A transition metal substituted, amorphous mesoporous silica framework with
a high degree of structural order and a narrow pore diameter distribution
(.+-.0.15 nm FWHM) was synthesized and used for the templated growth of
single walled carbon nanotubes (SWNT). The physical properties of the
SWNT (diameter, diameter distribution, electronic characteristic) can be
controlled by the template pore size and the pore wall chemistry. The
SWNT can find applications, for example, in chemical sensors and
nanoscale electronic devices, such as transistors and crossbar switches.