Pruney Finger-Inspired Switchable Surface with Water-Actuated Dynamic Textures

Switchable surfaces play an important role in the development of functional materials. However, the construction of dynamic surface textures remains challenging due to the complicated structural design and surface patterning. Herein, a pruney finger-inspired switchable surface (PFISS) is developed by constructing water-sensitive surface textures on a polydimethylsiloxane substrate by taking advantage of the hygroscopicity of the inorganic salt filler and the 3D printing technology. Like human fingertips, the PFISS shows high water sensitivity with obvious surface variation in wet and dry states, which is actuated by water absorption-desorption of the hydrotropic inorganic salt filler. Besides, when the fluorescent dye is optionally added into the matrix of the surface texture, water-responsive fluorescent emitting is observed, providing a feasible surface-tracing strategy. The PFISS shows effective regulation of the surface friction and performs a good antislip effect. The reported synthetic strategy for the PFISS offers a facile way for building a wide range of switchable surfaces.

Automated summary

Researchers developed a switchable surface inspired by human fingertips, which exhibits high water sensitivity and surface variation in wet and dry states. The surface is constructed by utilizing the hygroscopicity of inorganic salt filler and 3D printing technology. Addition of fluorescent dye in the surface texture enables water-responsive fluorescent emitting, serving as a surface-tracing strategy. This switchable surface offers effective regulation of surface friction and demonstrates good anti-slip effects. The synthetic strategy reported provides a facile way for constructing a wide range of switchable surfaces.