Fig. 5: Possible models of water wetting behavior changes over gradient nanostructures.
From: Gradient wettability induced by deterministically patterned nanostructures
a Schematic illustration of two classic wetting models, namely, Wenzel and Cassie, and two intermediate state models, where one has immersion depth h as the variable parameter, and the other has immersion ratio x as the variable parameter. b Contact angle at different positions of the COC film with a concentric gradient structure from the experiment and theoretical calculation of the Wenzel model and the Cassie model. c Comparison of the experimental contact angle and theoretically calculated possible range (the area with green dashed lines) of the intermediate state 1 model at each position from h = 0 nm to h = 199 nm (where the structure depth is 200 nm). d Comparison of the experimental contact angle and theoretically calculated possible range (the area with purple dashed lines) of the intermediate state 2 model at each position from x = 0 (where no groove is immersed in water) to x = 1 (where all grooves are immersed in water)
