Production of single-walled carbon nanotube grids
A method of forming a nanotube grid includes placing a plurality of catalyst nanoparticles on a grid framework, contacting the catalyst nanoparticles with a gas mixture that includes hydrogen and a carbon source in a reaction chamber, forming an activated gas from the gas mixture, heating the grid framework and activated gas, and controlling a growth time to generate a single-wall carbon nanotube array radially about the grid framework. A filter membrane may be produced by this method.
1. A method comprising:
placing a plurality of catalyst nanoparticles on a metal grid framework;
wherein the catalyst nanoparticles comprise iron, and
wherein the metal grid framework comprises aluminum and a plurality of individual unit cells;
forming an activated gas mixture,
wherein the activated gas mixture comprises atomic hydrogen and a carbon source,
wherein the atomic hydrogen in the activated gas mixture is formed by exposing molecular hydrogen to a hot filament, and
wherein the hot filament is at a temperature of greater than about 2,000° C.;
contacting the catalyst nanoparticles on the metal grid framework with the activated gas mixture,
wherein the contacting step occurs in a reaction chamber;
heating the metal grid framework and the activated gas mixture; and
controlling a growth time to generate a single-wall carbon nanotube array radially about the metal grid framework.
2. The method of claim 1 , wherein the catalyst nanoparticles range in size from about 0.5 nanometers to about 10 nanometers.
3. The method of claim 1 , wherein each of the plurality of individual unit cells have dimensions ranging from about 100 nm to about 1000 nm.
4. The method of claim 1 , wherein the carbon source comprises a hydrocarbon.
5. The method of claim 4 , wherein the hydrocarbon is selected from the group consisting of acetylene and ethylene.
6. The method of claim 1 , wherein the activated gas mixture and the metal grid framework are heated in the reaction chamber to a temperature sufficient to produce single-walled carbon nanotubes.
7. The method of claim 1 , wherein a pressure of the reaction chamber is below atmospheric pressure.
8. The method of claim 1 , wherein controlling the growth time affects a pore size of the metal grid framework.
9. The method of claim 1 , wherein each of the plurality of individual unit cells have dimensions ranging from about 1 micron to about 500 microns.