Materials Chemistry Commons^™

Investigation Of Space Charge Effects On Co2 Electrocatalytic Reduction On Gd-Doped Ceria Via Scanning Kelvin Probe And Model-Based Bayesian Analysis, Alejandro Mejia

Graduate Theses, Dissertations, and Problem Reports

In studying novel energy conversion and storage systems, such as high-temperature electrolysis, numerous underlying fundamental physical processes remain unclear or inadequately understood. Among these, the modeling and comprehension of surface reaction mechanisms, coupled with the intricate effects of space‑charge interfaces, remains an unclear and challenging area of research.

The work of this dissertation involves the development of a 2D finite element analysis model, leveraging the robust MOOSE framework from INL. This model, featuring inhomogeneous defect thermodynamics for near-surface chemistry, formulated through Poisson‑Cahn variational theory, has been exploited for studying the electrocatalytic reduction of CO₂ on gadolinia doped ceria. The …

Experimental And Simulation Study Of Reactive Silver Ink Droplet Evaporation, Weipeng Zhang

Electronic Thesis and Dissertation Repository

The evaporation of particle-free silver ink droplets on heated substrates directly impacts the morphology of the resultant silver particles and films. In this thesis, COMSOL Multiphysics simulations of the solvent (water-ethylene glycol mixture) droplet evaporation process are used to explain the microflows, mass transfers, and heat distribution responsible for the experimental observations. The reactive ink incorporates fluoro-surfactant FS-31 and poly (acrylamide) (PAM) to suppress the coffee-ring effect that negatively impacts the electrical conductivity. Experiments show that the droplet evaporation process results in varied silver particle morphology, depending on the locations within the droplet, leading to uneven surfaces. Large particles (3 …

Corrosion Case Study On Pipeline, Kangze Ren

Corrosion Research

The Kashagan pipeline leaks were likely caused by sulfur stress corrosion cracking, a combined corrosion mechanism developed by the presence of high pressure, the high level of hydrogen sulfide(the main "ingredient" of sour gas), and poor metallurgical choice. Improper welding and poor metallurgical examination were blamed for causing the leaking issue. The purpose of the current review is to raise the alarm about the inappropriate corrosion management of Kashagan oil production and its societal and environmental consequences.

Synthesis And Characterization Of Sodium Cathode Materials, He Zhou

McKelvey School of Engineering Theses & Dissertations

As sodium batteries hold great promise as a next-generation energy storage device to replace lithium batteries, the development of sodium battery materials has become increasingly urgent. The current study aims to investigate two potential sodium-ion battery cathode materials, Sodium Vanadium Phosphate, and Sodium Manganese Hexacyanoferrate, optimize the experimental procedures, conduct a systematic analysis of material properties and characterization, and ultimately determine the ideal synthesis conditions for these materials.

In the first part of the study, we focused on optimizing the synthesis of Sodium Vanadium Phosphate. By investigating various synthesis conditions, such as annealing temperature, pressure, ascorbic acid content, and material …

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 …

Intergranular And Pitting Corrosion Mechanisms Of Sensitized Aluminum Alloy Aa5083, Clayton Egleston

Williams Honors College, Honors Research Projects

The motivation and objectives of this project is to examine the mechanisms of intergranular corrosion (IGC) and pitting corrosion of sensitized AA5083. In this regard, different characterization techniques were used, including optical analysis of microstructure, cyclic potentiodynamic polarization with Tafel fitting, electrochemical impedance spectroscopy with electrical equivalent circuit (EEC) fitting, and potentiostatic current transient monitoring. The transition from IGC to pitting corrosion occurs when the grain boundaries become saturated with the β-phase (Mg₂Al₃). It was found that AA5083 becomes more vulnerable to pitting corrosion as the degree of sensitization increases.

Wetting Transition Of Texturized Surfaces, Jenna Stephens

Williams Honors College, Honors Research Projects

Building on previous research, this project aims to continue the investigation of the wettability of various liquids on a uniform, texturized surface. Different surface energies can impact the wettability of a surface. The surface can be hydrophilic, hydrophobic, or in between. The goal of this project is to research how features of texturized surfaces affect the wetting transition of water, oil, and a mixture of both. Additionally, this project aims to improve the quality of the 3D printed surfaces. The surfaces that will be studied are constructed using UV cured resin 3D printing and are made up of an array …

Near-Ir Laser Ablation Of Simulated Radiologically Contaminated Oxides On Carbon Steel Feeder Pipes, Thao Viet Do

Electronic Thesis and Dissertation Repository

As nuclear power plants age and retire from service, many countries face significant challenges concerning the safe long-term storage and disposal of large volumes of low and intermediate level radioactive wastes (L&ILW). The volumes of metallic waste are of particular concern, as when metal corrodes it produces hydrogen that could lead to pressure build-up in interim storage and disposal. In Canada, a significant fraction of the metallic wastes for Canada Deuterium Uranium (CANDU) nuclear reactors are out-of-core reactor components, such as carbon steel (CS) feeder pipes. The radioactive contamination is expected to be largely confined to the surface oxide layers …

Solid Electrolytes And Interface Design For High-Performance All-Solid-State Batteries, Shumin Zhang

Electronic Thesis and Dissertation Repository

All-solid-state batteries (ASSBs), in which solid superionic conductors are used as electrolytes to transport ions between cathode and anode, have been regarded as one of the most promising candidates for the next-generation energy storage technologies in electric vehicles (EVs), grid applications, etc. The advances of ASSBs over conventional lithium-ion batteries (LIBs) come from their inherent safety and high energy density, which benefits from the use of nonflammable solid electrolytes (SEs) to potentially enable metal anodes (such as Li metal or Na metal) and high-voltage cathode active materials (CAM) in ASSBs. Since that, the research and design of SEs have been …

A Modular Synthesis Of Processable And Thermally Stable Semi-Fluorinated Aryl Ether Polymers Via Step-Growth Polymerization Of Fluoroalkenes, Ketki Eknath Shelar

Theses and Dissertations

Tailored fluoropolymers remain the leading choice for a wide variety of advanced high-performance applications, including electronic/optical and energy conversion, owing to their unique blend of complementary high-performance properties. Amorphous semi-fluorinated polymers exhibit improved solubility and melt processability when compared to traditional perfluoropolymers. A leading class of semi-fluorinated aryl ether polymers includes perfluorocyclobutyl (PFCB), perfluorocycloalkenyl (PFCA), and fluoroarylene vinylene ether (FAVE) polymers. Monomers containing aromatic trifluorovinyl ethers (TFVE) are used to synthesize PFCB polymers via radical-mediated [2+2] cyclodimerization. On the other hand, FAVE and PFCA polymers are polymerized via base-mediated nucleophilic addition/elimination of bisphenols with TFVE monomers and decafluorocyclohexene respectively. The …

Design And Fabrication Of Nanostructured Electrodes For Complementary Electrochemical And Photoelectrochemical Water Splitting, Kholoud El Sayed Abousalem

Theses and Dissertations

Designing highly active, durable, and nonprecious electrodes for overall water splitting is of urgent scientific importance to realize sustainable hydrogen production. Accordingly, the need to search efficient energy production systems is of crucial necessity. In this thesis, two various systems for sustainable hydrogen production have been reported using electrochemical and photoelectrochemical pathways. In the first part of the thesis, electrochemical water splitting involving both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) has been established. To this end, an innovative approach is demonstrated to synthesize flower-like 3D homogenous trimetallic Mn, Ni, Co phosphide catalysts directly on nickel foam via …

Development Of Advanced Solid-State Electrolytes And Interfaces For High-Performance Sulfide-Based All-Solid-State Lithium Batteries, Feipeng Zhao

Electronic Thesis and Dissertation Repository

All-solid-state lithium batteries (ASSLBs) have become increasingly attractive due to the demand of high-energy-density and high-safety lithium-ion batteries for electric vehicles (EVs). As the core component of ASSLBs, solid-state electrolytes (SSEs) are regarded as essential to determine the electrochemical performance of ASSLBs. The inorganic SSEs is one of the most important categories in all developed SSEs, representing the advance of superionic lithium conductors as well as the cornerstone to construct flexible polymer/inorganic composite SSEs. The sulfide-based inorganic SSE is one of the most promising SSEs that is receiving a lot of attentions, because only sulfide SSEs can show ultrahigh ionic …

Degumming Of Hemp Fibers Using Combined Microwave Energy And Deep Eutectic Solvent, Bulbul Ahmed

LSU Master's Theses

Hemp is considered as one of the sustainable agricultural fiber materials. Degumming or surface modification of hemp bast is needed to produce single fibers for ensuing textile and industrial applications. The traditional degumming process necessitates a high amount of alkali, which causes detrimental environmental pollution. This study offers a new method to degum hemp fibers with reduced use of harmful alkali and precious water resources. In this work, hemp bast fibers were degummed by using combined microwave energy and deep eutectic solvent (DES). The properties of hemp fibers manufactured by this method were investigated and compared with the traditional alkali …

Development Of Synthetic Coal Char Simulant For Microwave Conversion Studies: A Computationally-Driven Approach, Kevin A. Hager

Graduate Theses, Dissertations, and Problem Reports

Recent experimental demonstration of new reaction windows for coal char/methane reactions that are less energy-intensive, provides innovation for modular reactors. However, the correlation of the exact mechanism for the enhancement of these reaction windows is not certain. This study investigates the simplification of these experimental studies by developing a well-characterized coal char simulant. The approach involves using a computational approach to screen macroscopic composition to replicate the dielectric and compositional response of actual char. This study is focused on PRB coal char. A discrete element method (DEM) technique was used to simulate the packing of coal chars to give the …

Treated Hfo2 Based Rram Devices With Ru, Tan, Tin As Top Electrode For In-Memory Computing Hardware, Yuvraj Dineshkumar Patel

Theses

The scalability and power efficiency of the conventional CMOS technology is steadily coming to a halt due to increasing problems and challenges in fabrication technology. Many non-volatile memory devices have emerged recently to meet the scaling challenges. Memory devices such as RRAMs or ReRAM (Resistive Random-Access Memory) have proved to be a promising candidate for analog in memory computing applications related to inference and learning in artificial intelligence. A RRAM cell has a MIM (Metal insulator metal) structure that exhibits reversible resistive switching on application of positive or negative voltage. But detailed studies on the power consumption, repeatability and retention …

Local Structure And Dynamic Studies Of Mixed Ch4-Co2 Gas Hydrates Via Computational Simulation And Neutron Scattering, Bernadette Rita Cladek

Doctoral Dissertations

Permeated throughout the ocean floor and arctic permafrost, natural gas hydrates contain an estimated 3000 trillion cubic meters, over three times that of traditional shale deposits, of CH₄ that is accessible for extraction. Gas hydrates are a crystal structure in which water molecules form a cage network, the host, through hydrogen bonds while trapping a guest molecule such as CH₄ in the cavities. These compounds form naturally where the appropriate low temperature and high pressure conditions occur. A promising and tested method of methane recovery is through exchange with CO₂, which energetically takes place of the …

Resource-Saving Technologies For The Production Of Elastic Leather Materials: Collective Monograph, Olena Korotych, Anatolii Danylkovych, Serhii Bilinskyi, Serhii Bondarenko, Slava Branovitska, Vasyl Chervinskyi, Nataliia Khliebnikova, Alona Kudzieva, Viktor Lishchuk, Nataliia Lysenko, Olena Mokrousova, Nataliia Omelchenko, Vera Palamar, Yuliia Potakh, Oksana Romanyuk, Olga Sanginova, Oleksandr Zhyhotsky

Chemistry Publications and Other Works

This monograph contains a collection of recent research papers focusing on advancing existing technologies and developing new technologies to improve the environmentally friendliness and save resources during the production of elastic leather materials. The papers are organized based on the type of technological process used to preserve raw hides. A lot of attention is devoted to mathematical planning, simulations, and multicriteria optimization of the technological processes using newly developed chemical reagents. The monograph contains a complex study of physicochemical properties and characteristics of the resulting leather materials. The developed technologies were tested by the private joint-stock company Chinbar (Kyiv, Ukraine) …

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 …

Enhancement Of Phase Change Material Sorbitol By Nanoparticle Inclusion For Improving Thermal Energy Storage Capabilities, Joshua Kasitz

Mechanical Engineering Undergraduate Honors Theses

Thermal management of electronic devices has become an increasingly vital field of study with the rapid miniaturization of many key electrical components. With the significant improvement of semiconductor manufacturing and intensified focus on interconnects, electronic devices have decreased in size at an incredible rate. Decreasing spatial requirements is essential to improving device capabilities as the electronic system is able to incorporate more components. Currently, electronic systems are drastically limited by the capabilities of their cooling mechanisms. Smaller devices lead to large increases in the energy density of the system and require more powerful cooling systems to maintain proper component operating …

Study Of Amorphous Boron Carbide And Hydrogenated Boron Carbide Materials Using Molecular Dynamics And Hybrid Reverse Monte Carlo, Rajan Khadka

MSU Graduate Theses

We present a computational study of amorphous boron carbide (a-B_xC) models using Molecular Dynamics (MD) studied with Stillinger-Weber (SW) and ReaxFF potential. The atomic structure factor (S(Q)), radial distribution function (RDF) and bond lengths comparison with other experimental and ab initio models shows that a random arrangement of icosahedra (B₁₂, B₁₁C) interconnected by chains (CCC, CBC) are present in a-B_xC. Afterward, Hybrid Reverse Monte Carlo (HRMC) technique is used to recreate a-B_xC structures. The existing SW potential parameters of Boron are optimized for the α-rhombohedral (Icosahedral B_{12 …}

Shape-Controlled Nanoparticles As Effective Catalysts For Proton Exchange Membrane (Pem) Fuel Cells, Ali Feizabadi

Electronic Thesis and Dissertation Repository

Polymer electrolyte membrane fuel cell (PEMFC), is considered a promising candidate for the next generation power sources in transportation, stationary and portable applications. However, oxygen reduction reaction (ORR), one of the key reactions occurring on PEMFC is kinetically slow; this has limited performance and further advancement in this kind of fuel cells. Thus, improving the PEMFC efficiency requires a thorough understanding of the ORR mechanism on the desired catalyst. To address the above-mentioned demands, the scope of this thesis is focused on the fundamental understanding of facet-controlled nanoparticles, metal-support interactions, and bimetallic platinum catalysts, utilizing synchrotron-based X-ray absorption, X-ray photoelectron …

Nano Fab Lab 63, Brian K. Deemer, Josh Clemons, Nick Brodine, Delaney Fitzsimmons

Mechanical Engineering

Lawrence Livermore National Laboratories (LLNL) has several steps in the production process for ceramic nanofiber tubes that they would like to improve - electrospinning, cutting, rolling, sealing and heat treating. We undertook the challenge to deliver LLNL with a semi-automated process that efficiently integrates the steps of cutting, rolling, and sealing to save time and improve control over end dimensions. In this document, we discuss the technical background of the manufacturing steps currently followed to create nanofiber tubes, identify which steps are incorporated in our prototype and explain how they will interface with one another, define the design requirements, present …

Application Of X-Ray Grating Interferometry To Polymer/Flame Retardant Blends In Additive Manufacturing, Omoefe Joy Kio

LSU Doctoral Dissertations

X-ray grating interferometry is a nondestructive tool for visualizing the internal structures of samples. Image contrast can be generated from the absorption of X-rays, the change in phase of the beam and small-angle X-ray scattering (dark-field). The attenuation and differential phase data obtained complement each other to give the internal composition of a material and large-scale structural information. The dark-field signal reveals sub-pixel structural detail usually invisible to the attenuation and phase probe, with the potential to highlight size distribution detail in a fashion faster than conventional small-angle scattering techniques. This work applies X-ray grating interferometry to the study of …

Molecular Assembly Of Monolayer-Protected Gold Nanoparticles And Their Chemical, Thermal, And Ultrasonic Stabilities, Steven Ray Isaacs

Masters Theses & Specialist Projects

Gold monolayer-protected nanoclusters (MPCs) with average diameters of 1-5 nm protected by alkane- and arenethiolates were synthesized. Mixed-monolayer protected nanoparticles (MMPCs) were prepared by functionalizing hexanethiolate-protected MPCs with either 11-mercaptoundecanoic acid (MUA-MMPC), 11-mercaptoundecanol (MUO-MMPC), or 4-aminothiophenol (ATP-MMPC) using ligand place exchange. Presentation of various chemical reagents such as nucleophile, acid, or base and change in physical environment through ultrasonic and thermal irradiation resulted in changes to particles and their physical properties. Thermogravimetric analysis (TGA) was used to measure maximum temperature of the derivated thermogravimetric peaks (Tmax,DTG) as a means of comparing temperature dependence of mass loss. The absorption spectrum within …

Feco2o4 As An Anode Material For Lithium Ion Batteries, Chelsea Wong

The International Student Science Fair 2018

Lithium ion batteries (LIBs) are commonly found in many portable electronic appliances due to their ability to be rechargeable. Currently, commercial anodes in Li-ion batteries (graphite) have a theoretical capacity of around 372 mAh/g, while FeCo2O4 that will be investigated as the anode material has a theoretical capacity of 901.985mAh/g, more than double of the current commercial anode’s capacity. Earlier work done by Sharma et al also showed that FeCo2O4 has a very promising initial capacity of 827mAh/g. As such, the engineering goal is to produce a battery that will have a higher capacity than the current commercial Li-ion batteries …

Feco2o4 As An Anode Material For Lithium Ion Batteries, Chelsea Wong

The International Student Science Fair 2018

Lithium ion batteries (LIBs) are commonly found in many portable electronic appliances due to their ability to be rechargeable. Currently, commercial anodes in Li-ion batteries (graphite) have a theoretical capacity of around 372 mAh/g, while FeCo2O4 that will be investigated as the anode material has a theoretical capacity of 901.985mAh/g, more than double of the current commercial anode’s capacity. Earlier work done by Sharma et al also showed that FeCo2O4 has a very promising initial capacity of 827mAh/g. As such, the engineering goal is to produce a battery that will have a higher capacity than the current commercial Li-ion batteries …

Interfacial Corrosion Of Copper And The Formation Of Copper Hydroxychloride, Mary Teague, Shengxi Li, Hongbo Cong

Williams Honors College, Honors Research Projects

Electrical circuitry is an industry, among many others, heavily using the element of copper. Ensuring the mechanical integrity of Cu is crucial, especially in salt environments, for the multifaceted composition of circuits. 4N NaCl solution (equilibrium concentration in ~84% RH) simulated this three-phase system. Rectangular Cu samples were partially immersed in both ambient and continuous lab air sparging atmospheres to understand waterline corrosion of the metal. Open circuit potentials (OCP) were continuously taken during the immersion testing for a maximum of 5 days. A scanning electron microscopy (SEM) equipped with an energy dispersive X-ray spectrometer (EDS), Raman spectroscopy, and 3-D …

Surfactant Driven Assembly Of Freeze-Casted, Polymer-Derived Ceramic Nanoparticles On Grapehene Oxide Sheets For Lithium-Ion Battery Anodes, Ali Zein Khater

Honors Undergraduate Theses

Traditional Lithium-Ion Batteries (LIBs) are a reliable and cost-efficient choice for energy storage. LIBs offer high energy density and low self-discharge. Recent developments in electric-based technologies push for replacing historically used Lead-Acid batteries with LIBs. However, LIBs do not yet meet the demands of modern technology. Silicon and graphene oxide (GO) have been identified as promising replacements to improve anode materials. Graphene oxide has a unique sheet-like structure that provides a mechanically stable, light weight material for LIB anodes. Due to its structure, reduced graphene oxide (rGO) is efficiently conductive and resistive to environmental changes. On the other hand, silicon-based …

Investigating Scalable Manufacturing Of High-Conductivity Wires And Coatings From Ultra-Long Carbon Nanotubes, Pouria Khanbolouki

Mechanical Engineering ETDs

Carbon nanotubes (CNTs) are a promising candidate for next generation of electrical wirings and electromagnetic interference (EMI) shielding materials due to their exceptional mechanical and electrical properties. Wires and coatings from ultralong nanotubes that are highly crystalline, well-aligned and densely packed can achieve this goal. High-performance CNT conductors will be relatively lightweight and resistant to harsh conditions and therefore can potentially replace current conductors in many industries including aerospace, automotive, gas and oil.

This thesis investigates a new manufacturing approach, based on conventional solution coating and wire drawing methods, to fabricate high conductivity wires and coatings from ultra-long carbon nanotubes. …

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 …