Single-Step, Atmospheric Pressure Chemical Vapor Deposition Of Methylammonium Bismuth Iodide Thin Films, 2017 Washington University in St. Louis
Single-Step, Atmospheric Pressure Chemical Vapor Deposition Of Methylammonium Bismuth Iodide Thin Films, Xiao Chen
Engineering and Applied Science Theses & Dissertations
Lead halide perovskites (CH3NH3PbI3 and its variants) are promising solar cell absorber materials. Though the reported power conversion efficiencies of lead halide perovskite solar cells (up to 21%) are competitive with commercial silicon solar cells, lead toxicity in these perovskites present a challenge to further scale-up and eventual commercialization. Recently, bismuth (Bi3+) based organic halide perovskite has drawn attention as a substitution for lead-free perovskites, since it is a non-toxic 6p-block element, isoelectronic with Pb2+. Methylammonium bismuth iodide ((CH3NH3)3Bi2I9) is reported for its non-toxic constituents ...
Atomistic Simulations Of Novel Nanoscale Semiconductor Devices: Resistance Switches And Two-Dimensional Transistors, 2017 Texas A & M University - College Station
Atomistic Simulations Of Novel Nanoscale Semiconductor Devices: Resistance Switches And Two-Dimensional Transistors, Joseph P. Anderson, Mahbubul Islam, David Guzman, Alejandro Strachan
The Summer Undergraduate Research Fellowship (SURF) Symposium
As transistors get smaller, we are achieving record levels of memory density. However, there is a limit to how small transistors can be made before their functionality breaks down. Thus alternatives to traditional transistor technology are needed. The two such technologies we examined are: resistance switching devices, which reversibly grow metal filaments through a dielectric, and two-dimensional transistors, which are capable of breaking through the scalability limit of traditional transistors. In order to design resistance switching devices which create filaments with some level of consistency, the dynamics of the filament formation need to be explored. Herein we model this process ...
Improving Methods Of Doping On Black Phosphorus, 2017 Electrocal and Computer Engineering
Improving Methods Of Doping On Black Phosphorus, Yuqin Duan, Adam Charnas, Jingkai Qin, Peide Ye
The Summer Undergraduate Research Fellowship (SURF) Symposium
Black phosphorus (BP) is a 2D semiconducting material with high carrier mobility. It is usually p-type due to oxidation states near its valence band. Although achieved through other growth methods, n-type doping has not yet been accomplished through the modern chemical vapor transport (CVT) growth method. To address this issue, small amounts of tellurium were added to Red Phosphorus to act as a dopant during the CVT growth process in addition to tin(Sn) and tin(IV) iodide, which facilitate growth. The chemicals are heated up to 600°C and precisely cooled in a 21-hour process, during which BP crystals ...
Fabrication And Characterization Of Hybrid Nanocomposites By Matrix Assisted Pulsed Laser Evaporation, 2017 The University of Western Ontario
Fabrication And Characterization Of Hybrid Nanocomposites By Matrix Assisted Pulsed Laser Evaporation, Songlin Yang
Electronic Thesis and Dissertation Repository
Different methods have been applied to deposit hybrid nanocomposites which can be applied in various fields due to their light weight and multifunctional properties. Here, matrix assisted pulsed laser evaporation (MAPLE) equipment with 532 nm Nd:YAG laser is applied to fabricate three types of hybrid nanocomposites on different substrates.
Chemical synthesized FeCo nanoparticles were deposited on graphene sheets by MAPLE technique (laser fluence: 300 mJ/cm2). The effects of deposition time (t) on particle amount, shape and size have been investigated. Yttrium barium copper oxide (YBCO) materials are one type of high-temperature superconductive materials and could be applied ...
Electrical Characterization Of Irradiated Semiconducting Amorphous Hydrogenated Boron Carbide, 2017 University of Nebraska-Lincoln
Electrical Characterization Of Irradiated Semiconducting Amorphous Hydrogenated Boron Carbide, George Glen Peterson
Mechanical (and Materials) Engineering -- Dissertations, Theses, and Student Research
Semiconducting amorphous partially dehydrogenated boron carbide has been explored as a neutron voltaic for operation in radiation harsh environments, such as on deep space satellites/probes. A neutron voltaic device could also be used as a solid state neutron radiation detector to provide immediate alerts for radiation workers/students, as opposed to the passive dosimetry badges utilized today. Understanding how the irradiation environment effects the electrical properties of semiconducting amorphous partially dehydrogenated boron carbide is important to predicting the stability of these devices in operation. p-n heterojunction diodes were formed from the synthesis of semiconducting amorphous partially dehydrogenated boron carbide ...
Are Solar Panels A Viable Power Source For A Green Energy Vehicle?, 2017 Linfield College
Are Solar Panels A Viable Power Source For A Green Energy Vehicle?, Mason C. Adams
A solar cell powered go-kart has been built and tested. The result shows using solar energy alone cannot meet the requirement of running a regular passenger car. This is due to the limited surface area of the passenger car. This thesis also discusses the operating principles of solar panels, the physics of P type and N type semiconductors, and the formation of the PN junction, as well as the solar current. Modifications of an existing go-kart are described in detail in this thesis. Suggestions for making green vehicles are discussed as well.
Operating Temperature Of A Solar Thermal Stirling Engine, 2017 Linfield College
Operating Temperature Of A Solar Thermal Stirling Engine, Spencer Beck
This paper explores the relationship between the operating temperature and electricity production of a simple heat engine. A Stirling engine was designed and constructed which runs on solar thermal energy collected by a Fresnel lens. The surface area of the solar collector was varied. This manipulated the operating temperature of the Stirling engine in order to measure power output. The mechanical energy from the engine was converted to electricity using a DC motor running in reverse, acting like a generator, in conjunction with an Arduino for data collection. Although adjustments must be made in order to improve the efficiency of ...
Ferroelectric-Semiconductor Systems For New Generation Of Solar Cells, 2017 University of New Orleans, New Orleans
Ferroelectric-Semiconductor Systems For New Generation Of Solar Cells, Rahmatollah Eskandari
University of New Orleans Theses and Dissertations
This dissertation includes two parts. In the first part the study is focused on the fabrication of multifunctional thin films for photovoltaic applications. There is no doubt about the importance of transforming world reliance from traditional energy resources, mainly fossil fuel, into renewable energies. Photovoltaic section still owns very small portion of the production, despite its fast growth and vast research investments. New methods and concepts are proposed in order to improve the efficiency of traditional solar cells or introduce new platforms. Recently, ferroelectric photovoltaics have gained interest among researchers. First objective in application of ferroelectric material is to utilize ...
Understanding Photovoltaic Properties Of Pbs Quantum Dot Solids Via Solution Contacting, 2017 Portland State University
Understanding Photovoltaic Properties Of Pbs Quantum Dot Solids Via Solution Contacting, Vitalii Dereviankin, Erik Johansson
Student Research Symposium
Photovoltaic (PV) devices based on PbS quantum dot (QD) solids demonstrate high photontoelectron conversion yields. However, record power conversion efficiency remain low, in part due to small photovoltages, which in turn are affected by both bulk and interfacial defects. Their relative impacts on limiting the photovoltaic performance of QD solids are not known. Interfacial defects can be formed when contacting a semiconductor and may dominate the semiconductor/metal or metaloxide junction properties. The objective of this study is to explore whether electrochemical contacting using liquid electrolytes provides means of contacting QD solids without introducing interfacial defects. We have initially focused ...
Investigating The Classical And Non-Classical Mechanical Properties Of Gan Nanowires, 2017 University of New Mexico
Investigating The Classical And Non-Classical Mechanical Properties Of Gan Nanowires, Mohammad Reza Zamani Kouhpanji
Electrical and Computer Engineering ETDs
Study and prediction of classical and non-classical mechanical properties of GaN is crucial due to the potential application of GaN nanowires (NWs) in piezoelectric, probe-based nanometrology, and nanolithography areas. GaN is mainly grown on sapphire substrates whose lattice constant and thermal expansion coefficient are significantly different from GaN. These discrepancies cause mechanical defects and high residual stresses and strains in GaN, which reduce its quantum efficiency.
Specifically, for nanoscale applications, the mechanical properties of materials differ significantly compared to the bulk properties due to size-effects. Therefore, it is essential to investigate the mechanical properties of GaN NWs using the non-classical ...
A Novel Technique For Designing High Power Semiconductor Optical Amplifier (Soa)-Based Tunable Fiber Compound-Ring Lasers Using Low Power Optical Components, 2017 CUNY New York City College of Technology
A Novel Technique For Designing High Power Semiconductor Optical Amplifier (Soa)-Based Tunable Fiber Compound-Ring Lasers Using Low Power Optical Components, Muhammad A. Ummy, Simeon Bikorimana, Roger Dorsinville
Publications and Research
A simple, stable and inexpensive dual-output port widely tunable semiconductor optical amplifier (SOA)-based fiber compound-ring laser structure is demonstrated. This unique nested ring cavity enables high optical power to split into different branches where amplification and wavelength selection are achieved by using low-power SOAs and a tunable filter. Furthermore, two Sagnac loop mirrors, which are spliced at the two ends of the compound-ring cavity not only serve as variable reflectors but also channel the optical energy back to the same port without using any high optical power combiner. We propose and discuss how the demonstrated fiber compound-ring laser structure ...
Compositionally Graded Indium Gallium Nitride Solar Cells, 2017 University of Arkansas, Fayetteville
Compositionally Graded Indium Gallium Nitride Solar Cells, Christopher Matthews
Electrical Engineering Undergraduate Honors Theses
For the past several decades, methods to harvest solar energy have been investigated intensively. A majority of the work done in this field has been on solar cells made with silicon – the most mature semiconductor material. Recent developments in material fabrication and processing techniques have enabled other semiconductor materials to attract practical interest and research effort as well. Indium gallium nitride (InGaN) is one such material. The material properties of InGaN indicate that solar cells made with it have the potential to achieve much higher power density than a standard silicon solar cell. High power density InGaN solar cells could ...
Infrared Energy Conversion In Plasmonic Fields At Two-Dimensional Semiconductors, 2017 University of Arkansas, Fayetteville
Infrared Energy Conversion In Plasmonic Fields At Two-Dimensional Semiconductors, Gregory Thomas Forcherio
Theses and Dissertations
Conversion of infrared energy within plasmonic fields at two-dimensional, semiconductive transition metal dichalcogenides (TMD) through plasmonic hot electron transport and nonlinear frequency mixing has important implications in next-generation optoelectronics. Drude-Lorentz theory and approximate discrete dipole (DDA) solutions to Maxwell’s equations guided metal nanoantenna design towards strong infrared localized surface plasmon resonance (LSPR). Excitation and damping dynamics of LSPR in heterostructures of noble metal nanoantennas and molybdenum- or tungsten-disulfide (MoS2; WS2) monolayers were examined by parallel synthesis of (i) DDA electrodynamic simulations and (ii) near-field electron energy loss (EELS) and far-field optical transmission UV-vis spectroscopic measurements. Susceptibility to second-order nonlinear ...
Fabrication And Study Of The Structure And Magnetism Of Rare-Earth Free Nanoclusters, 2017 University of Nebraska-Lincoln
Fabrication And Study Of The Structure And Magnetism Of Rare-Earth Free Nanoclusters, Bhaskar Das
Theses, Dissertations, and Student Research: Department of Physics and Astronomy
No abstract provided.
Computational Studies Of Grain Boundary Behavior In Uranium Dioxide Nuclear Fuels, 2017 Westinghouse Electric Company LLC
Computational Studies Of Grain Boundary Behavior In Uranium Dioxide Nuclear Fuels, Eric Nelson, Lan Li (Mentor), Simon C. Middleburgh (Mentor)
Idaho Conference on Undergraduate Research
Nuclear power is responsible for the production of 380,000 Megawatts of energy worldwide, which results in over 11% of the world’s energy production [world-nuclear.org]. Pellet-cladding interactions (PCI) are a key nuclear fuel failure mechanism which presents formidable challenges to researchers due to extreme nuclear fission conditions. Although PCI interactions have been reduced due to fuel additives, understandings of PCI interactions remain elusive. We propose new approaches to increase understanding of nuclear fuel interactions; specifically, uranium dioxide and the effects of dopants. This study focuses on amorphous uranium dioxide and fission products, while benchmarking new methods with previous ...
Assessment Of Individual Photovoltaic Module Performance After 26 Years Of Field Exposure At The Telonicher Marine Lab In Trinidad, California, Jake Rada
In 1990, 192 ARCO M75 photovoltaic (PV) modules were installed as a part of the Schatz Solar Hydrogen Project at the Humboldt State University (HSU) Telonicher Marine Lab in Trinidad, California, within 150 m of the Pacific Ocean. This 9.2 kW-rated PV array was used to power the marine laboratory air compressor and an electrolyzer. Individual current-voltage (IV) curve tests were performed on each of the PV modules prior to the array’s construction in 1990 and again in 2001, 2010, and, most recently, in 2016, following decommissioning of the array. After 25.5 years of use, 188 of ...
The Effects Of Carboxylic Acids In Aluminum Anodizing, 2017 University of New Hampshire
The Effects Of Carboxylic Acids In Aluminum Anodizing, Abby E. Koczera
Honors Theses and Capstones
Hard-anodized alumina coatings were formed in sulfuric acid at low temperature and high current density in the presence of carboxylic acid additives. Citric acid, trimesic acid, mellitic acid and ethylenediaminetetraacetic acid (EDTA) were utilized in varying concentrations. The additives were chosen for their capacity to form complexes with tri-valent aluminum and hence impart chemical stability to the coatings. The coatings were sealed in boiling water, and corrosion resistance was observed in a high pH solution of potassium hydroxide. The coatings were examined using scanning electron microscopy (SEM) to assess coating thickness and pore dimensions. Thicker coatings were produced when the ...
Acenes, Heteroacenes And Analogous Molecules For Organic Photovoltaic And Field Effect Transistor Applications, 2017 University of Kentucky
Acenes, Heteroacenes And Analogous Molecules For Organic Photovoltaic And Field Effect Transistor Applications, Devin B. Granger
Theses and Dissertations--Chemistry
Polycyclic aromatic hydrocarbons composed of benzenoid rings fused in a linear fashion comprise the class of compounds known as acenes. The structures containing three to six ring fusions are brightly colored and possess band gaps and charge transport efficiencies sufficient for semiconductor applications. These molecules have been investigated throughout the past several decades to assess their optoelectronic properties. The absorption, emission and charge transport properties of this series of molecules has been studied extensively to elucidate structure-property relationships. A wide variety of analogous molecules, incorporating heterocycles in place of benzenoid rings, demonstrate similar properties to the parent compounds and have ...
The Impact Of Quantum Size Effects On Thermoelectric Performance In Semiconductor Nanostructures, 2017 University of Massachusetts - Amherst
The Impact Of Quantum Size Effects On Thermoelectric Performance In Semiconductor Nanostructures, Adithya Kommini
An increasing need for effective thermal sensors, together with dwindling energy resources, have created renewed interests in thermoelectric (TE), or solid-state, energy conversion and refrigeration using semiconductor-based nanostructures. Effective control of electron and phonon transport due to confinement, interface, and quantum effects has made nanostructures a good way to achieve more efficient thermoelectric energy conversion. This thesis studies the two well-known approaches: confinement and energy filtering, and implements improvements to achieve higher thermoelectric performance. The effect of confinement is evaluated using a 2D material with a gate and utilizing the features in the density of states. In addition to that ...
High Performance Silver Diffusive Memristors For Future Computing, 2017 University of Massachusetts Amherst
High Performance Silver Diffusive Memristors For Future Computing, Rivu Midya
Sneak path current is a significant remaining obstacle to the utilization of large crossbar arrays for non-volatile memories and other applications of memristors. A two-terminal selector device with an extremely large current-voltage nonlinearity and low leakage current could solve this problem. We present here a Ag/oxide-based threshold switching (TS) device with attractive features such as high current-voltage nonlinearity (~1010), steep turn-on slope (less than 1 mV/dec), low OFF-state leakage current (~10-14 A), fast turn ON/OFF speeds (<75/250 ns), and good endurance (>108 cycles). The feasibility of using this selector with a typical memristor has been demonstrated by physically integrating ...75/250>