Copper-based superhydrophobic materials with long-term durability, stability, regenerability, and self-cleaning property

Abstract

This work reports a simple and environment-friendly method for fabricating copper-based superhydrophobic materials by oxidation, lauryl mercaptan modification, and compression moulding. The as-prepared copper blocks are characterized by XRD, FT-IR, SEM, EDS, and contact angle measurements. Results show that the block surfaces show cauliflower-like structure, while long lauryl mercaptan chains are self-assembled onto surfaces successfully. Consequently, the superhydrophobic copper blocks with a contact angle and a sliding angle of 155.2° and below 5° are obtained. Moreover, the strong repellency of these copper-based materials have universality for milk, blue ink, methyl orange solution, methylene blue solution, and so on. The materials as well as the superhydrophobicity remain even in adverse conditions. They could be placed in the air for ten months, soaked in water for half a month, or over a wide pH range (i.e, pH=6–14) without any notable changes. More importantly, the superhydrophobicity can be regenerated once the superhydrophobic surfaces are destroyed by abrasion, scratching, or fouling. Meanwhile, the superhydrophobic copper blocks have excellent self-cleaning property. The contaminating particles on the copper blocks can be easily taken away by rolling water droplets. The results show that these copper-based superhydrophobic materials have long-term durability and stability, and may see practical application of the superhydrophobic materials.