以聚碳硅烷为原料,通过1 200 ℃高温裂解工艺制备了碳化硅纳米线,并采用碳化硅纳米线作为高功率微波源用阴极材料, 进行了电子发射实验。结果表明：与天鹅绒阴极材料相比, 碳化硅纳米线具有更高的电子发射电流密度,在115 kV外加激励脉冲高压下,电子发射密度为23.7 kA/cm2,而天鹅绒材料为14.0 kA/cm2, 并具有更好的电子发射品质及更长的使用寿命。因此碳化硅纳米线作为高功率微波源用阴极,具有很好的应用潜力。

Experimental study on the electron emission of silicon carbide nanowires cathode samples fabricated by the pyrolysis of polycarbosilane at 1 200 ℃ was carried out. The results show that the silicon carbide nanowires cathode has higher electron emission current density, which is 23.7 kA/cm2 at the condition of 115 kV stimulation voltage and 10 mm distance between the cathode and anode, compared to 14.0 kA/cm2 for the velvet cathode. Also, it emits electron beams of better quality and has longer service life.