AVS 52nd International Symposium
    Surface Science Monday Sessions
       Session SS-MoP

Paper SS-MoP17
Adsorption of Acetic Acid on Zn@sub x@Ni@sub 1-x@ O

Monday, October 31, 2005, 5:00 pm, Room Exhibit Hall C&D

Session: Surface Science Poster Session
Presenter: H.G. García Flores, University of Nebraska-Lincoln and Los Alamos National Laboratory
Authors: H.G. García Flores, University of Nebraska-Lincoln and Los Alamos National Laboratory
A. Starace, University of Nebraska-Lincoln
M.A. Langell, University of Nebraska-Lincoln
Correspondent: Click to Email
Zinc can be dissolved in rocksalt NiO to produce solid solutions of Zn@sub x@Ni@sub 1-x@ O over an approximate composition range of 0 @<=@ x @<=@ 0.35. Both metals are formally M @super 2+@, typically the stable oxidation state in oxides, but the octahedral coordination site of the cations in the rocksalt structure is unusual for zinc, which is typically tetrahedral as is found in wurtzite ZnO. The unique chemical environment of the zinc-nickel oxide solid solution can potentially result in new and interesting surface reactivity. Solid solutions of the zinc-nickel oxide over the range of 0.05 @<=@ Zn @<=@ 0.35 were prepared by calcination at 1200 K and were characterized using powder X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and Auger electron spectroscopy (AES). The Auger parameter for zinc in these homogeneous solid solutions increases indicating stronger ionic character. Acetic acid (CH@sub 3@COOH) was then used to examine the surface reactivity of the mixed-metal solid solution in a series of adsorption experiments that were carried out as a function of zinc concentration and surface pretreatment. At 250 K, the primary adsobate observed is bidentate acetate and, once formed, the species is stable on the substrate to approximately 500 K.