Abstract
The diffusion of gas from superhydrophobic surfaces (SHS) into liquid significantly limits their application. Although temperature is known to affect the diffusion coefficient of gases in liquids, its effect on the longevity of SHS remains poorly understood. In this work, the effect of temperature on the diffusion of gas from SHS to liquid and the SHS longevity was investigated. SHS with three types of texture geometries - holes, posts, and grooves - were tested over a temperature range of 3–35 °C. The diffusion induced wetting process and SHS longevity were measured by an optical method. Results showed that the SHS longevity decreased by a factor of 3–5, depending on the texture geometry, as temperature increased from 3 to 35 °C. Moreover, the experimental data had an excellent agreement with an analytical model based on one-dimensional gas diffusion and Eyring relationship between diffusion coefficient and temperature. This agreement suggests that higher temperatures increase the diffusion coefficient, which in turn enhances the gas mass flux from the SHS to the liquid, ultimately shortening SHS longevity. This work provides a theoretical framework for designing and implementing SHS in liquids across a wide range of temperatures, such as those encountered in marine environments.
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•Gas diffusion-induced wetting for superhydrophobic surface was measured.•Longevity of superhydrophobic surface decreases with increasing temperature.•A gas diffusion model was developed and captured the effect of temperature.