Stacking behavior of twin-free type-B oriented CeO2(111) films on hexagonal Pr2O3(0001)/Si(111) systems

Article

关键词: PRASEODYMIUM SESQUIOXIDE FILMS;    OXYGEN STORAGE CAPACITY;    EPITAXIAL-GROWTH;    REDOX PROPERTIES;    OXIDES;    SI(111);    HETEROSTRUCTURES;    CE;    ETHYLENE;    DIOXIDE;   

DOI  :  10.1103/PhysRevB.85.035302

来源: SCIE

【 摘 要 】

Tailored CeO2/Pr2O3 thin-film oxide heterostructures are of interest for model catalysis studies by surface science techniques. For this purpose, thin CeO2(111) films were grown by molecular beam epitaxy on hex-Pr2O3(0001)/Si(111) as well as on cub-Pr2O3(111)/Si(111) support systems. A comparative, rigorous structure investigation by reflection high-energy electron diffraction transmission electron microscopy and laboratory and synchrotron based x-ray diffraction is reported. It is found that twin-free, exclusively type-B oriented CeO2(111) films are obtained on both oxide supports. CeO2(111) films adopt the stacking sequence from the cub-Pr2O3(111) buffer, but the transfer of the stacking information is less evident in the case of hex-Pr2O3(0001) films. Ab initio calculations are applied to understand the unusual stacking behavior of the CeO2(111) on the hex-Pr2O3(0001)/Si(111) system. It is revealed that the type-B stacking configuration is the more favorable configuration by 8 eV/nm(2) due to electronic and crystallographic factors.

【 授权许可】

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