These are unprecedented in the field of graphite intercalates. Doc intercalation compounds of graphite israel palchan. These materials are deeply colored solids that exhibit a range of electrical and redox properties of potential applications. Different stacking of graphene layers with the a4 ab sequence in graphite and. Graphite can incorporate a wide range of intercalate guests between planar graphene sheets to form graphite intercala tion compounds gics. The electronic structures show twodimensional metallic properties with a large variety of features.
Usually this energy is supplied by charge transfer between the guest and the host solid, i. Raman spectra for both amorphous bc2n and bc4n compounds. Irreversibility at macromolecular scales in the flake graphite of the. The typical 1st stage compound has a composition of c6falf3o,i5 with a repeat distance of 940 pm. Graphite intercalation compounds are a new class of electronic materials that are classified as graphite based host guest systems. Solin department of physics, michigan state university, east lansing, michigan 48824, u. Graphite intercalation compounds containing fluoroanions. Synthesis of first stage graphite intercalation compounds. F are prepared for the first time by the intercalation of fluorotrispentafluoroethylborate anion. The electronic structures show twodimensional metallic properties with a large variety of features including superconductivity. Nicholls department ofphysics and center for materials science and engineering, massachusetts institute oftechnology, cambridge, massachusetts 029 j. Rapid progress in the reaction led of the formation of graphite fluoride, c2f. Preparation of graphite intercalation compounds containing.
Applications of graphite intercalation compounds journal. Synthesis of first stage graphite intercalation compounds with fluorides article pdf available in journal of fluorine chemistry 245. The first of these to be reported 1,2 was c8k, which has a superconducting transition temperature of 0. The influence of three different intercalation methods on. Intercalation chemistry of graphitelike layered material bc6n for. The excess solvent and electrolyte is then removed from the graphite particles. Factors affecting the exfoliation of graphite intercalation. It has only about 10 4 charge carriers per carbon atom. Preparation of graphite intercalation compounds containing oligo and polyethers h. Alkali metal graphene plane graphite intercalation compound graphite lattice pristine graphite these keywords were added by machine and not by the authors. These gics are obtained by electrochemical oxidation of graphite in a nitromethane electrolyte.
While the stage transition, changing the number of graphene layers sandwiched between the two layers of intercalant, is fundamentally important and has been theoretically addressed, experimental studies revealed only macroscopic parameters. Pdf although graphite and hexagonal form of bn hbn are isoelectronic and have very similar. Intercalating graphite sulfuric acid intercalated graphite. In general, the graphite sheets in simple stage1 gics form in an aaa stacking arrangement.
The research on graphite intercalation compounds combines both aspects. Graphite is one material whose properties are quite remarkable. The stages of graphite intercalation compounds are labeled as stage 1, stage 2, etc. Ferric chloride graphite intercalation compounds prepared. This leaves, what are sometimes referred to as galleries, in the centre of, and in between, the hexagons of adjacent graphite layers. Kovtyukhova1, yuanxi wang2, ayse berkdemir2, rodolfo cruzsilva4, mauricio terrones2, vincenth. Intercalation compounds of graphite are of interest, both scienfically and technologically because of unusual properties that derive mainly from high degree of crystal anisotropy. Intercalation compounds article about intercalation. Nonoxidative intercalation and exfoliation of graphite by. Therefore, many substances, what is called intercalates, can enter into the gallery of the graphite to form graphite intercalation compounds gics. Natural flake and synthetic graphite nearly split the market, with.
The immersed graphite particles are subjected to an anodic current and then removed from the electrolyte and rinsed with a solvent. The functional groups usually found in graphite oxide are carbonyl co, hydroxyl oh. Graphite intercalation compounds are synthetic metals formed by inserting layers of atoms or molecules of a guest chemical species between the layers of carbon atoms that make up graphite. The research on graphite intercalation compounds often acts as a forerunner for research in other sciences. Layered graphene was prepared via the hydroxylation of potassium graphite intercalation compound kc 8 produced from exfoliated graphite flake powder. Some spacing distances a, of carboncarbon bonds dc c are given in table 8. Alkali metal gics, like kc 24, are classi ed as donor compounds because the metal atoms donate charge. Speck department ofmaterials science and engineering, massachusetts institute of.
Superconductivity in graphite intercalation compounds. A method of preparing graphite intercalation compounds in which graphite particles are immersed in an aqueous electrolyte media comprising both an acid and an oxidizing agent. Gaier nasa lewis research center, cleveland, ohio 445 max l. Graphite intercalation compounds and applications toshiaki. The invention also provides a process for producing the.
A ternary intercalation compound of graphite with aif3 and f2, cxfa1f3j was prepared under fluorine atmosphere a t temperatures of 20400 c. The resulting products are called graphite intercalation compounds gic or expandable. Pdf download graphite intercalation compounds i free. Compared to the alternatives, graphite has a moderate specific. Graphite intercalation compounds gic possess a broad range of unique properties that are not specific to the parent materials. About a handred kinds of intercalants are listed in the case of singlespecies intercalation. This element is unique in that its unique electronic structure allows for hybridization to build up sp3,sp2, and sp networks and, hence, to form more known stable allotropes than any. The study of physical properties of the graphite compounds, together with elucidation of structures by xrays, has led to a deep insight into the mode of reaction of graphite and the constitution of intercalation compounds. Applications of graphite intercalation compounds journal of.
Superconductivity in the intercalated graphite compounds c6yb. Synthesis of intercalation compound of graphite and its characterisation conference paper pdf available november 2012 with 1,002 reads how we measure reads. Mallouk1,2,3 graphite intercalation compounds are formed by inserting guest molecules or ions between sp2bonded carbon layers. Graphite intercalation compounds gics are complex materials having a formula cxm where. Pdf intercalation of graphite and hexagonal boron nitride by lithium. Aug 07, 2017 because graphite is a bulk material and actually composed of millions of single atom thick sheets of carbon, it opens up new and interesting ways of modifying its material properties. The graphite intercalation compounds and their applications. These compounds are interesting as synthetic metals and as. The intercalation compounds graphite bisulfate and graphite perchlorate can be prepared by treating graphite with strong oxidizing agents in the presence of strong acids. Alkali metal gics, like kc 24, are classi ed as donor compounds because the metal atoms donate charge to the graphite conduction band. In a firststage or stage 1 compound, single layers of graphene alternate.
Graduate thesis or dissertation graphite intercalation. Since the compounds are not stable, they could decompose naturally in the presence of. Graphite intercalation compounds as precursors of graphene. Polyethers preparation of graphite intercalation compounds. Ternary intercalation compound of graphite with aluminum. Nicholls department ofphysics and center for materials science and engineering, massachusetts institute oftechnology.
From a comparative study on various intercalation systems, we find that, depending on the intercalant species, the exfoliation energies vary significantly, not only due to the size of intercalants but also due to interactions with the. Nonoxidative intercalation and exfoliation of graphite by bronsted acids nina i. The compound comprises carbon, oxygen and hydrogen, obtained by treating graphite with strong oxidisers. They have specific structural features based on the alternating stacking of graphite and guest intercalate sheets. Evaluation of layered graphene prepared via hydroxylation of. An additional experiment tested three different kinds of graphite fluorides under reaction with feci 3 they included two graphite fluorides made from pitchbased carbon fibers, p55 and p25, and a commercially available graphite fluoride powder. Direct realtime monitoring of stage transitions in graphite. Vibrational excitations in pristine graphite and in graphite intercalation compounds are discussed.
In particular, unlike pure graphite, some graphite intercalation compounds are found to superconduct. In both cases, the obtained graphite intercalation compounds gics, present a lamellar structure in which the planar shape of the graphene layers remains unchanged. Properties of novel cvd graphite fibers and their bromine intercalation compounds james r. Two potassium graphite compounds are kc 8 and kc 24. Nomenclature and terminology of graphite intercalation compounds pdf. Graphite intercalation compounds gics, formed by inserting ionic species into the lattice of the graphite structure, are typically layered materials consisting of intercalate guest and graphite layers 7, 8. The first graphite intercalation compounds containing tris. Pdf synthesis of intercalation compound of graphite and. Many of these materials are highly anisotropic, so that interatomic interactions can for all practical purposes be neglected along one or two crystal axes. Us6756027b2 method of preparing graphite intercalation. A stage n intercalation compound has n graphene layers. Graphite intercalation compounds are a new class of electronic materials that are classified as graphitebased host guest systems. Preparation and structural investigation of cucl2 graphite.
The compounds are still first stage binary graphite intercalation compounds. New chemical synthesis strategies have been investigated for the preparation of acceptortype graphite intercalation compounds gics with fluoroanions in order to obtain new materials and to develop a better understanding of the synthetic approaches and properties of the products. Properties such as composition, temperature of formation, molar ratios, and particle size. Dicenzo bell laboratories, 600 mountain avenue, murray hill, new jersey 07974, usa abstract carbon is xray photoemission spectra of alkali graphite intercalation compounds are shown to provide detailed. The progress of materials science depends on the development of novel materials and the development of novel experimental techniques. Binary graphite intercalation compounds sciencedirect. In contrast to the potassium and calcium graphites, the carbon layers are oxidized in this process. Because graphite is a bulk material and actually composed of millions of single atom thick sheets of carbon, it opens up new and interesting ways of modifying its material properties. The formation of graphite compounds is linked in every case to a change in the electron concentration in the graphite. The invention provides a graphite fluorine intercalation product of the formula c. The properties of graphite intercalation compounds gics are discussed with respect to possible applications. Because carbon occupies a middle position in the order of electronegativity of the elements in the periodic table, graphite welcomes many chemicals as guests, or intercalants, making it possible to produce. One of the oldest classes of prototype systems for exploring phenomena predicted to. Citeseerx document details isaac councill, lee giles, pradeep teregowda.
One famous intercalation host is graphite, which intercalates potassium as a guest. Pdf synthesis of intercalation compound of graphite and its. In summary, we have synthesised two new isostructural graphite based superconductors, c6yb and c6ca, with superconducting transition temperatures of 6. For instance, the concept of staging, which is fundamental to graphite intercalation compounds, is also relevant to surface science in connection with adsorbates on metal surfaces and to hightemperature superconducting oxide layer materials. Graphite intercalation compounds gics are a unique class of lamellar. Layered graphene was prepared via the hydroxylation of potassiumgraphite intercalation compound kc 8 produced from exfoliated graphite flake powder. Jan 31, 2011 the properties of graphite intercalation compounds gics are discussed with respect to possible applications. Graduate thesis or dissertation graphite intercalation with. This process is experimental and the keywords may be updated as the learning algorithm improves.
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