Enhanced field-emission capacity by density control of a CNT cathode using post-plasma treatment

The effects of hydrogen plasma treatment on surface morphologies and field emission performance of vertically aligned multi-walled carbon nanotubes were investigated. The hydrogen plasma treatment of vertically aligned multi-walled carbon nanotubes induces changing surface morphologies from flat surface to sharp conical shapes according to the plasma treatment time. The morphological changes owing to plasma treatment enhances field emission performance of vertically aligned carbon nanotubes so that the current density and field enhancement factor were considerably improved compared to those of as-grown one.