Work

Coadsorption properties of CO2 and H2O on TiO2 rutile (110): A dispersion-corrected DFT study

Year: 2012

Type: article

Abstract: Adsorption and reactions of CO(2) in the presence of H(2)O and OH species on the TiO(2) rutile (110)-(1×1) surface were investigated using dispersion-corrected density functional theory and scanning tunneling microscopy. The coadsorbed H(2)O (OH) species slightly increase the CO(2) adsorption energies, primarily through formation of hydrogen bonds, and create new binding configurations that are not present on the anhydrous surface. Proton transfer reactions to CO(2) with formation of bicarbonate and carbonic acid species were investigated and found to have barriers in the range 6.1-12.8 kcal/mol, with reactions involving participation of two or more water molecules or OH groups having lower barriers than reactions involving a single adsorbed water molecule or OH group. The reactions to form the most stable adsorbed formate and bicarbonate species are exothermic relative to the unreacted adsorbed CO(2) and H(2)O (OH) species, with formation of the bicarbonate species being favored. These results are consistent with single crystal measurements which have identified formation of bicarbonate-type species following coadsorption of CO(2) and water on rutile (110).

Source: The Journal of Chemical Physics

DOI: 10.1063/1.4739088

Authors: Dan C. Sorescu, Junseok Lee, Wissam A. Al-Saidi, Kenneth D. Jordan

Institutions: United States Department of Energy, National Energy Technology Laboratory, University of Pittsburgh

Language: English

Topic: TiO2 Photocatalysis and Solar Cells

Subfield: Renewable Energy, Sustainability and the Environment

Field: Energy

Domain: Physical Sciences

Open Access status: bronze

Funders: U.S. Department of Energy, Office of Research and Development, University of Pittsburgh, National Energy Technology Laboratory

Awards: G1386838626, G868695232, G8976590660