Abstract
We use the bending of silicon microcantilevers to measure changes in mechanical stress at interfaces between phenol - water mixtures and SiO 2. The curvature of the microcantilever is measured by an optical system that combines a rapidly scanning laser beam, a position-sensitive detector, and lock-in detection to achieve a long-time stability on the order of 6 mN m -1 over 4 h and a short-time sensitivity of better than 1 mN m -1. Thermally oxidized Si shows the smallest changes in interface stress as a function of phenol concentration in water. For hydrophilic SiO 2 prepared by chemical treatment, the change in interface stress at 5 wt % phenol in water is larger than that of thermally oxidized Si by -60 mN m -1 for SiO 2 formed by exposure of the silicon microcantilever to ozone, the change in surface stress is larger than that of thermally oxidized Si by -330 mN m -1.
Original language | English (US) |
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Pages (from-to) | 9062-9066 |
Number of pages | 5 |
Journal | Langmuir |
Volume | 22 |
Issue number | 21 |
DOIs | |
State | Published - Oct 10 2006 |
ASJC Scopus subject areas
- General Materials Science
- Condensed Matter Physics
- Surfaces and Interfaces
- Spectroscopy
- Electrochemistry