Dynamic behavior of carbon nanotube field emitters observed by in situ transmission electron microscopy

Improvement of emission reliability of carbon nanotube emitters by electrical conditioning

“…The corresponding A values of CNT emitter before and after aging treatment were dramatically increased from 10 -17 to 10 -12 m 2 ranges (without the 20 h aged one). From these results, it is suggested that the increased emitting area is attributed to removal of weak and extremely sharp CNTs from their local positions due to resistive heating of the individual tube which provide instability during the electrical aging, resulting in the improvement of half-lifetime [11,16].…”

“…The high emission current (electric field) induced structural degradation and failure of SCWNTs and Table 1 The field emission characteristics and factors of CNT emitter depending on electrical aging conditions. E to (V/μm) MWCNTs during field emission have been reported by the insitu observation [8][9][10][11].…”

“…Previously, the stability and reliability of CNT emitters was found to be strongly dependent on the vacuum level and residual gas [6,7]. Gradual degradation and abrupt failure of CNT emitter under the extreme field emission condition have been also reported [8][9][10][11]. It is expected that wide band gap materials coating and post-treatments can enhance the environmental stability and reliability of CNT emitter [12,13].…”

Operation of a Carbon Nanotube Field Emitter Array in a Hall Effect Thruster Plume Environment

“…These changes in position could be due to HET exposure or to handling during the installation and removal of the distal sample from the thruster cathode array. Previous studies report motion of CNTs under the presence of electric fields and during FE [18]- [23]. While this CNT cannot have performed FE, it was exposed to the HET plasma and the electric field variations present at its length scale could be responsible for this observed behavior.…”

Enhancement of field emission properties of graphite flakes by producing carbon nanotubes on above using thermal chemical vapor deposition

“…In our previous study, the graphite flake was chosen to replace the CNT which cannot abide by the high-electron current pass through itself [17] for its higher electronic and thermal stability In order to improve the field emission properties of the graphite flakes, the carbon nanotubes (CNTs) are produced on above without the metallic catalyst using mixtures of C 2 H 2 and H 2 gases by thermal chemical vapor deposition. We spin the graphite solution on the silicon wafer and dry it, then synthesize the CNTs on the graphite flakes.…”