The ability to allow microliquid to penetrate in one direction but block in the opposite direction plays an irreplaceable role in intelligent liquid management. Despite much progress toward facilitating directional transport by multilayer porous membranes with opposite wettability, it remains difficult to achieve a highly multifunctional flexible membrane for highly efficient unidirectional liquid transport in different situations. Herein, a superhydrophilic–hydrophilic self-supported monolayered porous poly­(ether sulfone) (PES) membrane with special nano- and micropores at opposite surfaces is demonstrated, which can be used for unidirectional liquid transport. The results reveal that the competition of liquid spreading and permeation is critical to achieve directional liquid transport. The porous PES membrane, transformed with 70 vol % of ethanol in water (E/W-PES-70%), exhibits continuous unidirectional liquid penetration and antigravity unidirectional ascendant in a large range of pH values and can be used as “liquid diode” for moisture wicking. Moreover, the PES membrane can be prepared in a large area with excellent flexibility at room and liquid nitrogen temperature, indicating great promise in harsh environments. This work will provide an avenue for designing porous materials and smart dehumidification materials, which have promising applications in biomedical materials, advanced functional textiles, engineered desiccant materials, etc.

Dynamic control of liquid wetting behavior on smart surfaces has attracted considerable concern owing to their important applications in directional motion, confined wetting and selective separation. Despite much progress in this regard, there still remains challenges in dynamic liquid droplet manipulation with fast response, no loss and anti‐contamination. Herein, a strategy to achieve dynamic droplet manipulation and transportation on the electric field adaptive superhydrophobic elastomer surface is demonstrated. The superhydrophobic elastomer surface is fabricated by combining the micro/nanostructured clusters of hydrophobic TiO2 nanoparticles with the elastomer film, on which the micro/nanostructure can be dynamically and reversibly tuned by electric field due to the electric field adaptive deformation of elastomer film. Accordingly, fast and reversible transition of wetting state between Cassie state and Wenzel state and tunable adhesion on the surface via electric field induced morphology transformation can be obtained. Moreover, the motion states of the surface droplets can be controlled dynamically and precisely, such as jumping and pinning, catching and releasing, and controllable liquid transfer without loss and contamination. Thus this work would open the avenue for dynamic liquid manipulation and transportation, and gear up the broad application prospects in liquid transfer, selective separation, anti‐fog, anti‐ice, microfluidics devices, etc.

Design and construction of special surface microstructures has made many amazing breakthroughs in directional liquid transport. Despite much progress in this field, challenges still remain in on-demand switchable direction transport of liquid in situ and real-time via transforming the arrangement of the surface microstructure and external stimuli. Herein, we demonstrate a strategy to achieve switchable direction transport of liquid via a tunable anisotropic microarray surface, that is, assembling a V-shaped prism microarray (VPM) surface, which can also be intelligently manipulated by thermal stimuli. By transforming the parallel and staggered prism microstructure arrangement of the VPM, switchable direction transport of a liquid can be successfully achieved on the VPM surface. Flow direction switching among unidirectional transport, bidirectional transport, and reverse unidirectional transport is also achieved on the temperature-adaptive VPM surface by thermal stimuli, which can be used for on-demand liquid transport according to the paths of the microfluidic channels. The work provides a way for precise liquid manipulation in desired liquid transport, which may be utilized in nonpower conveying systems, autolubrication, life fluid medical instruments, and other microfluidic devices.

Directional droplet manipulation is very crucial in microfluidics, intelligent liquid management, etc. However, excessive liquid pressure tends to destroy the solid–gas–liquid (SAL) composite interface, creating a highly adhesive surface, which is not conducive to liquid transport. Herein, we propose a strategy to enhance the surface durability, in which the surface cannot withstand liquid pressure only by “blocking” but must instead guide liquid transport for “decompression”. Learning from the water resistance of water strider legs and the drag reduction of shark skin, we present a continuous integrated system to obtain an ultrastable super-hydrophobic surface with a highly ordered scaly structure via a liquid flow-induced alignment method for lossless unidirectional liquid transport. The nonwetting scaly structure can both buffer liquid pressure and drive droplet motion to further reduce the vertical pressure of the liquid. Moreover, droplets can be manipulated unidirectionally using a voice. This work could aid in manufacturing scalable anisotropic micro-nanostructure surfaces, which inspires efforts in realizing lossless continuous liquid control on demand and related microfluidic applications.

Direction-controlled wetting surfaces, special for lubricating oil infused anisotropic surfaces, have attracted great research interest in directional liquid collection, expelling, transfer, and separation. Nonetheless, there are still existing difficulties in achieving directional and continuous liquid transport. Herein, we present a strategy to achieve directional liquid transport on transparent lubricating oil infused elastomer film with V-shaped prisms microarray (VPM). The results reveal that the water wetting direction in the parallel and staggered arrangement of the VPM structure surface with lubricating oil infusion is the opposite, which is completely different from the wetting direction on the usual VPM surface in air. Moreover, asymmetric stretching can enhance or weaken the directional water wetting tendency on the lubricating oil infused VPM elastomer film and even can reverse the droplet wetting direction. In a closed moist environment, tiny droplets gradually coalesce and then slip away from the lubricating oil infused VPM surface to keep the surface transparent, due to the cooperation of imbalanced Laplace pressure, resulting from the anisotropic geometric structures, varying VPMs spacing, and gravity. Thus, this work provides a paradigm to design and fabricate a type of surface engineering material in the application fields of directional expelling, liquid collection, anti-biofouling, anti-icing, drag reduction, anticorrosion, etc.

Gallium-based liquid metal (LM) is one of the promising materials in design of microfluidic device and electrical components. Although much progress has been made, it is still challenging to achieve...

It reviews the most recent progress in detection, treatment, and recycling of contaminants mainly from wastewater using iron triad nanomaterials.

Controllable liquid transportation through smart porous membrane is expected by manipulating the surface wetting properties and external stimuli, which has been intensively studied. However, the liquid transportation, e.g., permeation and...