Physical Sciences and Mathematics Commons^™

A New Method In The Synthesis Of Conductive Polymers; Synthesis, Characterization, And Investigation Of Photocatalytic Properties Of Polyaniline, Muzaffer Can

Turkish Journal of Chemistry

As known, in the synthesis of conductive polyaniline polymer from aniline monomer, the polymerization medium must be acidic. In order to make the polymerization medium acidic, protonic acids such as HCl and H2SO4 are generally used. In this study, two acids have been used to make the polymerization medium acidic. One of them, as we know, is H2SO4 as a protonic acid. The other acid is the zinc ion, which is a Lewis acid. The metal ion has never been used for this purpose up to now. Two polyaniline polymers have been synthesized to prove that conductive polymers can also …

Nitro-Aromatic Polymers For Conversion-Style Battery Cathodic Materials, Brady P. Samuelson

Honors Thesis

The development of organic electrode materials in rechargeable batteries has seen a resurgence in recent decades. This spike in interest is mostly due to the increased investments in renewable energy sources, grid-scale energy storage, and the rapid transition to electric vehicles. Current lithium battery cathode materials typically use some form of lithium metal oxide (specific capacity: 272 mAh g^-1 which has problems with limited capacity, thermal runaway, and an unreliable supply chain. Our research group’s solution involves investigating new lightweight, organic redox groups combined with a conductive polymer backbone to serve as a possible replacement for the cathode in …

Synthesis And Characterization Of An Electrochromic Copolymer Based On 9, 10-Di (Furan-2-Yl)Anthracene And 3,4-Ethylenedioxythiophene, Ali̇ Kalçik, Ari̇f Kivrak, Buket Çarbaş

Turkish Journal of Chemistry

In this study, a new copolymer, which is a combination of two chemical structure (9,10-di(furan-2-yl)anthracene and 3,4-ethylenedioxythiophene was synthesized via electrochemical synthesis methods in the electrolyte medium of 0.1 M TBAPF6/ ACN solution. PEDOT homopolymer was also electrosynthesized for comparator experiments of the polymer formations in the same medium. The characterizations of polymers were achieved with general optical and electrochemical characterization techniques. The corresponding electrochromic copolymer shows blue and lilac color in its neutral and oxidized states, respectively. The copolymer has an optical band gap of 1.65 eV and 24% optical contrast at 500 nm with a high coloration efficiency …

A New Electrochromic Copolymer Composed Of 4,7-Di(Thiophen-2-Yl)Benzo[C] [1,2,5] Thiadiazole And 3,4-Ethylenedioxythiophene, Kübra Çeli̇k, Ari̇f Kivrak, Buket Çarbaş

Turkish Journal of Chemistry

A new electrochromic copolymer based on 4,7-di(thiophen-2-yl)benzo[c] [1,2,5]thiadiazole and 3,4-ethylenedioxythiophene was successfully obtained via the electrochemical polymerization method in the medium of electrolyte solution, which consists of 0.1 M tetrabutylammonium hexafluorophosphate and dichloromethane. In order to compare the electrochemical and chemical properties of the copolymer, the benzothiodiazole derivative and 3,4-ethylenedioxythiophene (EDOT) monomers, which are parts of the copolymer, are electrochemically polymerized, separately in the same environment and concentration with the copolymer. Poly(4,7-di(thiophen- 2-yl)benzo[c][1,2,5]thiadiazole) (P(TBT)) and poly(3,4-ethylenedioxythiophene) (PEDOT) polymers were obtained. Before starting the electrochemical synthesis, the initial oxidation potentials of the monomers that form the copolymer were compared via the …

Metal Salt Hydrolysis For Electrochemically Active Conducting Polymer Nanocomposites, Hongmin Wang

Arts & Sciences Electronic Theses and Dissertations

The diversity of nanostructures obtained from organic polymerization is limited when compared to the vast amount of inorganic nanostructures. This dissertation will focus on a synergistic mechanism between organic polymerization and in situ inorganic salt hydrolysis for developing electrochemically active organic-inorganic hybrid nanostructures. The degree of polymerization, crystallinity and doping level of the conjugated polymer backbone is controlled using oxidative radical vapor-phase polymerization resulting in organic semiconductors featuring high crystallinity and superior electrical conductivity. An aqueous metal salt solution of iron (III) chloride serves as an oxidant for initiating the polymerization and interestingly, this inorganic salt hydrolyzes in situ producing …

Self-Assembly Of Conducting Polymer Nano- And Microstructures For Energy Storage, Luciano Matteo Santino

Arts & Sciences Electronic Theses and Dissertations

Plastics are materials composed of many long chains of molecules with repeating subunits; strong interactions between neighboring molecules lead to the material used throughout the world. Plastics are commonly thought to be insulating, in stark contrast to the conductivity of metals. However, certain polymer structures were discovered to exhibit semiconducting properties, the subject of the Nobel Prize in Chemistry in 2000. Conducting polymers have a unique molecular structure with an electronically conjugated backbone, allowing electrons to freely travel both across the chain and in between chains. This work focuses on controlling the kinetics of the reaction between the vapors of …

Frequency-Dependent Photothermal Measurement Of Thermal Diffusivity For Opaque And Non-Opaque Materials: Application To Crystals Of Tips-Pentacene, Maryam Shahi, Joseph W. Brill

Physics and Astronomy Faculty Publications

We propose the use of a frequency-dependent photothermal measurement as a complement to light-flash, i.e., time-dependent, measurements to determine the through-plane thermal diffusivity of small, thin samples, e.g., semiconducting polymers and small organic molecule crystals. The analysis is extended from its previous use with some opaque conducting polymers to materials with finite absorption coefficients, such as crystals of 6,13-bis(triisopropylsilylethynyl)pentacene. Taking into account the finite absorption coefficients of the latter gives a value of diffusivity, D ≈ 0.10 mm²/s, much smaller than previously estimated and more consistent with its expected value. We also briefly discuss the effects of coating …

Preparation And Characterization Of Polyaniline Microrods Synthesized By Using Dodecylbenzene Sulfonic Acid And Periodic Acid, Recep Taş, Muzaffer Can, Savaş Sönmezoğlu

Turkish Journal of Chemistry

The preparation of polyaniline (PANI) microrod arrays in the presence of dodecylbenzene sulfonic acid (DBSAH), a structure-directing agent, and in the presence of periodic acid (H$_{5}$IO$_{6})$, an oxidant in aqua-acidic media, was investigated. DBSAH was performed to distinguish the roles of both surfactant and dopant. The method of preparation of DBSAH and H$_{5}$IO$_{6}$ doped PANI (DBSAH-PANI) microrods in a reversed micelle had previously not been reported. The characterizations of the PANI microrods were determined by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy, (EDX) and X-ray diffraction (XRD). Based on the SEM results, we found that PANI microrods occur in …

Applied Analysis Of Ionic Polymer Metal-Composite Actuators, Siul Ruiz, Benjamin Mead, Woosoon Yim

College of Engineering: Graduate Celebration Programs

• IPMC is a type of smart material called an electroactive polymer
• Consists of an ionic polymer such as Nafion or Flemion and a conducive metal such as platinum or gold
• COMSOL multi-physics simulations accurately model the experimental displacement results
• Optimization performed using the multi-physics model to find the maximum deflection, force, and twisting
• Using the closed loop control system accurate IPMC tip location can be achieved
• This control system has been extended to function using a computer mouse as an input

Removal Of Cr(Iii) And Cu(Ii) Using Oly(2-Chloroaniline)/Polyvinylidenefluoride Composite Cation-Exchange Membranes By Donnan Dialysis, Esengül Kir, Sabri̇ye Perçi̇n Özkorucuklu, Tuğba Sardohan Köseoğlu, Esi̇n Karamizrak

Turkish Journal of Chemistry

P2ClAn/PVDF composite membranes were prepared utilizing cation-exchange groups in the PVDF (polyvinylidenefluoride) membrane matrix by casting method. The poly(2-chloroaniline) (P2ClAn) was chemically synthesized with different dopant anions such as o-aminobenzene sulfonic acid (ABS) and sodium dodecyl sulfate (SDS). P2ClAn/PVDF membranes were extensively characterized for their surface morphology, thickness, ion-exchange capacity, SEM, AFM, and FTIR-ATR measurements. The SEM, AFM and FTIR-ATR pictures, comparing the original PVDF membrane support sheet to P2ClAn/PVDF composite membranes, indicate that the morphologies of the membranes are different. The membrane potential measurements were performed in various electrolyte solutions in order to observe the selectivity and stability of …

Electrochemical Performance Of Screen-Printed Composite Coatings Of Conducting Polymers And Carbon Nanotubes On Titanium Bipolar Plates In Aqueous Asymmetrical Supercapacitors, Xiaohang Zhou, George Z. Chen

Journal of Electrochemistry

Composites of conducting polymers (polypyrrole and polyaniline) with acid treated multi-walled carbon nanotubes were formulated into printable aqueous inks, with the aid of functional additives (benzethonium chloride as a surfactant with or without polyvinyl alcohol as a binder). The inks were screen-printed as fairly uniform coatings of various mass loading densities and areas (up to 75 mg cm^-2 and 100 cm²) on thin titanium plates (0.1 mm in thickness). These screen-printed plates were used to fabricate both unit cell and multi-cell stack of asymmetrical supercapacitors with screen-printed negative electrodes of activated carbon (pigment black) in aqueous electrolytes …

Infraded Surface Plasmon Polaritons On Semiconductor, Semimetal And Conducting Polymer, Monas Shahzad

Electronic Theses and Dissertations

Conductors with IR (infrared) plasma frequencies are potentially useful hosts of surface plasmon polaritons (SPPs) with subwavelength mode confinement for sensing applications. The underlying aim of this work is to identify such conductors that also have sharp SPP excitation resonances for biosensor applications at infrared (3-11 m) wavelengths, where biological analytes are strongly differentiated by their IR absorption spectra. In this work, various materials were investigated such as a heavily doped semiconductor, a semimetal, a conducting polymer and its composite. Heavily doped silicon was investigated by tuning its plasma frequency to the infrared region by heavily doping. The measured complex …

Electrochemistry Of Pani/Metal Composites In Basic Solutions, Tamthinhan Quy

UNLV Theses, Dissertations, Professional Papers, and Capstones

Polyaniline (PANI) has been extensively investigated due to its unique conductivity, which is primarily dependent on the oxidation state of the material and the solution pH. PANI is an insulator when it is oxidized, and the solution pH exceeds four. Numerous attempts to extend PANI's conductivity to neutral and alkaline environments have been unsuccessful. However, our previous study has demonstrated that PANI/Pd composite is conductive and catalytically active in a basic solution, pH ∼ 12. Therefore, the conductivity and the electrochemical properties of PANI composites including PANI/Au, PANI/Pd and PANI/Pt were evaluated in basic solutions. The fundamental studies of PANI/metal …

Physical And Electrical Characterization Of Triethanolamine Based Sensors For No₂ Detection And The Influence Of Humidity On Sensing Response, Zachariah Marcus Peterson

Dissertations and Theses

Triethanolamine (TEA) is a semiconducting polymer which exhibits a resistance change when exposed to various gases. The polymer also exhibits a number of reactions with nitrogen dioxide, with the reaction products being heavily dependent on the presence or absence of water vapor. Previous studies have attempted the incorporation of a TEA-carbon nanoparticle composite as the active sensing layer in a chemresistive sensor for detection of NO₂. The incorporation of carbon nanoparticles in the polymer nanocomposite was thought to amplify the sensor's response. There are a number of chemical reactions that can occur between TEA and NO₂, with the reaction products …

Novel Π-Conjugated Materials Plus Their Characterizations And Applications, Xiuxian He

All Dissertations

The theme of this dissertation will focus on the syntheses and characterization of bipyridine (bipy) containing π-conjugated polymers (CPs). Specifically, poly(p-phenylene ethynylene), polyfluorene and poly(p-phenylene vinylene) derivatives have been prepared via Sonogashira coupling, Suzuki coupling and Heck coupling, respectively. Derivatives of poly(p-phenylene ethynylene), polyfluorene and poly(p-phenylene vinylene) are known to have applications in optical and electronic devices. Through this study, polymers condensed with bulky bipy-containing TAB as one of the copolymer units have shown increased solubility and diminished intrachain/interchain aggregation in solution and in film due to the effectiveness of TAB in controlling the relative orientations of individual polymer chains. …

Electrochemical And Optical Properties Of An Azo Dye Based Conducting Copolymer, Ati̇lla Ci̇haner, Fati̇h Algi

Turkish Journal of Chemistry

The electrochemical and optical properties of a novel conducting copolymer called poly(2,5'-dimethyl-[4-(2,5-di-thiophen- 2-yl-pyrrol-1-yl)-phenyl]azobenzene-co-(3,4-ethylenedioxythiophene)) (poly(1-co-EDOT)) are reported. Electrochemically synthesized poly(1-co-EDOT) based on the azo dye has a well-defined and reversible redox couple (0.37 V vs. Ag/AgCl) with good cycle stability. The copolymer film exhibits high conductivity (13 S/cm) as well as electrochromic behavior (magenta when neutralized and transmissive sky blue when oxidized). Furthermore, electro-optically active copolymer film has a low band gap of 1.79 eV with a \pi-\pi* transition at 555 nm.

Temperature And Electric Field Dependence Of Conduction In Low-Density Polyethylene, John R. Dennison, Jerilyn Brunson

All Physics Faculty Publications

A traditional constant voltage conductivity test method was used to measure how the conductivity of highly insulating low-density polyethylene (LDPE) polymer films depends on applied electric field, repeated and prolonged electric field exposure, and sample temperature. The strength of the applied voltage was varied to determine the electric field dependence. At low electric field, the resistivity was measured from cryogenic temperatures to well above the glass transition temperature. Comparisons were made with a variety of models of the conduction mechanisms common in insulators, including transient polarization and diffusion and steady-state thermally activated hopping conductivity and variable range hopping conductivity, to …

Nanostructered Aminophenylporphyrin Films For Use In Bulk Heterojunction And Inverse Dye-Sensitized Tio₂ Solar Cells, Michael George Walter

Dissertations and Theses

Conductive nanostructured films of poly-tetrakis-5,10,15,20-(4-aminophenyl)porphyrin (TAPP) can be grown electrochemically or through interfacial oxidative polymerization. The poly-TAPP nanomorphology is sensitive to the electrochemical solvent, potentiometric method, and the aminophenyl porphyrin monomer utilized. To elucidate the molecular structure of poly-TAPP and to correlate structures with proposed polymerization and conductivity mechanisms, reflectance FT-IR and spectroelectrochemistry were used to detect the presence and electroactivity of dihydrophenazine and phenazine polymer linkages formed during the polymerization.

Poly-TAPP nanofiber films were evaluated for use in a bulk heterojunction solar cell (with PCBM) and in an inverse dye-sensitized TiO2 solar cell using the poly-TAPP nanoporous scaffold to …

Conducting Polymer-Carbon Nanotubes Composites, May Tahhan, N. Barisci, Gordon G. Wallace

Gordon Wallace

During the course of this work, three different approaches to the formation of conducting polymer/carbon nanotube (CP/CNT) composites were investigated. The first approach involved the preparation of CNT dispersions using Poly methoxy aniline-5-sulfonic acid (PMAS) as a stabilizer. The second approach investigated involved the use of CNT as the dopant in the electropolymerization of CPs. The third approach involved the electrochemical deposition of a thin polymer film onto the surface of CNT paper. These CNT/CP composites were characterized to determine capacitance, conductivity and mechanical strength.

Chemomechanical Polymers As Sensors And Actuators For Biological And Medicinal Applications, Hans-Jörg Schneider, Kazuaki Kato, Robert M. Strongin

Chemistry Faculty Publications and Presentations

Changes in the chemical environment can trigger large motions in chemomechanical polymers. The unique feature of such intelligent materials, mostly in the form of hydrogels, is therefore, that they serve as sensors and actuators at the same time, and do not require any measuring devices, transducers or power supplies. Until recently the most often used of these materials responded to changes in pH. Chemists are now increasingly using supramolecular recognition sites in materials, which are covalently bound to the polymer backbone. This allows one to use a nearly unlimited variety of guest (or effector) compounds in the environment for a …

Structural Characterization Of Poly(Heterocycles) Formed Using Oxidative Methods, Rebecca Marie Brauch

LSU Doctoral Dissertations

This research focused on elucidation of structural information for conducting polymer systems using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). The structure of conducting polymer systems has been found to directly influence their physical properties. Poly(pyrrole) and poly(thiophene) are two of the most widely studied conducting polymers due to their high electrical conductivity, stability in the doped state, low toxicity, and current/potential applications. The purpose of this research was to apply MALDI-TOF MS to heterocyclic conducting polymers, specifically those of pyrrole and thiophene, to investigate structural properties of these polymers, with the specific aim of determining end group and …

Studies On The Electrochemical Preparation And Electrochemical Properties Of Conducting Polymers——Brief Introduction To The Research Work Of Electrochemistry Of Conducting Polymers In Cas Key Laboratory Of Organic Solids(I), Yong-Fange Academy Of Sciences Li

Journal of Electrochemistry

Conducting polymers have drawn much attention since the discovery of conducting polyacetylene in 1977, due to the novelty and curiosity of their structure and properties as well as their promising applications in many aspects. Among the studies of conducting polymers, the electrochemical preparation and electrochemical properties of conducting polymers are of special importance, because the electropolymerization is a main method for preparing conducting polymer films and the electrochemical properties are the basis for their applications in the fields of electrode materials for batteries, electrocatalysis, electrochromic display, etc. We are one of the earliest research groups in the world to perform …

Preparation And Characterization Of Conducting Polybutadiene/ Polythiophene Composites, Senem Kiralp, Zuhal Küçükyavuz, Atef F. Qasrawi

Turkish Journal of Chemistry

Conductive composite films of cis-1,4-polybutadiene (PBD) with polythiophene (PTh) were prepared electrochemically. Thiophene was polymerized on PBD-coated platinium electrodes. The composites with different PTh percentages showed conductivity in the order of 10^{-3} (\Omega cm)^{-1}. The characterization of the films was performed using FTIR, scanning electron microscope and differential scanning calorimetry techniques. In order to understand the dominant transport mechanism, the temperature dependence of conductivity was investigated.

Conducting Polymer-Carbon Nanotubes Composites, May Tahhan, N. Barisci, Gordon G. Wallace

Faculty of Science - Papers (Archive)

During the course of this work, three different approaches to the formation of conducting polymer/carbon nanotube (CP/CNT) composites were investigated. The first approach involved the preparation of CNT dispersions using Poly methoxy aniline-5-sulfonic acid (PMAS) as a stabilizer. The second approach investigated involved the use of CNT as the dopant in the electropolymerization of CPs. The third approach involved the electrochemical deposition of a thin polymer film onto the surface of CNT paper. These CNT/CP composites were characterized to determine capacitance, conductivity and mechanical strength.