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Title: SO2 Adsorption on CeO2(100) and CeO2(111)

Abstract

The adsorption and reaction of sulfur dioxide, SO2, was studied on oxidized and reduced CeOX(100) and compared to previous results on CeOX(111). SO2 adsorbs on oxidized CeO2(100) as sulfite, SO32-, at 200 K and sulfite is the only adsorbate observed on the surface at any temperature. The sulfite desorbs monotonically from 200 to 700 K. The adsorption and desorption of SO2 does not result in any change in the Ce4+ oxidation state. SO2 also adsorbs as sulfite on reduced CeO1.7(100) at 200 K. There is also a small amount of elemental sulfur, S0, formed. As the sample is heated the sulfite decomposes into sulfide, S2-. Roughly 25 % of the adsorbed S either desorbs or diffuses into the bulk of the reduced ceria. The decomposition, and resulting formation of S2- and O2-, re-oxidize some of the Ce3+ to Ce4+. Unlike what has been observed following the adsorption and reaction of many other molecules, the adsorption and reaction of SO2 is virtually identical on CeOX(100) and CeOX(111).

Authors:
Publication Date:
Research Org.:
Brookhaven National Laboratory (BNL), Upton, NY (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1409602
Report Number(s):
BNL-114654-2017-JA¿¿¿
Journal ID: ISSN 1022-5528
DOE Contract Number:
SC0012704
Resource Type:
Journal Article
Resource Relation:
Journal Name: Topics in Catalysis; Journal Volume: 60; Journal Issue: 6-7
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; cerium oxide; sulfur dioxide; sXPS synchrotron

Citation Formats

Mullins, David R. SO2 Adsorption on CeO2(100) and CeO2(111). United States: N. p., 2016. Web. doi:10.1007/s11244-016-0710-z.
Mullins, David R. SO2 Adsorption on CeO2(100) and CeO2(111). United States. doi:10.1007/s11244-016-0710-z.
Mullins, David R. 2016. "SO2 Adsorption on CeO2(100) and CeO2(111)". United States. doi:10.1007/s11244-016-0710-z.
@article{osti_1409602,
title = {SO2 Adsorption on CeO2(100) and CeO2(111)},
author = {Mullins, David R.},
abstractNote = {The adsorption and reaction of sulfur dioxide, SO2, was studied on oxidized and reduced CeOX(100) and compared to previous results on CeOX(111). SO2 adsorbs on oxidized CeO2(100) as sulfite, SO32-, at 200 K and sulfite is the only adsorbate observed on the surface at any temperature. The sulfite desorbs monotonically from 200 to 700 K. The adsorption and desorption of SO2 does not result in any change in the Ce4+ oxidation state. SO2 also adsorbs as sulfite on reduced CeO1.7(100) at 200 K. There is also a small amount of elemental sulfur, S0, formed. As the sample is heated the sulfite decomposes into sulfide, S2-. Roughly 25 % of the adsorbed S either desorbs or diffuses into the bulk of the reduced ceria. The decomposition, and resulting formation of S2- and O2-, re-oxidize some of the Ce3+ to Ce4+. Unlike what has been observed following the adsorption and reaction of many other molecules, the adsorption and reaction of SO2 is virtually identical on CeOX(100) and CeOX(111).},
doi = {10.1007/s11244-016-0710-z},
journal = {Topics in Catalysis},
number = 6-7,
volume = 60,
place = {United States},
year = 2016,
month = 9
}
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