▎ 摘　　要

NOVELTY - A nitrogen-doped reducing graphene oxide field emitting cathode is prepared by mixing ethyl cellulose and terpineol, stirring using magnetic controller to obtain organic adhesive, and mixing graphene oxide and organic adhesive to obtain graphene oxide paste; ultrasonically dispersing and dissolving to form graphene oxide dispersion, using one end of graphite rod to dip dispersion, drying graphite rod, placing dried graphite rod having one end of graphene oxide and chitosan in quartz tube, putting in tubular furnace, putting quartz tube in small tube filled with chitosan, closing one end, placing graphite rod with one end with graphene oxide at closed end of quartz tube, placing small tube filled with chitosan at opening end of quartz tube and opposite to graphite rod, and introducing argon gas; and chitosan heating and decomposing, reacting with graphene oxide for nitrogen atom doping, placing graphite rod in quartz boat, and reduction reacting. USE - The method is used for preparing nitrogen-doped reducing graphene oxide field emitting cathode for field emission device, field emission flat panel display, field emission light source and vacuum electronic device. ADVANTAGE - The product reduces work function and starting voltage of field emission, introduces more emitting sites on graphene surface, improves emission enhancement factor. DETAILED DESCRIPTION - A nitrogen-doped reducing graphene oxide field emitting cathode is prepared by: (A) mixing ethyl cellulose and terpineol at mass ratio of 1:5-20 in water bath at 60-100 degrees C for 2-6 hours, stirring using magnetic controller for 2-4 hours to obtain organic adhesive, and mixing graphene oxide and organic adhesive with mass ratio of 1:10-20 to obtain graphene oxide paste; (B) ultrasonically dispersing and dissolving for 0.5-2 hours to form graphene oxide dispersion, using one end of graphite rod to dip dispersion, drying graphite rod in vacuum environment at 60-120 degrees C for 30 minutes, placing dried graphite rod having one end of graphene oxide and chitosan in quartz tube, putting in tubular furnace, putting quartz tube in small tube filled with chitosan, closing one end, placing graphite rod with one end with graphene oxide at closed end of quartz tube, placing small tube filled with chitosan at opening end of quartz tube and opposite to graphite rod, and introducing argon gas at 300-800 degrees C; and (C) chitosan heating and decomposing to generate nitrogen-containing product, reacting with graphene oxide for nitrogen atom doping, placing graphite rod in quartz boat, putting into 600-1000 degrees C high temperature furnace, introducing 5-100 standard cubic centimeters per minute (sccm) hydrogen, performing reduction reaction under hydrogen atmosphere of 5-100 Pa. The flow rate of argon gas is 10-200 sccm. The chitosan is powder and has mass of 0.1-5 g.