*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.

[www.nasa.gov]