Fluorescent single walled nanotube/silica composite materials

A process for preparing a fluorescent aerogel of carbon nanotubes and silica, comprising:

• preparing an aqueous suspension of single-walled carbon nanotubes and a surfactant;
• exposing the aqueous suspension to tetramethylorthosilicate and a base to form a first gel,
• exposing the first gel to methanol which replaces water in the first gel to form a second gel, and
• drying the gel with supercritical fluid to form an aerogel of single-walled carbon nanotubes and silica.

A process for preparing a fluorescent aerogel of carbon nanotubes and silica, comprising:

• preparing an aqueous suspension of single-walled carbon nanotubes and a surfactant;
• exposing the aqueous suspension to tetramethylorthosilicate vapor to form a first gel,
• exposing the first gel to methanol which replaces water in the first gel to form a second gel, and
• drying the second gel with supercritical fluid to form an aerogel of single-walled carbon nanotubes and silica.

A process for sensing a gas, comprising

• preparing an aqueous suspension of single-walled carbon nanotubes and a surfactant;
• exposing the aqueous suspension to tetramethylorthosilicate vapor to form a first gel,
• exposing the first gel to methanol which replaces water in the first gel to form a second gel, and
• drying the second gel with a supercritical fluid to form an aerogel of single-walled carbon nanotubes and silica,
• measuring the fluorescence from the single-walled carbon nanotubes in the aerogel in a first dielectric medium comprising a vacuum,
• changing the first dielectric medium to a second dielectric medium comprising a gas, and thereafter
• measuring the fluorescence from the single walled carbon nanotubes in a second dielectric medium, and then
• comparing the fluorescence from the aerogel in a vacuum with the fluorescence from the aerogel in a gas.

A process, for sensing a gas, comprising

• preparing an aqueous suspension of single-walled carbon nanotubes and a surfactant,
• exposing the aqueous suspension to tetramethylorthosilicate and a base to form a first gel,
• exposing the first gel to methanol which replaces water in the first gel to form a second gel, and
• drying the second gel with a supercritical fluid to form an aerogel of single-walled carbon nanotubes and silica,
• measuring the fluorescence from the single-walled carbon nanotubes in the aerogel in a first dielectric medium comprising a vacuum,
• changing the first dielectric medium to a second dielectric medium comprising a gas, and thereafter
• measuring the fluorescence from the single walled carbon nanotubes in a second dielectric medium, and then
• comparing the fluorescence from the aerogel in a vacuum with the fluorescence from the aerogel in a gas.