Graphite nitrate

STABILIZATION OF GRAPHITE NITRATE VIA CO-INTERCALATION OF ORGANIC COMPOUNDS... 

Graphite nitrate stabilization co-intercalation exfoliation proton... 

The aim of the present work is to elucidate the mechanism for the stabilization of graphite nitrate via cointercalation of different kinds of organic compounds. 

Table. Expansion coefficients and stability indices of modified graphite nitrates. 

Figure 1. PXRD patterns (001) of the products of successive modifications A - initial graphite nitrate B - graphite nitrate modified with glacial acetic acid C - graphite nitrate successively modified with glacial acetic acid and water.

The PXRD pattern does not change after the treatment of graphite nitrate with acetic acid (Fig. 1 B), indicating the conservation of Ic and the stage number of the GIC when nitric acid is partially substituted by acetic acid. Note that both initial graphite nitrate and that modified with acetic acid are thermally unstable (see the Table above.)... 

On modifying graphite nitrate, as follows from the material balance of the reaction, a major part of nitric acid is replaced by the organic intercalant. The latter, if it is protonated by the rest of nitric acid in the interlayer space, is capable of the strong hydrogen bonding with two... 

Despite a wide range of the modifiers used, there is a clear symbasis between the calculated proton affinities and the experimental stability indices Kst (Figure 3). The decrease in concentration of nitric acid in the interlayer space will give rise to a poorer stability of GICs, if the proposed stabilization mechanism is valid. To verify this assumption, the treatment of graphite nitrate with 25-fold excess of acetic acid, compared to that used in the above procedure, was carried out in a glass column. Most of the molecules of nitric acid are probably removed from the interlayer space under such a treatment. It turns out that this procedure reduces the expansion... 

Forsman W.C., Mertwoy H.E., Wessbecher D.E. Nonreductive spontaneous deintercalation of graphite nitrate. Carbon 1988 26 693-699. 

Savoskin M.V., Yaroshenko A.P., Mysyk R.D., Shologon V.I., Khripunov S.V. Synthesis of expandable residual graphite nitrate stabilized with glacial acetic acid. Proceedings of the International Conference on Carbon 2003 Oviedo, Spain. P. 188-189. 

Inagaki M. Graphite-nitrate residue compounds with a smaller interlayer spacing than graphite. Carbon 1967 5 317-8. 

Figure 4. TEM images of nanoscrolls preparedfrom graphite nitrate.

The process of producing the new kind of carbon nanomaterials namely carbon nanoscrolls from graphite nitrate is proposed which differs in advance from other techniques in its simplicity, availability of raw material, low level of energy consumption. 

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