The Research About The Field Emission Performances Of Carbon Nanotube Arrays

Since the carbon nanotubes(CNTs) was discovered in 1991,the carbon nanotubes has attracted lots of attentions all over the word, it can be used in many domains because of its excellent mechanics, magnetics and electricity. The carbon nanotubes(CNTs) are composed of graphene sheets rolled into seamless hollow cylinders with diameters ranging from 1nm to about 50 nm and lengths reaching to several microns, the large aspect ratio of CNTs together with their hige chemical stability,thermal conductivity,and high mechamical strength are advantageous for field emitter applications.With the development of modern technology, carbon nanotubes have so many kinds of preparation methods,the technology of preparation and purification of carbon nanotubes trend to maturity in these years.All the above can tell us that carbon nanotubes is the best choice as field emission material.In this paper, at first,we analyzed the research and a large number of experiments about the field emission.basic to the field emission theory of the CNTs arrays.we discussed the preparation of CNTs array, we did the research on the field emission performances of the CNTs arrays that used the AAO template method, with the polymer as the carrier, we used the AAO template method in the prepartion of aligned CNTs arrays.Then, we did the research on the field emission performances of the CNTs arrays, such as the square carbon nanotubes array's and the hexagonal carbon nanotubes array's.By building the model of the CNTs arrays, we did caculations on the field emission performances of the CNTs arrays by solving the Laplace equation, we got the tip electric field and the field enhancement factor, at the same time, we could get the influences to the field emission performances such as the nanotube's shape, the distance between the nanotube's, the density of the carbon nanotube array and so on. Under the same conditions, comparing with the the hexagonal carbon nanotubes array's, the field enhancement factor of the square carbon nanotubes array's was lower than the hexagonal carbon nanotubes array's.We also did some caculations about the mass ratio between CNTs and the polymer in the CNTs arrays,providing a theoretical reference on the large-scale prepartion of aligned CNTs arrays.