A New Composite Material with Energy Storage, Electro/Photo-Thermal and Robust Super-Hydrophobic Properties for High-Efficiency Anti-Icing/De-Icing.

All weather, high-efficiency, energy-saving anti-icing/de-icing materials are of great importance for solving the problem of ice accumulation on outdoor equipment surfaces. In this study, a composite material with energy storage, active electro-/photo-thermal de-icing and passive super-hydrophobic anti-icing properties is proposed. Fluorinated epoxy resin and MWCNTs/PTFE particles are used to prepare the top multifunctional anti-icing/de-icing layer, which exhibited super-hydrophobicity with water contact angle greater than 155° and conductivity higher than 69 S m-1 . The super-hydrophobic durability of the top layer is verified through tape peeling and sandpaper abrasion tests. The surface can be heated by applying on voltage or light illumination, showing efficient electro-/photo-thermal and all-day anti-icing/de-icing performance. The oleogel material at the bottom layer is capable to absorb energy during heating process and release it during cooling process by phase transition, which greatly delayed the freezing time and saved energy. The icing test of single ice droplet, electro-/photo-thermal de-icing and defrosting tests also proved the high efficiency and energy saving of the anti-icing/de-icing strategy. This study provided a new way to manufacture multi-functional materials for practical anti-icing/de-icing applications.

Fracture-Promoted Ultraslippery Ice Detachment Interface for Long-Lasting Anti-icing.

Ice accumulation on surfaces significantly jeopardizes the operational security and economic effectiveness of equipment. As one of the efficient anti-icing strategies, fracture-induced ice detachment strategy can realize low ice adhesion strength and is feasible for large-area anti-icing, but its application in harsh environment is restrained by mechanical robustness deterioration due to ultralow elastic moduli. It is still a challenge for fracture-promoted interfaces to reach ultralow ice adhesion and maintain strong mechanical robustness. Drawing inspiration from subcutaneous tissue, we propose a multiscale interpenetrating reinforcing method to develop a fracture-promoted ultraslippery ice detachment interface. Our approach minimizes elastic deformation and the stress threshold of fracture initiation during ice detachment, ensuring fast and noninjurious ice detachment on the interface. At the same time, this method reinforces the mechanical robustness of the fracture-promoted ultraslippery interface, making it possible to ensure long-term operation under harsh conditions. The superiority is revealed by ultralow ice adhesion strength below 20 kPa at -30 °C even after 200 continuous abrasion cycles, as well as efficient ice shedding during dynamic anti-icing tests, which is clarified by theoretical prediction and experimental verification. This work is expected to enlighten the design of next-generation durable anti-icing interface.

Highly Efficient Multiscale Fog Collector Inspired by Sarracenia Trichome Hierarchical Structure.

Fog harvesting through bionic strategies to solve water shortage has drawn considerable attention. Recently, an ultrafast fog harvesting and transport mode was identified in Sarracenia trichome, which is mainly attributed to its superslippery capillary force induced by its unique hierarchical microchannel. However, the underlying effect of hierarchical microchannel-induced ultrafast transport on fog harvesting and the multiscale structural coupling effect on highly efficient fog harvesting are still great challenges. Herein, a bionic Sarracenia trichome (BST) with an on-demand regular hierarchical microchannel is designed using a one-step thermoplastic stretching approach on a glass fiber bundle. The BST is engineered to harbor major channels confined by an inner gear pattern along with junior microchannels that are automatically assembled by the glass fiber monofilaments. The BST shows enhanced capillary condensation and fog harvesting performance, in part due to its coupling effect with a Janus membrane (JM). Hence, a highly efficient multiscale fog collector is developed, in which a gradient high-pressure field is purposely formed to improve by threefold fog harvesting performance compared with a single-scale structure. This easy manufacturing and low-cost fog collector may represent a useful tool for harvesting fog water for production and living and pave the way for further investigations.

Polysulfide microspheres with chemical modification for generation of interfaces with macroscopic colour variation and biomimetic superhydrophobicity.

Both superwettability and structural colours have attracted considerable attention in recent years. In addition, the combination of structural colours and superwettability could endow materials with broader application prospects. The combination provides a new strategy to design novel functional materials, and there are many studies pertaining to these materials that have been reported in recent years. Herein, a polysulfide (PSF) superhydrophobic coating was synthesized successfully. The PSF superhydrophobic coating possesses excellent superhydrophobicity, oleophobicity for diesel and macroscopic structural colour variation when wetted. The colour is changed when the coating is wetted and it returns to its original colour after drying. In addition, the surface presents better reusability and thermostability which satisfies various daily needs. The PSF superhydrophobic coating can be considered as an excellent candidate for designing wetting responsive materials, and it has enormous application potential in the fields of detection, sensing, anti-counterfeiting and security. For the first time, we present a novel and low-cost strategy to fabricate materials with both superhydrophobicity and structural colour, offering significant insights into the practical application of these functional materials.

Biomimetic self-slippery and transferable transparent lubricant-infused functional surfaces.

Self-slippery liquid-infused porous surfaces (SLIPSs) have been presented owing to their enormous number of potential applications and have widely attracted the attention of researchers in recent years. In comparison with superhydrophobic surfaces, SLIPSs not only exhibit interfacial performance that corresponds to superhydrophobicity but also do not require the construction of a complicated and delicate morphology. Here, a facile strategy has been proposed for constructing silica SLIPSs. Three common lubricants (perfluoropolyethers, liquid paraffin and ethyl oleate) were employed in this study. Using a facile brush process, the surface can be coated on a substrate, and, after infusion of the lubricant, the transformation from superhydrophobicity to self-slippage properties can be achieved. In addition, changing the kind of lubricant and adjusting the amount of nanoscale hybrid silica particles in the coating solution can modulate the surface transparency and interfacial characteristics, which makes the surface meet the various requirements of different service conditions. This transferable performance endows the surface with the possibility of meeting the various requirements of different conditions and demonstrates the enormous value of the application of the coatings in many fields.

Diving-floating locomotion induced by capturing and manipulating bubbles in an aqueous environment.

A superhydrophobic and superaerophilic surface was fabricated by facile self-assembly of silica nanoparticle/PDMS composites. The relevant superaerophilic surface showed excellent adhesion to air bubbles in an aqueous environment. With bubbles adhering to the superaerophilic surface, the density of the whole system was adjustable, which was applied to induce a diving-floating locomotion in an aqueous environment.

Novel fabrication of polymer/carbon nanotube composite coated Janus paper for humidity stress sensor.

In this work, we constructed a sensing system on Janus paper with hydrophilic side and hydrophobic side via depositing polymer precursor onto one side of qualitative filter paper. Water in humid environment (including liquid water, condensed moisture airflow and gaseous humid atmosphere) will be captured and gathered in the hydrophilic region of Janus paper due to the asymmetric hydrophobicity and hygroscopicity, which can induce the novel directional deformation. Additionally, MWCNTs (multiwalled carbon nanotubes) were loaded onto hydrophobic region beforehand to construct conductive network. The resistance of the conductive network changes synergistically as the Janus paper deforms in humid environment. Thus, the novel Janus paper realized the induction of environment humid factors, and conversion from the deformation signals to the desirable electric signals. The Janus paper also shows excellent stability in cycle use.

Biomimetic superwettable materials with structural colours.

Structural colours and superwettability are of great interest due to their unique characteristics. However, the application of materials with either structural colours or superwettability is limited. Moreover, materials possessing both structural colours and superwettability are crucial for many practical applications. The combination of structural colours and superwettability can result in materials for use various applications, such as in sensors, detectors, bioassays, anti-counterfeiting, and liquid actuators, by controlling surfaces to repel or absorb liquids. Regarding superwettability and structural colours, surface texture and chemical composition are two factors for the construction of materials with superwettable structural colours. This review aims at offering a comprehensive elaboration of the mechanism, recent biomimetic research, and applications of biomimetic superwettable materials with structural colours. Furthermore, this review provides significant insight into the design, fabrication, and application of biomimetic superwettable materials with structural colours.