| Project/Area Number |
03650621
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| Research Category |
Grant-in-Aid for General Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Research Field |
無機工業化学・無機材料工学
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| Research Institution | SHINSHU UNIVERSITY |
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Principal Investigator |
TOUHARA Hidekazu SHINSHU UNIVERSITY, FAC. TEXTILE SCIENCE AND TECHNOLOGY, PROFESSOR, 繊維学部, 教授 (40026141)
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| Co-Investigator(Kenkyū-buntansha) |
OKINO Fujio SHINSHU UNIVERSITY, FAC. TEXTILE SCIENCE AND TECHNOLOGY, LECTURER, 繊維学部, 講師 (60214037)
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| Project Period (FY) |
1991 – 1992
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| Project Status |
Completed (Fiscal Year 1992)
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| Budget Amount *help |
¥1,900,000 (Direct Cost: ¥1,900,000)
Fiscal Year 1992: ¥600,000 (Direct Cost: ¥600,000)
Fiscal Year 1991: ¥1,300,000 (Direct Cost: ¥1,300,000)
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| Keywords | GRAPHITE INTERCALATION COMPOUND / FLUORINE CHEMISTRY / HIGH ELECTRICAL CONDUCTIVITY / CHARGE TRANSFER / TWO DIMENSIONAL PHASE TRANSITION / ANTIMONY TRIFLUORIDE / HYDROGEN FLUORIDE / FLUOROARSENATE |
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| Research Abstract |
1.Fluorine-Graphite Intercalation Compounds C_xF The rate of fluorine intercalation increases with decreasing reaction temperature, and C_xF with the wide composition range (3<x<13) are formed by long reaction times (14-140 days) at a low temperature range (RT - -78ﾟC). The rate of intercalation in the presence of SbF_3 or HF is much faster then that of pure fluorine, and C_xF (3<x<13) are formed by a shorter reaction time than 7 days.
2.Structure of C_xF and Nature of C-F bond The intercalate thickness d_i of C_xF with lower fluorine content than x=6 is 2.7 A^^ﾟ, indicating that intercalated species are fluoride ion and are in the midway between graphite galleries. When the fluorine content exceeds that of C_6F, the nature of C-F bond varies from ionic to semi-ionic and the identity period I_c of stage-2 C_xF becomes 10.6 A^^ﾟ. This suggests that intercalated fluorine atoms are not in the midway between graphite galleries.
3.Charge Transfer and In-Plane Electrical Conductivity sigma_<ab
… More
> Values of sigma_<ab> of C_xF increase with increasing fluorine content and show the maximum (sigma_<ab> = 2.25x10^5 S/cm) at x=8.4. The maximum value is ca. 10 times higher than that of pristine graphite crystal. After the maximum, sigma_<ab> decrease with increasing fluorine content and the fluorine-rich C_xF (x<3) with semi-ionic C-F bond are almost insulators because of pi-electron localization by the semi-ionic C-F bond formation. The some physical properties are deduced by the qualitative analysis of reflectance spectra for stage-2 compound C_<6.1>F. The fermi energy is 0.72 eV, and the charge transfer per carbon atom and the charge transfer per fluorine atom are 0.01 and 0.07, respectively.
4.The Order-Disorder Transition of Stage-1 Graphite Fluoroarsenate. Guinier-Simon X-ray diffraction date for the stage-1 graphite fluoroarsenate intercalation compound, C_<16>AsF_6, indicate that it undergoes an order-disorder transition at ca. 170 K and has the F-ligands of AsF_6^- anions nestled in contiguous three-fold sets of carbon-atom hexagons of the enclosing graphite layers with 3-dimensional ordering of the anions in the low temperature phase. Less
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