Superhydrophobic coating with a micro- and nano-sized MnO2/PDMS composite structure for passive anti-icing/active de-icing and photothermal applications

Abstract

The formation and accumulation of ice can induce serious economic damage. Eco-friendly anti-icing/de-icing surfaces have been developed to address these problems. Superhydrophobic photothermal coatings have received significant attention in recent years, but an anti-icing/de-icing coating which is robust and facile to prepare is highly desired. Herein, a fluorine-free MnO₂/PDMS superhydrophobic coating was prepared using a facile spraying method. The excellent superhydrophobicity (water contact angle of 162.3°) and good self-cleaning properties were due to the surface microstructure of micron/nano-scale MnO₂ with the “lotus leaf effect”, while the coating was able to maintain efficient photothermal properties over time, with excellent passive anti-icing and active de-icing properties. In terms of mechanical durability, it was subjected to severe tests (sandpaper abrasion, tape-peeling, sand-washing, sonic treatment) and maintained good robustness. Based on the photothermal properties of MnO₂ and the superhydrophobicity of the coating, it could have multiple applications, such as personal thermal management, oil–water separation, and solar-steam generation. This study provides a potential anti-icing/de-icing coating for large-scale preparation and multiple practical applications.