High brightness field emission from carbon nanosheets and back-gated devices

A 2D atomically thin nanostructure, carbon nanosheet, was synthesized via radio frequency plasma enhanced chemical vapor deposition. Carbon nanosheets are free-standing, and have flat surface morphologies, atomically thin edges, and defective graphitic structures. Field electron emission from carbon nanosheets was measured under diode mode. Carbon nanosheets samples have turn-on fields of 5-10 V/mum, and can yield a total emission current of 28 mA from an area of 8 times 8 mm
²
and an emission current density of ~2 mA/mm
²
from an area of 1 times 1 mm
²
. Back-gated triode devices using carbon nanosheets as cathode material were also designed, fabricated, and tested under triode mode. A total emission current of 1.3 mA was achieved from one single device.