| Graphite intercalation compounds(GICs) are a series of versatile materials with abundant chemical reactions, electronic and crystal structures. GICs have exhibited promising applications in catalysis, sensing, optics, magnetics and batteries. Developing novel synthesis methods and investigating general formation mechanism are one of the main challenges in this field. In this dissertation, systematic investigation was carried out on new synthesis strategies of GICs, their formation mechanisms and novel properties.The aim of this dissertation is to explore the controlled synthesis processes of GICs. The as-prepared nanomaterials were characterized in detail and their formation mechanism was briefly discussed. The main contents can be summarized as follows:(1) Chemical methods were used to synthesize CrO3-GICs at room temperature under atmospheric conditions. Stage-2 GICs was prepared by mixing predetermined amount of graphite, CrO3 and 12M HCl and keeping the mixture for 15 days. The presence of CrⅥin GICs synthesized was proved by X-ray photoelectron spectroscopy.(2) By the mixing method, stage 7 Bi2O3-GICs, stages 6, 7 ZrO2-GICs, stages 4, 5 MoO3-GICs, stage 5 CrO3-GICs, stage 6 FeCl3-GICs were synthesized. Stage 5 CoCl2-GICs;stages 4, 5, 6 PbCl2-GICs;stages 5, 6 BiCl3-GICs were synthesized by the mixing method for the first time. The domains formed in these GICs were partly folded, forming new stage in the stage transformation. These folding regions remained highly ordered state and gradually increased until the formation of a single stage GICs.(3) A novel one-step synthesis method of pure stage 7 FeCl3-GICs (pure stage 7 KCl, pure stage 6 NiCl2) by an arc discharge in aqueous solution was reported for the first time, which presents a simple and controllable way to synthesize GICs. The structure of the GICs was characterized by X-ray diffraction. The analysis obtained of XRD patterns indicates that a number of non-carbon reactant (atom, molecule, ion or groups) physically intercalated the layers of graphite with reticulated layer structure. Consequently the layered structure of graphite was changed and new physical and chemical properties were thus obtained. The detailed microstructures of as-synthesized products were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy and X-ray photoelectron spectroscopy. The morphology and phase of the products were found to be strongly dependent on reaction conditions. This technique may also have great potentials in preparing other GICs. (4) On the basis of the structural characteristics of rare earth metal oxides, the synthesis and structural characteristics of rare earth metal oxides-graphite intercalation compounds(REO-GICs) were discussed for the first time. In addition, by means of studying the effect of rare earth metal oxides on the structure and properties of GICs, we pointed out the developing trend and the application prospect of REO-GICs. The suitable intercalation conditions were as follows; heating rate 20-30℃/min, treatment time 1h, and temperature 1200℃(2000℃) for stage-5 CeO2 (Eu2O3)-GICs.(5) FeCl3-NiCl2 (CuCl2)-GICs were synthesized by molten salts method. Graphite powder was used as host material and the mixture of NiCl2 (CuCl2) and FeCl3 as intercalant. The influence of reaction conditions on stage structures was discussed such as temperature, time, and graphite-to- chloride molar ratio. The results show that with the change of molar ratio among graphite, NiCl2 (CuCl2) and FeCl3, reaction time and temperature, FeCl3-NiCl2 (CuCl2)-GICs with different stages were obtained. Under the conditions of C/chlorides=4:10(3:10),NiCl2(CuCl2)/FeCl3=3:7(6:4), 450℃(550℃), 25h(30h), the products were stage 1 and stage 2 FeCl3-NiCl2 -GICs and FeCl3-CuCl2-GICs. During the reaction process, NiCl2 partially took the place of preferentially intercalated FeCl3.
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