  In this paper, we present a new, simple, robust and efficient technique to
decorate multi-wall carbon nanotubes (MWCNT) with metal nanoparticles. As case
studies, Au, Pt and Rh nanoparticles are grafted onto MWCNTs by spraying a
colloidal solution into the post-discharge of an atmospheric argon or
argon/oxygen RF plasma. The method that we introduce here is different from
those usually described in the literature, since the treatment is operated at
atmospheric pressure, allowing the realization in only one step of the surface
activation and the deposition processes. We demonstrate experimentally that the
addition of oxygen gas in the plasma increases significantly the amount of
grafted metal nanoparticles. Moreover, TEM pictures clearly show that the
grafted nanoparticles are well controlled in size.
