Transcript Durability of hydrophobic coatings for superhydrophobic aluminum

Applied Surface Science 282 (2013) 73– 76
Durability of hydrophobic coatings for
superhydrophobic aluminum oxide
Elliot Jennera a, Charlotte Barbierb b, Brian D’Ursoa a,∗
a
Department of Physics & Astronomy, University of Pittsburgh, Pittsburgh, PA 15260, United States
b Oak Ridge National Laboratory, Oak Ridge, TN 37831, United States
Paper Survey
Advisor : Cheng-Hsin Chuang
Advisee ﹕Wen-Yu Lee
Institute of Mechanical Engineering
Date ﹕2013/10/24
Material and methods – Fabrication
 Anodization parameters:
Anodization: 320 V, 0.051 A/m2 at 18-20 ̊C, 0.1175 M Citric acid
Pore widening etching: 2 wt% Tetramethylammonium hydroxide (TMAH) at 18 ̊C
 Hydrophobic fluoropolymer:
Solvey Plastics Hyflon AD-60
Fig. 1. SEM image of a spiked PAA surface in cross section at
20◦ inclination, thickness 4um. Note the visible steps made by
alternation of 8 anodization and 7 etching steps.
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Material and methods – Experimental method
F0~F5: Baked for 15 min at 150 ̊C
After baked:
• F3: Spin coated at 1000rpm with 2wt% Hyflon in 3M Fluorinert(FC-40)
• F5: Spin coated with PGMEA:HMDS in 4:1 solution at 4000rpm
→ Followed by F3 Hyflon solution
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Results and discussion
161o±1
Fig. 2. Profile image showing contact
angle of a drop of water on the
material before full immersion in
water was undertaken. Drop is held
in place with a needle suspended
above the surface.
Fig. 3. Rolling angle as a function of time. A reading of 90◦ indicates the drop
adhered up to or past vertical tilt.
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Results and discussion
AAO
Sample
Edge
Fig. 4. SEM images of samples, taken at a 20◦ angle after testing and cracked to show profile.
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Thanks for your attention!
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