fig3

Figure 3. Characterization of the robust superhydrophobic surface and environmental durability of the proposed sensor. (A) Schematic of the superhydrophobicity and air cushion in the Cassie-Baxter state; (B) Optical images showing a water droplet residing on the sensor surface (top view) and the microscopic roughness profile (cross-sectional view); (C) Long-term durability assessment showing the evolution of the θ_CA over 800 bending cycles (± 60°). The values are presented as mean ± SD; N = 3; (D) Variation of the θ_CA under dynamic uniaxial tensile strains ranging from 0% to 100%; (E) Tape-peeling test results displaying the evolution of θ_CA and θ_SA over repeated peeling cycles. The values are presented as mean ± SD; N = 3; (F) Sandpaper abrasion test characterization showing the retention of high θ_CA and low θ_SA values against friction-induced wear. The values are presented as mean ± SD; N = 3; (G) High-speed water-jet impact test demonstrating resistance to dynamic liquid pressure, with minimal degradation in θ_CA/θ_SA values after impact; (H) UV-light irradiation test simulating resilience against long-term outdoor aging; (I) Optical images of various complex fluids, including water, milk, juice, and acid, alkali, and salt (simulating seawater) solutions, maintaining spherical shapes on the sensor surface. θ_CA: Contact angle; θ_SA: sliding angle; SD: stand deviation; UV: ultraviolet.