二硫化钼对二次电子倍增效应的抑制作用研究

Investigation on the suppression effect of multipactor by MoS_(2)

基于镀银铝合金材料的微波部件在高真空及大功率工作时容易产生二次电子倍增效应,引起噪声电平抬高,输出功率下降,导致微波部件失效。有效抑制二次电子倍增效应,对于空间微波部件的正常运行极为重要。二硫化钼不仅具有与石墨烯类似的结构,而且其带隙可调,具有出色的电学、光学等性能。通过水热法制备了二硫化钼,并将其涂覆在镀银铝合金材料的表面,研究了复合材料的二次电子发射特性。结果表明,合成的二硫化钼具有花瓣状的纳米结构,并可以显著降低镀银铝合金表面的二次电子发射系数至0.63,原因是三维形态的纳米花瓣状二硫化钼可在微波部件表面构建无数个“微陷阱”,使得二次电子被捕获的几率增加,从而降低其逸出材料表面的概率。表面涂覆二硫化钼的镀银铝合金材料可望用于提高大功率微波部件的阈值功率。

The microwave components based on silver-plated aluminum alloy are prone to produce multipactor effect in high vacuum and high power,which leads to noise level elevation and output power decline,and even microwave components failure.It is very important for the normal operation of space microwave components to effectively suppress the multipactor effect.The structure of MoS_(2) not only has a similar structure to graphene,but also has an adjustable band gap and excellent electronic and optical properties.In this paper,MoS_(2) prepared by hydrothermal method is coated on the surface of silver-plated aluminum alloy,and the secondary electron emission characteristics are studied.The results show that the synthesized MoS_(2) has nanostructures with petals shape,and can significantly reduce the secondary electron emission coefficient on the surface of the aluminum alloy silver plated to 0.63.The reason is that the three-dimensional nano-petal-shaped MoS_(2) can construct numerous“micro traps”on the surface of microwave components,which increases the probability of the secondary electron being captured and reduces the probability of its escaping from the material surface.The silver-plated aluminum alloy coated with nano-petal-shaped MoS_(2) can be used to improve the threshold power of high power microwave components.