Nano carbon pipe composite field-emission source and manufacturing method thereof

The present invention relates to a nano carbon tube composite field emission source. It includes nano carbon tube membrane which is grown on the substrate and can be used as electronic field emission source. The described substrate is of conductive fibre braided rope or braided fabric, its fibre diameter range is 1-20 microns. The preparation method of said composite field emission source includes the following steps: under the condition of normal temperature and normal pressure utilizing phonochemical method to prepare nano carbon tube; adopting the processes of centrifugal separation, filtration, surface active ultrasonic dispersion, chemical corrosion, selective oxidation and ultrasonic etching, etc. to purify and shear nano carbon tube; then utilizing electrophoretic deposition process to make the purified and sheared nano carbon tube be firmly deposited on the conductive fibre braided rope or braided fabric so as to form the invented nano carbon tube composite field emission source.