Abstract Submitted to the NANOTUBE'02 Workshop:

Recently we have succeeded in the growth of well-aligned two-dimensional carbon sheets (dubbed carbon nanowalls) on foreign substrates [1]. In this paper, we will report the detailed formation mechanism of carbon nanowalls as well as the application of nanowalls as templates for the fabrication of other types of nanostructured materials. The key to growing carbon nanowalls was found to be the existence of both a vertical and a lateral electrical field in the vicinity of the growth sites. This has been confirmed by both controlling the field globally and locally. The carbon nanowalls have been grown both uniformly and selectively on various substrates which include Si, SiO₂, sapphire, glass, Cu, stainless steel, GaAs, and anodized Al. The nanowalls exhibit a lateral size ranging from sub-micron to a few microns and a thickness of a few nanometers. The large surface area may make the nanowalls a promising candidate for various applications which require the use of porous carbons. To this end, we have grown various types of nanostructured materials on the carbon nanowalls. These include Ni, NiFe, NiFeCo, Au, Cu, ZnO, TiO₂, SiO_x, AlO_x, and SiN_x. Most of the metallic materials formed as nanoparticles on the nanowall surfaces, while the oxides covered the nanowalls conformally.

[1] Y.H. Wu and T.C. Chong, paper presented at the MRS 2001 Spring Meeting, abstract No. W8.3, San Francisco, USA, April 16-20, 2001; Y.H. Wu, P.W. Qiao, T.C. Chong, Z.X. Shen, Adv.Mater.2002,14, No.1, 64; Y.H. Wu, B.J. Yang, Nanoletters, Articles ASAP, released on January 24, 2002.