将第一性原理计算方法应用于空间大功率微波器件的低的二次电子发射系数材料的选材研究上。依据材料最大二次电子发射系数与功函数的关系，发现具有较低功函数的材料可能同时具有较低的最大二次电子发射系数值。以此为基础，对石墨烯结构覆盖的Ni （111）和Pd （111）表面形成的两种复合结构的功函数进行了计算，结果表明复合材料的功函数数值要明显的低于两种组分材料所具有的功函数数值。这一结果显示复合材料有可能具有较低的最大二次电子发射系数，为低的二次电子发射系数材料的选材的研究提供了新的思路和方法。
王筱杰
,
王大威
,
李永东
,
苌群峰
,
张楚贤
. 基于第一性原理计算的空间微波器件低的二次电子发射系数材料的研究[J]. 机械工程学报, 2018
, 54(9)
: 115
-120
.
DOI: 10.3901/JME.2018.09.115
First-principles computation is used in an attempt to identify materials with low secondary electron yield for high power microwave devices used in space. Based on the relation between the maximum secondary electron yield and the work function of materials, it is suggested that materials with lower work function may have lower maximum secondary electron yield. Following this lead, the work functions of two kinds of composite structures, which are formed by the coverage of the graphene structure on Ni (111) and Pd (111) surfaces, are calculated, which show that the composite material has a work function that is substaintially lower than either of its two components. Such result indicates that the composite material may have low maximum secondary electron yield. This approach provides new ideas for selecting materials with low secondary electron yield.
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