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Title: Nanoscopic Nickel Aluminate Spinel (NiAl2O4) Formation During NiAl(111) Oxidation

Abstract

Oxidation of a NiAl(111) single crystal surface was investigated using high resolution soft X-ray photoelectron spectroscopy (HRSXPS), high resolution scanning electron microscopy (HRSEM), energy dispersive X-ray spectroscopy (EDS), X-ray mapping, and atomic force microscopy (AFM). After repeated oxygen exposure, annealing, and cleaning cycles under ultrahigh vacuum conditions, a new oxide phase in the form of tiny 3-dimensional surface structures was detected. These features are several micrometers long and {approx}300 nm high and oriented along low index {l_angle}{bar 1}01{r_angle} directions in the plane of the substrate; they have nickel aluminate spinel (NiAl{sub 2}O{sub 4}) stoichiometry. We propose that repeated cycles of oxygen dosing and annealing of the NiAl(111) surface leads to oxygen diffusion into the bulk and nucleation of spinel below the surface.

Authors:
; ;
Publication Date:
Research Org.:
Brookhaven National Laboratory (BNL) National Synchrotron Light Source
Sponsoring Org.:
Doe - Office Of Science
OSTI Identifier:
930293
Report Number(s):
BNL-80997-2008-JA
Journal ID: ISSN 0039-6028; SUSCAS; TRN: US200822%%1246
DOE Contract Number:
DE-AC02-98CH10886
Resource Type:
Journal Article
Resource Relation:
Journal Name: Surface Science; Journal Volume: 601; Journal Issue: 3
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; NICKEL ALLOYS; ALUMINIUM ALLOYS; OXIDATION; NICKEL OXIDES; ALUMINIUM OXIDES; SPINELS; SYNTHESIS; OXYGEN; NUCLEATION; national synchrotron light source

Citation Formats

Loginova,E., Cosandey, F., and Madey, T.. Nanoscopic Nickel Aluminate Spinel (NiAl2O4) Formation During NiAl(111) Oxidation. United States: N. p., 2007. Web. doi:10.1016/j.susc.2006.11.047.
Loginova,E., Cosandey, F., & Madey, T.. Nanoscopic Nickel Aluminate Spinel (NiAl2O4) Formation During NiAl(111) Oxidation. United States. doi:10.1016/j.susc.2006.11.047.
Loginova,E., Cosandey, F., and Madey, T.. Mon . "Nanoscopic Nickel Aluminate Spinel (NiAl2O4) Formation During NiAl(111) Oxidation". United States. doi:10.1016/j.susc.2006.11.047.
@article{osti_930293,
title = {Nanoscopic Nickel Aluminate Spinel (NiAl2O4) Formation During NiAl(111) Oxidation},
author = {Loginova,E. and Cosandey, F. and Madey, T.},
abstractNote = {Oxidation of a NiAl(111) single crystal surface was investigated using high resolution soft X-ray photoelectron spectroscopy (HRSXPS), high resolution scanning electron microscopy (HRSEM), energy dispersive X-ray spectroscopy (EDS), X-ray mapping, and atomic force microscopy (AFM). After repeated oxygen exposure, annealing, and cleaning cycles under ultrahigh vacuum conditions, a new oxide phase in the form of tiny 3-dimensional surface structures was detected. These features are several micrometers long and {approx}300 nm high and oriented along low index {l_angle}{bar 1}01{r_angle} directions in the plane of the substrate; they have nickel aluminate spinel (NiAl{sub 2}O{sub 4}) stoichiometry. We propose that repeated cycles of oxygen dosing and annealing of the NiAl(111) surface leads to oxygen diffusion into the bulk and nucleation of spinel below the surface.},
doi = {10.1016/j.susc.2006.11.047},
journal = {Surface Science},
number = 3,
volume = 601,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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