Scandium‑tungsten (ScW) cathodes have garnered a lot of research attention due to their high emission current density. Herein, the cathode working environment is simulated by heating in a vacuum chamber, and scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) are used to study the surface morphology and chemical oxidation states in the temperature range of 25 °C to 1300 °C. The results reveal that the surface of the tungsten matrix is obviously recrystallized with increasing temperature. Moreover, the scandium oxide becomes globular and clear depressions or holes occur in the aggregation region of the rare-earth oxide at the grain boundaries. The work function is measured by the Richardson method at room temperature, 1000 °C, and 1300 °C and is found to be 2.77, 2.72, and 2.88 eV, respectively. The work function of the cathode initially decreases with increasing temperature, followed by a gradual increase. This is due to the fact that active substances such as scandium oxide are severely lost at high temperatures, destroying the surface structure of the sample. As the Sc/W value decreases, the rate of depletion of active material from the surface is greater than the rate of replenishment of material to the surface.

钪钨 (ScW) 阴极由于其高发射电流密度而引起了广泛的研究关注。在此，通过在真空室中加热模拟阴极工作环境，并使用扫描电子显微镜（SEM）和X射线光电子能谱（XPS）研究25°C温度范围内的表面形貌和化学氧化态至 1300 °C。结果表明，随着温度的升高，钨基体表面出现明显的再结晶。另外，氧化钪呈球状，在稀土氧化物的晶界凝聚区域产生明显的凹陷或空穴。功函数在室温、1000 °C 和 1300 °C 下通过 Richardson 方法测量，分别为 2.77、2.72 和 2.88 eV。阴极的功函数最初随着温度的升高而降低，然后逐渐增加。这是因为氧化钪等活性物质在高温下会严重流失，破坏样品的表面结构。随着 Sc/W 值的降低，活性材料从表面耗尽的速率大于材料补充到表面的速率。