Nanoscience and Nanotechnology Commons^™

Photocatalytic Degradation Of Organic Contaminants By Titania Particles Produced By Flame Spray Pyrolysis, Noah Babik

Theses and Dissertations

Advanced oxidation of organic pollutants with TiO2 photocatalysts is limited due to the wide bandgap of TiO2, 3.2 eV, which requires ultraviolet (UV) radiation. When nanosized TiO2 is modified by carbon doping, charge recombination is inhibited and the bandgap is narrowed, allowing for efficient photodegradation under visible light. Here, we propose a flame spray pyrolysis (FSP) technique to create TiO2. The facile process of FSP has been successful in preparing highly crystalline TiO2 nanoparticles. Using the same procedure to deposit TiO2 onto biochar, the photocatalyst was doped by the carbonaceous material. The morphology, crystalline and electronic structure of the FSP …

Monolithically Integrated Microscale Pressure Sensor On An Optical Fiber Tip [U.S. Patent Us11326970b2], Jeremiah C. Williams, Hengky Chandrahalim

Faculty Publications

A passive microscopic Fabry-Pérot Interferometer (FPI) pressure sensor includes an optical fiber and a three-dimensional microscopic optical enclosure. The three-dimensional microscopic optical enclosure includes tubular side walls having lateral pleated corrugations and attached to a cleaved tip of the optical fiber to receive a light signal. An optically reflecting end wall is distally engaged to the tubular side walls to enclose a trapped quantity of gas that longitudinally positions the optically reflecting end wall in relation to ambient air pressure, changing a distance traveled by a light signal reflected back through the optical fiber.

Hinged Temperature-Immune Self-Referencing Fabry–Pérot Cavity Sensors [Us Patent Us11320596b2], Jeremiah C. Williams, Hengky Chandrahalim

Faculty Publications

A passive microscopic Fabry-Pérot Interferometer (FPI) sensor includes a three-dimensional microscopic optical structure formed on a cleaved tip of the optical fighter using a two-photon polymerization process on a photosensitive polymer by a three-dimensional micromachining device. The three-dimensional microscopic optical structure having a hinged optical layer pivotally connected to a distal portion of a suspended structure. A reflective layer is deposited on a mirror surface of the hinged optical layer while in an open position. The hinged optical layer is subsequently positioned in the closed position to align the mirror surface to at least partially reflect a light signal back …

A Versatile Python Package For Simulating Dna Nanostructures With Oxdna, Kira Threlfall

Computer Science and Computer Engineering Undergraduate Honors Theses

The ability to synthesize custom DNA molecules has led to the feasibility of DNA nanotechnology. Synthesis is time-consuming and expensive, so simulations of proposed DNA designs are necessary. Open-source simulators, such as oxDNA, are available but often difficult to configure and interface with. Packages such as oxdna-tile-binding pro- vide an interface for oxDNA which allows for the ability to create scripts that automate the configuration process. This project works to improve the scripts in oxdna-tile-binding to improve integration with job scheduling systems commonly used in high-performance computing environments, improve ease-of-use and consistency within the scripts compos- ing oxdna-tile-binding, and move …

Atomic Force Microscopy Based Dna Sensing And Manipulation, Matthew Shubert

Mechanical Engineering Undergraduate Honors Theses

Sequencing DNA provides a positive impact for the biomedical community by understanding a wide variety of applications such as human genetics, disease, and pathogens. The reason the Arkansas Micro & Nano Systems lab is involved with research in DNA sequencing is due to the current, leading industry method. Nanopore sequencing was developed by Oxford Nanopore Technology in which its sequencing method separates double stranded DNA to electrically characterize individual nucleotides traveling through a charged nanopore. Unfortunately, nanopore sequencing uses biological materials that require a shelf life and drives high cost. Therefore, the Arkansas Micro & Nano Systems lab has developed …

Study Of The Chemical Fabrication Process Of Nsom Probes And The Modification Of The Probe Surface, Muhammad Nazmul Hussain

Theses and Dissertations

Near-field scanning optical microscopy (NSOM) merges scanning probe technology with the power of high-resolution optical microscopy and provides a natural view into the nanoworld. NSOM requires tapered probes with subwavelength optical apertures and wide cone angles to efficiently channel the illumination light to the tip apex so that it can acquire optical images beyond the diffraction limit. Tapered probes with a range of cone angles can be fabricated through chemical etching of optical fibers using hydrofluoric acid (HF) by varying the etching time. Apart from their use for NSOM imaging, such optical probes can also be transformed into nanosensors by …

Towards Highly Sensitive Capacitance Measurements Of A Quantum Anomalous Hall Phase In Van Der Waal Heterostructures, Kayla Cerminara

UNLV Theses, Dissertations, Professional Papers, and Capstones

One of the pioneering achievements in condensed matter physics of the 20th century is the observation of the quantum Hall e↵ect (QHE) in which the Hall resistance in a two-dimensional (2D) sample takes on quantized values in the presence of a strong perpendicular magnetic field. The precise quantization of the hall resistance to one part in a billion has provided a practical, worldwide resistance standard. A long-standing goal has been to realize a similar state of matter but without the need of a strong quantizing magnetic field. The quantum anomalous Hall e↵ect (QAHE) is such a state that is predicted …

Synthesis Of Monodisperse Nanoscintillators At High Temperatures For Biomedical Relevant Applications, Eric Zhang

All Dissertations

Luminescent sub-100 nm particulates continuously generate immense research interest in the biomedical field for imaging, theranostics, and optogenetics. Conventionally, upconversion nanoparticles or UV activated semiconductors are studied, however these materials are limited by biological barriers such as the skin which reduces the penetration depth of these excitation sources, tissue's auto- fluorescence, and toxicity. One approach to overcome these challenges is to use nanoscintillators (sub-100 nm materials that can generate visible light using high energy excitation sources such as x-rays) which can generate light locally to the human body. Numerous scintillators have been reported since the discovery of x-rays from the …

Rational Design Of Composite Nanomaterials For Water Treatment Applications, Mariana Marcos-Hernandez

Open Access Theses & Dissertations

Water quantity and quality have been affected in communities all around the world due to population growth, pollution, changes in land use, and climate change. In order to cope with existing and anticipated water demands and shortages, the use of treated or reclaimed water is an ongoing alternative that has helped communities all over the world address this problem. The adaptation of nanotechnology to traditional water and wastewater treatment processes offers new opportunities in technological developments. Unique size-dependent properties such as: high surface to mass ratio, high reactivity, high sorption capacities, fast dissolution, superparamagnetism, among others, provide high-tech efficient materials …

Surface-Functionalized Chemiresistive Films That Exploit H-Bonding, Cation-Pi, And Metal-Halide Interactions., Prasadanie Karunarathna Adhihetty

Electronic Theses and Dissertations

The development of gas sensors for detection of volatile organic compounds (VOCs) has been of interest in the sensing field for decades. To date, the use of metal nanoparticle-based chemiresistors for trace VOC detection, particularly gold nanoparticle-based sensors, is of great interest due to their high chemical stability, ease of synthesis, unique optical properties, large surface to volume ratio, and high level of conductivity. Much effort has been devoted towards gold monolayer protected clusters (Au MPCs) as chemiresistors to detect harmful VOCs. The present thesis documents the results of our efforts to exploit the advantages of functionalized Au MPCs chemiresistors …

A Performance Guide For Four Songs By Francisco Mignone, Amanda Mara Rizzotto Vidal Pessoa

UNLV Theses, Dissertations, Professional Papers, and Capstones

The scope of this document is to demonstrate the richness and diversity to be found in the art song genre from countries outside of the standard repertoire, specifically focusing on the Brazilian composer Francisco Mignone. The purpose of this document is to provide performance practice guidelines for four selected pieces by Francisco Mignone: No Meio do Caminho (1938), Pregão (1947), Si eu sei o que é saudade (1976), and Valsa-Vocalise (1972). They exemplify expressions of Brazilian national identity through the music selected. Furthermore, it provides a brief background on the composer and his compositional style phases, and context for the …

Structural Evolution During Synthesis And Annealing Of Platinum-Nickel Bimetallic Nanoparticles, Xiner Lu

All Theses

In the past years, there has been an increasing interest in synthesizing Pt alloy nanocrystals to achieve high catalytic performance for energy-related applications. Pt-Ni nanoparticles (NPs) have shown high electrocatalytic activity for electrocatalysis and thermal catalysis. However, the stability of surface structures and compositions still needs to be improved to obtain better long-term catalytic stability. It is noted that thermal annealing can adjust the surface structures and compositions to improve the stability. Transmission electron microscopy (TEM) plays a vital role in characterizing the morphology, structure, and composition of nanoparticles. Specifically, the utilization of in situ TEM can allow for observing …

Photoassisted Nanoscale Memory Resistors, Amir Shariffar

Graduate Theses and Dissertations

Memristors or memory resistors are promising two-terminal devices, which have the potential to revolutionize current electronic memory technologies. Memristors have been extensively investigated and reported to be practical devices, although they still suffer from poor stability, low retention time, and laborious fabrication processes.

The primary aim of this project was to achieve a device structure of quantum dots or thin films to address a fundamental challenge of unstable resistive switching behavior in memristors. Moreover, we aimed to investigate the effects of light illumination in terms of intensity and wavelength on the performance of the fabricated memristor. The parameters such as …

Alpha Synuclein: A Therapeutic Target And Biomarker For Parkinson’S Disease, Max Chase

USF Tampa Graduate Theses and Dissertations

Parkinson’s Disease is the second most common neurodegenerative disease after Alzheimer’s Disease, and the most common motor disorder. In fact, nearly a third of those with AD have PD. A major hallmark of PD is the appearance of Lewy Bodies, proteinaceous cytoplasm inclusions, that build up and spread throughout the CNS in a prion like fashion. The major component of these Lewy Bodies is a protein called alpha-synuclein. Alpha-syn is a 14kDa protein made of 140 amino acids and found in the presynaptic ends of CNS neurons, acting as a chaperone and regulator. The protein is also found in the …

Stability Analysis Of Delay-Driven Coupled Cantilevers Using The Lambert W-Function, Daniel Siebel-Cortopassi

USF Tampa Graduate Theses and Dissertations

A coupled delay-feedback system of two cantilevers can yield greater sensitivity than that of asingle cantilever system, with potential applications in atomic force microscopy. The Lambert W-function analysis concept for delay differential equations is used to more accurately model the behavior of specific configurations of these cantilever systems. We also use this analysis concept to find parameters which yield stability for greater parameter ranges, of the delay differential equations. The Q factor, or quality factor, is the ratio of energy stored in the system, to the energy lost per fixed oscillation/movement cycle. Having stability of the cantilevers corresponds to the …

Development Of High Performance Cathodes: From Liquid To Solid-State Batteries, Sixu Deng

Electronic Thesis and Dissertation Repository

Lithium-ion batteries (LIBs) are critical for the development of electric vehicles (EVs) because of their higher operating voltages compared to other energy storage technologies. However, the development of start-of-the-art LIBs touched the ceiling because of three main challenges: safety risks, limited energy density, and high cost. Accordingly, all-solid-state lithium-ion batteries (ASSLIBs) have recently emerged as promising alternative batteries for next-generation EVs because of their ability to overcome the drawbacks of conventional LIBs. Whether in conventional liquid LIBs or ASSLIBs, cathode materials are crucial in determining the overall performance. Hence, this thesis focuses on understanding the degradation mechanism of cathode interfaces …

Detection Of Trace Heavy Metals In Water: Development Of Electrochemical Sensors, Quang Lam, Joel Mututeke

Symposium of Student Scholars

The presence of heavy metals in our ecosystem poses significant ecological and physiological consequences. As a result, numerous techniques are developed for the detection of contaminants in aqueous solutions. However, early and trace detection of such contaminants still remains a challenge. Amongst many techniques, electrochemistry driven sensors have shown promise due to their possibility of miniaturization and low-cost. Our research investigates the use of electrically conducting polymer and atomically thin carbon materials as electrodes towards the development of electrochemical sensor. Nanocomposite electrode films have been synthesized and fabricated using in-situ polymerization technique and the relationship between number of cycles of …

Block Copolymer Directed Self-Assembly: Exploring The Efficacy Of Applications In Semiconductor Fabrication, Jakin Bryce Delony

USF Tampa Graduate Theses and Dissertations

Over the course of the past 80 years, semiconductor devices have become increasingly ubiquitous in everyday life.From constructing mainframes that encompassed entire rooms during the 1940s, to inventing personal computers in the 1980s, to developing progressively faster smartphones and wearable technology in the 2010s, the primary driving force behind the Digital Revolution has been increasing transistor counts, and thus computing power, via incremental improvements in optical lithography. In 1965, Intel co-founder Gordon Moore boldly predicted that the transistor density of semiconductor devices would double approximately every 18-24 months. While this prediction -- now colloquially referred to as Moore's Law -- …

Ultra-Broadband And Polarization-Insensitive Metasurface Absorber With Behavior Prediction Using Machine Learning, Shobhit K. Patel, Juveriya Parmar, Vijay Katkar, Fahad Ahmed Al-Zahrani, Kawsar Ahmed

Mechanical & Materials Engineering Faculty Publications

The solar spectrum energy absorption is very important for designing any solar absorber. The need for absorbing visible, infrared, and ultraviolet regions is increasing as most of the absorbers absorb visible regions. We propose a metasurface solar absorber based on Ge₂Sb₂Te₅ (GST) substrate which increases the absorption in visible, infrared and ultraviolet regions. GST is a phase-changing material having two different phases amorphous (aGST) and crystalline (cGST). The absorber is also analyzed using machine learning algorithm to predict the absorption values for different wavelengths. The solar absorber is showing an ultra-broadband response covering a 0.2–1.5 …

Method Of Making Hinged Self-Referencing Fabry–Pérot Cavity Sensors [U.S. Patent Us11287575b2], Jeremiah C. Williams, Hengky Chandrahalim

Faculty Publications

A method is provided for fabricating a passive optical sensor on a tip of an optical fiber. The method includes perpendicularly cleaving a tip of an optical fiber and mounting the tip of the optical fiber in a specimen holder of a photosensitive polymer three-dimensional micromachining machine. The method includes forming a three-dimensional microscopic optical structure within the photosensitive polymer that comprises a two cavity Fabry-Perot Interferometer (FPI) having a hinged optical layer that is pivotally coupled to a suspended structure. The method includes removing an uncured portion of the photosensitive polymer using a solvent. The method includes depositing a …