Inorganic Chemistry Commons^™

Research And Development Of Optically Transparent Join With Low Processing Temperatures, Eric Kevin Muskovin

Masters Theses

The purpose of this study was to investigate durable solar cell cover glass joins produced by diffusion bonding with deep eutectic solvents (DES) and to develop a novel process of joining optically transparent materials at low temperatures. A joined PV cell-glass specimen was characterized using Raman, μ-FTIR, SEM-EDS, and thin-film XRD. DESs were created with malonic acid (MAL) and choline chloride (ChCl) of varying composition factors (CF; CF=MAL/ChCl). Joining borosilicate glass coupons was attempted using DESs with CF = 0.65 and 1 at temperatures between 100-150 °C for 20 hours. Joining the glass coupons failed at all temperatures and oxygen …

Stability Of Bimetallic Clusters In Protein Model Systems, Sean Hartnett

Master’s Theses

Heterobimetallic cofactors are commonly found in proteins and allow them to perform unique chemical processes that would otherwise not be possible. The interactions between these metals allow the protein to accomplish difficult chemical transformations. Previously, the thermodynamic stability of a Fe^II /Mn^II cluster in the dinucleating ligand F-HXTA (5-fluoro-2-hydroxy-1,3-xylene-α,α′-diamine-N,N,N′,N′-tetraacetic acid) has been investigated in our lab as a model of cluster assembly in the proteins ribonucleotide reductase (RNR) and R2-like ligand binding oxidases (R2lox). By measuring equilibrium concentrations of F-HXTA complexes via ¹⁹F-NMR, it was found that the equilibrium for metal exchange between the homobimetallic …

Synthesis Of New Bodipy Analogs, John Dilyard

Williams Honors College, Honors Research Projects

This report examines the synthesis of new ligands based upon dipyrazolylmethane and diindazolylmethane. The goal of these modifications is to increase the acidity of the proton on the methyl carbon to allow for deprotonation. The ligands synthesized were dipyrazolylphenylmethane and diindazolylphenylmethane, as well as modifications of the latter. The products were analyzed by NMR spectroscopy and one crystal structure was obtained of diindazolylphenylmethane.

Colloidal Synthesis And Photophysical Characterization Of Group Iv Alloy And Group Iv-V Semiconductors: Ge1-Xsnx And Sn-P Quantum Dots, Venkatesham Tallapally

Theses and Dissertations

Nanomaterials, typically less than 100 nm size in any direction have gained noteworthy interest from scientific community owing to their significantly different and often improved physical properties compared to their bulk counterparts. Semiconductor nanoparticles (NPs) are of great interest to study their tunable optical properties, primarily as a function of size and shape. Accordingly, there has been a lot of attention paid to synthesize discrete semiconducting nanoparticles, of where Group III-V and II-VI materials have been studied extensively. In contrast, Group IV and Group IV-V based nanocrystals as earth abundant and less-non-toxic semiconductors have not been studied thoroughly. From the …

Investigation Of Gold(Iii) Complexes With Hiv-Ncp7 And Models, James Beaton

Theses and Dissertations

The medicinal uses of gold date as far back as 2500 B.C. in China. In modern times, gold has been used in the treatment of a number of different human diseases including rheumatoid arthritis, cancer, and viral infections. This dissertation will focus on the development of gold complexes for the purpose of selective inhibition of HIV NCp7, a 55 amino acid zinc finger protein with two Cys₃His zinc binding domains.

NCp7 is involved in a number of viral life cycle processes including activation of reverse transcription, integration, DNA recognition, RNA packaging, and formation of the viral envelope. The …

Nickel-Catalyzed Oxidative Decarboxylative (Hetero)Arylation Reactions, Aaron P. Honeycutt

Graduate Theses, Dissertations, and Problem Reports (ETD)

Transition-metal-catalyzed decarboxylative coupling reactions have gained considerable attention over the past decade as an efficient route to form heterobiaryls. However, current methods for oxidative decarboxylative (hetero)arylation with unactivated C-H bonds have been limited by poor substrate scope, control of regioselectivity, and chemospecificity. This thesis describes the development of a new nickel-catalyzed oxidative decarboxylative coupling (ODC) with unactivated C-H bonds. The first chapter discusses the development of the new nickel-catalyzed ODC reaction to enable the coupling of a N,N'-bidentate directing group with a broad scope of heteroaromatic carboxylates and ortho-substituted benzoates, a scope that has not been achieved in previous …

New Approaches To Cyclopentadienyl-Fused Thiophene Complexes Of Iron And Synthesis And Characterization Of Carbonic Anhydrase Active-Site Mimics For Co2 Hydration, Deepshikha Gupta

Theses and Dissertations--Chemistry

Polyheterocycles such as polythiophene and its derivatives comprise an important class of conducting polymers used for electronic applications. They have been of great interest for use in electronic materials due to their increased environmental stability as well as novel electronic properties in their polymer states. We have been interested in exploring the electronic properties of organometallic analogues of the low-band-gap polymer poly(benzo[3,4-c]thiophene) (polyisothianaphthene) that incorporates η⁵-cyclopenta[c]thienyl monomers such as ferroceno[c]thiophene. First chapter of this dissertation involved synthetic attempts to ferroceno[c]thiophene. Exploring a shorter synthetic route to starting material, 1,2-di(hydroxymethyl)ferrocene was …

Catalytic Conversion Of Monosaccharides Into 5-(Hydroxymethyl)Furfural In Ionic Liquids Using Aluminum Complexes Bearing Bidentate (Aminomethyl)Phenolate Ligands, Daudi Sayialel Saang'onyo

Theses and Dissertations--Chemistry

Currently, the major sources of fuel, energy, and chemicals are nonrenewable fossil resources such as petroleum, natural gas, and coal. Additionally, petroleum is used for the production of most transportation fuels and for the production of about 95% of organic chemicals. However, the production and use of non-renewable fossil fuels are unsustainable. For economic and environmental sustainability, there is a need to search for new and/or renewable resources and technologies for energy, fuels, and chemicals production that have the potential of effectively substituting fossil resources. In this context, lignocellulosic biomass is one of the candidates that meet these requirements due …

Heterogeneous Catalytic Deoxygenation Of Lipids To Fuel-Like Hydrocarbons Over Improved Bimetallic Nickel Catalysts, Ryan Andrew Loe

Theses and Dissertations--Chemistry

Diminishing petroleum reserves and environmental considerations have strengthened the demand for developing renewable fuel technologies. One alternative is deoxygenating plant oils, animal fats, and waste lipid streams to fuel-like hydrocarbons. These fuels offer a drop-in replacement to petroleum products while potentially becoming carbon neutral, satisfying both fuel and environmental concerns. This fuel is obtained through catalytic deoxygenation via either hydrodeoxygenation (HDO) or decarboxylation/ decarbonylation (deCO_x). HDO requires problematic sulfided catalysts and extreme hydrogen pressures to convert lipids to fuel-like hydrocarbons. Therefore, this work focuses on the deCO_x pathway, where hydrogen is not required for deoxygenation to take …

Synthesis And Characterization Of A Novel Platinum Ligand Complex ((Κ-N,C,N- 2,6-Bis(Diethylaminomethyl)Phenyl)(4- Tert-Butylphenyl) Platinum(Ii)), Carly Roleder

CMC Senior Theses

A novel platinum ligand complex (NCN)PtAr, ((κ-N,C,N- 2,6-bis (diethylaminomethyl)phenyl)(4- tert-butylphenyl) platinum(II)), was synthesized. A reaction of 1-Bromo-4-tert-butylbenzene Grignard with (NCN)PtCl, (where NCN = 2,6-bis(diethylaminomethyl)phenyl) yielded the (NCN)PtAr (where Ar = 4-tert­-butylphenyl). The product was then characterized with NMR spectra through ¹H NMR, ¹³C NMR, COSY, HSQC, and HMBC to verify it structure.

Bimetallic Complexes: The Fundamental Aspects Of Metal-Metal Interactions, Ligand Sterics And Application, Michael Bernard Pastor

University of the Pacific Theses and Dissertations

Metal containing complexes have been used to catalyze various organic transformations for the past few decades. The success of several mononuclear catalysts led to transition metal catalysts used in pharmaceuticals, environmental, and industrial processes. While mononuclear complexes have been used extensively, bimetallic systems have received far less attention. Bimetallic or polynuclear sites are commonly found in metalloenzymes that perform elegant transformation in biological systems, underlying their significance. Inorganic chemists take inspiration from nature and design model bimetallic complexes to further study this cooperativity effect. A bimetallic platform offers many structural and functional differences such as the identity of the metal …

Principles Of Surface Chemistry Central To The Reactivity Of Organic Semiconductor Materials, Gregory J. Deye

Dissertations

Organic thin-films are rapidly becoming implemented as semiconducting materials in electronic devices and as a result, surface reactivity plays an increasingly important role in the improvement of semiconducting properties. My dissertation addresses how organic thin-films react with gaseous molecules. Previous reports of chemical reactions on organic surfaces claim, “phase rebuilding reaction mechanisms,” whereby reactions only proceed if chemisorbed adsorbate molecules are able to traverse through voids in the molecular lattice. The over-assumptions of this model and lack of correlation to reaction temperature make understanding of organic substrate reactivity incomplete. In contrast, I argue applied heat causes deformation of the molecular …

Surface Modification For The Improvement Of Metal/Organic Semiconductor Interfaces, Jonathan Paul Hopwood

Dissertations

Organic electronics have become much of the forefront of scientific research due to their advantages over tradition electronics as well as their applications in consumer devices, medical devices, and harnessing renewable sources of energy. Despite their appeal, two major obstacles are responsible for poor performance and limited applications. These problems occur at the interface between the two main components of the devices, the organic semiconductor and the metal electrodes. The first, high electrical resistance, is a result of the misalignment between the metal’s free electrons and the organic semiconductor’s conduction band. We seek to capitalize on this misalignment using light-responsive …

Fabrication And Characterization Of Intricate Nanostructures, Treva T. Brown

LSU New Orleans Theses and Dissertations

Encapsulation of nanoparticles within hexaniobate nanoscrolls presents interesting advances in the formation of nanocomposites exhibiting unique multi-dimensional properties. Building upon previous successes, facile yet versatile wet-chemical and microwave-irradiation synthetic protocols for the fabrication of a series of hexaniobate composites are presented herein. Solvothermal and, more recently, microwave-assisted methods have been developed that allow for the fabrication of peapod-like structures. During solvothermal treatment, exfoliated hexaniobate nanosheets scroll around highly ordered chains of preformed nanoparticles (NPs) to produce nanopeapods (NPPs). This approach offers versatility and high yields, in addition to the potential for advanced functional device fabrication.

For the characterization of these …

Synthesis, Characterization, And Spectroscopy Of Donor-Acceptor Charge Transfer Complexes, Dominic Kofi Kersi

Chemistry and Chemical Biology ETDs

A series of square-planar metal (diimine)(dichalcogenolene) chromophoric complexes have been synthesized, characterized and studied spectroscopically. Studies conducted on diimineplatinum(II) dichalcogenolene complexes (LPtL’) using time resolved spectroscopic techniques such as transient absorption and emission, reveal a charge-separated excited state of the type dichalcogenolene → diimine charge-transfer (LL’CT) [(dichalcogenolene^•+)Pt(diimine^•-) with an open shell donor-acceptor biradical character. This makes the low-energy ligand-to-ligand charge-transfer (LL’CT), or the mixed-metal ligand-to-ligand charge-transfer (MMLL’CT), transitions of diimineplatinum(II) dichalcogenolene complexes particularly interesting to us in facilitating our knowledge of biradical charge-separated states. Long-live excited state lifetimes were observed for these complexes upon visible photoexcitation …

Layer-By-Layer Assembled Membranes With Immobilized Porins, Sebastián Hernández, Cassandra Porter, Xinyi Zhang, Yinan Wei, Dibakar Bhattacharyya

Chemical and Materials Engineering Faculty Publications

New and advanced opportunities are arising for the synthesis and functionalization of membranes with selective separation, reactivity, and stimuli-responsive behavior. One such advancement is the integration of bio-based channels in membrane technologies. By a layer-by-layer (LbL) assembly of polyelectrolytes, outer membrane protein F trimers (OmpF) or “porins” from Escherichia coli with central pores ∼2 nm in diameter at their opening and ∼0.7 × 1.1 nm at their constricted region are immobilized within the pores of poly(vinylidene fluoride) microfiltration membranes, in contrast to traditional ruptured lipid bilayer or vesicle processes. These OmpF-membranes demonstrate selective rejection of non-charged organics over ionic solutes, …

Evaluating Ligand Assisted Activation Of Small Molecules Through Proton Reduction And Alcohol Oxidation., Rahul Jain

Electronic Theses and Dissertations

Hydrogen is a potential alternate to the carbon fuels to meet the future demands for energy in an eco-friendly manner. Hydrogen produced by the electrolysis of water is stored in fuel cells which on demand can be converted into electrical energy upon the reaction with oxygen. In the quest for economically viable electrocatalysts for hydrogen evolution, the work in this dissertation describes evaluation of nickel based catalysts coordinated to redox active ligands, dialkyl/diarylphosphine benzenethiol and bis(thiosemicarbazone) for their ability to generate hydrogen with external acids as a proton source. A nickel complex with the benzenethiol ligand framework follows a traditional …

The Electrochemical Deposition Of Samarium And Europium Dissolved In Ionic Liquid Solvent, Bea Martinez

UNLV Theses, Dissertations, Professional Papers, and Capstones

Rare-earth elements include the lanthanide series in the periodic table with the addition of scandium and yttrium. China produces approximately 95% of the world’s rare-earths supply and is the largest consumer of the world’s rare earth supply. Domestic production of rare-earth metals is a priority in the US. The domestic demand for rare-earth elements is largely based on their use in electronic devices, catalytic converters, and more importantly defense applications. Therefore, China’s monopoly of rare-earth elements is viewed as a threat to national security. Although capital investments have resulted in an increase in domestic mining and refining of rare-earth materials, …

Synthesis And Electrochemical Characterization Of Pani/Ni And Pani/Au/Ni Composites, Morgan Emily Pacini

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this research is to show that the electrochemically controlled formation of monometallic and bimetallic catalysts in polyaniline (PANI) can directly influence the efficiency and reproducibility of the catalytic oxidation of methanol. PANI is a conductive polymer that provides a three-dimensional template for the metallic catalysts deposition at nitrogen sites. The controlled deposition of metallic species can be achieved using the normal oxidation/reduction cycles of PANI. The deposition of metallic species relies on anion precursors that are electrostatically bound by the polymer during the oxidation cycle. The precursor is reduced directly at the nitrogen sites in the polymer …

Nano/Submicro-Structured Iron Cobalt Oxides Based Materials For Energy Storage Application, Hongyan Gao

Masters Theses & Specialist Projects

Supercapacitors, as promising energy storage devices, have been of interest for their long lifespan compared to secondary batteries, high capacitance and excellent reliability compared to conventional dielectric capacitors. Transition metal oxides can be applied as the electrode materials for pseudocapacitors and offer a much higher specific capacitance. Co3O4 is one of the most investigated transition metal oxides for supercapacitor. Besides simple monometallic oxides, bimetallic transition oxides have recently drawn growing attention in electrochemical energy storage. They present many unique properties such as achievable oxidation states, high electrical conductivities because of the coexistence of two different cations in a single crystal …