Interlayer spacing of graphite

X-ray diffraction patterns for different carbon/fluorine ratios demonstrate that the diffractions due to the starting materials disappear and are replaced by new diffractions.12 As shown in Table 2,12 the interlayer spacing of graphite and carbon black increases from 3.37 to 6.06 and 6.7 A. This increase is due to the electrostatic repulsion resulting from the fluorine atoms which have formed a layer above and below the carbon atoms. 

It was established already in the first period of works on sodium ion batteries that contrary to the lithium ion, the sodium ion is not intercalated into the interlayer space of graphite. Sodium ions penetrate nongraphitized carbon materials, but the nature of this penetration is not intercalation. In the case of oil coke, the capacity values of 90 - 95 mAh/g were obtained, which approximately corresponds to the composition of NaC24. In the case of carbon black electrodes, capacity of about 200 mAh/g was obtained. Quite suitable materials for the negative electrode could be different varieties of nanoporous hard carbon (obtained, e.g., by pyrolysis of glucose). In this case, intercalation of sodium ions is provided not only by their intercalation into the interlayer space, but also by their adsorption on the inner nanopore surface. The capacity of electrodes of nanoporous hard carbon reaches 300 mAh/g. Most recently, negative electrodes of carbon nanotubes with nearly similar sodium intercalation capacity were described. 

Shioyama, H. (1997) Polymerization of isoprene and styrene in the interlayer spacing of graphite. Carbon, 35,1664. 

It is reasonable to point out that the interlayer spacing of graphite filled with intercalate is lower for ionic compounds prepared electrochemically in organic... 

Shioyama H (2000), Interactions of two chemical species in the interlayer spacing of graphite , Synth Met, 114, 1. 

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