PNNL-13501 - Pacific Northwest National Laboratory

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PVF on CNTs
PVF on carbon cloth
Time,
Figure 4. Hydrogen concentration determined using nuclear
reaction analysis
(a)
0.0
0 50 100 150 200 250
Time,
Figure 3. (a) Integrated charge passed from cyclic
voltammogram of polyvinylferrocene-coated carbon
nanotube thin film measured in 0.5 M NaNO 3 at 5 mV/sec.
Time = 0 corresponds to beginning of the potential scan. (b)
Same as (a) but normalized to the maximum charge passed.
(b)
reports on the hydrogen content of carbon nanotubes that
have undergone similar treatments. Because this
technique is a direct spectroscopic measure of hydrogen
in carbon nanotubes, it provides an unambiguous measure
of hydrogen content. The technique is especially useful
for studying hydrogen uptake and release by means of
pressure swings.
Summary and Conclusion
We have grown aligned carbon nanotubes over
macroscopic domains (10s of µms). Current limitations
in the size of crack-free domains are believed to be caused
by cracks that developed on the precursor porous silica
film. We have shown that surfaces of carbon nanotubes
can be easily functionalized with metal nanoparticles and
polymers. Platinum nanoparticles were electrochemically
deposited on carbon nanotube thin films. Carbon
nanotube films coated with electroactive polymers show
an increase in the electrochemically active area with
minimal mass transport limitations. An ion beam
technique based on nuclear reaction analysis was
successfully employed to measure the hydrogen content
of thin carbon nanotube films.
Reference
Li WZ, SS Xie, LX Qian, BH Chang, BS Zou, WY Zhou,
RA Zhao, and G Wang. 1996. “Large-scale synthesis of
aligned carbon nanotubes.” Science 274:1701.
Presentation
“Synthesis and Properties of Functionalized Carbon
Nanotube Composites.” Presented at Pacifichem 2000,
December 14 - 19, 2000, Honolulu, Hawaii.
Materials Science and Technology 305