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Published on: November 9, 2015
Critical adsorption at silicon surfaces in binary liquid mixtures
1Condensed Matter Laboratory, Department of Physics, Kansas State University, Manhattan, Kansas 66506-2601, USA.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|December 31, 2005
Summary
Preferential adsorption in critical liquid mixtures follows a universal function at oxide surfaces but not always at alkylsilane surfaces. This suggests chemical heterogeneities can impact solid-liquid adsorption behavior.
Area of Science:
- Physical Chemistry
- Surface Science
- Thermodynamics
Background:
- Critical binary liquid mixtures exhibit preferential adsorption at interfaces.
- This phenomenon is theoretically expected to follow a universal surface scaling function.
Purpose of the Study:
- To investigate the applicability of a universal surface scaling function to solid-liquid adsorption in critical mixtures.
- To compare adsorption behavior at different solid-liquid interfaces.
Main Methods:
- Studied adsorption of aniline from aniline + cyclohexane critical mixture on an oxide-coated Si wafer.
- Investigated adsorption of n-dodecane from tetrabromoethane + n-dodecane critical mixture on an alkylsilane-coated Si wafer.
Main Results:
- Aniline adsorption on the oxide surface followed the universal scaling function.
- n-Dodecane adsorption on the alkylsilane surface did not conform to previously established adsorption functions.
Conclusions:
- The universal surface scaling function is applicable to certain solid-liquid interfaces in critical mixtures.
- Chemical heterogeneities on alkylsilane surfaces may explain deviations from universal adsorption behavior.
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