Graphite-ferric chloride intercalate

Ritsko (55) have shown that, for the graphite-ferric chloride intercalate, the additional states due to the intercalant species (FeCl ) show up as an increase in the spectral intensity just ahead ofJthe K-ionization edge of carbon. There is also a small chemical shift in the carbon K-level upon intercalation. 

Preparation of finely-divided iron/carbon catalysts for ammonia synthesis by the controlled reduction of graphite/ferric chloride intercalation compounds. K. Kalucki, W. Morawski, and W. Arabczyk (Politechnika Szczecinska). PL 141907 (1988). 

The formation of fullerenes and CNTs has also been affected by their environmental atmosphere [22] and, in particular, a hydrogen atmosphere plays an important role in forming graphitic structures of multi-walled CNTs (MWCNTs) in the form of buckybundles [24]. Intercalation into MWCNTs has been difficult or impossible, because there is no space for intercalants to enter into a Russian-doll-type structure of the nanotubes. However, the buckybundles formed in the hydrogen arc discharge were found to be successfully intercalated with potassium and ferric chloride (FeCl3) without breaking the... 

The first compound of this sort was ferric chloride graphite 21, 84)-Riidorff and Schulz (65) obtained from graphite and ferric chloride at 200-300° a stage 1 compound with 60-70% of ferric chloride. In this compound separate layers of ferric chloride, as they occur in the lattice of the pure FeCls, were intercalated between the carbon planes, which were unchanged, though the distance between them was increased to 9.4 A. 

In attempts to separate ferric chloride and aluminum chloride by intercalation in graphite, Croft (10) found that aluminum chloride could be intercalated either alone or together with ferric chloride. Further work (11, 11a) led to the surprising result that numerous metal chlorides are able to react with graphite. The compounds studied are set out in Table VI, which is taken from Croft s work. It includes thirty... 

Croft explains the results in terms of the acceptor property of the boron atoms. They tend to take an electron pair from a donor molecule to form sp bonds. This is why only halides in lower oxidation states react with boron nitride (e.g., CuCl and SbCls but not Cuds or SbCls) This is different from the case of graphite in which the carbon planes are a source of electrons. The intercalation of aluminum and ferric chlorides is attributed by Croft to bonding by the electron pairs of the nitrogen atoms of boron nitride. It is surprising, however, that boron trifluoride and trichloride, which are particularly good electron acceptors, appear unable to become intercalated. 

There is relevance of these considerations to the processes of activation of carbons (discussed in Chapters 5 and 6). A series of compounds, known as intercalation compounds, exists in which ions and molecules are located between the graphene layers of carbon materials, principally graphitic structures, but not necessarily so. These reactions, leading to the formation of intercalation compounds, involve electron transfer processes. For example, electron transfer from the graphene layer forms a bromine anion (Br ), or electron transfer to the graphene layer forms a potassium cation (K ). Ferric chloride also forms an intercalation compound. 

Kang F, Leng Y, Zhang T (1998), Electrochemical synthesis and characterization of ferric chloride-graphite intercalation compounds in aqueous solution , Garbon, 36(4), 383-390. 

The FeCl -GICs sanples were prepared according to the conaonly used ethod. Powdered natural Sri Lanka graphite with a particle size of 1-20 nicrons in thickness and 30-100 Microns in width was used in this study (Fig.l.). The Mixture of powdered graphite and pure anhydrous ferric chloride (Riedel) was heated at a teMperature of 300 °C for 2A h. The intercalation reaction was carried out with different anounts of FeCl, controlled by means of the ratio of solid grajiiite to solid FeCl in... 

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