Biomimetic Superhydrophobic Films with an Extremely Low Roll-Off Angle Modified by F16CuPc via Two-Step Fabrication

Abstract

Superhydrophobicity is the phenomenon of which the water contact angle (WCA) of droplets on a solid surface is greater than 150°. In the present paper, we prepare a superhydrophobic film with a structure similar to the surface of a lotus leaf, which is composed of polydimethylsiloxane (PDMS), zinc oxide (ZnO), a molecular sieve (MS) and 1,2,3,4,8,9,10,11,15,16,17,18,22,23,24,25-hexadecafluorophthalocyanine copper(II) (F16CuPc). The F16CuPc was used as the modifier to reduce the surface energy of the biomimetic micro-nanostructure. With the introduction of F16CuPc, the superhydrophobic properties of the surface were enhanced so that the WCA and water roll-off angle could reach 167.1° and 0.5°, respectively. Scanning electron microscopy, X-ray energy spectrometry, and X-ray photoelectron spectroscopy analyses verified that the enhanced superhydrophobic properties of the film were mainly attributed to the modification of F16CuPc. Finally, thermal, mechanical, and chemical stability studies, as well as the influences of UV and underwater immersion on the superhydrophobic film were investigated. This developed two-step fabrication method may be a potential direction for superhydrophobic surface fabrication due to its simple process, excellent superhydrophobic property, and favorable stability.