Graphite intercalation compounds pdf merge

Graphite intercalation compounds gic are the most common precursors for expanded graphites which are promising materials for many applications. C8k the electronic band structure of the firststage. It is due to the tendency of the intercalate in the graphite to vaporize, thus forming gas pockets which may or may not burst. Intercalation compounds an overview sciencedirect topics. Abstract graphite carbon has been successfully used for the anode materials of. Xing hai wei, lang liu, jin xi zhang, jing li shi, quan gui guo hclo4 graphite intercalation compound and its thermally exfoliated graphite materials letters 63 16181620 2009. The progress of materials science depends on the development of novel materials and the development of novel experimental techniques. About a handred kinds of intercalants are listed in the case of singlespecies intercalation. The ocv method has been used to study some intercalation compounds, such as lixtis2 or manganese oxides. Properties such as composition, temperature of formation, molar ratios, and particle size. F 0 x lower graphitization form graphite intercalation compounds gics which are w br2 formed the most stable gics the transition metal chlorides appear however, it introduci ion carbon and graphite fibers are being utilized in increasing quantities in the aerospace industry because of their high strength up to 3. Graphite intercalation compounds gic possess a broad range of unique properties that are not specific to the parent materials. Preparation and structural investigation of cucl2 graphite. Physica 6b 1986 16 northholland, amsterdam chapter 1 adsorbed systems structure.

Five families of intercalates give high electrical conductivity to gics. Intercalation compounds article about intercalation. Rapid progress in the reaction led of the formation of graphite fluoride, c2f. Stability of bromine, iodine monochloride, copper 11. Effects of the input of oxidant and intercalating agent on the ev of gics were discussed. Here we report direct time and spaceresolved, alloptical measurement of li intercalation. The graphite intercalation compounds and their applications. Alkali metal graphene plane graphite intercalation compound graphite lattice pristine graphite these keywords were added by machine and not by the authors. The excess solvent and electrolyte is then removed from the graphite particles. Graphite intercalation compounds containing fluoroanions. The exfoliation involves a large expansion by as many as several hundred times along the caxis. The first of these to be reported 1,2 was c8k, which has a superconducting transition temperature of 0. A series of gics with different expanding volumes ev were prepared by a twostep chemical intercalation way. Overview on the intercalation of gold into graphite halcea.

Superconductivity in the intercalated graphite compounds. These compounds are interesting as synthetic metals and as. Graphite intercalation compounds are a new class of electronic materials that are classified as graphitebased host guest systems. Citeseerx document details isaac councill, lee giles, pradeep teregowda. Media in category graphite intercalation compounds the following 6 files are in this category, out of 6 total. Nonoxidative intercalation and exfoliation of graphite by. The influence of three different intercalation methods on the properties of exfoliated graphite xandra van heerden submitted in partial fulfilment of the requirements for the degree masters degree chemical engineering in the faculty of engineering, built environment and information technology. Essential properties of lili graphite intercalation compounds arxiv.

Graphite intercalation compounds 247 tion to the question of the bonding in these compounds by measuring the electrical conductivity of potassium graphite of various compositions 48. Kovtyukhova1, yuanxi wang2, ayse berkdemir2, rodolfo cruzsilva4, mauricio terrones2, vincenth. Preparation of graphite intercalation compounds containing crown. Structure and dynamics of graphite intercalation compounds. Superconductivity in graphite intercalation compounds. Stage transitions in graphite intercalation compounds. Effective and debye temperatures of alkalimetal atoms in normal and ternary graphite intercalation compounds p. Applications of graphite intercalation compounds journal. 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. Many of these materials are highly anisotropic, so that interatomic interactions can for all practical purposes be neglected along one or two crystal axes. The influence of three different intercalation methods on. 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. Us6756027b2 method of preparing graphite intercalation. The graphite intercalated compounds gic deintercalated slowly in air at room temperature, but deintercalated quickly and completely at 370 dc.

Intercalation and stitching of graphite oxide with. Zabel department of physics and materials, research laboratory, university of illinois at urbanachampaign, 1110 w. This process is experimental and the keywords may be updated as the learning algorithm improves. The intercalation reaction of graphite oxide with diaminoalkanes, with the general formula h2nch2nnh2 n 410, was studied as a method for synthesizing pillared graphite with tailored interlayer spacing. Direct realtime monitoring of stage transitions in.

Studies of li intercalation kinetics have proved challenging due to structural and phase complexity, and sample heterogeneity. In contrast to the potassium and calcium graphites, the carbon layers are oxidized in this process. The typical 1st stage compound has a composition of c6falf3o,i5 with a repeat distance of 940 pm. Facile preparation of graphite intercalation compounds in alkali. The properties of graphite intercalation compounds gics are discussed with respect to possible applications. Since the compounds are not stable, they could decompose naturally in the presence of. 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. Electrical, thermal and magnetic properties can be. Graphite intercalation compounds tend to exfoliate upon heating. Synthesis of first stage graphite intercalation compounds.

Two potassium graphite compounds are kc 8 and kc 24. 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. The immersed graphite particles are subjected to an anodic current and then removed from the electrolyte and rinsed with a solvent. They have specific structural features based on the alternating stacking of graphite and guest intercalate sheets. In particular, unlike pure graphite, some graphite intercalation compounds are found to superconduct. Xrd characterization, combining with density functional theory dft. One famous intercalation host is graphite, which intercalates potassium as a guest. Synthesis of first stage graphite intercalation compounds with fluorides article pdf available in journal of fluorine chemistry 245. The electronic structures show twodimensional metallic properties with a large variety of features including superconductivity. Graphite intercalation compounds as precursors of graphene. Graphite intercalation compounds gics are formed by insertion of certain atomic.

The electronic structures show twodimensional metallic properties with a large variety of features. The synthesis of potassiumgold graphite intercalation compounds. The research on graphite intercalation compounds combines both aspects. Intercalation compounds of graphite dresselhaus 2002. We use a single crystal graphite electrode with lithographically defined disc geometry. Pdf thermal expansion and lattice anharmonicity of. In a firststage or stage 1 compound, single layers of graphene alternate. Ternary intercalation compound of graphite with aluminum.

Lithium intercalation into graphite is a critical process in energy storage technology. Recently, it was discovered that solvatednaion intercalation can occur in graphite even though the insertion of na ions alone is thermodyn. The stages of graphite intercalation compounds are labeled as stage 1, stage 2, etc. For synthesis of the biintercalation compounds, crclcdc12and crclmnclgbics, the synthesized stage3 crclgic in which two graphite interlayers out of three remain unoccupied was used as a starting material. Mallouk1,2,3 graphite intercalation compounds are formed by inserting guest molecules or ions between sp2bonded carbon layers. Synthesis of intercalation compound of graphite and its characterisation conference paper pdf available november 2012 with 1,002 reads how we measure reads. Ferric chloride graphite intercalation compounds prepared. Usually this energy is supplied by charge transfer between the guest and the host solid, i. Ferric chloride graphite intercalation compounds prepared from graphite fluoride. Under certain conditions, the graphite intercalation compounds were formed containing intercalated anions of peroxosulphuric acids peroxomonosulphuric or peroxodisulfuric. The alng cell was constructed in a pouch cell methods using a thin al foil thickness. The intercalation compounds graphite bisulfate and graphite perchlorate can be prepared by treating graphite with strong oxidizing agents in the presence of strong acids. The values in table iv, which were obtained with polycrystalline material a t a pressure of 20 kgcm2, are taken from ubbelohdes work.