Abstract: An emission cathode having a surface formed of carbon fiber and a layer of carbon nanotubes attached to the surface. The carbon nanotubes are generally parallel to each other and oriented longitudinally in a predetermined direction relative to the surface.

Abstract: A method of forming a microporous fluoropolymer membrane, comprising the steps of: irradiating a sheet of fluoropolymer at a dosage level below the rupture energy of the carbon-to-fluorine (C—F) bonds of the fluoropolymer, but sufficient to rupture carbon-to-carbon (C—C) bonds; and exposing the sheet of fluoropolymer to an etchant for a period of time sufficient to etch away disrupted atoms and molecules, wherein continuous micropassages are formed through the sheet.