Fabrication and field emission properties of CNT cathodes on thin-film substrate electrodes

The carbon nanotube(CNT) field emission cathodes based on different thin film substrate electrodes are prepared by electrophoretic deposition(EPD).The morphologies of CNT cathodes after being sintered under high temperature are observed by field emission scanning electron microscope(FESEM),which show that CNTs are uniformly distributed on the substrate electrodes.The field emission properties of CNT cathodes are influenced by substrate electrode materials obviously.The turn-on electric field of the CNT cathode on CrCuCr thin film is 0.51 V/μm,and that on ITO transparent thin film is 0.81 V/μm.When the anode current density is 0.7 mA/cm2,the brightness luminosity of CrCuCr-CNT cathode is 995 cd/m2,and that of ITO-CNT cathode is 834 cd/m2.It can be indicated that the property of CNT cathode on CrCuCr thin film is quite well,for its turn-on electric field is lower and its current density can be 0.9 mA/cm2 stably.At last,the field emission properties are analyzed by the model of double-potential barrier for the contact between CNT and the substrate electrodes.