Carbon Nanotubes Cathode of Field Emission Lamp Prepared by Electrophoretic Deposition

Field emission lamp is a kind of green and low energy loss light source. Carbon nanotube cathode of field emission lamp was prepared by electrophoretic deposition. Two types of solute salt were added in electrophoretic solution separately, which were used to prepare two types of carbon nanotubes films on identical aluminum sheets by electrophoretic deposition method. Scanning electron microscopy(SEM) were used to observe the surface morphology of the films. The field emission properties of the films were tested by using a diode structure. The turn-on field of the film deposited with CsNO3 / Ca(NO3)2 4H2O solution was 0.7 V/μm. The current density of the film was about 4000 mA/cm2 at an electric field of 1.8 V/μm. While corresponding data by using Mg(NO3)2 6H2O solution was 0.8 V/μm and 3800 mA/cm2. It is concluded that the field emission properties of the deposited film cathode by using CsNO3/ Ca(NO3)2 4H2O solution better than that using Mg(NO3)2 6H2O solution.