Controlled growth of carbon nanotubes on the high surface area magnesium oxide by RF CCVD

PHYS 406

Yang Xu, yxxu@ualr.edu1, Alexandru S. Biris, asbiris@ualr.edu2, Zhongrui Li, zxli3@ualr.edu2, Enkeleda Dervishi, exdervishi@ualr.edu1, Viney Saini, vxsaini@ualr.edu1, Olumide D. Oshin3, Alexandru R. Biris, biris@oc1.itim-cj.ro4, and Dan Lupu, lupu@oc1.itim-cj.ro4. (1) Applied Science dept, Nanotechnology Center, University of Arkansas at Little Rock, 2801 S. University Ave, Little Rock, AR 72204, (2) Applied Science Department, Nanotechnology Center, University of Arkansas at Little Rock, 2801 South University Avenue, Little Rock, AR 72204, (3) Nanotechnology Center and Applied Science Department, University of Arkansas at Little Rock, 2801 S. University Ave, Little Rock, AR 72204, (4) National Institute for Research and Development of Isotopic and Molecular Technologies, P.O. Box 700, R-400293, Cluj Napoca, R 3400, Romania
Low cost and high surface area of mesoporous magnesia was synthesized by thermal decomposition of the hydrate magnesium oxalate. Not only the reactants magnesium acetate and oxalate acid but also the calcinations condition is believed to play an important role on the forming of MgO with the surface area as high as 380m2/g. Here, Single wall nanotubes (SWNTs) have been grown on Fe/Co-loaded mesoporous MgO catalyst from methane at the optimum temperature of 850℃ by RF (Radio Frequency) induced CCVD method. The SWNT yield and diameter distribution can be varied by controlling the process parameters. One step synthesis without pre-reducing catalyst was the most efficient way to grow SWNTs on the mesoporous MgO. Once methane acted as the reducer and carbon source at the same time, it will reduce the possibility for particles sintering on the porous surfaces. We found the wall numbers of CNTs were dependent on the pretreatment for the catalysts such as calcinations temperature, time and flowing gas rate because these factors would change the metallic particle size. The present results would help us to develop a large-scale synthesis on support materials or controlled growth of CNTs with different number of walls.
 

PHYS Poster Session - Nanostructured Materials and Nanophotonics
7:30 PM-10:00 PM, Wednesday, April 9, 2008 Morial Convention Center -- Hall A, Poster

Division of Physical Chemistry

The 235th ACS National Meeting, New Orleans, LA, April 6-10, 2008