Atomistic Observation of Structural Evolution during Magnesium Oxide Growth
journal contributionposted on 14.11.2016, 00:00 by Fan Cao, He Zheng, Shuangfeng Jia, Huihui Liu, Lei Li, Boyun Chen, Xi Liu, Shujing Wu, Huaping Sheng, Ru Xing, Dongshan Zhao, Jianbo Wang
Defects, such as dislocations, grain boundaries, and surfaces, play vital roles in the properties of nanocrystalline metal oxides. Thus, it is crucial to understand the structural evolution during the growth of metal oxides. In this work, atomistic observation of the structural dynamics in MgO grains during magnesium oxidation is realized by the in situ high resolution transmission electron microscopy. There are three major equivalent orientation relationships between MgO grains and Mg. Interestingly, our experiments reveal the grain rotation and grain boundary (GB) migration, resulting in the change of the orientation in MgO grains and the morphology of GBs. The dislocation activity that may mediate the GB migration and/or grain rotation is captured in MgO with high lattice strain/stress. Our results provide the atomic-scale structural evolution of the growth of passivating oxide layer on the Mg surface, which not only facilitate the development of metal oxide growth method but also provide a possible anticorrosion strategy.