Multifunctional Superwetting Composite Coatings for Long‐Term Anti‐Icing, Air Purification, and Oily Water Separation

Abstract It is an important tendency to develop a durable superwetting coating for potential applications. However, its application, integration and evaluation mechanism in specific application environments are still inadequate toward practical applications. Herein, a universal approach to fabricate ultra‐stable and multifunctional superhydrophobic composite coating with superoleophobicity or superoleophilicity using cross‐linked composite resin as reinforcement is reported. The nano‐porous structure with extremely low surface energy is endowed with excellent mechanical stability, to greatly extend service life in the anti‐fouling, anti‐icing, air purification, and oily water separation fields. The anti‐icing tests show that the ice shear force is still below 20 kPa after the 200th finger wear, 30th abrasion tester wear, or 20th freeze–thaw cycle. For air purification, the weight increments from steam and dust are only 7.1% after moisturizing 240 min and 8% after filter‐cleaning five cycles, respectively. Moreover, the crude oil flux reaches up to 53 629 L·m −2 ·h −1 on the stainless steel wire treated with superhydrophobic–superoleophilic composite coating, and its separation efficiency is still above 99.5% after separating 55 cycles. These multiple key properties that have been integrated into the composite coating are expected to promote the superwetting coating to be used in everyday life and industry.