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从BaO、SrO和CaO单晶的热电导、光电导、光电子发射和吸收光谱所测得的能级多而分散,不能得出一准确的能带图,这些情况说明表面能级比体内的更为重要。沉积在Ir(100)面上的BaO单晶膜的内外逸出功是单值的,它与用扫描低能电子探针所测得的三元炭酸盐的总逸出功的广泛分布有矛盾。这说明半导体模型并不能用来正确描述氧化物阴极。用Auger电子能谱仪发现二千小时寿命后涂层中氧多于碱土金属,但电子发射能力并不下降。这就否定了以氧缺位为施主的观点。然而超额钡仍然是发射电子的泉源,可以通过动态表面发射中心模型而与寿命中碱土金属下降统一起来。此模型提出了碱土金属氧化物原子团吸附有超额钡,可以有效地发射电子。这观点能解释许多用近代表面分析技术从氧化物阴极中观察到的现象。
From the thermal conductivities, photoconductivity, photoelectron emission and absorption spectra of BaO, SrO and CaO single crystals, the energy level is more and more dispersed, and an accurate band diagram can not be obtained, which shows that the surface energy level is more Important. The internal and external work function of the BaO single crystal film deposited on the Ir (100) surface is singular, in contradiction to the broad distribution of the total work function of the tribasic carbonates as measured by the scanning low energy electron probe . This shows that the semiconductor model can not be used to correctly describe the oxide cathode. The Auger electron spectrometer found that after two thousand hours of life, the coating had more oxygen than the alkaline earth metal, but the electron emission capacity did not decrease. This negates the idea of using oxygen vacancies as the donor. Excess barium, however, is still the source of electrons that can be emitted and can be integrated with the decline in the lifetime of alkaline earth metals through a dynamic surface emission center model. This model suggests that alkaline earth metal oxide radicals adsorb excess barium and emit electrons efficiently. This view can explain many of the phenomena observed with oxide cathodes using modern surface analysis techniques.