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Icephobic material is of great importance in power transportation, communication, aerospace, and so on. Bionic lotus superhydrophobic surfaces show good application prospects in anti‐icing by repelling impacting droplets. However, the boundary (criterion) between droplet bounce and deposition on superhydrophobic surface under cold freezing rain is unclear. Here, from the view of statistics, the boundary and internal heat transfer mechanism of the droplet bounce, pinning, and three kinds of deposition including icing at later, early retraction, and spread. are clarified Droplet viscosity increase reduces droplet contact with surface and inhibited splash at high We. Surfaces with temperature above −20.6 °C showed 100% droplet bounce after impact on We = 64.7, and the probability of water adhesion and ice nucleation decreases to ≈0%, resulting in completely anti‐icing. Droplet bounce transition mainly ascribe to the decrease retraction driven force caused by interface freezing and transition temperature increases approximately linearly from −25.9 to −21.1 °C within 21.6 < We < 75.5. Ice nuclei brought by condensation in humid environment (60–100 RH%) further cause droplet eccentric retraction and transition temperature increases to −6 to −10 °C. The fundamental understanding of droplet behaviors on supercooled superhydrophobic surface is beneficial for icephobic surfaces applications. [ABSTRACT FROM AUTHOR]

Droplet bouncing on special wettability surface is common and important in daily life and engineering applications (anti‐icing and drag reduction, etc.). However, there are few studies on the multiple droplets impact and there is a lack of systematic research on the interaction of oscillation and bounce. Here, the impact and oscillation of multiple droplets on the porous superhydrophobic bionic lotus surface are studied by a high‐speed camera system. On the bionic lotus surface (Surf‐1), an impacting droplet can merge another larger sessile droplet and bounce off. Comparing with single droplet impact, it is suggested that multiple droplets impact make more efficient use of the air cushion on the micrometer‐nanometer‐scale binary structure (MNBS) and show the self‐cleaning performance of Surf‐1 better. Moreover, with the theory for damped harmonic oscillators, it is found that Surf‐1 can prolong the oscillation of droplets (last >250 ms) and slow down the attenuation of energy. The energy can be efficiently recycled to the bounce by shortening the droplet impact interval (ti). The fundamental understanding of multiple droplets impact and the reclamation of oscillating energy are beneficial for scientific design of new surface and engineering applications. [ABSTRACT FROM AUTHOR]

Bionic self‐cleaning coatings have exhibited scaling inhibition for their low surface free energy. The key issue is focused on the long‐term anti‐scaling performance for the hydrophobicity failure after scaled. Inspired by "grass‐to‐stone" phenomenon, we reported a polymer coating (WCA = 120°, WSA = 14°) with the water contact angle of its 720 h‐scaled surface increased to 135°and scaling reduced by 90–95%. The nucleation and growth of CaCO3 at "coating‐crystal" interface are investigated, and a physical model for self‐healing film interface inhibiting scaling is innovatively proposed, as an important step toward designing long‐term anti‐scaling coating for engineering application. [ABSTRACT FROM AUTHOR]

Bionic self-cleaning surfaces with well-ordered polymer nano-fibers are firstly fabricated by disturbing crystallization during one-step coating-curing process. Orderly thin (100 nm) and long (5-10 μm) polymer nano-fibers with a certain direction are fabricated by external macroscopic force ( F) interference introduced by H gas flow, leading to superior superhydrophobicity with a water contact angle (WCA) of 170° and a water sliding angle (WSA) of 0-1°. In contrast, nano-wires and nano-bridges (1-8 μm in length/10-80 nm in width) are generated by 'spinning/stretching' under internal microscopic force ( F) interference due to significant temperature difference in the non-uniform cooling medium. The findings provide a novel theoretical basis for controllable polymer 'bionic lotus' surface and will further promote practical application in many engineering fields such as drag-reduction and anti-icing. [ABSTRACT FROM AUTHOR]