Interactions of low energy reactive ions with surfaces. I. Dose and energy dependence of 3--300 eV C/sup +/, O/sup +/, and CO/sup +/ reactions with a Ni(111) surface

Journal Article · Sun May 01 00:00:00 EDT 1988 · J. Chem. Phys.; (United States)

OSTI ID:5372040

Kang, H; Kasi, S R; Rabalais, J W

Reactions of C/sup +/, O/sup +/, and CO/sup +/ ions with a clean Ni(111) surface are studied as a function of both kinetic energy (E/sub k/) and ion dose for a range of chemically important energies (3--300 eV). An energy- and mass-selected, differentially pumped ion beam and ultrahigh vacuum spectrometer system which is designed to perform E/sub k/ dependence measurements of low-E/sub k/ ion--surface interactions is described. The Ni surface is exposed to low-E/sub k/ beams of these ions and concentrations of the resulting adspecies are monitored by Auger electron spectroscopy (AES) and x-ray and UV photoelectron spectroscopy (XPS and UPS). Reactions of C/sup +/ and O/sup +/ with Ni(111) yield nickel carbide (for monolayer doses) and oxide, respectively. These reactions are efficient at low E/sub k/; reaction probabilities P/sub r/ = 0.6--0.8 are observed for E/sub k/ <20 eV. P/sub r/ decreases slowly with increasing E/sub k/ until implantation of ions into the solid becomes significant. In the reaction of CO/sup +/ with Ni(111), the yield of molecular CO on the surface drops rapidly from 0.5 to below 0.1 in the range 3--10 eV. Collisional dissociation of CO/sup +/, which results in formation of surface NiC and NiO adspecies, increases with E/sub k/ and becomes the dominant process above 9 eV. Depth profile studies of the reacted surfaces indicate that implantation of C/sup +/ into subsurface Ni layers is more facile than implantation of O/sup +/ in the high energy portion of the range investigated. A Monte Carlo simulation of the atomic ion penetration into Ni has been carried out and the results are compared with experimental measurements.

• Research Organization: Department of Chemistry, University of Houston, Houston, Texas 77004
• OSTI ID: 5372040
• Journal Information: J. Chem. Phys.; (United States), Vol. 88:9
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
CARBON IONS
COLLISIONS
DESORPTION
CARBON MONOXIDE
NICKEL
ION COLLISIONS
SORPTIVE PROPERTIES
NICKEL CARBIDES
CHEMICAL REACTION YIELD
NICKEL OXIDES
OXYGEN IONS
ATOMIC IONS
AUGER ELECTRON SPECTROSCOPY
DISSOCIATION
EV RANGE 10-100
EV RANGE 100-1000
ION BEAMS
MOLECULAR IONS
PHOTOELECTRON SPECTROSCOPY
BEAMS
CARBIDES
CARBON COMPOUNDS
CARBON OXIDES
CHALCOGENIDES
CHARGED PARTICLES
ELECTRON SPECTROSCOPY
ELEMENTS
ENERGY RANGE
EV RANGE
IONS
METALS
NICKEL COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
SPECTROSCOPY
SURFACE PROPERTIES
TRANSITION ELEMENT COMPOUNDS
TRANSITION ELEMENTS
YIELDS
656003* - Condensed Matter Physics- Interactions between Beams &amp; Condensed Matter- (1987-)
400201 - Chemical &amp; Physicochemical Properties