Among the modified graphite materials, graphite intercalation compounds gics have certainly attracted the attention of theoretical physicists, chemists, and industrialists. 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. A recent survey indicates that h 2 so 4based gics were reported in literature as early as 1841. In particular, unlike pure graphite, some graphite intercalation compounds are found to superconduct. The dopant impurity ion will incoporate into the material. Applications of graphite intercalation compounds journal of. Download limit exceeded you have exceeded your daily download allowance. Nomenclature and terminology o graphite intercalation compounds 1895. From graphite intercalation compounds to nanographene. Before reaction, the interplanar spacing for pristine p1 00, p55, and p25 was 3.
Graphite intercalation compounds gics are formed by insertion of certain. 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 graphite intercalation compounds and their applications. Layered graphene was prepared via the hydroxylation of potassiumgraphite intercalation compound kc 8 produced from exfoliated graphite flake powder. Electrochemistry of graphite intercalation compounds.
The influence of three different intercalation methods on the. Layered graphene was prepared via the hydroxylation of potassium graphite intercalation compound kc 8 produced from exfoliated graphite flake powder. Classification and discussion of the processes from new experimental data relative to graphiteacid compounds p. Therefore, many substances, what is called intercalates, can enter into the gallery of the graphite to form graphite intercalation compounds gics. Graphite intercalation compounds gics have atomic or molecular layers. Intercalation compounds of graphite are of interest, both scienfically and technologically because of unusual properties that derive mainly from high degree of crystal anisotropy. Under certain conditions, the graphite intercalation compounds were formed containing intercalated anions of peroxosulphuric acids peroxomonosulphuric or peroxodisulfuric. The ocv method has been used to study some intercalation compounds, such as lixtis2 or manganese oxides. Lithiumion intercalation and deintercalation behaviors of. The properties of graphite intercalation compounds gics are discussed with respect to possible applications. The progress of materials science depends on the development of novel materials and the development of novel experimental techniques. Here we report direct time and spaceresolved, alloptical measurement of li intercalation. Five families of intercalates give high electrical conductivity to gics.
Graphite intercalation compounds 235 the network of carbon hexagons remains, with a cc distance, as in graphite. The intercalation of both pf6 and tfsi could be confirmed by cyclic voltammetry in electrodes made of carbon blacks. Storylines in intercalation chemistry rsc publishing. Jan 31, 2011 the properties of graphite intercalation compounds gics are discussed with respect to possible applications. The miller hydrothermal lumpvein historical graphite mine is located 80 km west of montreal in the grenville township and exhibits extremely high purity graphite grading 100% cg. Thin films of macromolecular wires cast from solution. This results in a more or less pronounced expansion which may be detected by xray diffraction and which occurs in a direction perpendicular to the carbon sheets. Vibrational excitations in pristine graphite and in graphite intercalation compounds are discussed. Factors affecting the exfoliation of graphite intercalation. When a small amount of water was dropped onto the kc 8 in an oxygenfree atmosphere, the stage structure of the intercalation compounds was broken, and agglomerated graphene was obtained. Lithium intercalation into graphite is a critical process in energy storage technology. The graphite network is also preserved in graphite fluorinated by f carriers at. The electronic structures show twodimensional metallic properties with a large variety of features including superconductivity.
About a handred kinds of intercalants are listed in the case of singlespecies intercalation. Abstract graphite carbon has been successfully used for the anode materials of secondary. The second volume will also contain a chapter on applications of graphite intercalation compounds. In contrast to the potassium and calcium graphites, the carbon layers are oxidized in this process. Intercalation is the process by which a molecule acting as an intercalant can migrate and deposit between two others, in this case being the graphene layers of the graphite crystal. The research on graphite intercalation compounds combines both aspects.
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. Nonoxidative intercalation and exfoliation of graphite by bronsted acids nina i. In contrast, a metal atom can donate an electron to the network and form a donortype gic, i. The first of these to be reported 1,2 was c8k, which has a superconducting transition temperature of 0.
Many years of collaboration by toshiaki enoki toshiaki enoki mgm 1984 reflects on the year he spent as a visiting scientist in millies group, and on the many years of collaboration since. Each of the bc, cn and bcn materials has a unique intercalation chemistry, which will be compared with that of graphite. Various heat treatments were then used to test the stability of these compounds, resulting in reaction prooucts b3 and a 2 to e2. Electrical, thermal and magnetic properties can be varied by intercalation, making these. 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.
When exposed to high potentials, carbon blacks experienced strong activation in the 1st cycle, which promotes the perception for anion intercalation, and thus increases the anion intercalation capacity in the following cycles. Properties such as composition, temperature of formation, molar ratios, and particle size. As negative electrode materials for lithiumion batteries, graphitized carbon nanospheres gcnss exhibit excellent capacity retention and highrate capability. We use a single crystal graphite electrode with lithographically defined disc geometry. Studies of li intercalation kinetics have proved challenging due to structural and phase complexity, and sample heterogeneity. What is the difference between intercalation and doping. Recently, interest in aluminium ion batteries with aluminium anodes, graphite cathodes and ionic liquid electrolytes has increased. A structural characterisation of these compounds shows them to be hexagonal layered systems in the same class as other graphite intercalates.
Because of the layered nature of natural flake graphite, it can be modified by processes of intercalation and exfoliation. Graphite intercalation compounds gics are an interesting and highly studied field. They have specific structural features based on the alternating stacking of graphite and guest intercalate sheets. This process is experimental and the keywords may be updated as the learning algorithm improves. Solin department of physics, michigan state university, east lansing, michigan 48824, u. Nonoxidative intercalation and exfoliation of graphite by. The influence of three different intercalation methods on. Mar 20, 2018 from graphite intercalation compounds to nanographene. Alkali metal graphene plane graphite intercalation compound graphite lattice pristine graphite these keywords were added by machine and not by the authors. The resulting products are called graphite intercalation compounds gic or expandable.
Graphite intercalation compounds and applications toshiaki. These materials are deeply colored solids that exhibit a range of electrical and redox properties of potential applications. Synthesis of first stage graphite intercalation compounds. We have shown that the graphite could be suitable for use in nuclear reactors, with a calculated ebc of 0. The doping effect is confirmed by hall and raman measurements and the intercalation process is. Intercalation of fewlayer graphite flakes with fecl3 university of. The stages of graphite intercalation compounds are labeled as stage 1, stage 2, etc. 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.
The rate of fluorine intercalation in graphite is larger in the present system than in. Media in category graphite intercalation compounds the following 6 files are in this category, out of 6 total. Synthesis of graphite intercalation compounds by a soft. Kovtyukhova1, yuanxi wang2, ayse berkdemir2, rodolfo cruzsilva4, mauricio terrones2, vincenth. Superconductivity in the intercalated graphite compounds c6yb. Superconductivity in graphite intercalation compounds. Superconductivity in the intercalated graphite compounds. Intercalation compound for the development of a grey water recycling system by adsorption and electrochemical regeneration rukayat oki school of computing, science and engineering college of science and technology university of salford, salford, uk submitted in partial fulfilment of the requirements of the. The 2s and 2p, 2p, orbitals combine to make inplane 0 bonding orbitals. Advanced rechargeable aluminium ion battery with a high. Crystalline perfection and amount of prismatic edges were found to be important graphite properties determining the intercalation rate.
Preparation and structural investigation of cucl2 graphite. When an electronegative species accepts an electron and forms an ionic bond with this. Graphite intercalation compounds i structure and dynamics. Table 1 indicates the continuous efforts, successes and developments in this area during the past 15 decades. The study of band structure of graphite intercalation compound containing sodium calculated using density functional theory. Stage transitions in graphite intercalation compounds. Essential properties of lili graphite intercalation compounds arxiv. In the examples of the materials given above, an important component under. Electrical, thermal and magnetic properties can be. The role of carbonate solvents on lithium intercalation. The intercalation rate depended on temperature, on graphite properties, and on partial pressures of aluminum chloride and chlorine. Znmg and nbcl 5 were intercalated in graphite and the presence of such molecules between the graphene sheets results in n and ptype doping, respectively.
Intercalation is when a molecule or ion inserts reversibly between the layers of a compound like potassium ions between graphite layers. The electronic structures show twodimensional metallic properties with a large variety of features. Novel aspects of graphite intercalation by fluorine and. Evaluation of layered graphene prepared via hydroxylation. Graphite intercalation compounds are a new class of electronic materials that are classified as graphitebased host guest systems. Chargeinduced dimensional changes as a function of charge injection are predicted for graphite intercalation compounds by the means of geometry optimization with density functional theory. 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.
Classification and discussion of the processes from new experimental data relative to graphite acid compounds p. Raman spectroscopy of graphite intercalation compounds. Evaluation of layered graphene prepared via hydroxylation of. Ferric chloride graphite intercalation compounds prepared. Since, however, only every fourth carbon atom gives an electron for bonding fluorine, it is understandable that the compound still conducts electricity. Mallouk1,2,3 graphite intercalation compounds are formed by inserting guest molecules or ions between sp2bonded carbon layers. Since the compounds are not stable, they could decompose naturally in the presence of.