Formation of gold nanoparticles on multiwalled carbon nanotubes by thermal evaporation

Multiwalled carbon nanotubes (MWCNTs) were grown on W substrates by chemical vapor deposition and modified with Au nanoparticles by thermal evaporation. The resulting hybrid structures were investigated by TEM to determine the effects of evaporation rate, nominal film thickness, and substrate temperature on the nanoparticle size and distribution. The results demonstrate that as-grown MWCNTs can be used as a support for well distributed Au nanoparticles, with the size and distribution on the carbon nanotubes being primarily influenced by the nominal film thickness. The observed structures ranged from small 4 nm diameter spherical particles to 150 nm long wire-like structures. Depositions with substrates at 25 °C and 400 °C resulted in similar particle structures, except for the highest amount of deposited Au.