Chemical Engineering Commons^™

The Production Of Encapsulated Holy Basil Oil Powder Via Different Scales Of Spray Drying Process., Chanakarn Chungmarisakul

Chulalongkorn University Theses and Dissertations (Chula ETD)

The spray drying process is widely utilized in food manufacturing and pharmaceuticals for products like seasoning powder, milk powder, and medicine. This research investigates the scale-up of the spray drying process from laboratory to commercial scale with maintaining the product characteristic. A key aspect of the study is the encapsulation technique applied to prolong the release of essential oils from holy basil, encapsulating the essential substances (liquid, suspension, or emulsion) in nanoparticle form with hot air flow. The study utilizes the Aspen program, incorporating mass and energy balance calculations for simulation. The results, assuming similar particle size, water evaporation per …

Effects Of Confinement On Ionic Liquids And Deep Eutectic Solvents For The Design Of Catalytic Systems, Electrochemical Devices, And Separations, Andrew Drake

Theses and Dissertations--Chemical and Materials Engineering

Confinement of ionic liquids (ILs) and deep eutectic solvents (DESs) within mesoporous materials such as silica helps to control the local environment within the pores for applications such as catalysis, electrochemistry, and absorption. Silica thin films with 2.5 and 8 nm pores and micron-sized silica particles with pore diameters of 5.4 and 9 nm were synthesized to study the effect of nanoconfinement on ILs 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM][PF₆]), 1-butyl-3-methylimidazolium chloride ([BMIM][Cl]), and DESs reline and ethaline (choline chloride and urea or ethylene glycol). Silica thin films with vertically aligned, well ordered, and accessible pores were synthesized via the evaporation-induced …

Attrition Study Of Copper-Supplemented Iron-Based Oxygen Carrier For Chemical Looping Combustion, Neng Huang

Theses and Dissertations--Mechanical and Aerospace Engineering

Chemical looping combustion (CLC) is a promising technology that can mitigate the carbon emissions for power generation. The cost of oxygen carriers (OCs) impedes the scale up of CLC. Compared to synthetic iron-based OCs, red mud (RM), an abundant iron-based solid waste from industry, is a cost-effective choice due to its intrinsic inclusion of both inert and catalytic phases that are crucial for CLC. It was anticipated that the addition of copper oxide to RM using a mechanical mixing method that can be easily scaled up would enhance both reactivity and oxygen transport capacity (OTC), and the heat of reaction …

Impact Of Spallation And Internal Radiation On Fibrous Ablative Materials, Raghava Sai Chaitanya Davuluri

Theses and Dissertations--Mechanical and Aerospace Engineering

Space vehicles are equipped with Thermal Protection Systems (TPS) that encounter high heat rates and protect the payload while entering a planetary atmosphere. For most missions that interest NASA, ablative materials are used as TPS. These materials undergo several mass and energy transfer mechanisms to absorb intense heat. The size and construction of the TPS are based on the composition of the planetary atmosphere and the impact of various ablative mechanisms on the flow field and the material. Therefore, it is essential to quantify the rates of different ablative phenomena to model TPS accurately. In this work, the impact of …

Microalgae Immobilization With Filamentous Fungi: Process Development For Sustainable Food Systems, Suvro Talukdar

Theses and Dissertations--Biosystems and Agricultural Engineering

Demand for sustainable food sources has increased because of the rapid growth of the world's population.  In this study, microalgae cells of Haematococcus pluvialis were immobilized using the edible fungal strain Aspergillus awamori for potential food applications. The study investigated the impact of fungal loading, pellet geometry, and initial microalgae cell concentration on the immobilization performance and product characteristics. It was found that higher fungal loading and larger fungal pellets contributed to increased immobilization performance while increased initial microalgae concentration inhibited the process. Larger fungal pellets had decreased biomass density, which led to decreased surface concentration of immobilized microalgae but …

Natural Manganese Ores For Efficient Removal Of Organic Pollutants Via Catalytic Peroxymonosulfate-Based Advanced Oxidation Processes, Zhengxin Yao, Roufei Chen, Ning Han, Hongqi Sun, Ngie Hing Wong, Lusi Ernawati, Shaobin Wang, Jaka Sunarso, Shaomin Liu

Research outputs 2022 to 2026

Peroxymonosulfate-based advanced oxidation processes (PMS-AOPs) for in situ persistent organic pollutant (POP) remediation in aqueous solutions can be a promising technology. However, this technology is constrained by its high toxicity and cost of metal oxide and non-metal catalysts for PMS activation. Here, we investigated the catalytic performance of a widely available natural mineral, manganese ore (MO), for PMS activation. A series of natural MO samples in an aqueous solution were prepared via the Fenton-like reaction. The samples' crystalline structure, surface morphology, textural properties, and other surface characteristics of the selected MO were systematically characterized. The effects of PMS concentration and …

Heterogeneous Microstructure And Mechanical Behaviour Of Al-8.3fe-1.3v-1.8si Alloy Produced By Laser Powder Bed Fusion, S. J. Yu, P. Wang, H. C. Li, R. Setchi, M. W. Wu, Z. Y. Liu, Z. W. Chen, S. Waqar, Lai-Chang Zhang

Research outputs 2022 to 2026

The relationship between processing parameters, microstructure, and mechanical properties of Al-8.3Fe-1.3V-1.8Si alloy processed by laser powder bed fusion is seldom studied. Therefore, fully dense alloys with two parameters were selected to investigate this key issue. The results show that the alloy with low power and scanning speed (S200) shows fan-shell-shaped melt pools and laser tracks while another (S350) shows a deeper and wider melt pool. Both alloys obtain a heterogeneous microstructure without a secondary phase in melt pool (MP) and a nano-sized phase in melt pool boundary (MPB). The difference between solid-solution strengthening and Orowan strengthening in MP and MPB …

Experimental Investigation Of The Interface And Wetting Characteristics Of Rock-H2-Brine Systems For H2 Geological Storage, Mirhasan Hosseini

Theses: Doctorates and Masters

The projected rise in demand for hydrogen (H2) production is a response to several factors, including greenhouse gas emissions caused by burning fossil fuels, depletion of fossil fuel reserves, and their uneven distribution around the earth. Thus, increased requirement for large-scale hydrogen storage solutions is anticipated to overcome imbalance between energy demand and supply. Deep underground formations such as salt caverns and porous reservoir rocks (e.g., depleted hydrocarbon reservoirs and deep saline aquifers) are necessary to achieve such volumes in practice. This process is known as underground hydrogen storage (UHS) which is technically very similar to underground natural gas storage. …

Role Of Air Staging In A Batch-Type Fixed Bed Biomass Combustor Under Constant Primary Air, Awais Junejo, Yasir M. Al-Abdeli, Jacobo Porteiro

Research outputs 2022 to 2026

Staged combustion of biomass is the most suitable thermo-chemical conversion for achieving lower gaseous emissions and higher fuel conversion rates. In a staged fixed bed combustion of biomass, combustion air is supplied in two stages. In the first stage, primary air is provided below the fuel, whereas in the later stage, secondary air is supplied in the freeboard region. The available literature on the effects of air staging (secondary air location) at a constant primary air flow rate on combustion characteristics in a batch-type fixed bed combustor is limited and hence warrants further investigations. This study resolves the effect of …

Photocatalytic Reforming Of Lignocellulose: A Review, Xinyuan Xu, Lei Shi, Shu Zhang, Zhimin Ao, Jinqiang Zhang, Shaobin Wang, Hongqi Sun

Research outputs 2022 to 2026

Biomass has been considered as a promising energy resource to combat the exhaustion of fossil fuels, as it is renewable, sustainable, and clean. Photocatalytic reforming is a novel technology to utilize solar energy for upgrading biomass in relatively mild conditions. This process efficiently reforms and recasts biomass into hydrogen and/or valuable chemicals. To date, lignocellulose, including cellulose, hemicellulose and lignin, has attracted extensive studies in facile photocatalytic valorisation. This review summarizes and analyzes the most recent research advances on photoreforming of lignocellulose to provide insights for future research, with a particular emphasis on the reformation of lignin because of its …

Comparative Study On Development Of Novel Catalytic Oxidation For Removing Emerging Contaminants, Abdul H. Asif

Theses: Doctorates and Masters

‘Wastewater treatment’ is not itself a new concept, where global water bodies have been polluted since the evolution of mankind. As a result of human activities including domestic, industrial and commercial practices, levels of water pollution through aqueous contaminants are increasing every day. Moreover, rapid industrialisation and recent human progress has given rise to a new classification of pollution, that of emerging contaminants (ECs). Further, these chemicals are highly resistant to biodegradation and are capable of travelling, where they can penetrate from one part of the world to another. Whilst traditional wastewater treatment techniques, such as adsorption, might be effective …

Application Of A Novel Green Nano Polymer For Chemical Eor Purposes In Sandstone Reservoirs: Synergetic Effects Of Different Fluid/Fluid And Rock/Fluid Interacting Mechanisms, Abbas K. Manshad, Alireza Kabipour, Erfan Mohammadian, Lei Yan, Jagar A. A., Stefan Iglauer, Alireza Keshavarz, Milad Norouzpour, Amin Azdarpour, S. Mohammad Sajadi, Siyamak Moradi

Research outputs 2022 to 2026

In this research, a novel natural-based polymer, the Aloe Vera biopolymer, is used to improve the mobility of the injected water. Unlike most synthetic chemical polymers used for chemical-enhanced oil recovery, the Aloe Vera biopolymer is environmentally friendly, thermally stable in reservoir conditions, and compatible with reservoir rock and fluids. In addition, the efficiency of the Aloe Vera biopolymer was investigated in the presence of a new synthetic nanocomposite composed of KCl-SiO2-xanthan. This chemically enhanced oil recovery method was applied on a sandstone reservoir in Southwest Iran with crude oil with an API gravity of 22°. The Aloe Vera biopolymer’s …

Conductive 3d Nano-Biohybrid Systems Based On Densified Carbon Nanotube Forests And Living Cells, Roya Bagheri, Alicia K. Ball, Masoud Kasraie, Aparna Chandra, Xinqian Chen, Ibrahim Miskioglu, Zhiying Shan, Parisa Pour Shahid Saeed Abadi

Michigan Tech Publications

Conductive biohybrid cell-material systems have applications in bioelectronics and biorobotics. To date, conductive scaffolds are limited to those with low electrical conductivity or 2D sheets. Here, 3D biohybrid conductive systems are developed using fibroblasts or cardiomyocytes integrated with carbon nanotube (CNT) forests that are densified due to interactions with a gelatin coating. CNT forest scaffolds with a height range of 120–240 µm and an average electrical conductivity of 0.6 S/cm are developed and shown to be cytocompatible as evidenced from greater than 89% viability measured by live-dead assay on both cells on day 1. The cells spread on top and …

Direct Recycling Of Lithium-Ion Battery Materials Using Physical Separation Methods., Tinuade Ololade Folayan

Dissertations, Master's Theses and Master's Reports

The increased demand for Lithium-ion batteries for Electric vehicles has influenced worldwide interest in the research and development of methods for recycling end-of-life Lithium-ion batteries. Direct recycling method has gained more attention in recent times as a method that is low-cost with the ability to recover all Lithium-ion battery materials without changing the chemical and structural properties of the recycled materials.

A lithium-ion battery contains a complex mixture of materials with significantly different physical properties. This work develops physical separation techniques as Direct recycling methods to recycle individual battery components without damaging the functional integrity of the recycled materials. In …

Solid-State Shear Pulverization: A Comprehensive Study On Polymer Processing Technology From A Systematic Innovation Perspective, Tyler A. Will

Master’s Theses

Solid-state shear pulverization (SSSP) is a continuous and scalable processing technique that imposes mechanochemical changes in polymer-based materials. It has been shown to impart beneficial properties onto homopolymers or create copolymers and composites through continuous fragmentation and fusion. The unique technology employs cold temperature to keep the polymer in the solid state. This thesis investigates industrial polymer processing in the context of real-world applications. This thesis analyzes SSSP using an organized methodology called systematic innovation (SI). SI facilitates problem solving by assisting engineers in conducting root cause analysis around a material and studying the physical setup of the equipment.

This …

Temperature-Dependent Diffusion In Block Copolymer Organogels, Ridwana Bashar

Master’s Theses

Organogels are often considered for transport-based applications such as transdermal drug delivery vehicles and gel actuators due to their unique properties. Recent consideration of styrenic block copolymer based organogels’ application in transdermal drug delivery requires an extensive investigation of drug diffusion behavior through these gels to assess their applicability. Temperature is a major influencing parameter on diffusion. The goal of this research is to better understand the impact of temperature on diffusion in styrenic triblock copolymer organogels. To accomplish this goal, we focused on three specific objectives: (i) accurately measure the diffusivities of a solute – AOT reverse micelles – …

Running Shoe Pedometer, Benjamin Kasper

Williams Honors College, Honors Research Projects

Running shoe pedometer aims to solve the issue of worn out running shoes. It can be difficult to know just how many miles you have run in your shoes and when a new pair is needed. Running in old shoes and worn out shoes is heavily linked to injury. My proposed project is a device that is powered by the compressive forces on the shoes soles that counts the number of steps the wearer takes using a microcontroller. Then, when the shoe reaches milestone that indicate it has been used 75% 90% and 100% of its expected life, it will …

Enhancing Control Room Operator Decision Making: An Application Of Dynamic Influence Diagrams In Formaldehyde Manufacturing, Joseph Mietkiewicz, Anders L. Madsen

Articles

Intoday’s rapidly evolving industrial landscape, control room operators must grapple with an ever-growing array of tasks and respon sibilities. One major challenge facing these operators is the potential for task overload, which can lead to decision fatigue and increased reliance on cognitive biases. To address this issue, we propose the use of dynamic influence diagrams (DID) as the core of our decision support system. By monitoring the process over time and identifying anomalies, DIDs can recommend the most effective course of action based on a probabilistic assessment of future outcomes. Instead of letting the operator choose or search for the …

Development, Validation And Implementation Of Multiple Radioactive Particle Tracking Technique, Mehul S. Vesvikar, Thaar M. Aljuwaya, Mahmoud M. Taha, Muthanna H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

Computer Automated Radioactive Particle Tracking (CARPT) technique has been successfully utilized to measure the velocity profiles and mixing parameters in different multiphase flow systems where a single radioactive tracer is used to track the tagged phase. However, many industrial processes use a wide range of particles with different physical properties where solid particles could vary in size, shape and density. For application in such systems, the capability of current single tracer CARPT can be advanced to track more than one particle simultaneously. Tracking multiple particles will thus enable to track the motion of particles of different size shape and density, …

3d-Printed Boron Nitride Catalytic Monoliths For Oxidative Dehydrogenation Of Propane, Theodore Agbi, Wei Shang Lo, Khaled Baamran, Taekyung Ryu, Christine Cheung, Fateme Rezaei, Ive Hermans

Chemical and Biochemical Engineering Faculty Research & Creative Works

Boron-containing materials are efficient catalysts for the oxidative dehydrogenation of propane to propylene, proceeding via radical intermediates. The radical mechanism is initiated by the solid surface and propagated in the gas phase. It has been hypothesized that the propylene selectivity could be increased by enhancing the gas-phase contributions by favoring the formation of iso- over n-propyl radical intermediates. Indeed, whereas n-propyl radicals can be converted to both propylene and ethylene, iso-propyl radicals yield exclusively propylene. In this contribution, we explore 3D printing to structure the hexagonal boron nitride (hBN) heterogeneous catalyst with high void space. 3D-printed hBN monoliths were found …

Reactive Oxygen Species (Ros)-Responsive Size-Reducible Nanoassemblies For Deeper Atherosclerotic Plaque Penetration And Enhanced Macrophage-Targeted Drug Delivery, Jianhua He, Wenli Zhang, Xiaoju Zhou, Fengfei Xu, Jiahui Zou, Qiqi Zhang, Yi Zhao, Hongliang He, Hu Yang, Jianping Liu

Chemical and Biochemical Engineering Faculty Research & Creative Works

Nanoparticle-Based therapeutics represent potential strategies for treating atherosclerosis; however, the complex plaque microenvironment poses a barrier for nanoparticles to target the dysfunctional cells. Here, we report reactive oxygen species (ROS)-responsive and size-reducible nano assemblies, formed by multivalent host-guest interactions between β-cyclodextrins (β-CD)-anchored discoidal recombinant high-density lipoprotein (NP3ST) and hyaluronic acid-ferrocene (HA-Fc) conjugates. the HA-Fc/NP3ST nano assemblies have extended blood circulation time, specifically accumulate in atherosclerotic plaque mediated by the HA receptors CD44 highly expressed in injured endothelium, rapidly disassemble in response to excess ROS in the intimal and release smaller NP3ST, allowing for further plaque penetration, macrophage-targeted cholesterol efflux and …

Hygroscopic Tandem Differential Mobility Analyzer (Htdma) Design And Testing For Aerosol Hygroscopic Behavior Studies, Ziheng Zeng

Honors Theses

Most particles in the atmosphere take up water when exposed to increasing relative humidity (RH), and this behavior is described and quantized by a hygroscopicity parameter, kappa. Hygroscopic Tandem Differential Mobility Analysis (HTDMA) can be used to measure the physicochemical properties of aerosol particles and study phenomena that lead to size changes in submicron aerosol particles. Specifically, HTDMA measures how aerosol particles of different initial dry sizes grow or shrink when exposed to changing RH. HTDMA uses two differential mobility analyzers (DMAs) and a humidification system to make these measurements. One DMA selects a narrow size range of dry aerosol …

Development Of A Solution Synthesis Of Poly(Sebacic Anhydride) With The Activating Agent 4-Toluenesulfonyl Chloride: Understanding The Effect Of Different Bases On The Reaction Products, Patricia Poley

Honors Theses

The overall goal of this honors thesis was to develop a solution synthesis of Poly(Sebacic Anhydride) with the activating agent 4-toluenesulfonyl chloride and understand the effects of varying temperature, bases, and the addition order of reagents on the reaction.

Polyanhydrides are a class of hydrophobic, degradable polymers used in controlled drug delivery for 30 years. They are synthesized through three general methods: melt polycondensation, solution polycondensation, and ring-opening polymerization. Of these three methods, solution polycondensation typically results in products with lower molecular weight. Previous work in the Vogel lab identified two new ways to synthesize anhydrides using solution polycondensation reactions …

Interdependence Of Salt Concentration And Filler Particles On Crystallinity And Mechanical Behavior Of Peo-Litfsi Electrolytes For Lithium-Ion Batteries, Valeria Perez

Master's Theses

Developing composite polymer electrolytes is crucial for enhancing the safety, energy density, and performance of lithium-ion batteries. While it is widely accepted that introducing filler particles in PEO-based electrolytes can reduce crystallinity and enhance ionic conductivity, this conventional understanding applies primarily to electrolytes with high lithium salt concentrations. The hypothesis of this investigation is that the crystallinity change induced by LLZTO ceramic particles in PEO-LiTFSI electrolytes is contingent on the EO:Li molar ratio. This hypothesis is interrogated by measuring changes in crystallinity, spherulite morphology, and stiffness of composite polymer electrolytes with two different EO:Li molar ratios using differential scanning calorimetry, …

Exploring Ph Gradient Phenomena In Non-Linear Electrokinetic Microfluidic Devices, Azade Tahmasebi

Dissertations, Master's Theses and Master's Reports

Electrokinetic microfluidics is a versatile technology utilized within lab on a chip (LOC) devices for diagnostic and analytical applications; advantages include reduced resource demands, flexibility, and simplicity of use. Dielectrophoresis (DEP) is a precision nonlinear electrokinetic tool utilized within microfluidic microdevices to induce polarization and control bioparticle motions for applications that range from hemoglobin separations to cancer cell isolation and detection. Despite promising results, undesired side phenomena can occur in electrokinetic systems which impede reproducibility and accuracy. These unfavorable phenomena have not been comprehensively explored in the literature. Prior preliminary research suggests the fundamental phenomena originate from microelectrodes utilized in …

Batch And Fixed-Bed Adsorption Of Ciprofloxacin Using Magnetic Biochar From Macadamia Nutshell, Sakonsupa Damdib

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this research, the utilization of macadamia nutshell as a potential adsorbent for ciprofloxacin (CIP) removal was investigated. The distinctive features of macadamia nutshell, characterized by its lignocellulosic composition and hardness, make it suitable as a precursor for synthesizing magnetic biochar, aimed at CIP adsorption in both batch and fixed-bed column processes. The influence of temperature activation and carbonization temperature on the properties of the resulting biochar was examined. Macadamia nutshell impregnated with a 0.10 M iron nitrate solution and carbonized under a nitrogen atmosphere at 800°C (MB-BI-800) exhibited the highest micropore and mesopore volumes, with values of 0.14 and …

Verification Of Oil Recovery Mechanism Through Alteration Of Relative Permeability Curve And Analytical Measurements, Tina Tharn

Chulalongkorn University Theses and Dissertations (Chula ETD)

In the petroleum production industry, there are several methods that can be utilized to increase oil recovery. These methods are so-called Enhanced Oil Recovery (EOR). Nowadays, Low Salinity Water Flooding (LSWF) is one of the considerable of those techniques due to its cost and simplicity. However, understanding its main oil recovery mechanism is still limited. Therefore, the investigation of oil mechanism provided by LSWF would help refine its application to oilfields. In this study, the Johnson–Bossler–Naumann (JBN) approach is employed to examine relative permeability curves during LSWF in different rock formations including clean sandstone (SS), shaly-sandstone (SHS), and dolostone (DL). …

ผลของแกรฟีนควอนตัมดอทต่อการเจริญเติบโตและฤทธิ์ต้านอนุมูลอิสระของต้นถั่วเขียวและต้นอ่อนทานตะวัน, วราวุธ คงแสงชัย

Chulalongkorn University Theses and Dissertations (Chula ETD)

แกรฟีนควอนตัมดอท (Graphene Quantum Dots) จัดเป็นวัสดุนาโนที่มีคุณสมบัติเชิงแสงที่เป็นเอกลักษณ์จากผลของการกักกันเชิงควอนตัม อีกทั้งยังมีความเข้ากันได้กับเซลล์ของสิ่งมีชีวิตค่อนข้างสูง รวมทั้งความเป็นพิษต่อเซลล์ของสิ่งมีชีวิตที่ต่ำ สำหรับงานวิจัยนี้เป็นการศึกษาผลของการเติม GQDs ที่มีต่อการเจริญเติบโตและฤทธิ์ต้านอนุมูลอิสระ ซึ่งเมล็ดต้นกล้าที่ใช้ในการศึกษา คือ เมล็ดถั่วเขียวและเมล็ดต้นอ่อนทานตะวัน โดยจะติดตามการเจริญเติบโตในลักษณะเทคนิคต่างๆของการเติม GQDs 3 เทคนิควิธีการ ได้แก่ 1.) การแช่เมล็ดด้วย GQDs ที่ความเข้มข้นต่างๆ 2.) การเติม GQDs ให้กับต้นกล้าในลักษณะการใส่ปุ๋ยที่ความเข้มข้นต่างๆ และ 3.) การกระทำทั้งเทคนิควิธีการที่ 1 และ 2 ร่วมกันในช่วงความเข้มข้น 0 - 0.3 mg/mL ของ GQDs พบว่าต้นกล้าถั่วเขียวที่ความเข้มข้น 0.3 mg/mL ด้วยเทคนิควิธีการเติม GQDs ให้กับต้นกล้าในลักษณะการใส่ปุ๋ยมีฤทธิ์ต้านอนุมูลอิสระมากที่สุดถึง 33.67% เมื่อเทียบกับต้นกล้า control แต่สำหรับต้นกล้าต้นอ่อนทานตะวันนั้นจะพบว่าที่ความเข้มข้น 0.3 mg/mL เทคนิควิธีร่วมกันทั้ง 2 วิธีการจะให้ฤทธิ์ต้านอนุมูลอิสระมากที่สุด 38.24% เมื่อเทียบกับต้นกล้า control

Modeling And Simulation Of A Process That Converts Ethane To Ethylene And Ethylene To Low Density Polyethylene, Ernest Bosire Mokaya

Graduate Theses, Dissertations, and Problem Reports (ETD)

Ethylene is a critical feedstock and a major building block in the petrochemical industry that is used in synthesizing important products like polyethylene, ethanol, ethylene oxide, ethylene dichloride and ethylbenzene. With increasing demand of plastics, production of ethylene and subsequently polyethylene has increased globally. This thesis conducts the modeling and simulation of an integrated process that utilizes ethane as the primary feedstock to produce ethylene and the subsequent polymerization of ethylene to low-density polyethylene (LDPE). The process combines two different processes into one integrated process: (1) conversion of ethane to ethylene and (2) conversion of ethylene to LDPE. First, a …

Synthesis Of Quasi-Freestanding Graphene Films Using Radical Species Formed In Cold Plasmas, Michael A. Mathews Jr.

Graduate Theses, Dissertations, and Problem Reports (ETD)

For over a decade, the Stinespring laboratory has investigated scalable, plasma assisted synthesis (PAS) methods for the growth of graphene films on silicon carbide (SiC). These typically utilized CF₄-based inductively coupled plasma (ICP) with reactive ion etching (RIE) to selectively etch silicon from the SiC lattice. This yielded a halogenated carbon-rich surface layer which was then annealed to produce the graphene layers. The thickness of the films was controlled by the plasma parameters, and overall, the process was readily scalable to the diameter of the SiC wafer.

The PAS process reproducibly yielded two- to three-layer thick graphene films …