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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 conducted ... [...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 Electrical conductance, conduct electricity. Such compounds may have metallic conductivity or can be semiconductors. The biggest advantage of conductive polymers is their processability, mainly by Dispersion (chemistry), 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 reduced form was colourless but the oxidized forms were ... [...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. The rings are linked through the 2- and 5-positions. Poly(alkylthiophene)s have Alkyl, 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, temperature, Electric potential, applied potential, and binding to other molecules. Changes in both color and conductivity are induced by the same mechanism, tw ... [...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 peroxy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solution (chemistry)
In chemistry, a solution is a special type of homogeneous mixture composed of two or more substances. In such a mixture, a solute is a substance dissolved in another substance, known as a solvent. If the attractive forces between the solvent and solute particles are greater than the attractive forces holding the solute particles together, the solvent particles pull the solute particles apart and surround them. These surrounded solute particles then move away from the solid solute and out into the solution. The mixing process of a solution happens at a scale where the effects of chemical polarity are involved, resulting in interactions that are specific to solvation. The solution usually has the state of the solvent when the solvent is the larger fraction of the mixture, as is commonly the case. 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Semiconductors
Organic semiconductors are solids whose building blocks are pi-bonded molecules or polymers made up by carbon and hydrogen atoms and – at times – heteroatoms such as nitrogen, sulfur and oxygen. They exist in the form of molecular crystals or amorphous thin films. In general, they are electrical insulators, but become semiconducting when charges are either injected from appropriate electrodes, upon doping or by photoexcitation. General properties In molecular crystals the energetic separation between the top of the valence band and the bottom conduction band, i.e. the band gap, is typically 2.5–4 eV, while in inorganic semiconductors the band gaps are typically 1–2 eV. This implies that they are, in fact, insulators rather than semiconductors in the conventional sense. They become semiconducting only when charge carriers are either injected from the electrodes or generated by intentional or unintentional doping. Charge carriers can also be generated in the cours ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Polymers
A polymer (; Greek '' poly-'', "many" + '' -mer'', "part") is a substance or material consisting of very large molecules called macromolecules, composed of many repeating subunits. Due to their broad spectrum of properties, both synthetic and natural polymers play essential and ubiquitous roles in everyday life. Polymers range from familiar synthetic plastics such as polystyrene to natural biopolymers such as DNA and proteins that are fundamental to biological structure and function. Polymers, both natural and synthetic, are created via polymerization of many small molecules, known as monomers. Their consequently large molecular mass, relative to small molecule compounds, produces unique physical properties including toughness, high elasticity, viscoelasticity, and a tendency to form amorphous and semicrystalline structures rather than crystals. The term "polymer" derives from the Greek word πολύς (''polus'', meaning "many, much") and μέρος (''meros'', meaning "p ... [...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 2021 impact factor of 6.065. See also * ''New Journal of Chemistry'' * ''Chemical Society Reviews'' * ''Chemical Science'' * ''RSC Advances ''RSC Advances'' is an online ... [...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 deter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photovoltaic
Photovoltaics (PV) is the conversion of light into electricity using semiconducting materials that exhibit the photovoltaic effect, a phenomenon studied in physics, photochemistry, and electrochemistry. The photovoltaic effect is commercially used for electricity generation and as photosensors. A photovoltaic system employs solar modules, each comprising a number of solar cells, which generate electrical power. PV installations may be ground-mounted, rooftop-mounted, wall-mounted or floating. The mount may be fixed or use a solar tracker to follow the sun across the sky. Photovoltaic technology helps to mitigate climate change because it emits much less carbon dioxide than fossil fuels. Solar PV has specific advantages as an energy source: once installed, its operation generates no pollution and no greenhouse gas emissions, it shows scalability in respect of power needs and silicon has large availability in the Earth's crust, although other materials required in PV system man ... [...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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electrochromism
Electrochromism is a phenomenon in which a material displays changes in color or opacity in response to an electrical stimulus. In this way, a smart window made of an electrochromic material can block specific wavelengths of ultraviolet, visible or (near) infrared light. The ability to control transmittance of near infrared light can increase the 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 need only 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 where it is used to automatically tint rear-view mirrors in various lighting conditions. Principle The phenomenon of electrochromism occurs in some transition metal oxides which conduct both electricity and ions, such as tungsten trioxide (WO3). ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
