Field Emission Properties of Multi-walled Carbon Nanotubes Grown Silicon Nanoporous Pillar Array

摘要

Multi-walled carbon nanotubes(CNTs)were grown on a silicon nanoporous pillar array(Si-NPA)by thermal chemical vapor deposition.Surface morphologies and microstructure of the resultant were studied by a field emission scanning electron microscope,Raman spectrum,transmission electron microscope,and high-resolution transmission electron microscopy.The composition of samples was determined by energy dispersive X-ray spectroscopy(EDS).The results showed that a great deal of CNTs,with diameter in the range of 20-70 nm,incorporated with Si-NPA and a large scale nest array of CNTs/Si-NPA(NACNT/Si-NPA)was formed.EDS analysis showed that the composition of carbon nanotubes was carbon.Field emission measurements showed that a current density of 5 mA/cm2 was obtained at an electric field of 4.26 V/urn,with a turn-on field of 1.3 V/mu m.The enhancement factor calculated according to the Fowler-Nordheim theory was ~11,000.This excellent field emission performance is attributed to the unique structure and morphology of NACNT/Si-NPA,especially the formation of a nest-shaped carbon nanotube array.A schematic drawing that illustrates the experimental configuration is given.These results indicate that NACNT/Si-NPA might be an ideal candidate cathode for potential applications in flat panel displays.