Room temperature ionic liquids were adsorbed on the surface of the multiwalled carbon nanotubes
(MWCNTs) by electrostatic interaction between carboxyl groups on the chemically oxidized
MWCNTs surface and room temperature ionic liquids. The cations of ionic liquids and carboxyl
groups on the carbon nanotube surface are put into a one-to-one correspondence by the
electrostatic interaction. Negatively charged 15 nm gold nanoparticles are subsequently anchored
to the surface of the MWCNTs through the electrostatic interaction between the ionic liquids and
the gold nanoparticles. Gold nanoparticles are selectively attached to chemically functionalized
surface sites of carbon nanotubes. This approach provides an efficient method to attach other
nanostructures to carbon nanotubes and can be used as an illustrative detection of the functional
groups on carbon nanotube surfaces.
