Super-low turn-on and threshold electric fields of plasma-treated partly Fe-filled carbon nanotube films

Field emission properties of partly Fe-filled carbon nanotubes (FCNTs) treated with different plasmas have been studied. Super low turn-on (0.24 V/μm) and threshold (0.6 V/μm) electric fields are identified upon nitrogen plasma treatment for 60 min. The field-enhancement factor, as high as 4.8 × 104, can be attributed to the plasma-induced structural defects and the unique characteristics of thin walled FCNTs with filled Fe nanowires. A model has been proposed to understand the effects of plasma on the CNTs.