Edge plane

B, abbret. (Eratarrungapunkt) freezing point. Ecket f. corner, angle edge (plane angle)... 

The mechanism of oxidation of the basal plane and that of the cross-section are entirely different (Fig. 10). Oxygen content on the cross-section rises with oxidation, while that on the basal plane drops from about 10 to 1 percent. This may correlate with the decrease in the ratio of edge planes to basal planes due to selective burning of the edge planes. 

The anodic behavior of carbon materials, such as acetylene black, activated carbon, and vapor-grown carbon fiber, in LiC104/PC solution was studied by Yamamoto et al. [102]. Irreversible reactions, including gas evolution and disintegration, were mainly observed on that part of the surface occupied by the edge planes of the... 

Shi C, Anson EC. 1990. Catalytic pathways for the electroreduction of oxygen by iron tetra-kis(4-iV-methylpyridyl)porphyrin or iron tetraphenylporphyrin adsorbed on edge plane pyrol3dic graphite electrodes. Inorg Chem 29 4298. 

Fig. 5.27 Oxygen functional groups on the edge plane of graphite...

Several strategies based on porphyrin derivatives have been developed to reach this objective. The first approach involves the utilization of dimeric cofacial metallic porphyrins adsorbed on the surface of an edge-plane graphite (EPG) electrode.18 An 02 molecule was expected to be coordinated to form a fi-02 bridge between the two metal centers allowing subsequent scission of the O O bond by reductive activation, while the dimeric structure acts as a four-electron reservoir. 

The reaction at the anode in Li-Ion cells is given in Equation 1. During charge the lithium ions approach the surface of the carbon where they accept an electron and enter the lattice. On discharge, the opposite reaction occurs. The electrochemical reaction is thought to occur on the edge planes and not the basal plane of the carbon/graphite particles. 

Synthetic graphite flakes, obtained from Timrex Inc., whose morphology has been characterized by a high level of crevices in the facets perpendicular to the basal planes, through which lithium ions are inserted into the graphite lattice (edge planes). 

Natural graphite (NG) particles, which have smoother facets and a lesser amount of crevices in their edge planes. 

The main issue of this paper relates to the morphological aspects of the graphite particles. As described above, the three types of graphite particles, which are the subject of this study, differ in their pristine morphology, mainly in the roughness and the level of crevices in their edge planes (perpendicular to the basal planes).25... 

From the above discussion, it is clear that the stabilization or failure of graphite electrodes depends on a delicate balance between passivation phenomena (due to the formation of highly cohesive and adhesive surface films) and a buildup of internal pressure due to the reduction of solution species inside crevices in the graphite particles. This delicate balance can be attenuated by both solution composition (EC-DMC vs. EC-PC or PC, etc.) and the morphology of the graphite particles (i.e. the structure of the edge planes and the presence of crevices). 

In this paper, we presented new information, which should help in optimising disordered carbon materials for anodes of lithium-ion batteries. We clearly proved that the irreversible capacity is essentially due to the presence of active sites at the surface of carbon, which cause the electrolyte decomposition. A perfect linear relationship was shown between the irreversible capacity and the active surface area, i.e. the area corresponding to the sites located at the edge planes. It definitely proves that the BET specific surface area, which represents the surface area of the basal planes, is not a relevant parameter to explain the irreversible capacity, even if some papers showed some correlation with this parameter for rather low BET surface area carbons. The electrolyte may be decomposed by surface functional groups or by dangling bonds. Coating by a thin layer of pyrolytic carbon allows these sites to be efficiently blocked, without reducing the value of reversible capacity. 

The fact that aconitase is positively charged (p/ = 8.5), not only agrees with the successful response at the negatively charged edge-plane... 

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