Environmental Engineering Reference
In-Depth Information
9.7.1
Titanium-Decorated Carbon Nanotube Cloth
A solution seems to exist that builds upon aspects of the two previous figures.
Titanium atoms directly bridging two carbon atoms can decorate graphene planes,
either as sheets or as nanotubes. Durgun et al. [118a] and also Lee et al. [119] have
previously predicted rather similar hydrogen storage results based on titanium
atoms bridging carbon sites in carbon nanotubes. Carbon nanotubes can be
formed as a sheet or cloth that
is strong,
lightweight, and electrically
conductive [120].
It is assumed that such a cloth can be decorated with a high density of Ti atoms,
bridging carbon sites as in the cases above, to serve as a nanoporous storage medium
for hydrogen. Ti deposition could be accomplished on the cloth in a CVD reactor.
Hydrogen storage with desorption by electrical heating could be based on such a
carbon nanotube sheet, as indicated in Figure 9.9. This
gure shows a carbon
nanotube cloth operating as a planar incandescent lamp, to illustrate the ability to
control its temperature by simple passage of current through the cloth.
Figure 9.9 Uniform incandescent light
radiation demonstrates uniform electrical Joule
heating of carbon nanotube cloth, dimensions
16mm12mm [120]. This sheet of multiwall
carbon nanotubes is free-standing, attached to
vertical supports that serve as electrical
contacts. The sheet temperature was adjustable
over the range 1000
-
1600 K. The low mass of
the nanotube sheet resulted in a time constant
for temperature change on the order of 0.1ms.
