Achieving Effective Oil/Water Separation with Bicomponent Supramolecular Hydrogel Paint Coated Metal Mesh

The increasing discharge of oily wastewater and frequent oil spill accidents pose a great threat to our environment and cause a great waste of valuable resources. However, most existing methods to separate oily water often involve unique equipment and toxic chemicals that hinder their commercial applications. Inspired by the synergy of various additives in commercial paint, we proposed a strategy to fabricate a metal mesh for oil–water separation by using a bicomponent hydrogel paint. This paint consists of an undercoat and a topcoat. Owing to the exceptional adhesion and molecular recognition effect, the paint can show a high binding degree. In addition, the hydrogel paint can decouple polymerization from crosslinking due to the reversible hydrogen bond crosslinking of topcoat, resulting in a separation of labor between paint makers and paint users. The rough as-prepared metal mesh with hydrophilic hydrogel and micropapillaes result in an excellent underwater superhydrophobicity and low oil-adhesion characteristics. This mesh can display high stability and durability under various complex conditions and successfully remove water from various oil/water mixtures and exhibit a high separation efficiency (above 99%). We believe that even ordinary people without professional training can also prepare an efficient oil/water separation mesh easily through brushing the bicomponent hydrogel paint. Consequently, the bicomponent hydrogel paint could be an attractive commercial paint to fabricate oil/water separation mesh.