Acoustic Wave-Powered Durable Icephobic Duplex Coating Design with Superior Deicing Performance

Piezoelectric thin film-based surface acoustic wave (SAW) deicing technology has recently emerged as an attractive and energy-efficient alternative with direct applications across multiple industrial sectors. However, the generation of SAWs on piezoelectric thin films, such as ZnO, faces diverse challenges, including its low long-term stability and variable wetting properties upon exposure to UV radiation and other environmental hazards. To overcome these challenges, we propose a bilayer coating design that integrates a diamond-like carbon (DLC) thin film with an atop CF_<i>x</i> layer (DLC-CF_<i>x</i>). This design is intended to serve as both an anti-icing and a protective coating for ZnO SAW devices built on aluminum substrates, which are specifically selected for critical ice-exposed applications in the aeronautics or wind turbine industries. We demonstrate that, unlike the implementation of single fluorinated polymer layers, such as commercial CYTOP, the DLC-CF_<i>x</i> hydrophobic duplex coating effectively protects the ZnO surfaces while maintaining optimal SAW transmission and wave propagation and reducing the fluorine content. The SAW-induced deicing on these devices is achieved through a highly effective mechanism involving the interfacial ice melting, followed by a rapid ice sliding detachment for both small ice droplets and large ice aggregates. Experiments at laboratory scale and in an icing wind tunnel facility reveal that deicing involves SAW activation of the interface between the ice and the DLC-CF_<i>x</i> bilayer, as well as an effective thermal contribution resulting from the rapid heat transmission through the aluminum substrate. Our studies demonstrate that the highly conformal deposition of DLC-CF_<i>x</i> through a room temperature plasma-assisted method ensures reliability and long-term stability of thin-film-based acoustic wave devices in harsh outdoor conditions.