Fabrication And Wettability Of Superhydrophobic And Superoleophobic Surfaces

If the surface had contact angle of water and oil larger than 150 degree, we called it super amphiphobic. In recent years, nano-materials especially functional nano-materials (such as superhydrophobic and superoleophobic materials) have attracted much attention because of their promising applications in our daily life and industrial applications. Associated with the special wetting properties, "self-cleaning" was a technological innovation of cleaning the city building and beautifying the living environment. This thesis was aiming at designing super-water/oil repellent surface treatment technology. By use of several techniques such as sol-gel method , liquid phase method and electrochemistry method, we had succeeded in fabricating superhydrophobic and superoleophobic surfaces on Al and glass substrates. The results revealed that:1. On Al substrates, the superhydrophobic and superoleophobic surfaces, preoared with liquid phase method, demonstrated a disorderly veins micronanostructure. The products were ZnO andβ-Al-Zn compound. Interestingly, the resulting surface after mantled at 150 degree centigrade, the wettability of this surface was changed. And finally, the water contact angle kept a constant degree with about 149.7°.2. After treated by fluoroalkysilane, the micronanostructured surfaces on Al substrates demonstrated a superoleophobic property. The water contact angle was up to 155.5°. For the oil with surface tension more than 45mN/m, the contact angle was about 150°. Also, some oil droplets could roll-off the superoleophobic surface, and the rolling angle was less than 6°.3. On glass substrates, . the superhydrophobic and superoleophobic surfaces were also fabricated by sol-gel and solution methods. After treated by fluoroalkysilane, the surfaces demostrated superhydrophobic and superoleophobic properties. For water, the static contact angle was up to165.8°, the rolling angle was 2.3°. For oil (such as cetane with surface tension of 27.5mN/m, the static contact angle was about 140°.4. Compared to (heptadecafluoro-1,1,2,2-tetrahydrodecyl)trimethoxysilane(FAS) self-assembled monolayers, after (3-Aminopropyl)–triethoxysilane(APTS)-FAS, The hysteresis of contact angle had a marked improvement from 9.8°to 5.6°.5. The rough surfaces were fabricated successfully on the surface of using electrochemistry methods. However, the surfaces could not demonstrate the superhydrophobic and superoleophobic propertis. For water and oil, the static contact angle was only about 90°.