A field emission-based carbon nanotube (CNT) luminescent light bulb has been fabricated by researchers in India and its luminescent properties, including lighting efficiency and voltage-current characteristics, have been investigated and compared with a conventional tungsten filament. The CNT light bulb is highly energy-efficient and shows excellent emission properties, such as low threshold, good emission stability and high luminescence.

Growing carbon nanotubes on tungsten electrodesThe interesting field emission properties of carbon nanotubes has led to a number of industrial applications – electron sources in X-ray analysers, nano-probes for AFMs and STMs, as well as field emitter devices such as nanotube lamps, flat-panel displays, TEM and SEM electron sources.

Further research should be performed to investigate the effects of doping, catalyst coating methods, growth methods and surface treatments on the luminescent properties of CNTs. It is also important to study how field emission depends on various device configurations including planar designs.

Device detailsSimulations should be carried out to understand the influence of various experimental and growth-related factors on the field emission of CNTs. Although the fundamental properties of CNTs are very favourable for use as field emission tips, these properties alone will not guarantee their success in this area. Perfect control of the catalytic CNT growth process is needed for the success of CNT field emitter technology.

The researchers presented their work in the journal http://nanotechweb.org/cws/article/lab/41756