Improving the Performance of Field Electron Emission from Carbon Fiber Emitters with an Epoxy Resin 478 Coating Layer

The aim of this research is to investigate the differences in behavior and characteristics of electron beams emitted from carbon fiber tips before and after coating their surfaces with a thin layer of epoxy resin 478. Several field electron emission characteristics have been investigated measured under high vacuum (HV) conditions, before and after coating by dielectric materials. The measurements recorded involve current-voltage (I–V) characteristics) as well as spatial current distributions (electron emission images). Furthermore, the surface morphology and chemical composition of the emitters were thoroughly examined utilising a Scanning Electron Microscope with Energy-Dispersive X-ray Spectroscopy (SEM-EDS). The results show significant variations in the emission mechanisms between clean and composite emitters. In particular, the emitters coated with epoxy resin 478 demonstrated an important improvement in the emission characteristics, such as enhanced emission current density and the stability of the emitted current. These results demonstrate how well the insulating layer works to enhance the efficiency of electron emitters fabricated from carbon fiber.