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

TL;DR

A new durable coating design improves deicing performance using acoustic waves, making it suitable for harsh environments like aviation and wind turbines.

Contribution

A bilayer DLC-CFx coating is introduced to enhance the stability and deicing efficiency of piezoelectric SAW devices.

Findings

The DLC-CFx bilayer coating protects ZnO surfaces while maintaining optimal SAW transmission.

The coating enables effective deicing through interfacial ice melting and rapid ice detachment.

The coating ensures long-term stability of acoustic wave devices in harsh outdoor conditions.

Abstract

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
x
layer (DLC-CF
x
). 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
x
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
x
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
x
through a room temperature
plasma-assisted method ensures reliability and long-term stability
of thin-film-based acoustic wave devices in harsh outdoor conditions.

Figures