Structure and Field Emission Properties of CNx Powders Synthesized by a Polymerization Process

The CNx powders were prepared by a polymerization process. The phase structure and bonding structure of the as-prepared powder were analyzed by X–ray diffraction and X–ray photoelectron spectroscopy, respectively. To prepare CNx field emission cathode, the CNx powders were coated onto Ti substrate using a suspension sedimentation method, followed by an annealing treatment to form a TiC phase. A three layer (Ti substrate–TiC joint network–CNx particles) structure model was proposed to explain the electron field emission properties for the as-prepared field emission cathode. The field emission measurement shows that for the as-prepared CNx cathode, the threshold electric field is 2.04 V/μm and the emission current density at 3.73 V/μm is 158 μA/cm.