NMR and bulk measurement of the intrinsic physical properties of highly-purified single-wall carbon nanotubes

2014 Fiscal Year Final Research Report

• Project/Area Number: 25800201
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Condensed matter physics II
• Research Institution: Tokyo Metropolitan University
• Principal Investigator: NAKAI Yusuke 首都大学東京, 理工学研究科, 助教 (90596842)
• Project Period (FY): 2013-04-01 – 2015-03-31
• Keywords: カーボンナノチューブ / 磁性 / 熱電物性 / NMR

Outline of Final Research Achievements

We prepared highly-purified single-wall carbon nanotube (SWCNT) sample by density gradient ultracentrifugation and gel chromatography. We found that semiconducting SWCNT sample exhibits a large Seebeck coefficient that is comparable to the commercial thermoelectric material Bi2Te3. We observed from SQUID measurements that the temperature, diameter, and metallicity dependence of the magnetic susceptibility is consistent with the novel magnetic behavior that was theoretically predicted. We found that the diameter dependence of the NMR relaxation rate in a sample consisting of a mixture of semiconducting and metallic tubes is consistent with theory. A Luttinger parameter estimated in highly-concentrated metallic SWCNT sample was significantly different from that of a sample consisting of a mixture of semiconducting and metallic tubes. We determined a carbon-carbon bond length of an almost single-chirality SWCNT sample by synchrotron x-ray diffraction measurement.

Free Research Field

物性物理