Chemical Engineering Commons^™

Metal Organic Frameworks With Carbon Black For The Enhanced Electrochemical Detection Of 2,4,6-Trinitrotoluene, Shaghraf Javaid, Muhammad R. Azhar, Xinyu Li, Juliette I. Phillips, Tanveer Hussain, Hussein Abid, Jun Chen, Xiaobo Ji, Debbie S. Silvester

Research outputs 2022 to 2026

The sensing of explosives such as 2,4,6-trinitrotoluene (TNT) directly at an explosion site requires a fast, simple and sensitive detection method, to which electrochemical techniques are well suited. Herein, we report an electrochemical sensor material for TNT based on an ammonium hydroxide (NH4OH) sensitized zinc-1,4–benzenedicarboxylate Zn(BDC) metal organic framework (MOF) mixed with carbon black on a glassy carbon electrode. In the solvent modulation mechanism, by merely changing the concentration of NH4OH during synthesis, two Zn(BDC) MOFs with novel morphologies were fabricated via a hydrothermal approach. The as-prepared MOFs were characterized using X-ray powder diffraction (XRD), scanning electron microscopy (SEM), Fourier …

Band Alignments Of Metal/Oxides-Water Interfaces Using Ab Initio Molecular Dynamics, Yong-Bin Zhuang, Jun Cheng

Journal of Electrochemistry

Band alignments of electrode-water interfaces are of crucial importance for understanding electrochemical interfaces. In the scenario of electrocatalysis, applied potentials are equivalent to the Fermi levels of metals in the electrochemical cells; in the scenario of photo(electro)catalysis, semiconducting oxides under illumination have chemical reactivities toward redox reactions if the redox potentials of the reactions straddle the conduction band minimums (CBMs) or valence band maximums (VBMs) of the oxides. Computational band alignments allow us to obtain the Fermi level of metals, as well as the CBM and VBM of semiconducting oxides with respect to reference electrodes. In this tutorial, we describe …

From Waste To Energy: The Electrochemical Reduction Of Co2 Using Recycled Nanostructured Catalysts, Ibrahim Badawy

Theses and Dissertations

The reduction of carbon dioxide (CO₂RR) using electrochemistry is a promising solution for the burgeoning global energy crisis. The overall vision of its implementation relies on renewable energy sources to power the reaction creating carbon neutral products and effectively closing the carbon cycle. Research in this field has come a long way since its inception in the mid-1900s. However, there remain significant hurdles and important considerations to overcome in order to reach full commercialization. Most electrocatalysts tested for CO₂RR have been designed solely for maximum performance while ignoring the environmental consequences if such a material were …

The Study Of Corrosion On Additive-Manufactured Metals., Braydan Daniels

Electronic Theses and Dissertations

The purpose of this study was to investigate and compare the corrosion mechanisms between wrought and additive-manufactured (3D-printed) copper and stainless steel. The experimental procedure consisted of measuring the open circuit potential, electrochemical impedance spectroscopy, linear sweep voltammetry, Tafel analysis, surface topology, and scanning electron microscopy for each metal within salt water, tap water, sulfuric acid, and synthetic body fluid (excluding copper in synthetic body fluid).

Overall, printed stainless steel was more corrosion-resistant than wrought stainless steel in tap water and synthetic body fluid based on OCP, LSV, and surface topology results. Additionally, printed copper was more corrosion-resistant than wrought …

Faceted Nanomaterial Synthesis, Characterizations And Applications In Reactive Electrochemical Membrane Filtration, Qingquan Ma

Dissertations

Facet engineering of nanomaterials, especially metals and metal oxides has become an important strategy for tuning catalytic properties and functions from heterogeneous catalysis to electrochemical catalysis, photocatalysis, biomedicine, fuel cells, and gas sensors. The catalytic properties are highly related to the surface electronic structures, surface electron transport characteristics, and active center structures of catalysts, which can be tailored by surface facet control. The aim of this doctoral dissertation research is to study the facet-dependent properties of metal or metal oxide nanoparticles using multiple advanced characterization techniques. Specifically, the novel atomic force microscope-scanning electrochemical microscope (AFM-SECM) and density functional theory (DFT) …

New Solid Polymer Electrolytes For Lithium, Sodium, And Calcium-Based Batteries, Francielli Silva Genier

Dissertations - ALL

The establishment of sustainable energy sources highly depends on efficient storage devices to guarantee a consistent power supply. The growing demand for lithium-ion batteries (LIBs) for this purpose, combined with concerns about lithium availability, has motivated the search for viable storage alternatives, such as sodium and calcium. While several studies have investigated different lithium-free liquid electrolytes, the transport of these alternative ions in their polymer counterparts remains understudied. The advantages of solid polymer electrolytes include the possibility of higher energy density in solid-state devices and the elimination of safety concerns associated with liquid electrolytes, such as flammability, leakage, and dendrite …

Materials And Interfaces For Electrocatalytic Hydrogen Production And Utilization., Alexander Jiya Gupta

Electronic Theses and Dissertations

Mass industrialization over the last few centuries has created a global economy which is dependent upon fossil fuels to satisfy an exponentially increasing demand for energy. Aside from the possible depletion of this finite resource, the combustion of fossil fuels releases greenhouse gases into the atmosphere which cause the global temperature to rise – a phenomenon which has already begun to create geologic and geopolitical instability and shows no signs of abatement. One proposed method to rid humanity of its dependence on fossil fuels is to use green hydrogen as an energy carrier. In this scheme, excess electricity from a …

Highly Active And Stable Low-Pgm And Pgm-Free Catalysts For Anion Exchange Membrane Fuel Cells, Horie Adabi Firouzjaie

Theses and Dissertations

Anion exchange membrane fuel cells (AEMFCs) have recently seen significant growth in interest as their achievable current density, peak power density, and longevity have been dramatically improved. Though these advances in performance have been important for demonstrating the feasibility of the technology, nearly all AEMFCs reported in the literature have required a relatively high loading of platinum group metal (PGM)- based catalysts at both the anode and cathode electrodes. However, to take command of the low-temperature fuel cell market, AEMFCs cannot simply reach the same performance as incumbent proton exchange membrane fuel cells (PEMFCs), which have had decades of development …

Electroanalytical Measurements Of Oxide Ions In Molten Cacl2 On W Electrode, Devin Rappleye, Chao Zhang, Art Nelson, Scott Simpson, Michael Simpson

Faculty Publications

The electrochemical interaction of oxide ions with tungsten electrodes in molten calcium chloride (CaCl₂) was analyzed by combining electroanalytical techniques with X-ray photoelectron spectroscopy. During a cyclic voltammetry (CV) scan, the oxide ions appear to interact with the tungsten working electrode via a multi-step oxidation and reduction process. The overall redox peaks behave reversibly up to 750 mV/s. This electrochemical process enables the oxide ion concentration to be correlated to CV oxidation peaks. The resulting correlation agrees well (8.8% difference) with back titration measurements and can be used to monitor oxide content in the salt in real-time during …

The Study Of Copper Corrosion Mechanisms Using Electrochemical Experimental Techniques., Evan Grimm

Electronic Theses and Dissertations

The purpose of this study was to discover and thoroughly explain the corrosion mechanisms of copper in saltwater, tap water and deionized water, and to apply these methods and findings when testing the corrosion mechanisms of other materials. The experimental procedure consisted of measuring the open circuit potential, electrochemical impedance spectroscopy, linear sweep voltammetry, and Tafel analysis.

The copper was found to corrode at a greater rate in saltwater, followed by tap water then deionized water, with a larger difference between saltwater and tap water than between tap water and deionized water. Each reaction was found to be both kinetically …

Modified Electrode Surfaces With Hydrogen Evolution Reaction Catalysts Derived From Electropolymerized Complexes With Redox Active Ligands., Amanda Mae Arts

Electronic Theses and Dissertations

The demand for energy is growing exponentially, and to keep up with these demands new technologies for renewable energy have received increased attention. Hydrogen is one of the most promising energy sources for the future and plays a vital role in water electrolysis and fuel cells, as the hydrogen evolution reaction (HER) is the main step in the water splitting process. To increase the reaction rate and improve efficiency for the water electrolysis, catalysts are used to minimize the overpotential.

Most of the current electrocatalysts for HER are heterogeneous in nature and are dominated by platinum and other precious metals …

The Controlled Synthesis Of Hydrogen Electrocatalysts For Alkaline Exchange Membrane Fuel Cell And Electrolysis Applications Via Chemical Vapor Deposition, Stefan Thurston Dubard Williams

Doctoral Dissertations

The development of catalysts for the electrochemical processes of hydrogen systems (e.g., fuel cells and electrolyzer systems) continues to be an attractive area of research for renewable energy technologies. One significant challenge has been developing hydrogen catalysts suitable for alkaline environments, mainly due to the sluggish kinetics of hydrogen reactions. In alkaline environments, the kinetics are decreased by two orders of magnitude when compared to acidic environments. Chemical vapor deposition (CVD) is a conventional method used to synthesize these types of catalysts. This effort discusses extending work being done using a modified CVD process known as “Poor Man’s” CVD (PMCVD) …

Mitigating Corrosion And Enhancing Energy Density Of Zinc-Based Anodes In Primary And Secondary Aqueous Batteries, Ehsan Faegh

Theses and Dissertations

Today Lithium-ion (Li-ion) batteries are the most-emphasized battery technology among the many different battery systems in the market. However, due to their high cost (especially for electric vehicle applications), flammability and toxicity, the development of inexpensive and safer alternative battery chemistries has been the focus of a significant amount of recent research. Among various battery chemistries, Aluminum-based (Al-based) and Zinc-based (Zn-based) batteries have been touted as promising options to compete with Li-ion batteries. However, the practical realization of Al battery chemistries has been difficult over a long period of time (170 years) due to a number of fundamental and intrinsic …

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 …

Carbon Capture And Utilization, Sriram Valluri

Dissertations, Master's Theses and Master's Reports

As the world moves towards clean energy initiative, carbon capture and utilization technologies are key to achieving net zero emissions. CO2 capture with amines has many disadvantages and cannot be applied to commercial power plants. The current manuscript will address this issue as well as a solution that involves the use of low-cost alkali absorbent CO₂ capture solutions, combined with an electrochemical regeneration method that uses the least amount of energy available for capture and regeneration. This research will also further address the issue of how to deal with the captured CO2. Several viable storage and utilization methods have …

Investigation Of Iron-Nickel Based Nanoparticles As Catalysts For Oxygen Evolution Reaction (Oer), Prashant Acharya

Graduate Theses and Dissertations

Hydrogen fuel is increasingly seen as an appealing alternative by both the scientific and the industrial communities in the drive towards a clean energy future. Hydrogen, unlike fossil-based fuels, does not release carbon dioxide, a chief component of greenhouse gases, upon combustion. However, more than 95% of the hydrogen in the world is still produced by burning fossil fuels as this method is currently the only economically feasible option at a large industrial scale.

Water electrolysis shows a lot of potential in both hydrogen generation and in the storage of energy from renewable sources such as wind and sunlight. Likewise, …

Cold Plasma Enhanced Active Sites On Supported Nip Nanoparticles For The Oxygen Evolution Reaction, Michael Ricci

Williams Honors College, Honors Research Projects

Identifying materials to efficiently facilitate the oxygen evolution reaction (OER) is key to advancing water electrolysis, an essential technology in the pathway towards a sustainable energy future. Here, we explore cold-plasma treatment as a facile method to enhance the activity of NiP nanoparticles supported on activated carbon. NiP nanoparticles were synthesized on an activated carbon support using a solid-state method and were then treated with argon, oxygen, and hydrogen plasmas for extended times. In all cases, plasma treatment reduced the number of active sites on the support. OER activity was evaluated by testing the materials in alkaline conditions. The activities …

Biomass-Derived Electrode Materials And Sustainable Processes For Supercapacitors, Katelyn M. Shell

Theses and Dissertations

Biomass is one of the most abundant natural resources and has been used as a source of energy for thousands of years. Biomass as a precursor for energy storage materials is still relatively novel and faces several obstacles before becoming commonly used in today’s electrical devices. Currently, energy storage devices, such as batteries, capacitors, and supercapacitors, utilize petroleum-derived graphitic carbons for anodes, generating a need for more sustainable materials. Biomass, as a carbon-rich source for electrode materials, presents a viable and economically feasible alternative due to the prevalent lignocellulosic compounds: lignin, cellulose, and hemicellulose. Preliminary studies on the solid residues …

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 …

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 …

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 …

Anion Exchange And Bipolar Membranes For Electrochemical Energy Conversion And Storage, Zhongyang Wang

McKelvey School of Engineering Theses & Dissertations

Anion exchange and bipolar membrane fuel cells generate electrical energy directly from chemical fuels and have attracted considerable interests as alternate power sources for large market applications, such as transportation (hydrogen fuel cells) and unmanned vehicles (sodium borohydride fuel cells). Anion exchange membrane (AEM), generally composed of a polymer with covalently tethered ionic groups, is the central component of the fuel cell serving as the electrolyte, conducting hydroxide ions from cathode to anode, where fast ionic conduction is directly related to power output. However, AEMs currently used in fuel cells (H2 fuel cells and sodium borohydride fuel cells) exhibit ion …

Surface Immobilization Of Terpyridine Compounds, Elizabeth Hallett

Chemical Engineering Undergraduate Honors Theses

The deoxydehydration (DODH) of polyols to alkenes is a promising method of producing high-value chemical feedstocks from biomass-derived materials. Current catalytic systems for DODH require the use of costly reducing agents that generate stoichiometric amounts of chemical waste. Immobilizing catalysts on electrode surfaces using chemical linking groups eliminates the need for sacrificial reductants. In this work, glassy carbon electrodes were modified with 4’-(3,4-dihydroxyphenyl)-2,2’:6’,2’’-terpyridine to investigate o-benzoquinone as a potential linking group for DODH, and possibly for other reactions. Previous studies involving electrodes modified with quinone-containing compounds have primarily been focused on catalyzing the oxidation of NADH; the nature or …

An Experimental And Numerical Investigation Of Flow Accelerated Flibe Corrosion, David B. Weitzel

Nuclear Engineering ETDs

Renewed interest in molten salt reactor technology has brought to light the need for a better understanding of FLiBe corrosion. To this end a flowing FLiBe corrosion test loop was designed to test the flow effects of FLiBe corrosion. The loop consists of a pump, melt tank, and stainless-steel tubing assembly that heats the molten salt to high temperatures and circulates it over test specimens. The experiment has been constructed and has completed initial shakedown testing.

To support the flowing FLiBe experiment, a numerical corrosion model that couples FLiBe electrochemistry, solid metal diffusion, and mass transport was implemented. The model …

Engineering Of Earth-Abundant Electrochemical Catalysts, Dylan D. Rodene

Theses and Dissertations

Alternative energy research into hydrogen production via water electrolysis addresses environmental and sustainability concerns associated with fossil fuel use. Renewable-powered electrolyzers are foreseen to produce hydrogen if energy and cost requirements are achieved. Electrocatalysts reduce the energy requirements of operating electrolyzers by lowering the reaction kinetics at the electrodes. Platinum group metals (PGMs) tend to be utilized as electrocatalysts but are not readily available and are expensive. Ni_1-xMo_x alloys, as low-cost and earth-abundant transition metal nanoparticles (NPs), are emerging as promising electrocatalyst candidates to replace expensive PGM catalysts in alkaline media. Pure-phase cubic and hexagonal Ni_{1-x …}

Chronoamperometry Analysis Of Sweat Sensor Technology, Evan Fritz

Williams Honors College, Honors Research Projects

Due to the demand for in-situ electrolyte sodium sensors, prototype sensors have been produced to create a product for athletes and marathoners to monitor hydration levels. These senors address a desire in the marketplace for athletic monitoring for overall athlete wellness and performance. Sweat sensor samples were created using Multi-walled Carbon Nanotubes functionalized on a Nylon-6 fiber mat using cyclo-oligomeric Calixarene. This production process produces sensors capable of detecting sodium ion concentration present in human sweat in presence of an electric current. Chronoamperometry analysis is used in this manner to determine the functionality of the sensors. Much of the research …

Spectro-Electrochemical Platforms For Dynamic Analyses Of Catalytic Cascade Systems, Nalin I. Andersen

Nanoscience and Microsystems ETDs

The development of spectro-electrochemical platforms that facilitate the dynamic analyses of complex catalytic cascade systems was explored in this research. These systems facilitated multiple modalities of catalysts and were used as platforms for monitoring catalytic transformations quasi-in situ. The analytical platforms allowed for the characterization of intermediates and products using surface-enhanced Raman spectroscopy (SERS). The design and fabrication of these devices proved to be reproducible, made of materials that can be manipulated for multiple applications, and incorporate fluid mechanics, electrochemistry, and multimodal catalysis. Microfluidic technology offers capabilities for understanding catalytic cascade systems by providing precise dynamic control of …

Vanadium Redox Flow Batteries: Design And Experimentation, Matthew George

Williams Honors College, Honors Research Projects

Vanadium flow batteries (VFB) are a type of battery that has potential as a grid-scale energy storage solution. An original design for a lab-scale VFB is presented herein, along with a procedure for electrolyte preparation from V₂O₅ using oxalic acid. The flow cell is constructed from Delrin, Teflon, Kynar, Santoprene, Nafion, graphite plate, and porous carbon. Two diaphragm pumps along with polyethylene, PVC, and Santoprene tubing are used. The active area is 58 cm². The battery was charged using a DC power supply at a constant current of 4 A with corresponding initial voltage of …