Robust hydrophobic surface driven by Al2O3/glass composite coatings

Abstract Fabrication of hydrophobic surface with exceptional mechanical robustness has been of considerable interest for its urgent practical application. Herein, we demonstrate a facile approach to fabricate mechanically robust, hydrophobic surface by combining Al 2 O 3 , glass frits, and hydrophobic solution. Al 2 O 3 -based composite coatings with different roughness were prepared by controlling the ratio of Al 2 O 3 particles and glass frits. Surface properties of Al 2 O 3 -based composite coatings were carefully modified by hydrophobic fluorine-containing sol-gel solution. Hydrophobic sol-gel solution-coated Al 2 O 3 -based coatings (H-Al 2 O 3 ) show strong hydrophobicity, and water contact angle of 132.38° was achieved at an optimal Al 2 O 3 /glass frits ratio of 50. To demonstrate the mechanical robustness of our H-Al 2 O 3 , the hydrophobicity was evaluated after performing sandpaper (400 mesh) abrasion and ultrasonication. The H-Al 2 O 3 still retained great water repellency even after sandpaper abrasion for 100 cm and ultrasonication for 60 min, exhibiting excellent mechanical robustness. We believed that the presented method could provide a straightforward and effective route to fabricate mechanically robust and hydrophobic surface on various substrate materials for a great number of potential applications.