Electronic conductivity and

Flaws in the anodic oxide film are usually the primary source of electronic conduction. These flaws are either stmctural or chemical in nature. The stmctural flaws include thermal crystalline oxide, nitrides, carbides, inclusion of foreign phases, and oxide recrystaUi2ed by an appHed electric field. The roughness of the tantalum surface affects the electronic conduction and should be classified as a stmctural flaw (58) the correlation between electronic conduction and roughness, however, was not observed (59). Chemical impurities arise from metals alloyed with the tantalum, inclusions in the oxide of material from the formation electrolyte, and impurities on the surface of the tantalum substrate that are incorporated in the oxide during formation. 

After briefly introducing the main electronic features of CNTs (Sec. 2) and some general aspects of electronic conduction and transmission (Sec.. 1), we will show how complex electrical measurements to perform on such tiny entities are (Sec. 4). Then we will present the main experimental results obtained on the electrical resistivity of MWCNT and SWCNT and the very recent data relative to the thermopower of SWCNT bundles (Sec. 5). We will also discuss the effect of intercalation on the electrical resistivity of SWCNT bundles (Sec. 6). Finally, we will present some potential applications (Sec. 7). 

In the systems illustrated in Figure 53.1, the anodic reaction has to be electrically balanced by the cathodic reaction, since electrical charge cannot build up at any location. A continuous electrical circuit is required through the metal (for electron conduction) and the environment (for ionic conduction). 

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... 

The brass-colored PdTel consists of Jahn-Teller distorted PdTe2/2l4/4 octahedra, which are interconnected by common edges and corners to afford a loose, spatial network. The compound is considered to be ionic, containing Pd and Te , although the observed diamagnetism, electronic conduction, and color suggest some metallic character. 

The current efficiency may range from 25-30% to as high as 90-100%. The loss in efficiency may be due to several factors which influence the chemical and the electrochemical reactions at the electrodes. For example, factors such as the occurrence of side reactions, the passage of current by electronic conduction, and the dislodging of the deposited product from the electrode may substantially reduce the value of T. In general, the current... 

Note Electronic conductivity, and even superconductivity at ca. 10 K, was observed with a new carbon polymorph, buckminsterfullerene, synthesized in 1990. Electrochemical and photoelectrochemical properties of a semiconducting diamond electrode were studied by Pleskov.)... 

It should be emphasized that the electrochemical carbonization proceeds, in contrast to all other common carbonization reactions (pyrolysis), already at the room temperature. This fact elucidates various surprising physicochemical properties of electrochemical carbon, such as extreme chemical reactivity and adsorption capacity, time-dependent electronic conductivity and optical spectra, as well as its very peculiar structure which actually matches the structure of the starting fluorocarbon chain. The electrochemical carbon is, therefore, obtained primarily in the form of linear polymeric carbon chains (polycumulene, polyyne), generally termed carbyne. This can be schematically depicted by the reaction ... 

The complexes /uo[IrL3X(OH2)], HL = phthalimide, X = bpy, phen, have been prepared and characterized by IR and UV-vis spectroscopy, electronic conductance and magnetic measurements.117... 

Ward DR, Halas NJ, Ciszek JW, Tour JM, Wu Y, Nordlander P, Natelson D (2008) Simultaneous measurements of electronic conduction and Raman response in molecular junctions. Nano Lett 8(3) 919-924... 

Gopel, W. Schierbaum, K.D. Electronic Conductance and Capacitance Sensors. In Sensors A comprehensive Survey. 

In many transition-metal oxides and sulfides, ionic conductivity is augmented by electronic conductivity, and transport numbers need to include contributions from electrons and holes. These mixed conductors are described in Section 8.8. 

Shown in Figure 1.1 is the oxygen ion conductivity of selected oxides. Among these oxides, only a few materials have been developed as SOFC electrolytes due to numerous requirements of the electrolyte components. These requirements include fast ionic transport, negligible electronic conduction, and thermodynamic stability over a wide range of temperature and oxygen partial pressure. In addition, they must... 

A similar infiltration method was used to form anodes with Cu-Co alloys as the electronically conducting phase, with Co added to enhance the anode catalytic activity without catalyzing carbon deposition [85], in contrast with Ni-Cu alloys, which were found to catalyze carbon deposition even when small quantities of Ni were present [86], The authors of the studies [84-86] have reported that the percolation of the infiltrated phases is incomplete following the processing of the cells, such that subsequent carbon deposition can actually serve to connect previously isolated islands of the metallic phase, thus increasing the electronic conductivity and decreasing Rs in the short term. Since carbon deposition was observed by the same authors to cause severe... 

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