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Poly(3,4-ethylenedioxythiophene)
Poly(3,4-ethylenedioxythiophene) (PEDOT or PEDT; ''IUPAC'' name poly(2,3-dihydrothieno ,4-''b''1,4]dioxane-5,7-diyl)) is a conducting polymer based on 3,4-ethylenedioxythiophene or EDOT. It was first reported by Bayer AG in 1989. Polymer PEDOT possesses many advantageous properties compared to earlier conducting polythiophenes like 3-alkylthiophenes. For example, the polymer is optically transparent in its conducting state and has high stability, moderate band gap, and low redox potential. Its major disadvantage is its poor solubility, which is partly circumvented by use of composite materials such as PEDOT:PSS and PEDOT-TMA. The polymer is generated by oxidation. The process begins with production of the radical cation of EDOT monomer, 2H4O2C4H2Ssup>+. This cation adds to a neutral EDOT followed by deprotonation. The idealized conversion using peroxydisulfate is shown: :n C2H4O2C4H2S + n (OSO3)22− → 2H4O2C4Ssub>n + 2n HOSO3− Polymerization is usually condu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PEDOT
Poly(3,4-ethylenedioxythiophene) (PEDOT or PEDT; ''IUPAC'' name poly(2,3-dihydrothieno[3,4-''b''][1,4]dioxane-5,7-diyl)) is a conducting polymer based on 3,4-Ethylenedioxythiophene, 3,4-ethylenedioxythiophene or EDOT. It was first reported by Bayer AG in 1989. Polymer PEDOT possesses many advantageous properties compared to earlier conducting polythiophenes like Polythiophene#3-Alkylthiophenes, 3-alkylthiophenes. For example, the polymer is Transparency (optics), optically transparent in its electrical conduction, conducting state and has high stability, moderate band gap, and low oxidation potential, redox potential. Its major disadvantage is its poor solubility, which is partly circumvented by use of composite materials such as PEDOT:PSS and PEDOT-TMA. The polymer is generated by oxidation. The process begins with production of the radical cation of EDOT monomer, [C2H4O2C4H2S]+. This cation adds to a neutral EDOT followed by deprotonation. The idealized conversion using perox ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PEDOT-TMA
Poly(3,4-ethylenedioxythiophene)-tetramethacrylate or PEDOT-TMA is a p-type conducting polymer based on 3,4-ethylenedioxylthiophene or the EDOT monomer. It is a modification of the PEDOT structure. Advantages of this polymer relative to PEDOT (or PEDOT:PSS) are that it is dispersible in organic solvents, and it is non-corrosive. PEDOT-TMA was developed under a contract with the National Science Foundation, and it was first announced publicly on April 12, 2004. The trade name for PEDOT-TMA is Oligotron. PEDOT-TMA was featured in an article entitled "Next Stretch for Plastic Electronics" that appeared in Scientific American in 2004. The U.S. Patent office issued a patent protecting PEDOT-TMA on April 22, 2008. PEDOT-TMA differs from the parent polymer PEDOT in that it is capped on both ends of the polymer. This limits the chain-length of the polymer, making it more soluble in organic solvents than PEDOT. The methacrylate groups on the two end-caps allow further chemistry to occ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conducting Polymer
Conductive polymers or, more precisely, intrinsically conducting polymers (ICPs) are organic polymers that conduct electricity. Such compounds may have metallic conductivity or can be semiconductors. The main advantage of conductive polymers is that they are easy to process, mainly by dispersion. Conductive polymers are generally not thermoplastics, ''i.e.'', they are not thermoformable. But, like insulating polymers, they are organic materials. They can offer high electrical conductivity but do not show similar mechanical properties to other commercially available polymers. The electrical properties can be fine-tuned using the methods of organic synthesis and by advanced dispersion techniques. History Polyaniline was first described in the mid-19th century by Henry Letheby, who investigated the electrochemical and chemical oxidation products of aniline in acidic media. He noted that the reduced form was colourless but the oxidized forms were deep blue. The first highly-conduc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polythiophene
Polythiophenes (PTs) are polymerized thiophenes, a sulfur heterocyclic compound, heterocycle. The parent PT is an insoluble colored solid with the formula (C4H2S)n.Strictly speaking, "polythiophene" is a misnomer, since the polymer consists of thienylene (2,5-C4H2S) repeat units. Similarly, thiophene is not a monomer as such. The rings are linked through the 2- and 5-positions. Poly(alkylthiophene)s have alkyl substituents at the 3- or 4-position(s). They are also colored solids, but tend to be soluble in organic solvents. PTs become Conductive polymer, conductive when oxidized. The electrical resistivity and conductivity, electrical conductivity results from the Delocalized electron, delocalization of electrons along the polymer backbone. Conductivity however is not the only interesting property resulting from electron delocalization. The optical properties of these materials respond to environmental stimuli, with dramatic color shifts in response to changes in solvent, t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Communications
''ChemComm'' (or ''Chemical Communications''), formerly known as ''Journal of the Chemical Society D: Chemical Communications'' (1969–1971), ''Journal of the Chemical Society, Chemical Communications'' (1972–1995), is a peer-reviewed scientific journal published by the Royal Society of Chemistry. It covers all aspects of chemistry. In January 2012, the journal moved to publishing 100 issues per year. The current chair of the editorial board is Douglas Stephan (University of Toronto, Canada), while the executive editor is Richard Kelly. Abstracting and indexing The journal is abstracted and indexed in: * Chemical Abstracts * Science Citation Index * Current Contents/Physical, Chemical & Earth Sciences * Scopus * Index Medicus/MEDLINE/PubMed According to the ''Journal Citation Reports'', the journal has a 2023 impact factor of 4.3. See also * '' New Journal of Chemistry'' * ''Chemical Society Reviews ''Chemical Society Reviews'' is a biweekly peer-reviewed scientific journa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
UCLA
The University of California, Los Angeles (UCLA) is a public land-grant research university in Los Angeles, California, United States. Its academic roots were established in 1881 as a normal school then known as the southern branch of the California State Normal School which later evolved into San José State University. The branch was transferred to the University of California to become the Southern Branch of the University of California in 1919, making it the second-oldest of the ten-campus University of California system after the University of California, Berkeley. UCLA offers 337 undergraduate and graduate degree programs in a range of disciplines, enrolling about 31,600 undergraduate and 14,300 graduate and professional students annually. It received 174,914 undergraduate applications for Fall 2022, including transfers, the most of any university in the United States. The university is organized into the College of Letters and Science and twelve professional schoo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Supercapacitors
alt=Supercapacitor, upright=1.5, Schematic illustration of a supercapacitor upright=1.5, A diagram that shows a hierarchical classification of supercapacitors and capacitors of related types A supercapacitor (SC), also called an ultracapacitor, is a high-capacity capacitor, with a capacitance value much higher than solid-state capacitors but with lower voltage limits. It bridges the gap between electrolytic capacitors and rechargeable batteries. It typically stores 10 to 100 times more energy per unit volume or mass than electrolytic capacitors, can accept and deliver charge much faster than batteries, and tolerates many more charge and discharge cycles than rechargeable batteries. Unlike ordinary capacitors, supercapacitors do not use the conventional solid dielectric, but rather, they use electrostatic double-layer capacitance and electrochemical pseudocapacitance, both of which contribute to the total energy storage of the capacitor. Supercapacitors are used in applicati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biocompatible
Biocompatibility is related to the behavior of biomaterials in various contexts. The term refers to the ability of a material to perform with an appropriate host response in a specific situation. The ambiguity of the term reflects the ongoing development of insights into how biomaterials interact with the human body and eventually how those interactions determine the clinical success of a medical device (such as pacemaker, hip replacement or stent). Modern medical devices and prostheses are often made of more than one material so it might not always be sufficient to talk about the biocompatibility of a specific material. Since the immune response and repair functions in the body are so complicated it is not adequate to describe the biocompatibility of a single material in relation to a single cell type or tissue. Sometimes one hears of biocompatibility testing that is a large battery of in vitro test that is used in accordance with ISO 10993 (or other similar standards) to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solution (chemistry)
In chemistry, a solution is defined by IUPAC as "A liquid or solid phase containing more than one substance, when for convenience one (or more) substance, which is called the solvent, is treated differently from the other substances, which are called solutes. When, as is often but not necessarily the case, the sum of the mole fractions of solutes is small compared with unity, the solution is called a dilute solution. A superscript attached to the ∞ symbol for a property of a solution denotes the property in the limit of infinite dilution." One important parameter of a solution is the concentration, which is a measure of the amount of solute in a given amount of solution or solvent. The term " aqueous solution" is used when one of the solvents is water. Types ''Homogeneous'' means that the components of the mixture form a single phase. ''Heterogeneous'' means that the components of the mixture are of different phase. The properties of the mixture (such as concentration, temp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antistatic
An antistatic agent is a compound used for treatment of materials or their surfaces in order to reduce or eliminate buildup of static electricity. Static charge may be generated by the triboelectric effect or by a non-contact process using a high voltage power source. Static charge may be introduced on a surface as part of an in-mold label printing process. The role of an antistatic agent is to make the surface or the material itself slightly conductive, either by being conductive itself, or by absorbing moisture from the air; therefore, some humectants can be used. The molecules of an antistatic agent often have both hydrophilic and hydrophobic areas, similar to those of a surfactant; the hydrophobic side interacts with the surface of the material, while the hydrophilic side interacts with the air moisture and binds the water molecules. Internal antistatic agents are designed to be mixed directly into the material, external antistatic agents are applied to the surface. Common a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electrochromism
Electrochromism is a phenomenon in which a material displays changes in color or Opacity (optics), opacity in response to an voltage, electrical stimulus. In this way, a smart window made of an electrochromic material can block specific wavelengths of ultraviolet, visible light, visible or (near) infrared light. The ability to control the transmittance of near-infrared light can increase the efficient energy use, energy efficiency of a building, reducing the amount of energy needed to cool during summer and heat during winter. As the color change is persistent and energy needs only to be applied to effect a change, electrochromic materials are used to control the amount of light and heat allowed to pass through a surface, most commonly "smart windows". One popular application is in the automobile Industry (economics), industry where it is used to automatically Window film, tint rear-view mirrors in various lighting conditions. Principle The phenomenon of electrochromism occurs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indium Tin Oxide
Indium tin oxide (ITO) is a ternary composition of indium, tin and oxygen in varying proportions. Depending on the oxygen content, it can be described as either a ceramic or an alloy. Indium tin oxide is typically encountered as an oxygen-saturated composition with a formulation of 74% In, 8% Sn, and 18% O by weight. Oxygen-saturated compositions are so typical that unsaturated compositions are termed ''oxygen-deficient ITO''. It is transparent and colorless in thin layers, while in bulk form it is yellowish to gray. In the infrared region of the spectrum it acts as a metal-like mirror. Indium tin oxide is one of the most widely used transparent conducting oxides, not just for its electrical conductivity and optical transparency, but also for the ease with which it can be deposited as a thin film, as well as its chemical resistance to moisture. As with all transparent conducting films, a compromise must be made between conductivity and transparency, since increasing the thickness a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
