Comparison of Fe/Al<tex>$_2$</tex>O<tex>$_3$</tex>and Fe, Co/Al<tex>$_2$</tex>O<tex>$_3$</tex>Catalysts Used for Production of Carbon Nanotubes From Acetylene by CCVD

Abstract

Characterization of iron containing alumina supported catalysts was performed by transmission electron microcopy (TEM), Mo/spl uml/ssbauer, and XPS spectroscopy during formation of multiwall carbon nanotubes from acetylene at 1000 K. TEM images showed that carbon fibers (outer diameter is around 20-40 nm) were generated on Fe/Al/sub 2/O/sub 3/ samples while on the bimetallic Fe,Co/Al/sub 2/O/sub 3/ carbon nanotubes with an average diameter of 8-12 nm were formed. XPS spectra revealed that Fe-Co alloy formed during the interaction of Fe,Co/Al/sub 2/O/sub 3/ and acetylene at 1000 K. The formation of the bimetallic alloy was proven by Mo/spl uml/ssbauer spectroscopy as well.