Droplets impacting solid superhydrophobic surfaces is appealing not only because of scientific interests but also for technological applications such as water-repelling.Recent studies have designed artificial surfaces...Droplets impacting solid superhydrophobic surfaces is appealing not only because of scientific interests but also for technological applications such as water-repelling.Recent studies have designed artificial surfaces in a rigid–flexible hybrid mode to combine asymmetric redistribution and structural oscillation water-repelling principles,resolving strict impacting positioning;however,this is limited by weak mechanical durability.Here we propose a rigid–flexible hybrid surface(RFS)design as a matrix of concave flexible trampolines barred by convex rigid stripes.Such a surface exhibits a 20.1%contact time reduction via the structural oscillation of flexible trampolines,and even to break through the theoretical inertial-capillary limit via the asymmetric redistribution induced by rigid stripes.Moreover,the surface is shown to retain the above water-repelling after 1,000 abrasion cycles against oilstones under a normal load as high as 0.2 N·mm−1.This is the first demonstration of RFSs for synchronous waterproof and wearproof,approaching real-world applications of liquid-repelling.展开更多
Morphological transformation of surface structures is widely manifested in nature and highly preferred for many applications such as wetting interaction;however,in situ tuning of artificial morphologies independent of...Morphological transformation of surface structures is widely manifested in nature and highly preferred for many applications such as wetting interaction;however,in situ tuning of artificial morphologies independent of smart responsive materials remains elusive.Here,with the aid of microfluidics,we develop a pneumatic programmable superrepellent surface by tailoring conventional wetting materials(e.g.,polydimethylsiloxane)with embedded flexible chambers connecting a microfluidic system,thus realizing a morphological transformation for enhanced liquid repellency based on a nature‐inspired rigid‐flexible hybrid principle(i.e.,triggering symmetry breaking and oscillator coupling mechanisms).The enhancement degree can be in situ tuned within around 300 ms owing to pneumatically controllable chamber morphologies.We also demonstrate that the surface can be freely programmed to achieve elaborated morphological pathways and gradients for preferred droplet manipulation such as directional rolling and bouncing.Our study highlights the potential of an in situ morphological transformation to realize tunable wettability and provides a programmable level of droplet control by intellectualizing conventional wetting materials.展开更多
基金financially supported by the National Natural Science Foundation of China(U20A20299)Guangzhou Science and Technology Planning Project(202103000042)+3 种基金Guangdong Basic and Applied Basic Research Foundation(2019A1515011379)Guangdong Special Support Program(2017TX04N371)S&T Special Projects(SRPG22-020)Guangdong Enterprise Sci-tech Commissioner(GDKTP2020013400)。
基金supported by the National Natural Science Foundation of China(12002202)Young Elite Scientist Sponsorship Program by the China Association for Science and Technology(YESS20200403)State Key Laboratory of Mechanical System and Vibration(MSVZD202104).
文摘Droplets impacting solid superhydrophobic surfaces is appealing not only because of scientific interests but also for technological applications such as water-repelling.Recent studies have designed artificial surfaces in a rigid–flexible hybrid mode to combine asymmetric redistribution and structural oscillation water-repelling principles,resolving strict impacting positioning;however,this is limited by weak mechanical durability.Here we propose a rigid–flexible hybrid surface(RFS)design as a matrix of concave flexible trampolines barred by convex rigid stripes.Such a surface exhibits a 20.1%contact time reduction via the structural oscillation of flexible trampolines,and even to break through the theoretical inertial-capillary limit via the asymmetric redistribution induced by rigid stripes.Moreover,the surface is shown to retain the above water-repelling after 1,000 abrasion cycles against oilstones under a normal load as high as 0.2 N·mm−1.This is the first demonstration of RFSs for synchronous waterproof and wearproof,approaching real-world applications of liquid-repelling.
基金National Natural Science Foundation of China,Grant/Award Numbers:12002202,12121002Young Elite Scientist Sponsorship Program by the China Association for Science and Technology,Grant/Award Number:YESS20200403State Key Laboratory of Mechanical System and Vibration,Grant/Award Number:MSVZD202104。
文摘Morphological transformation of surface structures is widely manifested in nature and highly preferred for many applications such as wetting interaction;however,in situ tuning of artificial morphologies independent of smart responsive materials remains elusive.Here,with the aid of microfluidics,we develop a pneumatic programmable superrepellent surface by tailoring conventional wetting materials(e.g.,polydimethylsiloxane)with embedded flexible chambers connecting a microfluidic system,thus realizing a morphological transformation for enhanced liquid repellency based on a nature‐inspired rigid‐flexible hybrid principle(i.e.,triggering symmetry breaking and oscillator coupling mechanisms).The enhancement degree can be in situ tuned within around 300 ms owing to pneumatically controllable chamber morphologies.We also demonstrate that the surface can be freely programmed to achieve elaborated morphological pathways and gradients for preferred droplet manipulation such as directional rolling and bouncing.Our study highlights the potential of an in situ morphological transformation to realize tunable wettability and provides a programmable level of droplet control by intellectualizing conventional wetting materials.
