Lazarov Vlado K, Chambers Scott A, Gajdardziska-Josifovska Marija
Department of Physics, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53211, USA.
Phys Rev Lett. 2003 May 30;90(21):216108. doi: 10.1103/PhysRevLett.90.216108.
In situ x-ray photoelectron spectroscopy and ex situ transmission electron microscopy and diffraction studies of a model Fe3O4(111)/MgO(111) polar oxide interface exclude stabilization by interface faceting, reconstruction, or by formation of a continuous interfacial layer with altered stoichiometry, and uncover stabilization by dominant formation of metallic Fe(110) nanocrystals. The iron nanocrystals nucleate both at the interface and within the magnetite film and grow in a Nishiyama-Wasserman orientation relationship with a bimodal size distribution related to twinning. Minority magnetite nanocrystals were also observed, growing in the less polar (100) orientation than the magnetite (111) film. Electron transfer and bond hybridization mechanisms are likely at the metal/oxide and oxide/oxide interfaces and remain to be explored.
对Fe3O4(111)/MgO(111)极性氧化物界面模型进行的原位X射线光电子能谱、非原位透射电子显微镜和衍射研究排除了界面刻面、重构或形成具有化学计量比改变的连续界面层所导致的稳定性，并揭示了金属Fe(110)纳米晶体的主导形成导致的稳定性。铁纳米晶体在界面处和磁铁矿薄膜内均形核，并以西山-瓦瑟曼取向关系生长，具有与孪晶相关的双峰尺寸分布。还观察到少数磁铁矿纳米晶体，其生长方向比磁铁矿(111)薄膜的极性小(100)。电子转移和键杂化机制可能存在于金属/氧化物和氧化物/氧化物界面，有待进一步探索。
