Abstract
An ultrathin two-dimensional CeO2 (ceria) phase on a Cu(110) surface has been fabricated and fully characterized by high-resolution scanning tunneling microscopy, photoelectron spectroscopy, and density functional theory. The atomic lattice structure of the ceria/Cu(110) system is revealed as a hexagonal CeO2(111)-type monolayer separated from the Cu(110) surface by a partly disordered Cu–O intercalated buffer layer. The epitaxial coupling of the two-dimensional ceria overlayer to the Cu(110)-O surface leads to a nanoscopic stripe pattern, which creates defect regions of quasi-periodic lattice distortions. The symmetry and lattice mismatch at the interface is clarified to be responsible for the topographic stripe geometry and the related anisotropic strain defect regions at the ceria surface. This ceria monolayer is in a fully oxidized and thermodynamically stable state.
Highlights
Chemistry on oxide surfaces is to a large extent determined by surface defects, which provide the most reactive centers for interacting atoms and molecules.1 In addition to morphological defects such as steps, corners, and kinks, oxygen vacancies are key to oxides’ reactive behavior
Concentration, distribution, and energy of creation of oxygen vacancies essentially determine the catalytic activity of oxide surfaces,1−6 and this is true for cerium oxide, whose diverse applications in physics and chemistry are controlled by the creation and annihilation of oxygen vacancy defects
The surface morphology and atomic structure has been probed in a low-temperature (5 K) scanning tunneling microscopy (STM) system, the oxide stoichiometry has been established by X-ray photoelectron spectroscopy (XPS), and density functional theory (DFT) in its DFT+U form has been applied to model the ceria/Cu[110] surface structure
Summary
Chemistry on oxide surfaces is to a large extent determined by surface defects, which provide the most reactive centers for interacting atoms and molecules.1 In addition to morphological defects such as steps, corners, and kinks, oxygen vacancies are key to oxides’ reactive behavior.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
