We present a chemical vapor deposition(CVD)method for the growth of uniform single-walled carbon nanotube(SWNT)arrays on a stable temperature(ST)-cut single crystal quartz substrate using a mixture of methanol and ethanol as carbon source.It is found that introducing methanol during the growth can improve the density and the length of the well-aligned SWNTs in the arrays as well as increase the SWNT/quartz interaction.Obvious“up-shifts”of G-band frequencies in the Raman spectra have been found for the aligned SWNTs.A well-designed control experiment shows that the G-band“up-shifts”originate from the strong interaction between SWNTs and the quartz substrate.It is believed that exploring this interaction will help to elucidate the growth mechanism;ultimately,this will help realize the promise of controlling the chirality of SWNTs.
Lei DingWeiwei ZhouThomas P.McNicholasJinyong WangHaibin ChuYan LiJie Liu
Using carbon nanotubes as nanobarriers,the growth of single-walled carbon nanotubes(SWNTs)on a quartz surface can be terminated.First,carbon nanotube nanobarriers were grown on a quartz surface by the gas ow-directed growth mode.Then,the SWNTs were grown on the quartz surface via the lattice-oriented growth mode,in which growth of SWNTs can be terminated by hitting the nanotube nanobarriers.Moreover,using the carbon nanotube nanobarrier as a marker,the mechanism of the growth of SWNTs on the quartz surface can be studied;a base-growth mechanism is indicated.Based on this termination process and the base-growth mechanism,SWNT arrays with controlled lengths can be grown on a quartz surface by xing the sites of bothcatalysts and nanobarriers.