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An Open-Source, Automated Chemical Vapor Deposition System For The Production Of 2d Materials, Dale Brown Dec 2015

An Open-Source, Automated Chemical Vapor Deposition System For The Production Of 2d Materials, Dale Brown

Boise State University Theses and Dissertations

While interest in two-dimensional materials has exploded in recent years, the high cost of chemical vapor deposition (CVD) systems can act as a barrier to entry for some researchers interested in studying these materials. This thesis presents an open-source design for an automated CVD that can be built for a fraction of the cost of similarly capable commercial systems and that can easily be customized and expanded.With a CVD built as described,growth of high quality graphene and graphene foam is demonstrated.These results highlight the flexibility of the open-source design in producing a variety of nanomaterials, which are at the forefront …


Investigation Of Electrical And Magneto Transport Properties Of Reduced Graphene Oxide Thin Films, Ariful Haque Jul 2015

Investigation Of Electrical And Magneto Transport Properties Of Reduced Graphene Oxide Thin Films, Ariful Haque

MSU Graduate Theses

Large area uniform thin films of reduced graphene oxide (RGO) was synthesized by pulsed laser deposition (PLD) technique. A number of structural properties including the defect density, average size of sp2 clusters, and degree of reduction were investigated by Raman spectroscopy and X-ray diffraction (XRD) analysis. The temperature dependent (5K - 350K) four terminal electrical transport property measurement confirms variable range hopping and thermally activated transport mechanism of the charge carriers at low (5K - 210K) and high temperature (210K - 350K) regions, respectively. The calculated localization length, density of states (DOS) near Fermi level (EF), hopping energy, and Arrhenius …


Processing And Characterization Of Graphene And Graphene On Silicon, Cheng Peng May 2015

Processing And Characterization Of Graphene And Graphene On Silicon, Cheng Peng

Theses

Graphene has become a promising material for applications in many areas including electronic devices, batteries and space crafts. Although it has a bright future, the commercial production of graphene has not yet been realized. In this thesis, an overview of the properties and applications of graphene is presented. The early research of preparing graphene and its composites is summarized, which gives the basis to synthesize graphene and improve the process. In this study, graphene oxide (GO) and graphene have been successfully made using graphite; graphene layer has been coated on the surface of a silicon wafer. The resulting specimens are …


Simulation Of Electronic And Optical Properties Of Graphene, Biao Leng May 2015

Simulation Of Electronic And Optical Properties Of Graphene, Biao Leng

Theses

Graphene is a recently discovered two-dimensional crystal. Due to its excellent electronic properties, transport properties, optical properties, and many other features, it has tremendous potential for applications in many areas. This thesis discusses the structure and properties of graphene using several different models of graphene and carries out detailed theoretical studies and calculations of its electronic and optical properties. Using two modules of Materials Studio, CASTAP and Doml3, four graphene models have been constructed. Their electronic and optical properties have also been calculated via these two modules. By comparing the results of calculations with experimental results and the literature, the …


Thermal Properties Of Graphene, Vishal Vijay Nakhate May 2015

Thermal Properties Of Graphene, Vishal Vijay Nakhate

Theses

The two-dimensional (2D) monolayer structure of carbon atoms were initially considered as unstable. The 2D materials have recently been discovered and many researchers have started analyzing these materials. Graphene, a two-dimensional allotrope of graphite with sp2 bonded carbon atoms, is arranged in honeycomb structure. Graphene has excellent thermal conductivity and can be considered as a potential material for applications in the electronics industry where heating of materials is a serious concern.

In this study, thermal properties of p and n doped graphene nanosheets and nanoribbons are studied as function of percentage composition of the dopants and the direction of dissipation …


Large-Scale Graphene Film Deposition For Monolithic Device Fabrication, Khaled Al-Shurman May 2015

Large-Scale Graphene Film Deposition For Monolithic Device Fabrication, Khaled Al-Shurman

Graduate Theses and Dissertations

Since 1958, the concept of integrated circuit (IC) has achieved great technological developments and helped in shrinking electronic devices. Nowadays, an IC consists of more than a million of compacted transistors.

The majority of current ICs use silicon as a semiconductor material. According to Moore's law, the number of transistors built-in on a microchip can be double every two years. However, silicon device manufacturing reaches its physical limits. To explain, there is a new trend to shrinking circuitry to seven nanometers where a lot of unknown quantum effects such as tunneling effect can not be controlled. Hence, there is an …


Electronic, Optical, Mechanical And Thermoelectric Properties Of Graphene, Sarang Vilas Muley Jan 2015

Electronic, Optical, Mechanical And Thermoelectric Properties Of Graphene, Sarang Vilas Muley

Dissertations

Graphene, a two-dimensional allotrope of graphite with sp2 bonded carbon atoms, is arranged in honeycomb structure. Its quasi one-dimensional form is graphene nanoribbon (GNR). Graphene related materials have been found to display excellent electronic, chemical, mechanical properties along with uniquely high thermal conductivity, electrical conductivity and high optical transparency. With excellent electrical characteristics such as high carrier transport properties, quantum Hall effect at room temperature and unusual magnetic properties, graphene has applications in optoelectronic devices.

Electronically, graphene is a zero bandgap semiconductor making it essential to tailor its structure for obtaining specific band structure. Narrow GNRs are known to …


Molecular Modeling Of Epon 862-Detda / Carbon Composites, Cameron Hadden Jan 2015

Molecular Modeling Of Epon 862-Detda / Carbon Composites, Cameron Hadden

Dissertations, Master's Theses and Master's Reports - Open

The thermoset epoxy resin EPON 862, coupled with the DETDA hardening agent, are utilized as the polymer matrix component in many graphite (carbon fiber) composites. Because it is difficult to experimentally characterize the interfacial region, computational molecular modeling is a necessary tool for understanding the influence of the interfacial molecular structure on bulk-level material properties. The purpose of this research is to investigate the many possible variables that may influence the interfacial structure and the effect they will have on the mechanical behavior of the bulk level composite. Molecular models are established for EPON 862-DETDA polymer in the presence of …


Carbon Based Nano-Composite Materials For Energy Storage Applications, Gerardo Rodriguez Melo Jan 2015

Carbon Based Nano-Composite Materials For Energy Storage Applications, Gerardo Rodriguez Melo

Open Access Theses & Dissertations

Energy storage systems and devices are an integral part of advanced electronic technology. Electronic technology is ever-advancing, but in order to do so, it must be supported by all its systems. The energy storage system is one key system that may dictate the performance and limitation of such electronics. Thus, research emphasis on energy storage devices has been on improving the performance of energy storage devices, such as: improved energy and power density, increased stability and cycle life, as well as reduced costs. Lithium-ion-batteries, and supercapacitors offer the potential to meet energy storage demands and to be improved further upon. …


Graphene Based Metamaterials For Terahertz Cloaking And Subwavelength Imaging, Seyedali Forouzmand Jan 2015

Graphene Based Metamaterials For Terahertz Cloaking And Subwavelength Imaging, Seyedali Forouzmand

Electronic Theses and Dissertations

Graphene is a two-dimensional carbon crystal that became one of the most controversial topics of research in the last few years. The intense interest in graphene stems from recent demonstrations of their potentially revolutionary electromagnetic applications – including negative refraction, subdiffraction imaging, and even invisibility – which have suggested a wide range of new devices for communications, sensing, and biomedicine. In addition, it has been shown that graphene is amenable to unique patterning schemes such as cutting, bending, folding, and fusion that are predicted to lead to interesting properties. A recent proposed application of graphene is in engineering the scattering …


The Synthesis Of Solid Supported Palladium Nanoparticles: Effective Catalysts For Batch And Continuous Cross Coupling Reactions, Kendra W. Brinkley Jan 2015

The Synthesis Of Solid Supported Palladium Nanoparticles: Effective Catalysts For Batch And Continuous Cross Coupling Reactions, Kendra W. Brinkley

Theses and Dissertations

Catalysis is one of the pillars of the chemical industry. While the use of catalyst is typically recognized in the automobile industry, their impact is more widespread as; catalysts are used in the synthesis of 80% of the US commercial chemicals. Despite the improved selectivity provided by catalyst, process inefficiencies still threaten the sustainability of a number of synthesis methods, especially in the pharmaceutical industry. Recyclable solid supported catalysts offer a unique opportunity to address these inefficiencies. Such systems coupled with continuous synthesis techniques, have the potential to significantly reduce the waste to desired product ratio (E-factor) of the production …


Evaporative Vapor Deposition For Depositing 2d Materials, Kevin Gleason Jan 2015

Evaporative Vapor Deposition For Depositing 2d Materials, Kevin Gleason

Electronic Theses and Dissertations

The development of a new deposition technique called evaporative vapor deposition (EVD) is reported, allowing deposition and formation of atomically-thin, large area materials on arbitrary substrates. This work focuses on the highly popular monolayer material – graphene oxide (GO). A droplet of a GO solution is formed on a heated polymer substrate, and maintained at steady-state evaporation (all droplet parameters are held constant over time). The polymer substrate is laser patterned to control the droplet's contact line dynamics and the droplet's contact angle is maintained using a computer controlled syringe pump. A room temperature silicon wafer is translated through the …


Nano And Nanostructured Materials For Optical Applications, Panit Chantharasupawong Jan 2015

Nano And Nanostructured Materials For Optical Applications, Panit Chantharasupawong

Electronic Theses and Dissertations

Nano and nanostructured materials offer unique physical and chemical properties that differ considerably from their bulk counterparts. For decades, due to their fascinating properties, they have been extensively explored and found to be beneficial in numerous applications. These materials are key components in many cutting-edge optic and photonic technologies, including photovoltaics, waveguides and sensors. In this dissertation, the uses of nano and nanostructured materials for optical applications are investigated in the context of optical limiting, three dimensional displays, and optical sensing. Nanomaterials with nonlinear optical responses are promising candidates for self-activating optical limiters. In the first part of this study, …


Carbon 1d/2d Nanoelectronics : Integration And Device Applications, Zhaoying Hu Jan 2015

Carbon 1d/2d Nanoelectronics : Integration And Device Applications, Zhaoying Hu

Legacy Theses & Dissertations (2009 - 2024)

Graphene is a one-atom thick planar monolayer of sp2-bonded carbon atoms organized in a hexagonal crystal lattice. A single walled carbon nanotube (CNT) can be thought of as a graphene sheet rolled up into a seamless hollow cylinder with extremely high length-to-diameter ratio. Their ultra-thin body, large surface area, and exceptional electronic, optical and mechanical properties make these low-dimensional carbon materials ideal candidates for electronic applications. However, adopting low-dimensional carbon materials into semiconductor industry faces significant material and integration challenges. There is an urgent need for research at fundamental and applicative levels to find a roadmap for carbon nanomaterial to …


Hexagonal Boron Nitride : Ubiquitous Layered Dielectric For Two-Dimensional Electronics, Nikhil Jain Jan 2015

Hexagonal Boron Nitride : Ubiquitous Layered Dielectric For Two-Dimensional Electronics, Nikhil Jain

Legacy Theses & Dissertations (2009 - 2024)

Hexagonal boron nitride (h-BN), a layer-structured dielectric with very similar crystalline lattice to that of graphene, has been studied as a ubiquitous dielectric for two-dimensional electronics. While 2D materials may lead to future platform for electronics, traditional thin-film dielectrics (e.g., various oxides) make highly invasive interface with graphene. Multiple key roles of h-BN in graphene electronics are explored in this thesis. 2D graphene/h-BN heterostructures are designed and implemented in diverse configurations in which h-BN is evaluated as a supporting substrate, a gate dielectric, a passivation layer, or an interposing barrier in “3D graphene” superlattice. First, CVD-grown graphene on h-BN substrate …


Nano-Materials For Microwave And Terahertz Applications, Joshua Myers Jan 2015

Nano-Materials For Microwave And Terahertz Applications, Joshua Myers

Browse all Theses and Dissertations

In this age of digital electronics the quest for faster computational devices and high speed communications have driven a need for new materials that are capable of fulfilling these goals. In both areas the need for a thinner channel in transistors, faster carrier transport characteristics, and better magnetic materials dominate the direction of research. Recently 2D materials have been realized. These single layer atomic thick materials show potential in having extremely high carrier transport velocities at room temperature and, due to their natural 2D structure, are the thinnest material possible in nature. On the other hand spin-spray ferrites have showed …


Hybrid Nano-Structure For Enhanced Energy Storage Devices, Mohammad Arif Ishtiaque Shuvo Jan 2015

Hybrid Nano-Structure For Enhanced Energy Storage Devices, Mohammad Arif Ishtiaque Shuvo

Open Access Theses & Dissertations

The goal of this research is to develop electrode materials using various nano-structure hybrids for improved energy storage devices. Enhancing the performance of energy storage device has been gaining tremendous attention since it holds the key solution to advance renewable energy usage thus reduce the consumption of fossil fuels. The application of energy storage devices such as super-capacitor and Li-ion-battery has seen significant growth; however, it is still limited mainly by charge/discharge rate and energy density. One of the solutions is to use nano-structure materials, which offer higher power at high energy density and improved stability during the charge discharge …


Graphene Based Heterojunctions For Nano-Electronic And Sensing Applications, Md A. Uddin Jan 2015

Graphene Based Heterojunctions For Nano-Electronic And Sensing Applications, Md A. Uddin

Theses and Dissertations

Graphene, an atomically thin and semi-metallic two dimensional material, has been extensively researched over the past decade due to its superior intrinsic carrier velocity, electrical and chemically tunable work function, ability to form layered heterostructure with other materials, and relevant potential applications in electronics, sensing, optoelectronics, energy storage, etc. However, the confinement of charge carriers within one atomic layer results in an electrical transport that is extremely sensitive to the surrounding environment, which is beneficial for sensing applications, but at times unfavorable for electronic applications due to scattering from extrinsic impurities. In addition, due to its rather delicate structure, engineering …


Near Total Resonant Light Absorption In A Graphene Monolayer At Multiple Tunable Wavelengths With Multilayer Structures, Iman Zand Jan 2015

Near Total Resonant Light Absorption In A Graphene Monolayer At Multiple Tunable Wavelengths With Multilayer Structures, Iman Zand

LSU Master's Theses

Graphene could be potentially important for a broad range of photonic and optoelectronic applications. For such graphene-based applications it is critical to enhance the absorption of light in graphene monolayers in order to achieve near total absorption. Several structures have been proposed to enhance light absorption in graphene at visible and infrared wavelengths such as one-dimensional Fabry-Perot cavity structures, and photonic crystal slabs. Fabry-Perot cavity structures, which employ periodic Bragg mirrors, can lead to near total light absorption on resonance. However, such structures cannot achieve near complete absorption in graphene at multiple closely-spaced tunable wavelengths, which is potentially important for …