Nanoscale analysis of the oxidation state and surface termination of praseodymium oxide ultrathin films on ruthenium(0001).

Author(s) Flege, J.I.; Krisponeit, J.O.; Höcker, J.; Hoppe, M.; Niu, Y.; Zakharov, A.; Schaefer, A.; Falta, J.; Krasovskii, E.E.
Journal Ultramicroscopy
Date Published 2017 Dec

The complex structure and morphology of ultrathin praseodymia films deposited on a ruthenium(0001) single crystal substrate by reactive molecular beam epitaxy is analyzed by intensity-voltage low-energy electron microscopy in combination with theoretical calculations within an ab initio scattering theory. A rich coexistence of various nanoscale crystalline surface structures is identified for the as-grown samples, notably comprising two distinct oxygen-terminated hexagonal Pr2O3(0001) surface phases as well as a cubic Pr2O3(111) and a fluorite PrO2(111) surface component. Furthermore, scattering theory reveals a striking similarity between the electron reflectivity spectra of praseodymia and ceria due to very efficient screening of the nuclear charge by the extra 4f electron in the former case.

DOI 10.1016/j.ultramic.2017.05.007
ISSN 1879-2723
Citation Ultramicroscopy. 2017;183:6166.

Related Applications, Forms & Industries