Abstract
We continue our investigation of the behavior of simple ions at aqueous interfaces, employing the combination of two surface-sensitive nonlinear spectroscopy tools, broadband deep UV electronic sum-frequency generation and UV second harmonic generation, to characterize the adsorption of thiocyanate to the interface of water with toluene─a prototypical hydrophobe. We find that both the interfacial spectrum and the Gibbs free energy of adsorption closely match results previously reported for the air-water interface. We observe no relative spectral shift in the higher-energy CTTS transition of thiocyanate, implying similar solvation environments for the two interfaces. Similarly, the Gibbs free energies of adsorption agree within error; however, we expect the respective enthalpic and entropic contributions to differ between the two interfaces, similar to our earlier findings for the air-water versus graphene-water interfaces. Further experiments and theoretical modeling are necessary to quantify the mechanistic differences.
Original language | English (US) |
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Pages (from-to) | 222-228 |
Number of pages | 7 |
Journal | Journal of Physical Chemistry Letters |
Volume | 13 |
Issue number | 1 |
DOIs | |
State | Published - Dec 30 2021 |
Externally published | Yes |
Bibliographical note
KAUST Repository Item: Exported on 2022-05-25Acknowledged KAUST grant number(s): OSR-2019-CPF-4109.3
Acknowledgements: This work was supported by the Department of Energy, Office of Basic Energy Sciences, through the Chemical Sciences Division at the Lawrence Berkeley National Laboratory under contract #CH403503, through King Abdullah University of Science and Technology (KAUST) under contract #OSR-2019-CPF-4109.3, and through the ACS Petroleum Research Fund under grant #59408-ND6
This publication acknowledges KAUST support, but has no KAUST affiliated authors.
ASJC Scopus subject areas
- General Materials Science