Enhanced field emission properties of carbon nanotubes by coating diamond-like carbon layer

Diamond-like carbon (DLC) coated carbon nanotubes (CNTs) can obtain dramatically enhanced properties of field emission compared to the pristine CNTs. After coated the DLC layer, the threshold field and current density can be improved remarkably. When the current density arrived at 5mA/cm², the electric field of DLC-coated CNTs was 1.88V/μm, much smaller than the value of pristine CNT arrays which was 3.03 V/μm. And compared to the pristine CNTs, the field emission current density from the DLC-coated CNTs was much larger at electric field 4.0V/μm. The current density of the DLC-coated CNT arrays was 80mA/cm², while that of the pristine CNT arrays was 51mA/cm².