Yuichi Ikuhara, Grain Boundary Geometry, Structural Units and Segregation in Oxides

Yuichi Ikuhara1,2,3

1) Institute of Engineering Innovation, The University of Tokyo, Tokyo, 113-8656, Japan

2) Nanostructures Research Laboratory, Japan Fine Ceramics Center, Nagoya, 456-8587, Japan

3) WPI-AIMR Research Center, Tohoku University, Sendai, 980-8577, Japan


Grain boundary (GB) atomic structures are dependent on the GB characters such as misorientation angle and GB planes. In addition, GB structures are also influenced by the segregated dopants and vacancies to form the relaxed structural units along the GBs. It is therefore needed to investigate the sites of vacancies and dopants segregated at GB, depending on the GB characters, to fully understand GB atomic structures, which are related to the material’s properties. In this study, various types of GBs were systematically fabricated for doped and pristine ZrO2, ZnO, CeO2 by the bicrystal techniques, and the structures were characterized with an atomic scale by aberration-corrected STEM, EELS and EDS. Based on the experimental results, the role of segregated dopants and vacancies to change the GB structures were investigated by first principles calculation.

Plenary lectures - YUCOMAT 2016

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