Carbon nanotube synthesis by feeding carbon and Fe precursor simultaneously

From the perspective of hetero-epitaxy, the diameter, wall number, and chirality of carbon nanotubes (CNT) should be dictated by the dimensions and facets of the catalyst nanoparticles (e.g., Fe, Ni, Co). Even without being able to control the catalyst facets, practitioners can synthesize mm-long single-walled CNTs from a pre-deposited film of catalyst less than 1-nm thick on a flat substrate. However, this approach is not optimal for CNT synthesis on nanoparticles, which is desirable for gas-phase catalysis applications. Chemical vapor deposition of Fe simultaneously with carbon feedstock offers a solution to this challenge.[1] By correlating the input Fe/C ratio with the CNT ensemble morphology and individual CNT structures, new insight into CNT formation can be obtained.

[1] T.-C. Shen, et al. Diamond & Related Materials 88, 230-236 (2018).