Optically probing Al-O and O-H vibrations to characterize water adsorption and surface reconstruction on alpha-alumina: An experimental and theoretical study
- Oxide/water interfaces are ubiquitous in a wide variety of applications and the environment. Despite this ubiquity, and attendant decades of study, gaining molecular level insight into water/oxide interaction has proven challenging. In part, this challenge springs from a lack of tools to concurrently characterize changes in surface structure (i.e., water/oxide interaction from the perspective of the solid) and O-H population and local environment (i.e., water/oxide interaction from the water perspective). Here, we demonstrate the application of surface specific vibrational spectroscopy to the characterization of the interaction of the paradigmatic alpha-Al2O3(0001) surface and water. By probing both the interfacial Al-O (surface phonon) and O-H spectral response, we characterize this interaction from both perspectives. Through electronic structure calculation, we assign the interfacial Al-O response and rationalize its changes on surface dehydroxylation and reconstruction. Because our technique is all-optical and interface specific,Oxide/water interfaces are ubiquitous in a wide variety of applications and the environment. Despite this ubiquity, and attendant decades of study, gaining molecular level insight into water/oxide interaction has proven challenging. In part, this challenge springs from a lack of tools to concurrently characterize changes in surface structure (i.e., water/oxide interaction from the perspective of the solid) and O-H population and local environment (i.e., water/oxide interaction from the water perspective). Here, we demonstrate the application of surface specific vibrational spectroscopy to the characterization of the interaction of the paradigmatic alpha-Al2O3(0001) surface and water. By probing both the interfacial Al-O (surface phonon) and O-H spectral response, we characterize this interaction from both perspectives. Through electronic structure calculation, we assign the interfacial Al-O response and rationalize its changes on surface dehydroxylation and reconstruction. Because our technique is all-optical and interface specific, it is equally applicable to oxide surfaces in vacuum, ambient atmospheres and at the solid/liquid interface. Application of this approach to additional alumina surfaces and other oxides thus seems likely to significantly expand our understanding of how water meets oxide surfaces and thus the wide variety of phenomena this interaction controls. (C) 2015 AIP Publishing LLC.…
Author details: | Yujin Tong, Jonas WirthGND, Harald KirschGND, Martin Wolf, Peter SaalfrankORCiDGND, Richard Kramer CampenORCiD |
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DOI: | https://doi.org/10.1063/1.4906346 |
ISSN: | 0021-9606 |
ISSN: | 1089-7690 |
Pubmed ID: | https://pubmed.ncbi.nlm.nih.gov/25662657 |
Title of parent work (English): | The journal of chemical physics : bridges a gap between journals of physics and journals of chemistr |
Publisher: | American Institute of Physics |
Place of publishing: | Melville |
Publication type: | Article |
Language: | English |
Year of first publication: | 2015 |
Publication year: | 2015 |
Release date: | 2017/03/27 |
Volume: | 142 |
Issue: | 5 |
Number of pages: | 12 |
Funding institution: | Deutsche Forschungsgemeinschaft through Collaborative Research Center 1109: Understanding of Metal Oxide/Water Systems at the Molecular Scale: Structural Evolution, Interfaces and Dissolution |
Organizational units: | Mathematisch-Naturwissenschaftliche Fakultät / Institut für Chemie |
Peer review: | Referiert |