Tuesday, October 13, 2009

US Patent 7601205 - CNT field emission air filter


Ionic air filters are common but see limited use on the small scale due to the high voltage necessary to charge air. This patent from IBM teaches a carbon nanotube ionization air filter which may improve the energy efficiency and lead to scalability of such devices. Claim 1 reads:

1. An electrostatic, airborne particulate precipitator comprising:

a housing unit;

a first conductive electrode located in said housing unit;

a second conductive electrode located in said housing unit at a distance from said first conductive electrode, said first and second conductive electrodes comprising poles of an electrostatic field; and

a carbon nanotube formed on said second conductive electrode, wherein said carbon nanotube comprises a shape sufficient to ionize gas in said housing unit.