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Abstract This work characterizes the structural, magnetic, and ferroelectric properties of epitaxial LuFeO3orthoferrite thin films with different Lu/Fe ratios. LuFeO3thin films are grown by pulsed laser deposition on SrTiO3substrates with Lu/Fe ratio ranging from 0.6 to 1.5. LuFeO3is antiferromagnetic with a weak canted moment perpendicular to the film plane. Piezoresponse force microscopy imaging and switching spectroscopy reveal room temperature ferroelectricity in Lu‐rich and Fe‐rich films, whereas the stoichiometric film shows little polarization. Ferroelectricity in Lu‐rich films is present for a range of deposition conditions and crystallographic orientations. Positive‐up‐negative‐down ferroelectric measurements on a Lu‐rich film yield ≈13 µC cm−2of switchable polarization, although the film also shows electrical leakage. The ferroelectric response is attributed to antisite defects analogous to that of Y‐rich YFeO3, yielding multiferroicity via defect engineering in a rare earth orthoferrite.
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The effects of near-surface atomic order on the catalytic properties of Cu 3 Au and CuAu 3 intermetallics for the CO 2 reduction reaction
Density functional theory (DFT) calculations combined with cluster expansions (CE) were employed to explore the catalytic activity of stoichiometric and non-stoichiometric Cu3Au and CuAu3surfaces for CO2reduction to CO.
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- Award ID(s):
- 1930013
- PAR ID:
- 10537327
- Publisher / Repository:
- Royal Society of Chemistry
- Date Published:
- Journal Name:
- Catalysis Science & Technology
- Volume:
- 13
- Issue:
- 22
- ISSN:
- 2044-4753
- Page Range / eLocation ID:
- 6415 to 6430
- Subject(s) / Keyword(s):
- CO2 reduction catalysis density functional theory alloy catalysts intermetallics
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/D3CY00658A
