Engineering Commons^™

Enhanced Kinetics And Modeling Of Pan-Based Carbon Felt Anodes In Vanadium Redox Flow Batteries, Michael Cyrus Daugherty

Doctoral Dissertations

All-vanadium redox flow batteries (VRFBs) are a promising technology for grid-level energy storage, however, there are still several limitations in the forms of durability, efficiency, and overall costs, which are barriers to its commercial viability. With both bulk electrolyte flowing through its porous matrix and species flux at the solid-electrolyte interface, electrodes are the component of VRFB systems which host electrochemical reactions and facilitate contact between the liquid phase electrolyte and the electronically conductive solid phase. While the more limiting electrode in VRFB systems is dependent on the material, for polyacrylonitrile (PAN)-based carbon felts, the anode constitutes a larger portion …

Mxenes As Flow Electrodes For Capacitive Deionization Of Wastewater, Naqsh E. Mansoor

Boise State University Theses and Dissertations

The energy-water nexus poses an integrated research challenge, while opening up an opportunity space for the development of energy efficient technologies for water remediation. Capacitive Deionization (CDI) is an upcoming reclamation technology that uses a small applied voltage applied across electrodes to electrophoretically remove dissolved ionic impurities from wastewater streams. Similar to a supercapacitor, the ions are stored in the electric double layer of the electrodes. Reversing the polarity of applied voltage enables recovery of the removed ionic impurities, allowing for recycling and reuse. Simultaneous materials recovery and water reclamation makes CDI energy efficient and resource conservative, with potential to …

Brominated Carbon Materials As Positive Electrodes For Nonaqueous Secondary Lithium-Bromine Batteries, Benjamin Beau Peterson

LSU Doctoral Dissertations

Secondary lithium-bromine (Li-Br₂) batteries have theoretical potentials near 4.1 V vs Li/Li⁺ and capacities more than 2 times greater than conventional Li-ion batteries. Herein, secondary, non-aqueous Li-Br₂ half-cell batteries are reported using a Li metal anode, carbon-coated glass fiber separator, non-aqueous Li-based electrolytes with and without the addition of lithium bromine (LiBr) salt, and positive electrodes consisting of either chemically brominated non-graphitic carbon or carbon derived from the carbonization of metal-organic frameworks (MOFs) with LiBr embedded into the micro- and mesopores of the carbon matrix. The separator is effective in mitigating the transport of Br_{2 …}

Engineering Ionomer Materials For Addressing Ohmic Resistances In Electrochemical Desalination And Waste Heat Recovery, Varada Menon Palakkal

LSU Doctoral Dissertations

Water scarcity and energy availability present important challenges that need to be addressed in the coming centuries. In the front of water technologies, desalting brackish water is of extreme importance for thermal electric power plants, chemical manufacturing plants, and other industrial operations that treat and reuse their water utilities. Membrane capacitive deionization (MCDI) is an energy efficient desalination technique that has drawn attention from commercial entities. Most material research studies on MCDI focus on enhancing electrode performance while little emphasis is given to rationale design of ion-exchange membranes (IEMs). In this work, the ionic conductivity, permselectivity, and thickness for three …

Theoretical Investigation Of Fundamental Cathode Processes In Metal-02 Batteries, Saurin Hiren Rawal

LSU Doctoral Dissertations

In this thesis we theoretically explore the different fundamental phenomena associated with metal-air batteries (where the metal can be Li, Na or K) using first principles density functional theory. We start by investigating the adsorption of the starting reactants/primary intermediates i.e. metal superoxides and superoxide anion on Au(111) and Au(211). We elucidate the influence of electric fields and the importance of including explicit solvents on the adsorption energy of these intermediates. We show that these effects are considerable and should be included for future reaction modeling of these batteries. Following this we investigate the reaction of M⁺ and O …

Multi-Component Material For Solar Energy Conversion And Fundamentals Of Lead Acid Batteries, Crystal Ferels

Graduate Research Theses & Dissertations

Synthesis of complex inorganic materials is desirable because their complex composition allows more degrees of freedom and tunability, whose properties differ from their parent components. As an expansion on this concept, we synthesized a quinary compound Ce3FeWS3O6, using a molten flux method and a solvothermal method. The compound crystallizes into a hexagonal crystal system with space group P63/m. Its electric partition shows an anion with the form [(Ce3+)3W6+(S2-)3(O2-)6]3- forcing the transition metal Fe3+ state and leaving no conduction electrons, making the material a semiconductor. This compound is the right candidate as photoelectric material capable of absorbing photons from the solar …

Application Of Immobilized Palladium Monolithic Catalysts In Suzuki-Miyaura And Tsuji-Wacker Redox Reactions, Sajjad Ghobadi

Theses and Dissertations

Herein, a wholistic analysis of the viability of monolithic catalysts for redox reactions is presented. The interdisciplinary approach taken in this systematic study included preparation and investigation on Pd-on-carbon monoliths as catalysts in a flow and electrochemical settings.

The Suzuki-Miyaura reaction-focused study led to rational design, preparation, and successful application of Pd⁰-on-graphene oxide (GO) monolithic catalysts in flow conditions. In this study a combination of chemical reduction, freeze-casting, and vapor-phase reduction processes was applied to Pd-GO structures leading to the preparation of these monoliths. The Suzuki flow synthesis reactions revealed that the monolithic structure led to significantly improved …

Transition Metal Chalcogenide Hybrid Systems As Catalysts For Energy Conversion And Biosensing, Siddesh Umapathi

Doctoral Dissertations

"Generation of hydrogen and oxygen through catalyst-aided water splitting which has immense applications in metal air batteries, PEM fuel cells and solar to fuel energy production, has been one of the critical topics in recent times. The state of art oxygen evolution reaction (OER), oxygen reduction reaction (ORR), hydrogen evolution reaction (HER) catalysts are mostly comprised of precious metals. The current challenge lies in replacing these precious metal-based catalysts with non-precious earth-abundant materials without compromising catalytic efficiency.

This research explores mixed metal selenides containing Fe-Ni, Fe-Co and RhSe which were hydrothermally synthesized and/or electrodeposited and tested for OER and ORR …