Field electron emission properties of the developed hierarchal MWCNT cathodes versus their AR. (a) Typical J-E curves of the field electron emitting hierarchal MWCNT cathodes with various pyramid AR values along with that of flat Si reference substrate. The inset shows a zoomed-in part of the J-E curves to compare their threshold field (TF). (b) Variation of the emitted current density at an applied field of 4 V/μm as a function of the AR of the Si pyramids.
Gautier et al. Nanoscale Research Letters 2014 9:55 doi:10.1186/1556-276X-9-55