Role of sp(2) phase in field emission from nanostructured carbons

It is shown that sp(2) phase organization plays an important role in the fi eld emission from nanostructured carbons. Emission is found to depend on th e cluster size, anisotropy, and mesoscale bonding of the sp(2) phase, and t he electronic disorder. It is found by Raman spectroscopy that increasing t he size of sp(2) clusters in the 1-10 nm range improves emission. Anisotrop y in the sp(2) phase orientation can help or inhibit the emission. sp(2) cl usters embedded in the sp(3) matrix or electronic disorder induced by local ized defects oriented in the field direction can provide a local field enha ncement to facilitate the emission. (C) 2001 American Institute of Physics.