ADSORPTION OF DMSO AT THE FREE-SURFACE OF WATER - SURFACE EXCESSES AND SURFACE-POTENTIAL SHIFTS IN THE LOW CONCENTRATION RANGE

Authors
DABKOWSKI J ZAGORSKA I DABKOWSKA M KOCZOROWSKI Z TRASATTI S
Citation
J. Dabkowski et al., ADSORPTION OF DMSO AT THE FREE-SURFACE OF WATER - SURFACE EXCESSES AND SURFACE-POTENTIAL SHIFTS IN THE LOW CONCENTRATION RANGE, Journal of the Chemical Society. Faraday transactions, 92(20), 1996, pp. 3873-3878
Citations number
50
Categorie Soggetti
Chemistry Physical","Physics, Atomic, Molecular & Chemical
Journal title
Journal of the Chemical Society. Faraday transactions → ACNP
ISSN journal
09565000
Volume
92
Issue
20
Year of publication
1996
Pages
3873 - 3878
Database
ISI
SICI code
0956-5000(1996)92:20<3873:AODATF>2.0.ZU;2-5
Abstract
The adsorption of dimethyl sulfoxide (DMSO) at the free surface of aqu eous solutions has been studied by means of surface tension and surfac e potential measurements in the low concentration range up to 3 mol dm (-3). In this range the surface excess (Gamma) cs. concentration plot shows a definite trend to saturation with Gamma(max)=2.2x10(-10) mol c m(-2). This value, well below that for a close-packed monolayer, is ex plained in terms of adsorption of hydrated DMSO molecules. The shift o f the surface potential indicates that adsorbed DMSO molecules point t heir CH3 groups towards the exterior of the liquid phase. A model is s uggested and worked out to describe the adsorption behaviour.