Chemistry Commons^™

Electrodeless Electrochemistry Enabled By Nonthermal Plasma, Harold Oldham

McKelvey School of Engineering Theses & Dissertations

The increasing availability and decreasing cost of electricity generated by renewable resources have motivated research into electrified chemical processing, whereby electrical energy is used to drive chemical transformations. Electricity-intensive processing techniques such as electrochemistry using solid electrodes has attracted attention in this context for the synthesis of organic compounds, such as high-value pharmaceuticals and renewable chemical production. Selective chemical transformations are achieved in conventional aqueous electrochemical systems by using external circuitry to bias solid electrodes, allowing for the preferential transfer of electrons between the electrode-liquid interface. Despite having the ability to promote controlled electrochemical reactions, configurations using solid electrodes are …

Electrochemical Studies Of Organic And Organometallic Compounds In The Pursuit Of Electrocatalytic Carbon Dioxide Reduction, Joshua J. Ludtke

College of Science and Health Theses and Dissertations

Carbon dioxide is the main contributor to the greenhouse effect in the world today; developing renewable energy sources and addressing anthropogenic CO₂ release into the atmosphere are two key ways of addressing its increasing impact. Electrocatalytic reduction to products like methanol or carbon monoxide is one useful path to address the rapid increase of carbon dioxide, and the fac-M(bpy-R)(CO)₃X family of complexes (M = Mn or Re; bpy-R = substituted 2,2’-bipyridine; X = Cl, Br, etc.) is one class of effective CO₂ reduction catalysts. Although the capability of the rhenium complex Re(PyBimH)(CO)₃Cl (PyBimH …

Electrochemical Studies Of Poly 3-(4-Methoxyphenyl)[5] Ferrocenophane-1,5-Dimethylene And Copolymers With Styrene And N-Phenylmaleimide, Niyati Arora

Electronic Theses & Dissertations

Ferrocene is an organometallic compound in which an iron atom is sandwiched between two cyclopentadienyl rings. Ferrocene containing polymers receive a considerable amount of research because of their known chemistry, stable redox reactions and useful electrical systems. Noteworthy are their uses as electrode coatings, electro-catalysts and as an anode in battery applications. In this research, the synthesis and polymerization of a ferrocenophane diene is reported. Using a Wittig reaction 3-(4-methoxyphenyl)[5]ferrocenophane-1,5-dimethylene was synthesized from 3-(4-methoxyphenyl)[5]ferrocenophane-1,5-dione. The homopolymer and copolymers with styrene and N-phenylmaleimide were synthesized via free radical polymerization from 3-(4-methoxyphenyl)[5]ferrocenophane-1,5-dimethylene using AIBN as the initiator. These polymers were characterized using …

Analysis And Differentiation Of Uniform And Localized Corrosion Of Cu, Roshan J. Daljeet

Electronic Thesis and Dissertation Repository

The current plan for disposal of used nuclear fuel in Canada involves sealing the waste in steel containers coated with 3 mm of copper and burying them in a deep geologic repository (DGR). The purpose of the copper coating is to provide corrosion resistance. To achieve long term containment, it is necessary that the copper layer corrodes slowly and predictably via active dissolution rather than passivating due to film formation. Film formation could allow pitting corrosion to occur in early phase repository conditions when groundwater ions such as Cl– , SO4 2– and HCO3 – play a dominant role in …

The Emerging Applications Of Sulfur (Vi) Fluorides In Catalysis, Nicholas Ball, Cayo Lee, Jonathan E. Elisabeth, Nathan C. Friede, Glenn M. Sammis

Pomona Faculty Publications and Research

The past decade has witnessed remarkable growth of catalytic transformations in organic sulfur(VI) fluoride chemistry. This Perspective concentrates exclusively on foundational examples that utilize catalytic strategies to synthesize and react S(VI) fluorides. Key mechanistic studies that aim to provide insight toward future catalytic systems are emphasized.

Exploring The Mechanism Of The Electrostatic Denaturation Of Double-Stranded Dna, Gayatri Raghu

Master's Theses

Electrostatic melting is an electrochemical tool that can be used to analyze the stability of DNA, allowing for the detection of various mutations in double-stranded DNA (dsDNA). Here, we explore the influence of electrostatic double layer formation on the unzipping of dsDNA to better comprehend the mechanism of this process. Previous studies by our lab show that the melting curve produced can distinguish between fully complementary 34-bp strands and a version of the same sequence in which one base pair has been replaced with a mismatch pair or detect and characterize the crosslinking of the dsDNA by anticancer drug cisplatin. …

Renewable Energy Conversion: Organic Redox Flow Batteries And Electrocatalytic Carbon Dioxide Reduction, Camden R. Debruler

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Steadily increasing global energy demands have pushed the industry to investigate renewable energy sources like solar and wind to help alleviate the strain on fossil fuel based non-renewable energy sources while also reducing carbon emissions. However, the energy producing power of these renewable technologies is limited by factors such as weather and the day-night cycle. Additional energy storage technologies are needed which are capable of storing excess energy during periods of high productivity, and delivering it when production rates fluctuate.

Batteries represent one possible energy storage device to meet this need. Specifically, redox flow batteries (RFBs) offer advantages in terms …

Electrochemical Oxidation Of Individual Silver Nanoparticles: Exploring The Effect Of Particle Shape, Capping Ligand, Electrolyte, And Potential On The Signal, Jazlynn Sikes

Graduate Theses and Dissertations

Nanomaterials have revolutionized science and technology. Their unique properties can be exploited, and nanoparticles are being used as catalysts, antimicrobials, drug delivery vehicles, sensors, and more. However, the fundamental properties of nanomaterials and their interactions with their surrounding environments are still poorly understood. In this work, a single-particle approach was used to observe the effects of capping ligand, surrounding solution, and particle shape on the oxidative process to gain deeper understanding of silver nanoparticle properties. When allowed the opportunity, the particles will adsorb to the electrode surface then oxidize in rapid succession upon electrode activation, regardless of capping ligand as …

Synthesis And Conductivity Analysis Of A Methyl (Polyethylene Glycol) Comb Polymer, Olivia Fox

Honors Theses

The overall goal of work in this field is to improve materials for use in a variety of applications in fuel cell and battery production. This thesis specifically investigates the synthesis of two variations of a methyl (polyethylene glycol) comb polymer electrolyte (MePEG_nwhere n=7) to understand how the molecular structure of an ion-conducting polymer affects its electrochemical properties. The MePEG used in this synthesis contains seven ethylene glycol groups and was added to a poly (methylhydrosiloxane) comb polymer backbone. In the first sample, the polymer contained only the MePEG sidechain, and in the second sample, the polymer contained …

Alternative View Of Oxygen Reduction On Porous Carbon Electrocatalysts: The Substance Of Complex Oxygen-Surface Interactions, Giacomo De Falco, Marc Florent, Jacek Jagiello, Yongqiang Cheng, Luke L. Daemen, Anibal J. Ramirez-Cuesta, Teresa J. Bandosz

Publications and Research

Electrochemical oxygen reduction reaction (ORR) is an important energy-related process requiring alternative catalysts to expensive platinum-based ones. Although recently some advancements in carbon catalysts have been reported, there is still a lack of understanding which surface features might enhance their efficiency for ORR. Through a detailed study of oxygen adsorption on carbon molecular sieves and using inelastic neutron scattering, we demonstrated here that the extent of oxygen adsorption/interactions with surface is an important parameter affecting ORR. It was found that both the strength of O2 physical adsorption in small pores and its specific interactions with surface ether functionalities in the …

Investigating The Corrosion Behaviour Of Ni-Based Alloys In Industrially Relevant Environments, Jeffrey D. Henderson

Electronic Thesis and Dissertation Repository

Typical engineering materials may experience high corrosion rates when exposed to aggressive service conditions. Such conditions include high concentrations of aggressive anions and oxidants, high solution acidity, and/or high temperatures. Alloys with high corrosion resistance may be selected to avoid material failure caused by corrosion, for example, Ni-Cr-Mo alloys. These alloys exhibit excellent corrosion resistance due to the formation of a passive oxide film, primarily containing Cr and Mo. However, film breakdown can result in localized corrosion, e.g., crevice corrosion. Localized corrosion processes can penetrate deep into the bulk alloy, threatening its integrity. While the oxide film and localized …

Developing Methods For Diversifying Molecular Scaffolds Directly On A Microelectrode Array, Nai-Hua Yeh

Arts & Sciences Electronic Theses and Dissertations

Microelectrode arrays contain collections of spatially isolated electrodes that can be individually addressed. Thus, the arrays have the potential to support synthesis of molecular libraries if unique members of the library can be located next to unique electrodes in the array. The result would be an intriguing platform for screening the molecules in the library against biological receptors in order to identify high-affinity ligands for those targets, especially since the arrays themselves can be directly used in the signaling studies. To expand the capabilities of the arrays, the goal of this thesis is to develop the new array chemistry needed …

Enhanced Electrochemical And Light-Driven Co2 Reduction By Incoporating Pendant Functionality In The Second-Coordination Sphere Of Molecular Catalysts, Sayontani Sinha Roy

Electronic Theses and Dissertations

With the increase in global population and rapid industrialization, a gigantic amount of greenhouse gases is being released into the atmosphere each year. The catastrophic effect of these accumulated greenhouse gases is driving global climate change and adversely impacting our ecosystem. Popularizing the traditional renewable energy sources (such as solar and wind energy) can mitigate the problem by cutting down anthropogenic CO2 emissions, which is the major contributor to this global problem. However, the intermittent nature of these energy sources is problematic to reliably power society throughout the year. Therefore, converting CO2 to various value-added chemicals with the aid of …

Synthesis Of Nonperipherally Tetra-[5-(Diethylamino)-2-Formylphenoxy] Substituted Metallophthalocyanines And Their Electrochemistry, Turgut Keleş, Di̇lek Ünlüer, Zekeri̇ya Biyiklioğlu, Yasemi̇n Ünver

Turkish Journal of Chemistry

3-[5-(diethylamino)-2-formylphenoxy]phthalonitrile (n-TY-CN), metallophthalocyanines n-TY-Co, n-TY-Cu, and n-TY-Mn bearing [5-(diethylamino)-2-formylphenoxy] groups at nonperipheral positions were prepared for the first time. These compounds were characterized with IR, NMR (only for n-TY-CN), mass and UV-vis (except n-TY-CN) spectroscopy. Voltammetric characterizations of n-TY-Co, n-TY-Cu, and n-TY-Mn revealed that while n-TY-Co, n-TY-Cu, and n-TY-Mn showed characteristic Pc ring and/or metal-based reduction reaction, n-TY-Co, n-TY-Cu, and n-TY-Mn were coated on the working electrode during the oxidation processes owing to the cationic electropolymerizations of the [5-(diethylamino)-2-formylphenoxy] substituents.