This atypical behavior of na has drawn considerable attention. Five families of intercalates give high electrical. The excess solvent and electrolyte is then removed from. Gic formation but can be effectively modulated by screening na ions. In particular, unlike pure graphite, some graphite intercalation compounds are found to superconduct. 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. Oxidation of c 12 brso 3 f with s 2 o 6 f 2 yields c 16 brso 3 f. Applications of graphite intercalation compounds journal of. Recently, it was discovered that solvatednaion intercalation can occur in graphite even though the insertion of. These compounds are interesting as synthetic metals and as precursors to graphene. We have made a very detailed analysis concentrating on compounds containing bromone, which has extremely large anomalies. Files available from the acs website may be downloaded for personal.
Gics, am li, na, k, rb, cs in various solvent environments, it is demonstrated that the unfavorable local na. Graphite intercalated compounds for easy graphene, generators and synthetic metals duration. Feb 28, 20 graphite intercalated compounds for easy graphene, generators and synthetic metals duration. Nonoxidative intercalation and exfoliation of graphite by. Rapid progress in the reaction led of the formation of graphite fluoride, c2f. Les composes dinsertion du graphite, appeles aussi composes dintercalation du graphite, sont des materiaux complexes qui ont une formule generale xcy ou. Pdf evaluation of layered graphene prepared via hydroxylation. 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. The ultrafast intercalation is demonstrated in real time using millimetersized highly ordered pyrolytic graphite, in which instantaneous insertion of solvatednaions occurs in less than 2 s. Graphite intercalation compounds gics are complex materials having a formula cxm where. One famous intercalation host is graphite, which intercalates potassium as a guest. 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.
Graphite is the most widely used anode material for li. Graphite intercalation compounds containing fluoroanions. A snapshot of a threedimensional dendrite in pure ni with a cubic interfacial energy anisotropy obtained from a phasefield simulation with thermal noises 72 courtesy of a. 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. Pdf layered graphene was prepared via the hydroxylation of potassiumgraphite. Superconductivity in the intercalated graphite compounds.
The presence of intercalation compounds in graphite, i. The immersed graphite particles are subjected to an anodic current and then removed from the electrolyte and rinsed with a solvent. 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. The formation of various stagings with solvatednaions in graphite is observed and precisely quantified for the first time. Fecl 3intercalated graphite intercalation compounds gics show fascinating potential as anodes for highperformance lithium ion batteries libs due to their excellent reaction reversibility, low volume change and high volumetric energy density. Intercalation reactions are known to occur between graphite and literally hundreds of reagents. Paired with li intercalation at the anode, the corresponding dual. If the inline pdf is not rendering correctly, you can download the pdf file here. Graphite intercalation compounds i springer for research. Synthesis and low temperature specific heat of the graphite intercalation compounds khgc4 and khgc s m. Superconductivity in the intercalated graphite compounds c. Using optical and raman microscopy, we perform direct realtime monitoring of stage transitions in h2so4gics made from highly oriented pyrolitic graphite hopg. Graphite intercalation compounds gics are often used to produce exfoliated or functionalised graphene related materials grms in a specific solvent. Despite the recent success in the application of fecl 3gics in libs, the issue of dissolution of chlorides and the relevant liion storage.
Kovtyukhova1, yuanxi wang2, ayse berkdemir2, rodolfo cruzsilva4, mauricio terrones2, vincenth. Graduate thesis or dissertation synthesis, characterization. The graphite intercalated compounds gic deintercalated slowly in air at room temperature, but deintercalated quickly and completely at 370 dc. Facile preparation of graphite intercalation compounds in alkali. One approach is to prepare graphite intercalation compounds gics with low layer charge density and appropriate gallery height, followed by the colloidal dispersion or exfoliation of the resulting gics. Mallouk1,2,3 graphite intercalation compounds are formed by inserting guest molecules or ions between sp2bonded carbon layers. For many decades it has been thought that graphite intercalation must involve hostguest charge transfer, resulting in partial oxidation. Supplementary movie 2 is a more complete description of this experiment. Interestingly, while the metastable high pressure phase c2li exhibits a superconducting transition at 1. Pdf download graphite intercalation compounds i free. Synthesis and low temperature specific heat of the graphite. The intercalation of bromine fluorosulfates into graphite.
The properties of graphite intercalation compounds gics are discussed with respect to possible applications. Preparation of graphite intercalation compounds containing crown. Synthesis of graphite intercalation compounds springerlink. Synthesis of first stage graphite intercalation compounds. Gics with covalent bonds are graphite fluorides and graphite oxide recently called graphene oxide. The field of superconductivity in the class of materials known as graphite intercalation compounds has a history dating back to the 1960s 1 and 2. The first of these to be reported 1,2 was c8k, which has a superconducting transition temperature of 0. Two potassium graphite compounds are kc 8 and kc 24. Graphite intercalation compounds i structure and dynamics. This process is experimental and the keywords may be updated as the learning algorithm improves. When used as a cathode, graphite intercalates a variety of anions with pf6 being among the most common.
Us6756027b2 method of preparing graphite intercalation. Ternary intercalation compound of graphite with aluminum. Usually this energy is supplied by charge transfer between the guest and the host solid, i. Sep 22, 2016 herein, through a systematic investigation of alkali metal graphite intercalation compounds am.
Superconductivity in the intercalated graphite compounds c6yb. Media in category graphite intercalation compounds the following 6 files are in this category, out of 6 total. Click download or read online button to graphite intercalation compounds and applications book pdf for free now. New synthetic strategies have been investigated for nanodimensioned graphite particles or even isolated graphene sheets. The research on graphite intercalation compounds combines both aspects. Graphite intercalation compounds and applications hardcover. The action of bromine1fluorosulfate on graphite has led to the synthesis of several novel intercalation compounds. Pdf layered graphene was prepared via the hydroxylation of potassium graphite. This second volume provides an uptodate status report from expert researchers on the transport, magnetic, elec tronic and optical properties ofthis unique class of materials. Graphite fluoride is a kind of graphite intercalation compounds gics.
Characterization of graphite intercalated by electron acceptors, stanford. Superconductivity in the intercalated graphite compounds c 6. We observe that stage transitions in hopgbased gics occur very. Theory of superconductivity in graphite intercalation compounds. Properties such as composition, temperature of formation, molar ratios, and particle size. Intercalation events visualized in single microcrystals of. Graphite intercalation compounds are a type of graphite compounds. Strong anchoring effect of ferric chloridegraphite. Us3785999a process of making graphitemetal chloride. The progress of materials science depends on the development of novel materials and the development of novel experimental techniques. With decreasing pressure of chlorine the intercalate content of the compounds becomes smaller until, at the. Graphite intercalation compounds continue to be central to technologies for electrochemical energy storage from anodes in established liion batteries to cathodes in beyond liion concepts paired with multivalent anodes.
Graphite intercalation compounds are a new class of electronic materials that are classified as graphitebased host guest systems. View enhanced pdf access article on wiley online library html view download pdf for offline viewing. The first of these 4 shows that superconductivity in the graphite intercalation compounds. The research was motivated by the observation of anomalous mixing frequencies in the dehaasvan alphen spectra of graphite intercalation compounds. They have specific structural features based on the alternating stacking of graphite and guest intercalate sheets. Synthesis and low temperature specific heat of the. The intercalation compounds graphite bisulfate and graphite perchlorate can be prepared by treating graphite with strong oxidizing agents in the presence of strong acids. Intercalation compound graphite crystal alkali metal atom graphite intercalation compound intercalate layer these keywords were added by machine and not by the authors. The first volume addressed the structural and dynamical aspects of graphite intercalation compounds, together with the chemistry and intercalation of new compounds.
The compounds are, for the most part, very unstable in the open laboratory environment, and they must therefore be handled with extreme care and encapsulated in vacuum or in an overpressure of inert gas or reactant. Synthesis and characterization of the graphite intercalation. The insertion of guest species in graphite is the key feature utilized in applications ranging from energy storage and liquid purification to the synthesis of graphene. The second volume will also contain a chapter on applications of graphite intercalation compounds.
Historically, compounds of graphite have been placed in three categories. Synthesis of first stage graphite intercalation compounds with fluorides article pdf available in journal of fluorine chemistry 245. They are interstitial compounds in which the foreign species the intercalate is included in the. Citeseerx document details isaac councill, lee giles, pradeep teregowda. Stage transitions in graphite intercalation compounds. Pdf formation of gic graphite intercalation compound is an important field of study currently, as it offers a method of producing. Graphite intercalation compounds are formed by inserting guest molecules or ions between sp2bonded carbon layers. Graphite intercalation compounds and applications download graphite intercalation compounds and applications ebook pdf or read online books in pdf, epub, and mobi format. Since the compounds are not stable, they could decompose naturally in the presence of.
Chung, in reference module in materials science and materials engineering, 2016. Ferric chloride graphite intercalation compounds prepared from graphite fluoride. Pdf superconductivity in graphite intercalation compounds. A structural characterisation of these compounds shows them to be hexagonal layered systems in the same class as other graphite intercalates. Graphite intercalation compounds are a new class of electronic materials that are classified as graphite based host guest systems. Intercalation compounds of graphite are of interest, both scienfically and technologically because of unusual properties. Intercalation compound an overview sciencedirect topics. Gic and a new ternary system based on dimethylacetamide dmac. The values in table iv, which were obtained with polycrystalline material a t a pressure of 20 kgcm2, are taken from ubbelohdes work. Intercalation compounds of graphite dresselhaus 2002. We observe that stage transitions in hopgbased gics occur very differently from those in. The electromagnetic absorption of a naethylenediamine. The electronic structures show twodimensional metallic properties with a large variety of features.
In this letter we report the discovery of superconductivity in the isostructural graphite intercalation compounds c6yb and c6ca, with transition temperatures of 6. Intercalation compounds of graphite are of interest, both scienfically and technologically because of unusual properties that derive mainly from high degree of crystal anisotropy. Experimental details, ex situ pxrd patterns, and gcms studies pdf. Ferric chloride graphite intercalation compounds prepared. Despite intensive and longlasting research on graphite intercalation compounds gic, the mechanism of the stage transitions remains unclear. Nomenclature and terminology of graphite intercalation compounds pdf. Conditions for reversible na intercalation in graphite. The nearest layer model for the intralayer vibrational excitations of graphite intercalation compounds is described in detail and justified by data on both donor and acceptor compounds. Gic made from graphite flakes was used to study the microwave absorption performance of a gic for the first time. Preparation of graphite intercalation compounds containing crown ethers. The stages of graphite intercalation compounds are labeled as stage 1, stage 2, etc. Pdf synthesis of intercalation compound of graphite and its.