Abstract
In this work, multifunctional superamphiphobic fabrics with special wettability were constructed by a facile dip-coating or electrospraying process using easily available materials, viz. silica nanoparticles, heptadecafluorononanoic, and fluoroalkyl silane. The obtained HFA-FAS-SiO2 NPs@surface exhibited a contact angle (CA) of 166.4 +/- 3.7A degrees and 155.9 +/- 2.1A degrees to water and hexadecane, respectively. In addition, this surface also showed stable repellency toward various corrosive droplets at a wide range of pH values, including HCl (pH = 1), NaCl (pH = 7), and NaOH (pH = 14) solutions. After immersion in the strong acid and base solutions for 24 h, the cotton surface still maintained excellent anti-wetting property. The surface was durable enough to withstand 120 cycles of abrasion and 5 cycles of accelerated standard laundry and still kept a water CA higher than 140A degrees and an oil CA higher than 120A degrees. Another treatment method adopted in this work, electrospraying has been proved to be able to realize asymmetric wetting with one side displaying highly anti-wetting behavior and the other side retaining the inherent hydrophilic and oleophilic nature of the pristine cotton fabric. Based on this special wettability, the obtained fabric could display a one-way directional transport feature. This method can also be extended to create hydrophilically and oleophilically patterned superamphiphobic cotton fabrics using a template. This novel fabric is useful for the development of intelligent cellulose-based substrates for various applications.