Direct synthesis of amorphous carbon nanotubes on Fe76Si9B10P5 glassy alloy particles

• A mass of amorphous carbon nanotubes have been synthesized.
• The Fe76Si9B10P5 particles were employed as both the catalyst and support.
• C2H2 and Ar were employed as carbon precursor and carrier gas, respectively.

A mass of amorphous carbon nanotubes (ACNTs) have been synthesized by chemical vapor deposition of C2H2 directly on Fe76Si9B10P5 glassy alloy particles without the addition of an external catalyst at 550 °C for 1 h. The ACNTs is 1–5 μm in length and 5–30 nm in diameter and has a Brunauer–Emmett–Teller surface area of 81.4 m2/g. Investigations on the ACNT growth process confirmed that the initial stage for appearance of isolated islands (α-Fe nanoparticles), which might be due to stress and surface breakup generated during high temperature CVD process, would be the decisive step for the ACNT growth.