Carbon-nanotube-polymer nanocomposites for field-emission cathodes

The electron field-emission (FE) characteristics of functionalized single-walled carbon-nanotube (CNT)-polymer composites produced by solution processing are reported. It is shown that excellent electron emission can be obtained by using as little as 0.7% volume fraction of nanotubes in the composite. Furthermore by tailoring the nanotube concentration and type of polymer, improvements in the charge transfer through the composite can be obtained. The synthesis of well-dispersed randomly oriented nanotube-polymer composites by solution processing allows the development of CNT-based large area cathodes produced using a scalable technology. The relative insensitivity of the cathode's FE characteristics to the electrical conductivity of the composite is also discussed.