Graphite, conductivity

In view of its inertness Pt is mostly used, but it should be borne in mind that in the presence of strongly reducing agents such as Cr(II), Ti(IH) and V(IV) Pt can catalyse the reduction of H+ ions and then does not satisfy the aim of electrode inertness. Under certain conditions one can use electrodes of Pd, Au, graphite, conducting glass or glassy carbon. 

Both benzene and graphite contain delocalised electrons. Why does graphite conduct electricity, yet benzene does not ... 

FIGURE 14.34 Graphite consists of flat planes of hexagons lying above one another. When impurities are present, the planes can slide over one another quite easily. Graphite conducts electricity well within the planes but less well perpendicular to the planes. 

Graphite has layers of hexagonal networks. Each C atom is bonded to three C atoms in the same plane (sp2 hybrids). There is one electron per C in delocalized tt orbitals extending throughout the layer or, in terms of the valence bond theory, there are alternating single and double bonds. Graphite conducts electricity within the plane and can be used as an electrode. 

Effect of Carbon Black and Graphite Conductive Additives on the Electrode Parameters... 

In addition to the beneficial effect on the electrochemical performance, the graphite conductive additives influence the electrode density positively. Typically, the graphitized mesocarbon or... 

Table 1. Specific theoretical capacities for graphite, conducting polymers, and some quinones. ...

Very high m.p.. b.p. Insoluble in water. Graphite conducts, diamond does not. 

The question of whether graphite or carbon black should be preferred as conductive carbon is badly posed. Graphite and carbon blacks show rather complementary properties. The decision of which carbon type should be selected basically depends on the cell requirements and the type of active electrode materials used in the electrodes. Figure 5.20 compares the morphology of a typical carbon black and graphite conductive additive and illustrates the dimensional differences of the primary particles of a factor of about 10. The smaller particle sizes of the carbon black... 

Condias (DIACHEM ), http //condias.de/en/products/diachem/index.html Microcrystalline thin-film BDD electrodes Coated on Nb, Ta, Si, graphite, conductive ceramics Thickness up to 15 pm... 

Nickel metal hydride batteries consist of a positive electrode containing a mixture of carbon/graphite conductive diluent and nickel hydroxide as its principal active material. The negative electrode consists mainly of hydrogen-absorbing... 

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