目的 设计一种利用常见的铅笔芯和碳纳米管复合的全碳材料点状场发射器件，通过石墨烯填充，增强场发射性能。方法 导电玻璃作为阳极，铅笔芯与碳纳米管复合构成发射子，锡底座固定铅笔芯，并利用导电胶与导电玻璃粘接组成阴极。通过比较纯碳纳米管与不同浓度石墨烯的场发射性能，找到效果最好的填充石墨烯浓度。结合扫描电镜表征结果，对石墨烯填充增强场发射性能的原因进行解释。结果 实现了全碳材料点状场发射器件的制备及场发射性能的优化，发现7%的石墨烯浆料制备的器件场发射性能最好，得到的点状场发射阴极的阈值电场为1.05 V/μm，场发射增强因子高达13509，最大电流0.75 mA。结论 点状场发射器件拥有更好的聚焦性、更低的开启场强以及更大的场发射电流密度，在制作X射线源和微波器件方面具有较高的应用价值。

The work aims to design a point field emission device with common pencil lead and carbon nanotubes, so as to enhance field emission performance through filling graphene. ITO glass was used as anode and pencil lead and carbon nanotubes formed the emission terminal. Tin base was used to fix the pencil lead and conducting resin and ITO glass were adhered to form the cathode. By comparing the field emission performance of pure carbon nanotubes and carbon nanotubes with different concentrations of graphene, the best concentration of graphene was found. SEM image was adopted to explain the reason why graphene enhanced field emission performance. All-carbon materials point field emission device was prepared and field emission performance was optimized. The point-type emitter with 7% graphene showed an excellent field emission performance with a low turn-on electric field of 1.05 V/μm, field enhancement factor of 13509 and maximum emission current of 0.75 mA. Point-type field emission device has better focusing, lower on-field strength and higher field emission current density, and has higher application value in the manufacture of X-ray sources and microwave devices.