If a superhydrophobic surface is immersed in water, some gas will be captured by the surface. Here comes the question that how thick is the gas layer? I know that it correlates with the immerse height, but what's the relation between them?
In some references, the thickness of the gas layer on a superhydrophobic surface when immersed in water is about 50 μm. However, in our experiments, we measured that the thickness is only about 18 μm. Other tests are needed to confirm it.