Bioinspired Fabrication of Hierarchical-Structured Superhydrophobic Surfaces To Understand Droplet Bouncing Dynamics for Enhancing Water Repellency

Dynamic water repellency refers to the capacity of droplets to rapidly detach from solid surfaces and is usually evaluated by the contact time; it has diverse applications, such as anti-icing, water proofing, self-cleaning, etc. Although various functional surfaces with nonwettability have been designed and fabricated to provide dynamic water repellency with a certain extent of application potential, the underlying physics of bouncing dynamics of impact droplets is still needed to be studied for more rational explanation of some special phenomena, especially under low-temperature conditions. On the basis of experimental studies and theoretical calculations, we analyzed the critical condition between rebounding and splashing of impact droplets on the hierarchical-structured superhydrophobic surfaces. Subsequently, the rebounding process was considered as the research object for revealing the action mechanism of triple-phase contact line on mediating the dynamic water repellency. All these physics will help to analyze the anti-icing mechanism of anti-icing/icephobic materials with the aim to well repel the coming supercooled droplets.