Nano-Capillary Bridges Control the Adhesion of Ice: Implications for Anti-Icing via Superhydrophobic Coatings

Abstract

Understanding the ice adhesion mechanism is vital for efficient anti-icing. However, previous studies focused on the adhesion of already sintered ice-solid contacts. Here, we study the adhesion mechanism between preformed ice and solid surfaces. In particular, we investigate the initial stages of ice adhesion. We find that capillary bridges formed by the quasi-liquid layer on the ice surface enhance ice adhesion. The adhesion force showed a maximum around −2 °C. Our model indicates that the nano-scaled curvature of the capillary bridge gives rise to strong adhesion forces in the temperatures between −5 and 0 °C. The capillary bridge expands and consolidates over time, causing an increase of adhesion force. These findings provide new physical insights into the ice adhesion mechanism with strong implications to the development of water-repellent superhydrophobic coatings for efficient anti-icing of solid surfaces.

A Fluorine-Free Superhydrophobic Micro–Nano Structured SiO2/TiN Coating for Anti-icing and Photothermal Deicing

“…A superhydrophobic surface offers an effective way to delay the icing time. − This is based on the presence of an air layer within the surface textures, which can greatly reduce the contact areas between water droplets and solid substrate. − The introduction of photothermal materials into superhydrophobic coating can effectively convert solar energy into thermal energy and promote the ice melting at the interface and then the removal of unmelted ice by gravity or superhydrophobicity. − Liu and co-workers constructed an all-water-based superhydrophobic coating by using carbon nanotubes, polydopamine, and Ag particles as photothermal materials and then mixing them in fluorine-containing polyacrylic emulsion . Under the irradiation of a xenon lamp, the melting time of the ice cubes on the coating surface was reduced by 982 s. Apart from the commonly used carbon-based materials and black metal oxides, − low-cost titanium nitride (TiN) nanoparticles have been proven recently to possess a plasmonic effect that can be used for photothermal conversion. ,− Wang’s groups have fabricated a flexible photothermal coating by embedding TiN nanoparticles in polydimethylsiloxane solution .…”

Superhydrophobic Hexadecyltrimethoxysilane-Modified Fumed Silica Nanostructure/Poly(butyl methacrylate) Composite Thin Films via Aerosol-Assisted Deposition: Implications for Self-Cleaning Surfaces

“…Superhydrophobicity arises due to two important factors, namely, (1) surface chemistry and (2) surface nano- and microroughness. The careful control of these two parameters has enabled the development of artificial SH materials that have applications in, for example, self-cleaning surfaces, oil–water separation, and anti-fogging materials. − …”