Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Properties electronic conductivity

NR-metal composites have many important properties such as non-linear optical properties, electronic conductivity and luminescence, and have been... [Pg.345]

Dielectric properties Electronic conductivity Permeability coefficient... [Pg.235]

AM to woik, even if this does not inherently possess the required properties (electronic conductivity and Li diffusion). [Pg.46]

At low currents, the rate of change of die electrode potential with current is associated with the limiting rate of electron transfer across the phase boundary between the electronically conducting electrode and the ionically conducting solution, and is temied the electron transfer overpotential. The electron transfer rate at a given overpotential has been found to depend on the nature of the species participating in the reaction, and the properties of the electrolyte and the electrode itself (such as, for example, the chemical nature of the metal). [Pg.603]

This article addresses the synthesis, properties, and appHcations of redox dopable electronically conducting polymers and presents an overview of the field, drawing on specific examples to illustrate general concepts. There have been a number of excellent review articles (1—13). Metal particle-filled polymers, where electrical conductivity is the result of percolation of conducting filler particles in an insulating matrix (14) and ionically conducting polymers, where charge-transport is the result of the motion of ions and is thus a problem of mass transport (15), are not discussed. [Pg.35]

The active layer consists of a polymer having electronic conductive, ionic conductive, and luminescent properties, is blended with an ionic salt [48]. The polymer with the required properties can be realized by a blend of a conjugated and an ionic conductive polymer [481 or by specially designed polymers [71-73],... [Pg.156]

Perhaps the first practical application of carbonaceous materials in batteries was demonstrated in 1868 by Georges Le-clanche in cells that bear his name [20]. Coarsely ground MnO, was mixed with an equal volume of retort carbon to form the positive electrode. Carbonaceous powdered materials such as acetylene black and graphite are commonly used to enhance the conductivity of electrodes in alkaline batteries. The particle morphology plays a significant role, particularly when carbon blacks are used in batteries as an electrode additive to enhance the electronic conductivity. One of the most common carbon blacks which is used as an additive to enhance the electronic conductivity of electrodes that contain metal oxides is acetylene black. A detailed discussion on the desirable properties of acetylene black in Leclanche cells is provided by Bregazzi [21], A suitable carbon for this application should have characteristics that include (i) low resistivity in the presence of the electrolyte and active electrode material, (ii) absorption and retention of a significant... [Pg.236]

Composite structures that consist of carbon particles and a polymer or plastic material are useful for bipolar separators or electrode substrates in aqueous batteries. These structures must be impermeable to the electrolyte and electrochemical reactants or products. Furthermore, they must have acceptable electronic conductivity and mechanical properties. The physicochemical properties of carbon blacks, which are commonly used, have a major effect on the desirable properties of the conductive composite structures. Physicochemical properties such as the surface... [Pg.237]

Traditionally, the chemical stability of the electrode/electrolyte interface and its electronic properties have not been given as much consideration as structural aspects of solid electrolytes, in spite of the fact that the proper operation of a battery often depends more on the interface than on the solid electrolyte. Because of the high ionic conductivity in the electrolyte and the high electronic conductivity in the electrode, the voltage falls completely within a very narrow region at the electrolyte/electrode interface. [Pg.538]

Rotations around torsional barriers induce changes in chain conformation. For conjugated systems like polydiacetylenes, flow-induced changes in chain conformation can have a profound influence on the photon absorption and electronic conductivity properties of the material [73]. Flow-induced changes in molecular conformation form the basis for several technically important processes, the best known examples are the production of oriented fibers by gel spinning [74], the compatibility enhancement [75] and the shear-induced modification of polymer morphology [76]. [Pg.103]

Today, the term solid electrolyte or fast ionic conductor or, sometimes, superionic conductor is used to describe solid materials whose conductivity is wholly due to ionic displacement. Mixed conductors exhibit both ionic and electronic conductivity. Solid electrolytes range from hard, refractory materials, such as 8 mol% Y2C>3-stabilized Zr02(YSZ) or sodium fT-AbCb (NaAluOn), to soft proton-exchange polymeric membranes such as Du Pont s Nafion and include compounds that are stoichiometric (Agl), non-stoichiometric (sodium J3"-A12C>3) or doped (YSZ). The preparation, properties, and some applications of solid electrolytes have been discussed in a number of books2 5 and reviews.6,7 The main commercial application of solid electrolytes is in gas sensors.8,9 Another emerging application is in solid oxide fuel cells.4,5,1, n... [Pg.91]

D-TEM gave 3D images of nano-filler dispersion in NR, which clearly indicated aggregates and agglomerates of carbon black leading to a kind of network structure in NR vulcanizates. That is, filled rubbers may have double networks, one of rubber by covalent bonding and the other of nanofiller by physical interaction. The revealed 3D network structure was in conformity with many physical properties, e.g., percolation behavior of electron conductivity. [Pg.544]

Physical properties, such as magnetism and electronic conduction, are largely unexplored for Prl2. This is not because pure Prl2 caimot be made (see 4.2). Rather, that it is extremely difficult, if not impossible, to produce single-phase, i.e., one-modification samples on a scale sufficiently large for these measure-... [Pg.51]

Fig. 2 shows the temperature as a function of irradiation time of Cu based material under microwave irradiation. CuO reached 792 K, whereas La2Cu04, CuTa20e and Cu-MOR gave only 325, 299 and 312 K, respectively. The performances of the perovskite type oxides were not very significant compared to the expectation from the paper reported by Will et al. [5]. This is probably because we used a single mode microwave oven whereas Will et al. employed multi-mode one. The multi-mode microwave oven is sometimes not very sensitive to sample s physical properties, such as electronic conductivity, crystal sizes. From the results by electric fixmace heating in Fig. 1, at least 400 K is necessary for NH3 removal. So, CuO was employed in the further experiments although other materials still reserve the possibility as active catalysts when we employ a multi-mode microwave oven. [Pg.311]


See other pages where Properties electronic conductivity is mentioned: [Pg.51]    [Pg.48]    [Pg.329]    [Pg.580]    [Pg.554]    [Pg.840]    [Pg.51]    [Pg.524]    [Pg.80]    [Pg.428]    [Pg.1048]    [Pg.974]    [Pg.424]    [Pg.498]    [Pg.899]    [Pg.51]    [Pg.48]    [Pg.329]    [Pg.580]    [Pg.554]    [Pg.840]    [Pg.51]    [Pg.524]    [Pg.80]    [Pg.428]    [Pg.1048]    [Pg.974]    [Pg.424]    [Pg.498]    [Pg.899]    [Pg.429]    [Pg.207]    [Pg.237]    [Pg.289]    [Pg.535]    [Pg.345]    [Pg.35]    [Pg.40]    [Pg.44]    [Pg.208]    [Pg.89]    [Pg.331]    [Pg.28]    [Pg.234]    [Pg.243]    [Pg.609]    [Pg.69]    [Pg.575]    [Pg.617]    [Pg.34]    [Pg.401]    [Pg.635]   
See also in sourсe #XX -- [ Pg.221 , Pg.225 , Pg.227 , Pg.228 ]




SEARCH



Conductance electronic

Conducting electrons

Conducting properties

Conduction electrons

Conductivity: electronic

Electron conductance

Electron conductivity

Electronic Structures and Conduction Properties of Biopolymers

Electronic conduction

Electronically conducting

Electronics conduction

Properties conductivity

© 2024 chempedia.info