Viscous State Effect on the Activity of Fe Nanocatalysts

Abstract

Many applications of nanotubes and nanowires require controlled bottom up engineering of these nanostructures In catalytic chemical vapor deposition, the thermo kinetic state of the nanocatalysts near the melting point is one of the factors ruling the morphology of the grown structures We present theoretical and experimental evidence of a viscous state for nanoparticles near their melting point The state exists ove a temperatuer range scaling inversely with the catalyst size, resulting in enhanced self diffusion and fluidity across the solid- liquid transformation The overall effect of this phenomenon on the growth of nanotubes is that for a given temperature, smaller nanoparticles have a larger reaction rate than larger catalyts