Electronic properties of the Sm–Pd(111) and Sm–graphene–Pd(111) interfaces
Year: 2025
Type: article
Abstract: The Sm–Pd(111) and Sm-graphene-Pd(111) interfaces have been investigated by X-ray photoelectron spectroscopy (XPS), Ultraviolet photoelectron spectroscopy (UPS), and Low energy electron diffraction (LEED). For Sm–Pd(111) a mixed interface was observed as Sm was deposited on the Pd substrate at ambient temperature. Monolayer (ML) graphene was grown on Pd(111) by exposure to ethylene at elevated temperatures. Subsequently, near monolayer coverage of Sm was deposited at room temperature. Only trivalent Sm atoms were observed in the Sm/Pd(111) system. Divalent Sm atoms were observed in the Sm/graphene/Pd(111) system for sub-monolayer Sm coverage; however, the Sm atoms became trivalent upon annealing above 450 K. Sm atoms migrate to the C-Pd interface predominantly through boundaries between graphene domains of different planar orientations to form a mixed Sm–Pd interface. A monotonic decrease in the sample work function of about 2 eV was observed with increasing Sm coverage for the Sm coverages under investigation.
Source: Applied Surface Science
Authors: Steinar Raaen, Xiaofeng Yu
Institution: Norwegian University of Science and Technology
Language: English
Subfield: Condensed Matter Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $3,930
OpenAlex ID: W4417050319