Production of C60 plasma

Abstract

Production and separation of C60 and C70 as an undergraduate experiment Am.An ultrafine-particle plasma consisting of electrons, positive Kf ions, and large negative C;e ions is produced by introducing "Buckminsterfullerene, C 60" particles into a low-temperature (~0.2 eV) potassium plasma column confined by a strong axial magnetic field. With an increase in the C, fraction, the electron shielding decreases, yielding clear effects on plasma collective phenomena, which are demonstrated for low-frequency electrostatic plasma-wave propagations and instabilities. This plasma might be useful for producing new &-based materials.

Structural deformation of single-walled carbon nanotubes and fullerene encapsulation due to magnetized-plasma ion irradiation

“…10 As a development of this work our concern is here focused on the formation of functional SWNTs such as N-P doped nanotubes, which are expected to show nonlinear electronic properties according to the recent theoretical simulation. 11 In this letter, we report results of bias-voltage application to SWNTs immersed in magnetized plasmas, which contain oppositely charged ions of different species, demonstrating an effectiveness of our method of the plasmaion irradiation to SWNTs for the purpose mentioned above.…”

“…Finally, an alkali-fullerene plasma ͑Li ϩ -C 60 Ϫ , Na ϩ -C 60 Ϫ , or K ϩ -C 60 Ϫ ͒ is generated downstream from the hot cylinder region. 10 Figure 1͑b͒ shows typical current (I sub ) -voltage characteristics of the substrate, to which dc bias voltages ap are applied with respect to the grounded hot plate. In the case of the alkali-fullerene plasma the negative-saturation current of the characteristic apparently decreases around the plasma core region (͉r͉ϭ0 cm), but the positive-saturation current highly increases in the periphery region (͉r͉ϭ1.5 cm) in comparison with the case of the alkali-metal plasma.…”

Nanocarbon materials fabricated using plasmas

“…The Li ? ions neutralized by the electrons were effectively transported along magnetic field lines (B = 500 G) toward the substrate at the other end of the chamber, while a C 60 oven was situated around the center of a cylindrical plasma column for the production of C 60 negative ions, resulting in the generation of alkali-fullerene plasma (Sato et al 1994). A voltage of V sub was applied to the substrate in the presence of a plasma space potential u s , controlling the collision energies such as E i [= e(u s -V sub )].…”

“…78b (Sato et al 2004(Sato et al , 2005. Since the helicon plasma leads to a higher energy density and a larger plasma volume, its PECVD reactor is attractive for the CNW synthesis with a high growth rate (Sato et al 2006). A capacitively coupled plasma (CCP) working as an independent plasma source for the CNW synthesis is commonly considered not to be suitable due to the relatively low electron density and electron energy, compared with the abovementioned high-density plasma sources (10 10 -10 13 cm -3 ).…”

“…With the use of these plasma sources, CNW growth can be realized using pure CH 4 as the feedstock gas, where CH 4 is expected to serve as both the carbon source and the a-C etchant. A helicon discharge, capable of exhibiting a high degree of molecule dissociation and producing plasmas with high-density (C 10 11 cm -3 ) electrons and highly energized ions at low pressures of 0.04-2 Pa, was adopted to synthesize CNWs using CH 4 without dilution (Sato et al 2006). As shown in Fig.…”