John_Stone Report This Comment Date: October 26, 2005 09:58AM
Figure 1. A SEM image of carbon nanotube based “buckypaper.” Bundles of
single-walled nanotubes may be seen on the surface of the buckypaper.
John_Stone Report This Comment Date: October 26, 2005 10:00AM
*Nanoscale Mass Transport and Carbon Nanotube Based Membranes* NASA
Carbon nanotube based membranes known as buckypaper may be used as filter media
for analytical mission instruments or implantable device support for astronaut
health monitoring.
Benefit
As an advanced membrane material, the buckypaper will have potential
applications in a variety of areas for manned space missions, ranging from fuel
cells to waste purification and air and water filtration.
Research Overview
We have constructed membranes out of CNTs as a material known as
"buckypaper" (Fig. 1) and have begun characterization of ion and gas
permeabilities of the buckypaper. The buckypaper displays a high surface area
(~450 m2/g) and an average pore size of 4-10 nm. Gas transport through
buckypaper displays unusual dependencies, (Fig. 2) with throughput dramatically
increasing as pressure is increased, in contradiction with common gas transport
models. Further characterization is necessary to ascertain whether the
buckypaper will behave as an effective gas separation media. Ion permeability
studies have shown the buckypaper to be more conducive as an ionic transport
media than it is for gas transport.
[
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