Electron field emission properties of carbon nanotubes-deposited flexible film

A carbon nanotubes-deposited flexible film was prepared by electrophoretic method. A polyimide film coated with titanium was used as a cathode and a stainless steel plate as an anode, respectively. The two electrodes were placed into a bath with solvent consisting of grinded carbon nanotubes powder, Mg(NO3)2 6H2O and isopropyl alcohol (IPA). Mixed solution was stirred for about 2–4 h to assure the complete dissolution of Mg(NO3)2 6H2O and the dispersion of carbon nanotubes powder, dc electric field was applied to the two electrodes. The anode voltage was about 100 V. After 1–2 min, the carbon nanotubes powders were deposited on the polyimide film coated with titanium. The electron field emission properties of the prepared thin film were tested by a diode assembly. The turn-on field of the flexible film was about 2.96 V/mm. The current density of the flexible film was about 200 mA/cm2 at an electric field of 5.9 V/mm. The morphology and structure of the carbon nanotubes-deposited flexible film were analyzed by scanning electron microscope (SEM) and Raman spectroscopy. The experimental results indicate that this film could be a promising material applicable to cold cathodes