Carbon nanotube-enhanced performance of microplasma devices

Abstract

Incorporating multiwall carbon nanotubes (CNTs) directly into the cylindrical cathode of Ni screen/BN/Ni microplasma devices significantly improves all device performance parameters—operating and ignition voltages, as well as radiative efficiency. Having a cathode diameter of 200 μm, these devices exhibit operating voltages as much as 30 V (∼22%) lower than those required for an identical structure without CNTs. For Ne pressures of 100–300 Torr, ignition voltages are reduced by 14%–18% with the introduction of CNTs. In contrast, radiative efficiencies in the 300–800 nm spectral region are increased with CNTs by 6%–9% over the entire pressure range studied (200–600 Torr Ne). Voltage–current characteristics for two device configurations suggest that electrons generated within the cathode microcavity by CNT field emission are most effective in impacting device performance.