Chemically Stable and Mechanically Durable Superamphiphobic Aluminum Surface with a Micro/Nanoscale Binary Structure

We
developed a simple fabrication method to prepare a superamphiphobic
aluminum surface. On the basis of a low-energy surface and the combination
of micro- and nanoscale roughness, the resultant surface became super-repellent
toward a wide range of liquids with surface tensions of 25.3–72.1
mN m–1. The applied approach involved (1) the formation
of an irregular microplateau structure on an aluminum surface, (2)
the fabrication of a nanoplatelet structure, and (3) fluorination
treatment. The chemical stability and mechanical durability of the
superamphiphobic surface were evaluated in detail. The results demonstrated
that the surface presented an excellent chemical stability toward
cool corrosive liquids (HCl/NaOH solutions, 25 °C) and 98% concentrated
sulfuric acid, hot liquids (water, HCl/NaOH solutions, 30–100
°C), solvent immersion, high temperature, and a long-term period.
More importantly, the surface also exhibited robust mechanical durability
and could withstand multiple-fold, finger-touch, intensive scratching
by a sharp blade, ultrasonication treatment, boiling treatment in
water and coffee, repeated peeling by adhesive tape, and even multiple
abrasion tests under 500 g of force without losing superamphiphobicity.
The as-prepared superamphiphobic surface was also demonstrated to
have excellent corrosion resistance. This work provides a simple,
cost-effective, and highly efficient method to fabricate a chemically
stable and mechanically robust superamphiphobic aluminum surface,
which can find important outdoor applications.