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Microwave-Assisted Synthesis, Characterization, and Photophysical Properties of New Rhenium(I) Pyrazolyl-Triazine Complexes

Description: The reaction of the chelating ligand 4-[4,6-bis(3,5-dimethyl-1H-pyrazol-1-yl)-1,3,5-triazin-2-yl]-N,N-diethyl-benzenamine, L, with pentacarbonylchlororhenium by conventional heating method produces the complexes fac-[ReL(CO)3Cl2] and fac-[Re2L(CO)6Cl2] in a period of 48 hours. The use of microwaves as the source of heat and the increase in the equivalents of one of the reactants leads to a more selective reaction and also decreases the reaction time to 1 hour. After proper purification, the pho… more
Date: May 2010
Creator: Salazar Garza, Gustavo Adolfo
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Design, Synthesis and Screening of Homoleptic and Heteroleptic Platinum(ii) Pyridylazolate Complexes for N-type Semiconducting and Light-emitting Devices

Description: A series of heteroleptic and homoleptic platinum(II) complexes has been synthesized and characterized towards their use in thin film devices such as organic light-emitting diodes (OLEDs) and organic thin film transistors (OTFTs). Pyridylpyrazolate- and pyridyltetrazolate-containing ligands were selected due to their structural rigidity and ease of functionalization. Single-crystal x-ray diffraction studies of two selected heteroleptic complexes show strong aggregation with preferential stacking… more
Date: August 2012
Creator: Oswald, Iain William Herbert
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Characterization of Ionic Liquid As a Charge Carrier for the Detection of Neutral Organometallic Complexes Using Electrospray Ionization Mass Spectrometry

Description: A novel application of ionic liquid as a charge carrier for the analysis and detection of neutral organometallic complexes using a mass spectrometer has been presented. The mass spectrometer detects only charged compounds which raise a difficulty in analyzing a neutral molecule that lacks a basic site to associate with charge. Therefore, an effective way of providing charge has always been an area of keen interest in the field of mass spectrometry. Ionic liquids have a very fascinating property… more
Date: August 2012
Creator: Joshi, Ubisha
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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A New Chromophoric Organic Molecule Toward Improved Molecular Optoelectronic Devices

Description: The characterization of 2,3,6,7,10,11-hexabromotriphenylene, Br6TP, is presented toward its potential use as an n-type organic semiconductor and metal-free room temperature phosphor. The crystal structure shows both anisotropic two-dimensional BrBr interactions and inter-layer ?-stacking interactions. Photophysical characteristics were evaluated using solid-state photoluminescence and diffuse reflectance spectroscopies, revealing significantly red-shifted excitations in the visible region for… more
Date: December 2012
Creator: Halbert, Jason Paul
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Synthesis of Tethering Group on Borylazadipyrromethene Dyes to Apply to Photogalvanic Dye-sensitized Solar Cells

Description: This is my thesis research on the preparation of borylazadipyrromethene (azaBODIPY) dyes bearing an anchoring group, such as a carboxylic acid group, at the β-pyrrolic position of the azadipyrromethene scaffold. Carboxylate groups form covalent bonds to oxide semiconductors such as TiO2 (n-type) or Cu2O (p-type) in dye-sensitized solar cells (DSCs) or photogalvanic dye-sensitized solar cells (P-DSCs). Oxide-binding azaBODIPY dyes can be used to investigate the rate and mechanism of electron inj… more
Date: August 2014
Creator: Park, Eunsol
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Supramolecular Solar Cells

Description: Supramolecular chemistry - chemistry of non-covalent bonds including different type of intermolecular interactions viz., ion-pairing, ion-dipole, dipole-dipole, hydrogen bonding, cation-p and Van der Waals forces. Applications based on supramolecular concepts for developing catalysts, molecular wires, rectifiers, photochemical sensors have been evolved during recent years. Mimicking natural photosynthesis to build energy harvesting devices has become important for generating energy and solar f… more
Date: August 2012
Creator: Subbaiyan, Navaneetha Krishnan
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Substitution Effects of Phenothiazine and Porphyrin Dyes in Dye-sensitized Solar Cells

Description: The details of dye sensitized solar cells was explained and phenothiazine and porphyrin based dyes were synthesized for use in DSSCs. DSSCs offer a unique and cost effective method of renewable energy. DSSCs are characterized through various tests, with the overall efficiency, η, bearing the greatest importance. Incident photon to current conversion efficiency, or IPCE, is also another important characterization of DSSCs. Effect of positioning of the cyanoacrylic acid anchoring group on ring… more
Date: December 2013
Creator: Hart, Aaron S.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Electrochemically Deposited Metal Alloy-silicate Nanocomposite Corrosion Resistant Materials

Description: Zinc-nickel ?-phase silicate and copper-nickel silicate corrosion resistant coatings have been prepared via electrochemical methods to improve currently available corrosion resistant materials in the oil and gas industry. A layered silicate, montmorillonite, has been incorporated into the coatings for increased corrosion protection. For the zinc nickel silicate coatings, optimal plating conditions were determined to be a working pH range of 9.3 -9.5 with a borate based electrolyte solution, res… more
Date: May 2013
Creator: Conrad, Heidi Ann
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Electrochemical Synthesis and Applications of Layered Double Hydroxides and Derivatives

Description: Layered double hydroxides (LDH) are a class of anionic clay with alternating layers of positive and negative charge. A metal hydroxide layer with divalent and trivalent metals with a positive charge is complemented by an interlayer region containing anions and water with a negative charge. The anions can be exchanged under favorable conditions. Hydrotalcite (Mg6Al2(OH)16[CO3]·4H2O) and other variations are naturally occurring minerals. Synthetic LDH can be prepared as a powder or film by numero… more
Date: August 2015
Creator: Kahl, Michael S.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Molecules and Materials for Excitonic Solar Cells Using P-type Metal Oxide Semiconductors

Description: This dissertation has two intersecting foci; firstly, the discovery of a new methodology for the growth of high surface area cuprous oxide (Cu2O) substrates. Secondly, the synthesis and characterization of electron-accepting molecules, and their incorporation into excitonic solar cells (XSCs) using the Cu2O substrates as electrodes. Increasing the surface area of the semiconductor creates more locations for charge transfer to occur thus increasing the overall efficiency of the device. Zinc oxid… more
Date: August 2015
Creator: Haynes, Keith M.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Synthesis of Peropyrene and Tetracene Derivatives for Photochemical Applications

Description: A novel route for the synthesis of the polycyclic aromatic hydrocarbon peropyrene (Pp) is reported along with the efforts to synthesize derivatives of Pp, 2,2′- and 5,5′-linked tetracene dimers as candidates for study as singlet fission materials in photovoltaic devices. Peropyrene was synthesized by the McMurry coupling conditions from phenalenone and low-valent titanium species. The crystal structure of Pp is formed by π-stacked molecular pairs in a herringbone arrangement. The direct functio… more
Date: May 2015
Creator: Rodríguez López, Marco Tulio
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Diimine(dithiolate)platinum(ii) Chromophores: Synthesis, Spectroscopy, and Material Applications

Description: A series of 28 square-planar dithiol(diimine)platinum(II) chromophoric complexes have been synthesized, characterized, and evaluated for potential efficacy in sensitization of solid state photovoltaic devices to the near-infrared regions of the electromagnetic spectrum. The effect of molecular stacking in the solid state and self-association in solution are shown to influence spectral, electronic, and magnetic properties of the chromophores. Such properties are investigated in the pure form and… more
Date: August 2014
Creator: Browning, Charles
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Cu Electrodeposition on Ru-Ta and Corrosion of Plasma Treated Cu in Post Etch Cleaning Solution

Description: In this work, the possibility of Cu electrodeposition on Ru-Ta alloy thin films is explored. Ru and Ta were sputter deposited on Si substrate with different composition verified by RBS. Four point probe, XRD, TEM and AFM were used to study the properties of Ru-Ta thin films such as sheet resistance, crystallinity, grain size, etc. Cyclic voltammetry is used to study the Cu electrodeposition characteristics on Ru-Ta after various surface pretreatments. The results provide insights on the rem… more
Date: August 2011
Creator: Sundararaju Meenakshiah Pillai, Karthikeyan
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Acceptor-sensitizers for Nanostructured Oxide Semiconductor in Excitonic Solar Cells

Description: Organic dyes are examined in photoelectrochemical systems wherein they engage in thermal (rather than photoexcited) electron donation into metal oxide semiconductors. These studies are intended to elucidate fundamental parameters of electron transfer in photoelectrochemical cells. Development of novel methods for the structure/property tuning of electroactive dyes and the preparation of nanostructured semiconductors have also been discovered in the course of the presented work. Acceptor sensiti… more
Date: August 2014
Creator: Berhe, Seare Ahferom
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Interfacial Characterization of Chemical Vapor Deposition (Cvd) Grown Graphene and Electrodeposited Bismuth on Ruthenium Surface

Description: Graphene receives enormous attention owing to its distinctive physical and chemical prosperities. Growing and transferring graphene to different substrates have been investigated. The graphene growing on the copper substrate has an advantage of low solubility of carbon on the copper which allow us to grow mostly monolayer graphene. Graphene sheet of few centimeters can be transferred to 300nm silicon oxide and quartz crystal pre-deposited with metal like Cu and Ru. Characterization of the gra… more
Date: May 2014
Creator: Abdelghani, Jafar
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Rational Design of Metal-organic Electronic Devices: a Computational Perspective

Description: Organic and organometallic electronic materials continue to attract considerable attention among researchers due to their cost effectiveness, high flexibility, low temperature processing conditions and the continuous emergence of new semiconducting materials with tailored electronic properties. In addition, organic semiconductors can be used in a variety of important technological devices such as solar cells, field-effect transistors (FETs), flash memory, radio frequency identification (RFID) t… more
Date: December 2012
Creator: Chilukuri, Bhaskar
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Self-assembly Polymeric Nanoparticles Composed of Polymers Crosslinked with Transition Metals for Use in Drug Delivery

Description: A major drawback of chemotherapy is the lack of selectively leading to damage in healthy tissue, which results in severe acute side effects to cancer patients. The use of nanoparticles as a drug delivery system has emerged as novel strategy to overcome the barriers of immunogenic response, controlled release of therapeutic, and targeting the toxicity only to cancerous cells. In this study, polymeric nanoparticles composed of transition metals and particles derived from natural biopolymers hav… more
Date: December 2015
Creator: Nguyen, Duong Thuy
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Synthesis of Novel Organic Chromophores and Their Characterization

Description: Nonlinear organic liquids that exhibit two-photon absorption (TPA) function as good optical limiters for sensor protection from laser pulses. L34 (4-butyl-4'-propyl-diphenylethyne) is a liquid organic compound exhibiting nonlinear optical absorption. A thiol- derivatized analog of L34 (“thiol-L34”) was prepared to bind the molecules to the surface of gold nanoparticles. Surface binding is necessary to investigate synergy between nonlinear optical absorption of gold nanoparticles and thiol-L34. … more
Date: December 2014
Creator: Pokharel, Sundari D.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Fundamental Studies of Copper Bimetallic Corrosion in Ultra Large Scale Interconnect Fabrication Process

Description: In this work, copper bimetallic corrosion and inhibition in ultra large scale interconnect fabrication process is explored. Corrosion behavior of physical vapor deposited (PVD) copper on ruthenium on acidic and alkaline solutions was investigated with and without organic inhibitors. Bimetallic corrosion screening experiments were carried out to determine the corrosion rate. Potentiodynamic polarization experiments yielded information on the galvanic couples and also corrosion rates. XPS and FTI… more
Date: May 2014
Creator: Koskey, Simon Kibet
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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