Metal overlayers on organic functional groups of self-assembled monolayers: VIII. X-ray photoelectron spectroscopy of the Ni/COOH interface

Journal Article · Mon Nov 01 04:00:00 EST 1999 · Journal of Vacuum Science and Technology, A

DOI:https://doi.org/10.1116/1.582075· OSTI ID:698838

Herdt, G C; Czanderna, A W ^[1]

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1. National Renewable Energy Laboratory, Golden, Colorado 80401 (United States)

The interaction of vacuum deposited Ni with the COOH organic functional groups of mercaptoundecanoic acid [HS(CH{sub 2}){sub 10}COOH] self-assembled monolayers formed on an Au substrate has been characterized with {ital in situ} x-ray photoelectron spectroscopy. Steady loss and complete disappearance of the hydroxyl component of O&hthinsp;1s peak at 532.8 eV provides evidence for the formation of a Ni{endash}O bond at the Ni/COOH interface. Further evidence for interfacial compound formation is provided by a binding energy shift in the high binding energy component of the Ni&hthinsp;2p{sub 3/2} peak from 854.8 to 854.4 eV for Ni coverages below {approximately}0.2 nm. These results are consistent with the donation of electrons from the deposited Ni to the COOH oxygens at low Ni coverages. The absence of the characteristic satellite feature in the Ni&hthinsp;2p peak excludes the possibility that a full electron charge is donated to each COOH organic functional group as a bidentate complex. However, the data are consistent with a two step reaction mechanism in which Ni initially reacts weakly with the oxygens in COOH below one monolayer coverage and then forms a complex above this coverage. {copyright} {ital 1999 American Vacuum Society.}

• OSTI ID: 698838
• Journal Information: Journal of Vacuum Science and Technology, A, Journal Name: Journal of Vacuum Science and Technology, A Journal Issue: 6 Vol. 17; ISSN 0734-2101; ISSN JVTAD6
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
40 CHEMISTRY
BINDING ENERGY
ELECTRON SPECTROSCOPY
INTERFACES
LAYERS
NICKEL
ORGANIC COMPOUNDS
PHOTOELECTRON SPECTROSCOPY
STRUCTURAL CHEMICAL ANALYSIS