Field emission from multiwall carbon nanotubes on paper substrates

The authors report extremely low electron field emission thresholds from acid oxidized multiwall carbon nanotubes deposited on paper substrates by dip coating in an aqueous nanotube ink. Using paper substrates of differing surface roughness, field emission threshold fields ranging from 0.8 to 11.6 V/mu m were observed, varying in an approximate inverse linear log relationship with the surface roughness of the underlying paper substrate. This study shows how field emission from supported nanotube films can be tailored via the morphology of the scaffold substrate, and how these composite electrodes can be straightforwardly fabricated on cheap, flexible substrates. (c) 2007 American Institute of Physics.