The growth of carbon nanotubes such as single-walled carbon nanotubes
(SWNTs) is achieved using a catalyst and carbon feedstock gas, with the
catalyst being delivered using an approach for relatively clean delivery
and placement thereof. In one example embodiment, nanoparticles are
deposited from solution onto a substrate, and the substrate is
subsequently heated to form catalyst material from the nanoparticles. A
carbon nanotube is then grown from the catalyst material, using the
catalyst material to catalyze a reaction that is used to grow the carbon
nanotube. In one implementation, hydroxylamine is used in the deposition
of nanoparticles of a catalyst precursor material from aqueous
iron-containing solutions onto an SiO.sub.2 substrate. The nanoparticles
are heated and used to form catalyst material on the SiO.sub.2 substrate,
which is used in the subsequent growth of carbon nanotubes via the
introduction of carbon-containing gas to the nanoparticles.