Superoleophobicity of Fish Scales
Superoleophobicity of fish scales is a wetting phenomenon in which fish scales show oil repellency in water, with a static oil contact angle (CA) higher than 150°. Generally, underwater superoleophobicity is defined as a static oil CA higher than 150° on a solid surface in an oil/water/solid three-phase system.
Chemical and Physical Principles
Wettability is a fundamental property of solid surfaces, which not only affects the behavior of the creatures in nature but also plays an important role in all aspects of our life. A direct expression of wetting behavior is a static CA of a liquid droplet sitting on a solid surface when the surface tensions at multiphase interfaces reach thermodynamic equilibrium.