松尾 吉晃

Polyaniline (PANT)-intercalated graphite oxides (GOs) were synthesized and theirelectrochemical properties were investigated. Surfactant-intercalated GO dispersed in N-methyl-2-pyrrolidone (NMP) reacted with various amounts of PANI solution in NMP, giving intercalation compounds with I_c values of 1.1nm or 1.3nm. The absorption peak at 2900cm^-1 derived from C-H group in surfactant was not observedin the IR spectra of the obtained intercalation compounds. This indicated that surfactants intercalated into GO layer were completely replaced by PANI via ion exchange reaction. The charge-discharge curve of the intercalation compound with I_c value of 1.1nm was similar to that of GO at the first cycle and to that of PANI at the subsequent cycles. However, it was different from that of the physically mixed GO/PANI composites. The discharge capacity at the 10th cycle for the above intercalation compound was 80 mAh/g.

Fluorine-graphite intercalation compound (C_xF) has been synthesized from HOPG by electrochemical method using solid electrolyte PbSnF₄ in a fluorine atmosphere. The compositions of the obtained C_xF samples were between stage 7+4, C_16.5F and stage 1, C_2.4F. Fluorination was highly promoted by charging and, the fluorine content in the sample increased with increase of the charge. Two types of stage 1 bi-intecalation phases, and the in-plane superlattice with a₀=2a_g and b₀=√3a_g were observed for stage 1, C_2.4F, for which the c-axis and in-plane structure models have been proposed. The calculated intensity of X-ray diffraction lines is in good agreement with observed one.