Single-walled carbon nanotube growth from Ni catalyst particles under conventional growth conditions by alcohol catalytic chemical vapor deposition: in situ X-ray absorption fine structure study

Abstract

In situ X-ray absorption fine structure (XAFS) analysis was performed on Ni catalysts during single-walled carbon nanotube (SWCNT) growth by alcohol catalytic chemical vapor deposition (ACCVD). Ni catalysts were gradually reduced during the heating process and became metallic at the growth temperature (800 °C). With the addition of ethanol during SWCNT growth, Ni catalysts were slightly carbonized. Such a behavior was similar to that observed for Ir catalysts in our previous study, although Ni catalysts contained carbon composition with ~5%. The results of this study demonstrated the growth of SWCNTs from almost metallic catalysts under the conventional growth condition of ACCVD using Ni catalysts. Our result obtained by in situ XAFS analysis was consistent with the result of the atomistic computer simulations.