Water adsorption on α-Fe2O3 (0001) at near ambient conditions
Artikel i vetenskaplig tidskrift, 2010
We have investigated hydroxylation and water adsorption on α Fe 2O3(0001) at water vapor pressures up to 2 Torr and temperatures ranging from 277 to 647 K (relative humidity (RH) < 34%) using ambient-pressure X-ray photoelectron spectroscopy (XPS). Hydroxylation occurs at the very low RH of 1 × 10-7 % and precedes the adsorption of molecular water. With increasing RH, the OH coverage increases up to one monolayer (ML) without any distinct threshold pressure. Depth profiling measurements showed that hydroxylation occurs only at the topmost surface under our experimental conditions. The onset of molecular water adsorption varies from ∼2 ×10-5 to ∼4 ?10-2 % RH depending on sample temperature and water vapor pressure. The coverage of water reaches 1 ML at ∼15% RH and increases to 1.5 ML at 34% RH.
Water adsorption
Threshold pressures
Relative humidities
Sample temperature
Experimental conditions
Molecular water
Författare
S. Yamamoto
Stanford Synchrotron Radiation Laboratory
FOM Institute for Atomic and Molecular Physics - AMOLF
T. Kendelewicz
Stanford University
J. T. Newberg
Lawrence Berkeley National Laboratory
Guido Ketteler
Chalmers, Teknisk fysik, Kemisk fysik
D. E. Starr
Brookhaven National Laboratory
Lawrence Berkeley National Laboratory
E. R. Mysak
Lawrence Berkeley National Laboratory
K. J. Andersson
Stanford Synchrotron Radiation Laboratory
Danmarks Tekniske Universitet
Stockholms universitet
H. Ogasawara
Stanford Synchrotron Radiation Laboratory
H. Bluhm
Lawrence Berkeley National Laboratory
M. Salmeron
CALIFORNIA UNIVERSITY OF
Lawrence Berkeley National Laboratory
G. E. Brown Jr
Stanford University
Stanford Synchrotron Radiation Laboratory
A. Nilsson
Stanford Linear Accelerator Center
Stockholms universitet
Stanford Synchrotron Radiation Laboratory
Journal of Physical Chemistry C
1932-7447 (ISSN) 1932-7455 (eISSN)
Vol. 114 5 2256-2266Ämneskategorier (SSIF 2011)
Fysik
DOI
10.1021/jp909876t