing dense film from solution deposition is explored with several cases in this thesis. Surface dense structure, conversion at melting point, and ion exchange in aqueous solution are the main topics covered here for the thin films of aluminum oxide phosphate and tin dioxide. Thin film density, optical...
This work investigates the relationship between the local structure and physical properties of a set of classical (MgTiO3, CaTiO3, SrTiO3, and BaTiO3) and complex ((1-x)Ba(Zr0.2Ti0.8)O3-x(Ba0.7Ca0.3)TiO3[BZT-BCT], Na0.5Bi0.5TiO3 [NBT]) perovskite electroceramics. The materials in this work were synthesized via standard solid state ceramic synthesis, the structure was investigated through a number of...
Novel graphite intercalation compounds (GICs) and associated chemistry have been explored, specifically: (1) containing alkyl- substituted imidazolium cations; (2) a series containing alkaline earth metal (Mg, Ca, Sr, Ba) cations with ethylenediamine (en) co-intercalates; (3) showing reversible intragallery M-M bonding and (4) via electrochemical intercalation of Mg cations with potential...
In this dissertation, the process of computational modeling of amorphous oxide materials is studied. Amorphous oxides have random atomic arrangements with no long-range structural order which makes it difficult to study structure-property relationships. Despite the difficulties, amorphous oxides have great uses as semiconductors and dielectrics in thin-film transistors. The ability...
Novel synthetic strategies are developed to prepare new intercalation compounds and nanocomposites with several layered hosts (NiPS₃, Na-montmorillonite, MoS₂ and MoO₃). In these products, alkali metals are ionic intercalates and linear polymers, dendrimers or amines act as co-intercalates. In addition to new synthetic approaches, new structures are identified and characterized....
The materials Fe₂(Si,Ge)(S,Se)₄, Cu₃PS[subscript 4-x]Se[subscript x] (0 ≤ x ≤ 4), and Cu₃PxAs[subscript 1-x]S₄ (0 ≤ x ≤ 1) have been synthesized and studied as new earth-abundant absorbers for single and multijunction photovoltaic cells as well as solar fuel generation. The synthesis, single-crystal growth, and optical and electrical properties of...