Open Access. Powered by Scholars. Published by Universities.®

Chemistry Commons

Open Access. Powered by Scholars. Published by Universities.®

PDF

University of Massachusetts Amherst

Theses/Dissertations

2014

Discipline
Keyword
Publication

Articles 1 - 30 of 34

Full-Text Articles in Chemistry

Engineered Nanoparticles For Detection And Treatment Of Bacteria And Biofilms, Xiaoning Li Nov 2014

Engineered Nanoparticles For Detection And Treatment Of Bacteria And Biofilms, Xiaoning Li

Doctoral Dissertations

Rapid and sensitive detection and identification of bacteria woud control and prevent bacterial infection and disease, enhancing the likelihood of early diagnosis and treatment. Especially developing effective biosensor for identification of bacteria species involved in formation of biofilms, which cause chronic and persistent diseases, would promote diagnostic and therapeutic efficiency. Conventional detection methods are limited by sensitivity and required time. First part of my research has been focused on developing a rapid, simple, and sensitive biosensor aiming at portable device application for detection of bacteria in water samples. This sensor is able to detect bacteria at low concentration and generate …


Functional Nanocomposites From Self-Assembly Of Block Copolymers With Nanoparticles, Xinyu Wang Nov 2014

Functional Nanocomposites From Self-Assembly Of Block Copolymers With Nanoparticles, Xinyu Wang

Doctoral Dissertations

This dissertation studied the proper distribution and location control of nanoparticles (NPs) within block copolymer (BCP) templates. A facile ligand exchange reaction was introduced for the hydrophilic magnetic NPs (MNPs) that are readily dispersed in polar solvents with outstanding stability. Small molecule ligands were selected to associate strongly with particle surfaces, provide hydrophilic termini for polarity matching with polar solvents, and offer the potential for hydrogen-bonding interactions to facilitate NP incorporation into polymers. Areal ligand densities of NPs indicated a significant increase in the ligand coverage after the exchange reaction. Hydrophilic MNPs were shown to drive the self-assembly of BCPs …


Flexible Tethers In Multi-Chromophoric Systems: Linking Photophysics With Assembly, Jeffrey M. Lucas Nov 2014

Flexible Tethers In Multi-Chromophoric Systems: Linking Photophysics With Assembly, Jeffrey M. Lucas

Doctoral Dissertations

Aggregation and folding events in conjugated polymers have a dramatic effect on the photophysics, and in turn, the efficiency of said species in organic electronic devices. The factors that lead to twisting, bending and folding in conjugated polymers have been studied in numerous polymeric materials, but due to the variability of these events, they remain poorly understood. To probe the spectroscopic signatures of folding and to link them with conformational and morphological features formed by these species in the solid state, a series of alternating co-polymers were then synthesized, incorporating the 2- and 4-carbon tethers with oligo-phenylenevinylene derivatives. Static absorption, …


Engineering Surface Functionality Of Nanoparticles For Biological Applications, Yi-Cheun Yeh Nov 2014

Engineering Surface Functionality Of Nanoparticles For Biological Applications, Yi-Cheun Yeh

Doctoral Dissertations

Engineering the surface functionality of nanomaterials is the key to investigate the interactions between nanomaterials and biomolecules for potent biological applications such as therapy, imaging and diagnostics. My research has been orientted to engineer both of the surface monolayers and core materials to fabricate surface-functionalized nanomaterials through the synergistic multidisciplinary approach that combine organic chemistry, materials science and biology. This thesis illustrates the design and synthesis of the surface-funcitonalized quantum dots (QDs) and gold nanoparticles (AuNPs) for the fundamental studies and practical applications. For QDs, A new class of cationic QDs with quaternary ammonium derivatives was synthesized to provide permanent …


Patterning And Mechanical Analysis Of Fiber-Based Materials, Samuel A. Pendergraph Nov 2014

Patterning And Mechanical Analysis Of Fiber-Based Materials, Samuel A. Pendergraph

Doctoral Dissertations

The ability to define and control the topography of a surface has been studied extensively due to its importance in a wide variety of applications. The control of a non-planar topography would be very valuable since a number of structures that are pervasive in artificial applications (e.g. fibers, lenses) are curved interfaces. This potential of enabling applications that incorporate non-planar geometries was the motivation for this thesis. The first study of this thesis comprises the study of patterning the circumference of micrometer sized fibers. Specifically, a unique technique was described to pattern the fiber with a periodic array of colloids. …


The Discovery And Study Of Fluvirucin B1 Polyketide Synthase, Tsung-Yi Lin Nov 2014

The Discovery And Study Of Fluvirucin B1 Polyketide Synthase, Tsung-Yi Lin

Doctoral Dissertations

Rapidly decreasing numbers of viable therapeutic leads in the pharmaceutical pipeline demand new, sustainable methods for improved drug discovery and development. Despite vast improvements in de novo drug design and target recognition, Nature remains the richest source of small molecule therapeutics. Among many natural products, polyketides are not only the most promising ones for developing new antibiotic leads, but also exhibit unusually high therapeutic value ranging from clinical use as anticancer, antiviral, and immunosuppressant drugs. Modular polyketide synthases (PKSs) are dedicated nano-machinery that can be manipulated to produce a structurally diverse library for drug discovery programs. The ability to manipulate …


Understanding Structure-Property Relationships At The Nano-Bio Interface For Delivery Applications, Krishnendu Saha Nov 2014

Understanding Structure-Property Relationships At The Nano-Bio Interface For Delivery Applications, Krishnendu Saha

Doctoral Dissertations

The surface chemistry of the nanomaterials creates an effective interface between two entirely different worlds: nanotechnology and biology. Understanding the interaction between nanomaterial surface chemistry and biological entities can be useful for a wide variety of biomedical applications as well as can provide crucial information for nanotoxicology. In my research, I have used gold nanoparticles as a model platform to synthesize a family of nanoparticles with atomic level control of their surface properties and probe their interaction with biological systems. First part of my research focused on the understanding the uptake mechanisms, toxicity, and hemolytic properties of cationic nanoparticles, an …


Guanidinium-Rich Romp Polymers Drive Phase, Charge, And Curvature-Specific Interactions With Phospholipid Membranes, Michael T W Lis Nov 2014

Guanidinium-Rich Romp Polymers Drive Phase, Charge, And Curvature-Specific Interactions With Phospholipid Membranes, Michael T W Lis

Doctoral Dissertations

Protein transduction domains (PTDs) and their and their synthetic mimics are short sequences capable of unusually high uptake in cells. Several varieties of these molecules, including the arginine-rich Tat peptide from HIV, have been extensively used as vectors for protein, DNA, and siRNA delivery into cells. Despite the wide-ranging utility of PTDs and their mimics, their uptake mechanism is still under considerable debate. How the molecules are able to cross phospholipid membranes, and what structural components are necessary for optimal activity are poorly understood. This thesis explores how PTDMs interact with phospholipid membrane phase, anionic lipid content and negative Gaussian …


Mass Spectrometry Based Experimental Strategies To Characterize Native And Non-Native Disulfide Bonds In Cysteine-Rich Protein Therapeutics, Adriana Z. Kita Nov 2014

Mass Spectrometry Based Experimental Strategies To Characterize Native And Non-Native Disulfide Bonds In Cysteine-Rich Protein Therapeutics, Adriana Z. Kita

Doctoral Dissertations

The impact post-translational modifications (PTMs) can have on the structure, function, and immunogenicity of protein therapeutics makes it especially important for these protein-based treatments to be well characterized. Mass spectrometry has become instrumental in the examination of enzymatic and non-enzymatic PTMs. Disulfide bonds fall into both of these categories in which native disulfide bonds are formed in the ER by disulfide mediated enzymes and non-native disulfide bonds are often formed by non-enzymatic reducing/oxidizing reactions. Disulfide bonds are particularly important for protein folding and reinforcing higher order structure, and are typically characterized by LC-MS of non-reduced peptides. However, characterizing the disulfide …


Nanoparticle Building Blocks For Functional Structures, Youngdo Jeong Nov 2014

Nanoparticle Building Blocks For Functional Structures, Youngdo Jeong

Doctoral Dissertations

A major goal in material science is achieving a desired function using structures fabricated with designed building blocks. Advanced synthetic and self-assembly techniques allow various nanomaterials to become promising building blocks, providing the control of the interaction between building blocks. The unique properties of nanomaterials can be transferred to structured systems. Among nanomaterials, inorganic nanoparticles such as gold nanoparticles (AuNPs), magnetic particles, and quantum dots (QDs) provide useful physical properties stemming from their inorganic core, large surface areas, and oriented surface functionalities. My research has focused on fabricating functional systems using gold nanoparticles (AuNPs), manipulating the interaction between AuNPs, bio-entities, …


Factor Inhibiting Hif's (Fih) Structure Controls O2 Activation And Reactivity, John A. Hangasky Iii Nov 2014

Factor Inhibiting Hif's (Fih) Structure Controls O2 Activation And Reactivity, John A. Hangasky Iii

Doctoral Dissertations

Factor Inhibiting HIF (FIH) is a Fe(II)-αKG dependent oxygenase that acts as a cellular oxygen sensor in humans. FIH regulates the transcriptional activity of the hypoxia-inducible factor-1 (HIF-1a or HIF), a transcription factor responsible cellular O2 homeostasis. Hydroxylation of the target residue HIF-Asn803, found in the C-terminal transactivation domain (CTAD), inactivates HIF-dependent gene expression. Central to FIH’s function is the activation of O2 after CTAD binding. The mechanistic and structural features of FIH leading to tight coupling between CTAD binding and subsequent O2-activation and reactivity are key for efficient O2 sensing. Our mechanistic …


Functional Nanoparticles At Interfaces: Emulsion Stabilization And Triggered Inversion, Caroline Laure Marie Miesch Nov 2014

Functional Nanoparticles At Interfaces: Emulsion Stabilization And Triggered Inversion, Caroline Laure Marie Miesch

Doctoral Dissertations

Encapsulation of materials can be performed through the stabilization of fluid-fluid interfaces and the formation of emulsion droplets, which is commonly achieved with surfactants, including small molecules and polymers, as well as particles that are, typically, micron-scale in diameter. The worked contained in this dissertation centered on droplets that are stabilized by nanoparticles, including metallic nanoparticles and semiconductor quantum dots, which bring the conductive and fluorescent properties inherent to such nanoparticles into the droplet construction. Double emulsion droplets, both oil-in-water-in-oil (o/w/o) and water-in-oil-in-water (w/o/w) were formed using nanoparticles as the only surfactant in solution. Different types of nanoparticles were found …


On The Assembly Of Functionalized Cdse Nanorods, Sirinya Chantarak Nov 2014

On The Assembly Of Functionalized Cdse Nanorods, Sirinya Chantarak

Doctoral Dissertations

High aspect ratio (AR) CdSe nanorods (NRs) of well-defined sizes were synthesized to optimize the geometries of photovoltaic devices made from these nanorods. Long-range ordering of hexagonal arrays of high AR NRs is achieved by a combination of controlled solvent evaporation and the use of an applied electric field. Regioregular P3HT chains and oligothiophene were functionalized with ligating end-groups to provide contact to the NRs. Vertically oriented assemblies of CdSe NRs functionalized with terthiophene and polythiophene are also obtained. Hexagonal arrays of these nanocomposites were characterized by transmission electron microscopy (TEM). Three types of polythiophenes: poly(3-hexylthiol thiophene), poly(3-hexylamine thiophene), and …


Volatile Profiles And Resistance To Herbivory In Eastern Hemlock, Elizabeth A. Mckenzie Nov 2014

Volatile Profiles And Resistance To Herbivory In Eastern Hemlock, Elizabeth A. Mckenzie

Masters Theses

Eastern hemlock hosts the hemlock woolly adelgid, an introduced sap-feeding insect that causes rapid deterioration of the host. Like most conifers, eastern hemlock produces a variety of constitutive and induced defenses, primarily terpenoids. To explore the relationship of terpenoid defenses with adelgid infestations, we artificially infested hemlocks at a forest site and a plantation site, and compared their terpenoid concentrations to those in control trees. Infested trees showed lower terpenoid concentrations than control trees, suggesting that eastern hemlock not only fails to induce production of terpenoids in response to adelgid infestation, but becomes less able to produce carbon-based defenses due …


Modification Of Gold Nanoparticles For Sers Application In Emulsion And Lipid Systems, Michael J. Driver Nov 2014

Modification Of Gold Nanoparticles For Sers Application In Emulsion And Lipid Systems, Michael J. Driver

Masters Theses

Gold nanoparticles produced using the Turkevich method were able to have their hydrophobicity modified using octanethiol in a novel method for SERS application. Both amphiliphic GNPs and hydrophobic GNPs were produced and differentiated by Raman signals. The amphiliphic GNPs were able to enhance the SERS signals of the protein emulsifier in the emulsion in situ and the hydrophobic GNPs were able to enhance the SERS signals from canola oil. Further purification of the hydrophobic GNPs proved to have higher enhancement and sensitivity, but still poor consistency which is typical of SERS. Monitoring lipid oxidation using Raman and SERS using alternative …


Mass Spectrometric Characterization And Imaging Of Nanoparticles In Biological Samples, Bo Yan Aug 2014

Mass Spectrometric Characterization And Imaging Of Nanoparticles In Biological Samples, Bo Yan

Doctoral Dissertations

Nanoparticles (NPs) are being investigated widely for use in biomedical applications such as imaging, drug delivery, and cancer therapy due to their small size and readily tunable properties. The ability to accurately characterize NPs and monitor their spatial distributions is highly desirable for effective use of NPs and evaluation of their potential adverse environmental, health, and safety effects. In this dissertation, a simple, fast, and sensitive method based on laser desorption/ionization mass spectrometry (LDI-MS) to characterize and track NPs in biological systems has been developed. This method is especially well suited for characterizing core-shell structured NPs, such as quantum dots …


Functional Phosphorylcholine Polymers: Prodrugs And Biomaterials, Samantha B.M. Page Aug 2014

Functional Phosphorylcholine Polymers: Prodrugs And Biomaterials, Samantha B.M. Page

Doctoral Dissertations

This thesis describes the synthesis and applications of multifunctional, hydrophilic polymers consisting of a methacrylate backbone and zwitterionic phosphorylcholine (PC) pendent groups, prepared by free radical polymerization of the zwitterionic monomer, 2-methacryloyloxyethyl phosphorylcholine (MPC). Advances in polymer chemistry, applied to PC polymers, allowed for the preparation of well-defined structures with controlled molecular weight, narrow polydispersity, and facile incorporation of functional comonomers, giving breadth to the range of materials accessible for different applications. Built-in functionality included fluorophores and reactive groups for post-polymerization transformations, such as drug conjugation or cross-linking. The ability to form well-defined structures based on the polyMPC backbone is …


Protein Behavior Directed By Heparin Charge And Chain Length, Burcu Baykal Minsky Aug 2014

Protein Behavior Directed By Heparin Charge And Chain Length, Burcu Baykal Minsky

Doctoral Dissertations

Glycosaminoglycans (GAGs), highly charged biological polyelectrolytes, are of growing importance as biomaterials and pharmaceutical drugs due to their immense range of physiological functions. They bind to many proteins; however, the degree of structural selectivity in GAG-protein interactions is largely unknown .Our studies have focused on the importance of heparin (a model GAG) charge and chain length in protein binding in order to explore its potential applications in biofunctional tissue scaffold materials, as polysaccharide drugs in anticoagulation, and as inhibitory agents in protein aggregation. We used electrospray ionization mass spectrometry, capillary electrophoresis, size exclusion chromatography, dynamic/static light scattering and electrostatic protein …


Morphology Characterization Of Low Band Gap Polymer-Based Organic Photovoltaics, Feng Liu Aug 2014

Morphology Characterization Of Low Band Gap Polymer-Based Organic Photovoltaics, Feng Liu

Doctoral Dissertations

In bulk heterojunction (BHJ) thin film organic photovoltaics (OPV), morphology control is critical to obtain good device efficiency. Nanoscale phase separation that creates bicontinuous interpenetrating structure on a size scale commensurate with exciton diffusion length (~10 nm) is thought to be the ideal morphology. Results obtained from this work indicate that morphology can be affected by chemical structure of the polymer, processing conditions, blending ratio and post treatments. Physical properties of the material, such as crystallinity, crystal orientation, material interactions and miscibility, surface energy and particle aggregations are critical for determining the morphology and thus the device performance. Previous investigations …


Spectroscopic Studies Of Non-Covalent Metal Ion-Ligand Interactions, Abdulkadir Kocak Aug 2014

Spectroscopic Studies Of Non-Covalent Metal Ion-Ligand Interactions, Abdulkadir Kocak

Doctoral Dissertations

Non-covalent interactions between metal ions and ligands such as water and methane have been extensively studied due to their biological and industrial importance. Gas phase studies can reveal the fundamental nature of these metal-ligand interactions. Photofragment spectroscopy is a powerful technique to investigate bond strengths, dissociation dynamics, molecular geometry and clustering and can be applied to electronic and vibrational spectroscopy. Using a home built apparatus, which combines ion production via laser ablation, separation via time-of-flight (TOF) mass spectrometry, laser excitation, and TOF fragment mass analysis, we have obtained electronic spectra of Co+(H2O) and vibrational spectra of …


Molecular Engineering Strategies For The Design And Synthesis Of New Organic Photovoltaic Materials, Paul J. Homnick Aug 2014

Molecular Engineering Strategies For The Design And Synthesis Of New Organic Photovoltaic Materials, Paul J. Homnick

Doctoral Dissertations

Dramatic improvements in organic photovoltaic device efficiency can be obtained by optimizing spectral absorbance and frontier molecular orbital (FMO) energies, increasing solid state exciton/charge mobility, and utilizing p-/n-type nanoarchitecture. Combining all of these properties into a new material presents a considerable synthetic challenge because potential commercial applications require materials that are high-performance and inexpensive. Thus, it is advantageous to design new materials using a versatile, modular synthetic approach that allows each design criterion to be engineered individually, in a synthetically efficient manner. Several strategies were successfully pursued using simple interchangeable electron donor and acceptor components as functional modules, which …


Visualizing And Controlling Charge Transport In Conjugated Polymer Networks And Films, Andrew Davis Aug 2014

Visualizing And Controlling Charge Transport In Conjugated Polymer Networks And Films, Andrew Davis

Doctoral Dissertations

VISUALIZAING AND CONTROLLING CHARGE TRANSPORT IN CONJUGATED POLYMER NETWORKS AND FILMS MAY 2014 ANDREW R. DAVIS, B.S., UNIVERSITY OF VIRGINIA M.S., UNIVERSITY OF MASSACHUSETTS AMHERST Ph.D., UNIVERSITY OF MASSACHUSETTS AMHERST Directed by: Professor Kenneth R. Carter The desire for more commercially feasible flexible electronic plastics has led to the development of increasingly complex conjugated polymer architectures and device geometries. Through these efforts, tremendous advances have been made in the design and performance of electronic devices fabricated with solution-processable semiconducting polymers. However, none of these materials have yet reached commercial maturity, so the opportunity for their further exploration from both a …


Creasing Instability Of Hydrogels And Elastomers, Dayong Chen Aug 2014

Creasing Instability Of Hydrogels And Elastomers, Dayong Chen

Doctoral Dissertations

CREASING INSTABILITY OF HYDROGELS AND ELASTOMERS MAY 2014 DAYONG CHEN, B.S., TIANJIN UNIVERISTY M.S., TIANJIN UNIVERSITY M.S., UNIVERSITY OF MASSACHUSETTS AMHERST Ph.D., UNIVERSITY OF MASSACHUSETTS AMHERST Directed by: Professor Ryan C. Hayward Soft polymers placed under compressive stress can undergo an elastic creasing instability in which sharp folds spontaneously form on the free surfaces. This process may play an important role in contexts as diverse as brain morphogenesis, failure of tires, and electrical breakdown of soft polymer actuators. While the creasing instability has been used for collotype printing since as early as the 1850s, the scientific appreciation of this instability …


Developing Spatial Reasoning Skills In General Chemistry Students, Deborah L. Carlisle Aug 2014

Developing Spatial Reasoning Skills In General Chemistry Students, Deborah L. Carlisle

Doctoral Dissertations

The study of organic chemistry requires the understanding and use of spatial relationships, which can be challenging for many students. Prior research has shown that there is a need to develop students’ spatial reasoning skills. To that end, this study implemented guided activities designed to strengthen students’ spatial skills, with the aim of preparing students for organic chemistry and other future STEM courses. Students, taking the second semester of a two-semester general chemistry course, engaged in these activities. This study followed a quasi experimental design, in which the experimental (n = 209) and the control group (n = 212) were …


Optical And Scanning Probe Studies Of Isolated Poly (3-Hexylthiophene) Nanofibers, Mina Baghgarbostanabad Aug 2014

Optical And Scanning Probe Studies Of Isolated Poly (3-Hexylthiophene) Nanofibers, Mina Baghgarbostanabad

Doctoral Dissertations

Plastic electronics have an essential role in the future technologies owing to their compelling characteristics such as light weight, biocompatibity, low cost fabrication, and tunable optoelectronic properties. However, the performance of polymer-based devices strongly depends on the efficiency of exciton formation and dynamics that are themselves strongly sensitive to polymer molecular packing and structural order. Therefore, the current challenge in achieving high efficiency is establishing a correlation between molecular packing and exciton coupling. P3HT nanofibers represent an attractive platform for studying optical and electronic properties of exciton coupling because their nominal (highly crystalline) internal chain packing structure is known. A …


Ligand-Receptor Interactions For Supramolecular Disassembly With Applications In Screening And Drug Delivery, Diego Amado Torres Aug 2014

Ligand-Receptor Interactions For Supramolecular Disassembly With Applications In Screening And Drug Delivery, Diego Amado Torres

Doctoral Dissertations

Proteins have the capacity to bind specific sets of compounds known as ligands, these are small molecules with a recurrent theme in their molecular design that is a characteristic exploited here to (i) identify particular affinities of small molecules for proteins with the aim of using them as ligands, inhibitors, or targeting moieties in more complex systems by means of a methodology that screens small molecules based on protein affinity; (ii) decorate a self-assembling supramolecular system at different positions, making it responsive to a complementary protein with the aim of exploring differences in disassembly and sensitivity of the release of …


Cell-Based Sensing Of Endocrine Disrupting Substances Using Fluorescent Protein-Gold Nanoparticle Complexes, Xian Wang Aug 2014

Cell-Based Sensing Of Endocrine Disrupting Substances Using Fluorescent Protein-Gold Nanoparticle Complexes, Xian Wang

Masters Theses

Developing a sensitive and effective in vitro bioassay to detect endocrine disrupting chemicals (EDCs) would reduce the cost, eliminate the possibility of low dose effects, detect the non-monotonic dose responses, and identify mechanisms of actions. The “chemical nose” sensing method using supramolecular complexes composed of cationic monolayer functionalized gold nanoparticles (AuNPs) and fluorescent proteins (FPs) can successfully distinguish serum proteins, mammalian cells, tissue lysates, and chemotherapeutic drug mechanisms. EDCs regulate target cells via genomic or non-genomic pathways in terms of proliferative effect and response time. In this thesis, green fluorescent protein-gold nanoparticle (GFP-AuNP) sensors were used to detect the proliferative …


Structural Analysis Of Proteins By Covalent Labeling And Mass Spectrometric Detection, Yuping Zhou Apr 2014

Structural Analysis Of Proteins By Covalent Labeling And Mass Spectrometric Detection, Yuping Zhou

Doctoral Dissertations

Covalent labeling and mass spectrometry are seeing increased use together as a way to obtain insight into the 3-dimensional structure of proteins and protein complexes. Several amino acid specific (e.g., diethylpyrocarbonate) and non-specific (e.g., hydroxyl radicals) labeling reagents are available for this purpose. Diethylpyrocarbonate (DEPC) is a promising labeling reagent because it can potentially probe up to 30% of the residues in the average protein and gives only one reaction product, thereby facilitating mass spectrometric analysis. It was recently reported, though, that DEPC modifications are labile for some amino acids. This dissertation focuses on the improvement of diethylpyrocarbonate (DEPC)-basedcovalent labeling …


Ionic Copolymers For Alkaline Anion Exchange Membrane Fuel Cells (Aaemfcs), Tsung-Han Tsai Apr 2014

Ionic Copolymers For Alkaline Anion Exchange Membrane Fuel Cells (Aaemfcs), Tsung-Han Tsai

Doctoral Dissertations

The advantages of alkaline anion exchange membrane fuel cells (AAEMFCs) over proton exchange membrane fuel cells is the motivation for this dissertation. The objectives of this dissertation were to develop durable membranes with high anion conductivity and an understanding of the ion conductivity relationship with morphology. The research results presented in this dissertation focuses on developing different architectures of ionic copolymers including diblock copolymers and random copolymers for AAEMFCs. A novel, and stable cobaltocenium cation, was incorporated into polymer for stable AAEM. Because of its 18 electron closed valence-shell configuration, the cobaltocenium cation is promising for use in AAEMFC. Two …


Design And Syntheses Of Donor-Acceptor Dyads And Triads For Improved Light Harvesting In Organic Photovoltaics, Andrea Della Pelle Apr 2014

Design And Syntheses Of Donor-Acceptor Dyads And Triads For Improved Light Harvesting In Organic Photovoltaics, Andrea Della Pelle

Doctoral Dissertations

All organic photovoltaics (OPVs) undergo four major processes to convert sunlight in electrical energy. The first process is the absorbance of sunlight. Due to the limit of available acceptor molecules, the burden of light absorbance weighs heavily on the donor material. This thesis focuses heavily on the development of dyes consisting of donor-acceptor dyads and triads for improved light harvesting in OPVs. Squaraine dyes show impressive light harvesting properties with absorbances in the UV to near IR region with extinction coefficients on the order of 105 M--‐1 cm--‐1. Unfortunately, improved light harvesting is not enough to insure optimized OPVs. Energy …