Walz, Marie-Madeleine and Werner, Josephina and Ekholm, Victor and Prisle, Nønne and Öhrwall, Gunnar and Björneholm, Olle
(2016).
Alcohols at the aqueous surface: chain length and isomer effects.
Physical Chemistry Chemical Physics. 18
:9
, 6648-6656
[Journal article]
![]() |
PDF
5MB |
Official URL: http://dx.doi.org10.1039/C5CP06463E
Abstract
Surface-active organic molecules at the liquid-vapor interface are of great importance in atmospheric science. Therefore, we studied the surface behavior of alcohol isomers with different chain lengths (C4-C6) in aqueous solution with surface-and chemically sensitive X-ray photoelectron spectroscopy (XPS), which reveals information about the surface structure on a molecular level. Gibbs free energies of adsorption and surface concentrations are determined from the XPS results using a standard Langmuir adsorption isotherm model. The free energies of adsorption, ranging from around -15 to -19 kJ mol(-1) (C4-C6), scale linearly with the number of carbon atoms within the alcohols with Delta G(Ads) per-CH2-approximate to -2 kJ mol(-1.) While for the linear alcohols, surface concentrations lie around 2.4 x 10(14) molecules per cm(2) at the bulk concentrations where monolayers are formed, the studied branched alcohols show lower surface concentrations of around 1.6 x 10(14) molecules per cm(2), both of which are in line with the molecular structure and their orientation at the interface. Interestingly, we find that there is a maximum in the surface enrichment factor for linear alcohols at low concentrations, which is not observed for the shorter branched alcohols. This is interpreted in terms of a cooperative effect, which we suggest to be the result of more effective van der Waals interactions between the linear alcohol alkyl chains at the aqueous surface, making it energetically even more favorable to reside at the liquid-vapor interface.
Authors/Creators: | Walz, Marie-Madeleine and Werner, Josephina and Ekholm, Victor and Prisle, Nønne and Öhrwall, Gunnar and Björneholm, Olle | ||||||
---|---|---|---|---|---|---|---|
Title: | Alcohols at the aqueous surface: chain length and isomer effects | ||||||
Series Name/Journal: | Physical Chemistry Chemical Physics | ||||||
Year of publishing : | 2016 | ||||||
Volume: | 18 | ||||||
Number: | 9 | ||||||
Page range: | 6648-6656 | ||||||
Number of Pages: | 9 | ||||||
Publisher: | Royal Society of Chemistry | ||||||
ISSN: | 1463-9084 | ||||||
Language: | English | ||||||
Publication Type: | Journal article | ||||||
Refereed: | Yes | ||||||
Article category: | Scientific peer reviewed | ||||||
Version: | Accepted version | ||||||
Full Text Status: | Public | ||||||
Agris subject categories.: | X Agricola extesions > X50 Chemistry | ||||||
Subjects: | (A) Swedish standard research categories 2011 > 1 Natural sciences > 103 Physical Sciences > Atom and Molecular Physics and Optics (A) Swedish standard research categories 2011 > 1 Natural sciences > 104 Chemical Sciences > Organic Chemistry (A) Swedish standard research categories 2011 > 1 Natural sciences > 104 Chemical Sciences > Physical Chemistry (A) Swedish standard research categories 2011 > 1 Natural sciences > 104 Chemical Sciences > Inorganic Chemistry (A) Swedish standard research categories 2011 > 1 Natural sciences > 105 Earth and Related Environmental Sciences > Meteorology and Atmospheric Sciences | ||||||
Agrovoc terms: | alcohols, surfactants, atmospheric chemistry | ||||||
Keywords: | alcohols, surfactants, atmospheric chemistry | ||||||
URN:NBN: | urn:nbn:se:slu:epsilon-e-3727 | ||||||
Permanent URL: | http://urn.kb.se/resolve?urn=urn:nbn:se:slu:epsilon-e-3727 | ||||||
Additional ID: |
| ||||||
ID Code: | 13544 | ||||||
Faculty: | NJ - Fakulteten för naturresurser och jordbruksvetenskap | ||||||
Department: | (NL, NJ) > Department of Chemistry and Biotechnology (140101-161231) | ||||||
Deposited By: | SLUpub Connector | ||||||
Deposited On: | 10 Oct 2016 08:01 | ||||||
Metadata Last Modified: | 09 Sep 2020 14:17 |
Repository Staff Only: item control page