Site Competition During Coadsorption of Acetone with Methanol and Water on TiO2(110)

Journal Article · Tue Aug 02 04:00:00 EDT 2011 · Langmuir, 27(15):9430-9438

DOI:https://doi.org/10.1021/la2016726· OSTI ID:1025082

Shen, Mingmin; Henderson, Michael A

The competitive interaction between acetone and two solvent molecules (methanol and water) for surface sites on rutile TiO2(110) was studied using temperature programmed desorption (TPD). On a vacuum reduced TiO2(110) surface, which possessed ~5% oxygen vacancy sites, excess methanol displaced preadsorbed acetone molecules to weakly bound and physisorbed desorption states below 200 K, whereas acetone was stabilized to 250 K against displacement by methanol on an oxidized surface through formation of an acetone-diolate species. These behaviors of acetone differ from the competitive interactions between acetone and water in that acetone is less susceptible to displacement by water. Examination of acetone+methanol and acetone+water multilayer combinations shows that acetone is more compatible in water-ice films than in methanol-ice films, presumably because water has greater potential as a hydrogen-bond donor than does methanol. Acetone molecules displaced from the TiO2(110) surface by water are more likely to be retained in the near-surface region, having a greater opportunity to revisit the surface, than when methanol is used as a coadsorbate. This work was supported by the US Department of Energy Basic Energy Sciences' Chemical Sciences, Geosciences & Biosciences Division. Pacific Northwest National Laboratory is operated by Battelle for the US Department of Energy.

• Research Organization: Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 1025082
• Report Number(s): PNNL-SA-79870; 35219; KC0302010
• Journal Information: Langmuir, 27(15):9430-9438, Journal Name: Langmuir, 27(15):9430-9438 Journal Issue: 15 Vol. 27; ISSN LANGD5; ISSN 0743-7463
• Country of Publication: United States
• Language: English

Related Subjects

10 SYNTHETIC FUELS
ACETONE
DESORPTION
Environmental Molecular Sciences Laboratory
METHANOL
OXYGEN
RUTILE
SOLVENTS
TiO2
WATER
acetone
methanol
photocatalysis
water