Growth of straight nanotubes with a cobalt–nickel catalyst by chemical vapor deposition

Abstract

In this letter, we report the catalytic synthesis of a large amount of straight carbon nanotubes using a transition-metal cobalt–nickel/zeolite catalyst. High-resolution transmission electron microscopy images show that they are well graphitized. Raman spectrum shows its peak at 1349 cm−1 (D band) is much weaker than that at 1582 cm−1 (G band). We believe that straight carbon nanotubes contain much less defects than curved nanotubes and might have potential applications in the future.

Microwave-assisted synthesis and magnetic properties of size-controlled CoNi/MWCNT nanocomposites

“…As important transition metal alloys, CoNi alloys have been widely used for decoration, corrosion resistance and magnetic recording devices, and catalysts, etc. [1][2][3][4][5]. In such applications, composition of CoNi alloy nanoparticles is considered the key characteristic affecting their magnetic properties and has been investigated by different methods [6][7][8][9].…”

Effect of TiAl-based interlayer on the surface morphology and adhesion of nanocrystalline diamond film deposited on WC–Co substrate by hot filament CVD

“…When the TiAl interlayer was adopted, however, clear peaks at 2697, 2940, and 3245 cm − 1 which correspond to the 2D, D + G and 2D′ peaks as reported in the carbon nanowalls [21] were observed. The peak observed at the 2697 cm −1 was also reported in carbon nanotube grown by CVD using a Co-containing catalyst [22]. The carbon-based phase detected at the delaminated region indicates that the delamination took place between interlayer and NCD film.…”

“…7(a) and (b) show the Raman spectra obtained at the delaminated regions of NCD-coated WC-6 wt.% Co substrates with (a) TiAl/TiAlN and (b) TiAl interlayers. For the NCD-coated WC-Co specimen with TiAl/TiAlN interlayer, a broad peak, which is believed to come from carbon-based phases such as graphite [21,22] and sp 2 -, sp 3 -bonded hydro-carbons [23], was observed in the region between 2500 and 3100 cm −1 . The broad peak was observed in all the NCD-coated WCCo specimens that we have prepared, irrespective of the adhesion of NCD film coated.…”

High-Yield Synthesis of Helical Carbon Nanofibers Using Iron Oxide Fine Powder as a Catalyst

“…Ni [7] High ability of carbon segregation Fe [19] Co [20], Pd [21] Promoter Cu [10], Sn [19] Low carbon segregation ability S [22] Synergetic effect with catalyst In [23] Keeps the distance between catalyst nanoparticles K [24] Controls the coil diameter…”