title: The interfacial structure of water/protonated α-Al2O3 (11 ̅20) as a function of pH.
abstract: Sum frequency vibrational spectroscopy (SFVS) was used to study the structure of the protonated α-Al(2)O(3) (11 ̅20), and water/α-Al(2)O(3) (11 ̅20) interfaces as a function of pH. By combining SFVS spectra with an oxygen-terminated model suggested by x-ray reflectivity, we are able to understand several details of the protonated α-Al(2)O(3) (11 ̅20) interface structure. For example, the spectral changes observed for the water/α-Al(2)O(3) (11 ̅20) interface with varying pH could be accounted for by the protonation/deprotonation of particular surface hydroxyls. Our spectra also indicate that the point of zero charge for this interface is at pH ~ 6.7.
authors.affiliation: Department of Physics, University of California, Berkeley, CA 94720, USA.
authors.forename: J
authors.initials: J
authors.lastname: Sung
authors.forename: Y R
authors.initials: YR
authors.lastname: Shen
authors.forename: G A
authors.initials: GA
authors.lastname: Waychunas