Abstract Magnesium oxide is of critical importance for the properties of magnesium alloys designed for solid state storage of hydrogen. The oxidation of Mg was investigated by in-situ transmission electron microscopy under vacuum conditions and 105 Pa of H2 with a special emphasis on the influence of grain boundaries. In agreement with thermodynamic predictions, nucleation and growth of MgO was observed in both conditions, but the mechanisms and the corresponding kinetic are very different. Under vacuum it is assisted by Mg sublimation and relatively fast, while under H2 the oxidation proceeds slowly along grain boundaries that act as nucleation sites.

中文翻译：

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氢对细晶粒镁氧化机制影响的原位透射电子显微镜研究

摘要 氧化镁对于设计用于固态储氢的镁合金的性能至关重要。通过原位透射电子显微镜在真空条件和 105 Pa 的 H2 下研究 Mg 的氧化，特别强调晶界的影响。与热力学预测一致，在两种条件下均观察到 MgO 的成核和生长，但机制和相应的动力学非常不同。在真空条件下，它受到镁升华的帮助并且相对较快，而在 H2 下，氧化沿着充当成核点的晶界缓慢进行。