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A kind of superhydrophobic magnetic nano/micropillar array (MNA) with optimized intrinsic dynamic wetting property has characteristics of magnetically induced dynamic tilt‐angle changes, which achieves the controlling of the directional droplet transport effectively. It is revealed that MNA has a low adhesive gradient along the direction of magnetically induced tilt‐angles. A tilt‐angles of nano/micropillars in the range of 0°–59° is realized by controlling the magnetic field intensity (0–490 mT), so that a droplet (10 µL) can be transported on MNA from one pillar to the next along the tilt‐angle direction. It is proposed that the continuous changes of magnetically induced dynamic tilt‐angles on MNA induce a gradient driving force to act on the droplet, in addition to cooperation with the low adhesive direction that results from unidirectional gradient discontinuous solid–liquid–gas three phase contact lines. The finding offers insight into designing of surface materials that can be extended into microfluidics for controlling of droplet motion and others.

A photoresponsive organogel surface (POS), which integrates characteristics of the photothermal property of Fe 3 O 4 nanoparticles and the low hysteresis feature of lubricant-infused organogels, is shown. A photothermally induced dynamic temperature gradient can be formed rapidly at the location of nearinfrared-light irradiation (NIR) on POS with suitable Fe 3 O 4 nanoparticles content. Thus, various droplets (e.g., water, glycerol, ethylene glycol, propylene glycol, and ethanol) can be transported effectively and nimbly (e.g., along desired trajectories with controllable velocity and direction, even run uphill and deliver solid particles). This work reveals a synergistic effect between the asymmetrical droplet deformation and the inside Marangoni flows, which forms a unique driving force for droplet transport with high efficiency. This finding offers insight into the design of novel responsive interface materials for droplet transportation, which would be significant for laboratory-on-a-chip contexts, mass transportation, and microengines.

An artificial periodic roughness-gradient conical copper wire (PCCW) can be fabricated by inspiration from cactus spines and wet spider silks. PCCW can harvest fog on periodic points of the conical surface from air and transports the drops for a long distance without external force, which is attributed to dynamic as-released energy generated from drop deformation in drop coalescence, in addition to both gradients of geometric curve (inducing Laplace pressure) and periodic roughness (inducing surface energy difference). It is found that the ability of fog collection can be related to various tilt-angle wires, thus a fog collector with an array system of PCCWs is further designed to achieve a continuous process of efficient water collection. As a result, the effect of water collection on PCCWs is better than previous results. These findings are significant to develop and design materials with water collection and water transport for promising application in fogwater systems to ease the water crisis.

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