Recent developments in air-trapped superhydrophobic and liquid-infused slippery surfaces for anti-icing application

Anti-icing coating is one of the recent hot topics in industrial applications as well as from the academic viewpoint. Icing is one of the major problem on various substrates such as glass windows in buildings as well as vehicles, solar panels, wind turbine blades, airplanes, transmission lines, power towers, traffic signals, off-shore oil platforms, telecommunication antennas, and many others. Ice accumulation can significantly reduce the performance of the substrates and results in poor visibility. Recently, considerable attention is being paid on the naturally inspired superhydrophobic/icephobic surfaces by mimicking its surface property for the development of artificial self-cleaning superhydrophobic and ice-phobic surfaces. A good example is the lotus leaf surface where hierarchical micro and nano-scale rough structure covered by low surface energy coating layer on the leaf can repel water droplets and prevent ice accumulation. On superhydrophobic surfaces, impacting and condensed water droplets rolled off before freezing at subzero temperature. On the other hand, in slippery liquid-infused porous surface (SLIPS), the air pockets are replaced by immiscible lubricant film which can easily remove the accumulated ice without any damage to the surface. In this review article, we describe the recent progress in passive anti-icing coating materials and methodologies. Metal substrates, polymers, and nanoparticles/polymer composites are playing the major role in the development of anti-icing surface. So, the main goal of this review articles deals with the development of various synthetic routes of superhydrophobic anti-icing coating materials from metal substrates, polymers, and nanoparticles/polymer composites. In addition, the role of SLIPS in anti-icing coating and their use are also discussed.