Fabrication of extreme wettability patterns with water-film protection for organic liquids

ABSTRACT

Selective fabrication of superhydrophilic (S-philic) region on a superhydrophobic (S-phobic) surface requires complex technology and high cost, which has limited applications of extreme wettability patterns. In this paper, a twice-chemical-etching approach without special modification is used to prepare the extreme wettability patterns. Superhydrophobicity and superhydrophilicity can be successfully achieved after twice chemical etching for 20 seconds. The obtained patterns can maintain their extreme wettability for at least 30 days. Functional platforms with single-S-philic and multi-S-philic regions are fabricated to manipulate water and various organic liquids with water-film protection in an air environment.

GRAPHICAL ABSTRACT

KEYWORDS:

• Chemical etching
• extreme wettability patterns
• organic liquids
• water-film protection

Acknowledgments

This work was financially supported by the National Basic Research Program of China (Grant No. 2015CB057304), National Natural Science Foundation of China (Grant No. 51305060 and 51275072) and the Fundamental Research Funds for the Central Universities (Grant No. DUT15RC(4)21).