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选用片状样品考察ＭｏＬａ２Ｏ３ 阴极激活过程， 侧重分析Ｌａ 的存在状态和变化对热发射的影响。对高温ＸＰＳ实验结果的分析证实， 激活过程Ｌａ 的化学价态发生了改变， 伴随大量晶格氧的分离，Ｌａ２Ｏ３变成了缺氧化合物ＬａＯｘ（ｘ＜３／２） ， 即形成了超额的金属Ｌａ； 修正的Ａｕｇｅｒ 参数等变化趋势与上述相符。ＬａＯｘ 具有较低的逸出功是由于氧缺位的存在， 氧缺位对电子发射起到积极影响。激活过程促使Ｌａ，Ｏ离子的价电子态密度增加， 配位不饱和的Ｌａ 离子外层６ ｓ 高能价电子易形成电子发射， 即这一变化过程对热电子发射具有积极作用。
Flake samples were selected to investigate the activation of Mo-La2O3 cathode, focusing on the analysis of the existence of La and the impact of changes on the thermal emission. Analysis of the results of high temperature XPS experiments confirmed that the chemical valence of La changed during the activation process. With the separation of a large amount of lattice oxygen, La2O3 became the anoxic compound LaOx (x <3/2), that is, the excess metal was formed La; The revised Auger parameters and other trends consistent with the above. The lower work function of LaOx is due to the absence of oxygen, which has a positive effect on electron emission. Activation led to the increase of valence electron density of La and O ions. Electron emission was easily formed by the 6 s high energy valence electrons from the outer layer of the coordination La ion. The change process had a positive effect on the thermionic emission.