A ferromagnetic Eu-Pt surface compound grown below hexagonal boron nitride
Journal article, 2023
One of the fundamental applications for monolayer-thick 2D materials is their use as protective layers of metal surfaces and in situ intercalated reactive materials in ambient conditions. Here we investigate the structural, electronic, and magnetic properties, as well as the chemical stability in air of a very reactive metal, Europium, after intercalation between a hexagonal boron nitride (hBN) layer and a Pt substrate. We demonstrate that Eu intercalation leads to a hBN-covered ferromagnetic EuPt2 surface alloy with divalent Eu2+ atoms at the interface. We expose the system to ambient conditions and find a partial conservation of the di-valent signal and hence the Eu-Pt interface. The use of a curved Pt substrate allows us to explore the changes in the Eu valence state and the ambient pressure protection at different substrate planes. The interfacial EuPt2 surface alloy formation remains the same, but the resistance of the protecting hBN layer to ambient conditions is reduced, likely due to a rougher surface and a more discontinuous hBN coating.
Author
Alaa Mohammed Idris Bakhit
Spanish National Research Council (CSIC)
University of the Basque Country (UPV/EHU)
Khadiza Ali
Donostia International Physics Center
Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics
Anna A. Makarova
Freie Universität Berlin
Igor Píš
National Research Council of Italy (CNR)
Federica Bondino
National Research Council of Italy (CNR)
Roberto Sant
European Synchrotron Radiation Facility (ESRF)
Saroj Prasad Dash
Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics
R. Castrillo-Bodero
Spanish National Research Council (CSIC)
Yuri Hasegawa
College of Life Sciences
Spanish National Research Council (CSIC)
J. E. Ortega
Donostia International Physics Center
Spanish National Research Council (CSIC)
University of the Basque Country (UPV/EHU)
L. Fernandez
Spanish National Research Council (CSIC)
F. Schiller
Spanish National Research Council (CSIC)
Donostia International Physics Center
Nanoscale
2040-3364 (ISSN) 20403372 (eISSN)
Vol. 15 27 11517-11528Subject Categories (SSIF 2011)
Condensed Matter Physics
DOI
10.1039/d3nr00630a