Improving the FEM properties of MWCNTs by deposition ZnO for use in field nanoemitters

Array of nano-field emitters is used in devices such as vacuum tubes that are used in military equipment such as radars and electromagnetic weapons. These arrays have been realized based on carbon nanotubes (CNTs). In this article, carbon nanotube and zinc oxide (CNT–ZnO) nanocomposite were successfully synthesized with a different method. We have initially prepared multi-walled carbon nanotubes (MWCNTs) by the plasma enhanced chemical vapour deposition method. Alternatively, we used thermally physical vapour deposition for making thin Zn film to oxidize it later. Scanning electron microscopy and also Raman spectroscopy measurements of the prepared samples confirmed the presence of ZnO nano particles on the CNT bodies. By field emission (FE) measurements we found that ZnO deposited CNTs have a more efficient emissivity than that of CNTs alone.This composite can be used instead of cold cathode in vacuum tubes that work based on field emission properties. Before this, such tubes have been made with pure CNTs.