Bioinspired multifunctional polymer-nanoparticle-surfactant complex nanocomposite surfaces for antibacterial oil-water separation

Bioinspired polymer-nanoparticle-fluorosurfactant complex composite coatings are shown to display fast-switching oleophobic-hydrophilic properties. The large switching parameters (difference between the equilibrium oil and water static contact angles) are attributed to nanoparticle enhanced surface roughening (leading to improvement in hydrophilicity and oleophobicity for optimum nanoparticle loadings). Nanoparticle incorporation also increases hardness of the coatings (durability). Porous substrates coated with these polymer-nanoparticle-fluorosurfactant complex composite coatings are found to readily separate oil-water mixtures under both static and continuous flow as well as displaying antibacterial surface properties against Escherichia coli (Gram-negative bacteria) and Staphylococcus aureus (Gram-positive bacteria). A key advantage of this approach for coating substrates is its single-step simplicity. Potential applications include provision of safe drinking water, environmental pollution clean-up, and anti-fogging.