Smart controlling on the bi-stable state of bio-inspired multifunctional coatings for anti-/de-icing applications

Outdoor equipment can suffer from functional failure in winter due to ice accumulation. Although functional materials are widely recognized as promising candidates for anti-icing and de-icing applications, ice inevitably accretes on surfaces at extremely low temperatures and high humidity. If surfaces display reversible superhydrophobic and slippery performance, similar to Lotus leaves and fish skin, it will significantly improve the anti-icing and de-icing performance. This study proposes a novel type of multifunctional coating that could smartly reverse between superhydrophobic and slippery properties on demand. The superhydrophobic coatings with diverse morphologies were obtained by employing different sizes and shapes of nanoparticles. Due to the low adhesion and photothermal properties, the superhydrophobic samples presented good freezing rain prevention and snow-melting performances by outdoor tests in winter. The samples with slippery surfaces were produced by infusing dodecane on the as-prepared superhydrophobic surface. Both the superhydrophobic and slippery surfaces can effectively propel the water droplets, prolong the freezing time and enhance ice removal performance in an extremely cold environment. Therefore, the coated samples with bi-stable states (i.e., superhydrophobic and slippery states) were successfully achieved with the potential to be widely applied under different service environments. This facile strategy will provide the possibility for developing novel materials with smart reversible wettability for anti-icing and de-icing applications.