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Directed motion of liquid droplets is of considerable importance in various water and thermal management technologies. Although various methods to generate such motion have been developed at low temperature, they become rather ineffective at high temperature, where the droplet transits to a Leidenfrost state. In this state, it becomes challenging to control and direct the motion of the highly mobile droplets towards specific locations on the surface without compromising the effective heat transfer. Here we report that the wetting symmetry of a droplet can be broken at high temperature by creating two concurrent thermal states (Leidenfrost and contact-boiling) on a topographically patterned surface, thus engendering a preferential motion of a droplet towards the region with a higher heat transfer coefficient. The fundamental understanding and the ability to control the droplet dynamics at high temperature have promising applications in various systems requiring high thermal efficiency, operational security and fidelity. Controlled motion of a droplet on a hot surface is hampered by the formation of an evaporation layer below the droplet (Leidenfrost effect). But a cleverly patterned surface induces a Leidenfrost–contact-boiling state, directing the droplet’s motion.

Liquid metal (LM) has gained increasing attention for a wide range of applications, such as flexible electronics, soft robots, and chip cooling devices, owing to its low melting temperature, good flexibility, and high electrical and thermal conductivity. In ambient conditions, LM is susceptible to the coverage of a thin oxide layer, resulting in unwanted adhesion with underlying substrates that undercuts its originally high mobility. Here, we discover an unusual phenomenon characterized by the complete rebound of LM droplets from the water layer with negligible adhesion. More counterintuitively, the restitution coefficient, defined as the ratio between the droplet velocities after and before impact, increases with water layer thickness. We reveal that the complete rebound of LM droplets originates from the trapping of a thinly low-viscosity water lubrication film that prevents droplet-solid contact with low viscous dissipation, and the restitution coefficient is modulated by the negative capillary pressure in the lubrication film as a result of the spontaneous spreading of water on the LM droplet. Our findings advance the fundamental understanding of complex fluids’ droplet dynamics and provide insights for fluid control. Liquid metals are widely used in flexible electronics and soft robotics applications, but their adhesion to underlying solid substrates is unwanted. Dai et al. show that liquid metal droplets can overcome adhesion forces and bounce off from the surface covered with a water film with sufficient thickness.

Droplet impacting on solid or liquid interfaces is a ubiquitous phenomenon in nature. Although complete rebound of droplets is widely observed on superhydrophobic surfaces, the bouncing of droplets on liquid is usually vulnerable due to easy collapse of entrapped air pocket underneath the impinging droplet. Here, we report a superhydrophobic-like bouncing regime on thin liquid film, characterized by the contact time, the spreading dynamics, and the restitution coefficient independent of underlying liquid film. Through experimental exploration and theoretical analysis, we demonstrate that the manifestation of such a superhydrophobic-like bouncing necessitates an intricate interplay between the Weber number, the thickness and viscosity of liquid film. Such insights allow us to tune the droplet behaviours in a well-controlled fashion. We anticipate that the combination of superhydrophobic-like bouncing with inherent advantages of emerging slippery liquid interfaces will find a wide range of applications. The impact of drops on surfaces is highly relevant to our daily life and many industrial applications, such as self-cleaning and ink printing. Here, Hao et al . show the transition from superhydrophobic-like drop bouncing, due to a trapped air layer, to substrate-dependent bouncing on a liquid thin film.

Electrowetting on dielectric (EWOD) has emerged as a powerful tool to electrically manipulate tiny individual droplets in a controlled manner. Despite tremendous progress over the past two decades, current EWOD operating in ambient conditions has limited functionalities posing challenges for its applications, including electronic display, energy generation and microfluidic systems. Here, we demonstrate a new paradigm of electrowetting on liquid-infused film (EWOLF) that allows for complete reversibility and tunable transient response simultaneously. We determine that these functionalities in EWOLF are attributed to its novel configuration, which allows for the formation of viscous liquid-liquid interfaces as well as additional wetting ridges, thereby suppressing the contact line pinning and severe droplet oscillation encountered in the conventional EWOD. Finally, by harnessing these functionalities demonstrated in EWOLF, we also explore its application as liquid lens for fast optical focusing.

Soft robots, inspired by the flexibility and versatility of biological organisms, have potential in a variety of applications. Recent advancements in magneto-soft robots have demonstrated their abilities to achieve precise remote control through magnetic fields, enabling multi-modal locomotion and complex manipulation tasks. Nonetheless, two main hurdles must be overcome to advance the field: developing a multi-component substrate with embedded magnetic particles to ensure the requisite flexibility and responsiveness, and devising a cost-effective, straightforward method to program three-dimensional distributed magnetic domains without complex processing and expensive machinery. Here, we introduce a cost-effective and simple heat-assisted in-situ integrated molding fabrication method for creating magnetically driven soft robots with three-dimensional programmable magnetic domains. By synthesizing a composite material with neodymium-iron-boron (NdFeB) particles embedded in a polydimethylsiloxane (PDMS) and Ecoflex matrix (PDMS:Ecoflex = 1:2 mass ratio, 50% magnetic particle concentration), we achieved an optimized balance of flexibility, strength, and magnetic responsiveness. The proposed heat-assisted in-situ magnetic domains programming technique, performed at an experimentally optimized temperature of 120 °C, resulted in a 2 times magnetization strength (9.5 mT) compared to that at 20 °C (4.8 mT), reaching a saturation level comparable to a commercial magnetizer. We demonstrated the versatility of our approach through the fabrication of six kinds of robots, including two kinds of two-dimensional patterned soft robots (2D-PSR), a circular six-pole domain distribution magnetic robot (2D-CSPDMR), a quadrupedal walking magnetic soft robot (QWMSR), an object manipulation robot (OMR), and a hollow thin-walled spherical magneto-soft robot (HTWSMSR). The proposed method provides a practical solution to create highly responsive and adaptable magneto-soft robots. A cost-effective heat-assisted in-situ method enables 3D programmable magnetic domains in magneto-soft robots, while maintaining high-performance magnetic control. Optimized material composition ensures durability, adaptability, and enhanced magnetic actuation efficiency. We demonstrated the versatility of our approach through the fabrication of six kinds of robots capable of versatile deformations, locomotion, and the manipulation of both rigid and liquid object

Icing remains a major challenge in industrial and environmental applications, leading to efficiency losses, safety hazards, and substantial economic impacts. Conventional deicing methods are energy‐intensive and environmentally unsustainable, often requiring high energy inputs, extensive operational maintenance, or the use of harmful chemicals. These drawbacks underscore the need for advanced, scalable solutions that are both efficient and environmentally responsible. Here, the armored photothermal icephobic structured surface (APISS) is presented that combines superhydrophobicity and photothermal effects to deliver superior anti‐icing performance. The APISS consists hierarchical micro‐nanostructures with titanium nitride (TiN) nanoparticles encapsulated in a silica shell, ensuring exceptional durability and efficient solar energy conversion. Under 1 sun illumination, APISS achieves a temperature increase of 35 °C, effectively melting ice within 179 s and preventing refreezing. Its superhydrophobic properties facilitate the removal of melted water, maintaining a clean and dry surface. Comprehensive testing reveals that APISS significantly outperforms existing anti‐icing materials in scalability, durability, and sustainability, making it highly suitable for renewable energy, aviation, and infrastructure maintenance. The work highlights APISS as an advanced approach to anti‐icing technology, addressing critical challenges with a scalable and environmentally friendly solution. The armored photothermal icephobic structured surface (APISS) features a hierarchical micro‐nanostructured architecture optimized for enhanced solar absorption, coated with titanium nitride (TiN) nanoparticles to maximize photothermal conversion efficiency and silica encapsulation to ensure exceptional mechanical resilience. It offers a robust, efficient, and sustainable solution for mitigating icing across diverse applications.

Achieving rapid shedding of droplets from solid surfaces has received substantial attention because of its diverse applications. Previous studies have focused on minimizing contact times of liquid droplets interacting with stationary surfaces, yet little consideration has been given to that of moving surfaces. Here, we report a different scenario: A water droplet rapidly detaches from micro/nanotextured rotating surfaces in an intriguing doughnut shape, contributing to about 40% contact time reduction compared with that on stationary surfaces. The doughnut-shaped bouncing droplet fragments into satellites and spontaneously scatters, thus avoiding further collision with the substrate. In particular, the contact time is highly dependent on impact velocities of droplets, beyond previous descriptions of classical inertial-capillary scaling law. Our results not only deepen the fundamental understanding of droplet dynamics on moving surfaces but also suggest a synergistic mechanism to actively regulate the contact time by coupling the kinematics of droplet impingement and surface rotation.

Soft robots based on stimuli‐responsive materials, such as those responsive to thermal, magnetic, or light stimuli, hold great potential for adaptive locomotion and multifunctionality in complex environments. Among these, liquid crystal elastomers (LCEs) and magnetic microparticles have emerged as particularly promising candidates, leveraging their thermal responsiveness and magnetic controllability, respectively. However, integrating these modes to achieve synergistic multimodal actuation remains a significant challenge. Here, we present the thermo‐magnetic petal morphing robot, which combines LCEs with embedded magnetic microparticles to enable reversible shape morphing via remote light‐to‐thermal actuation and high‐speed rolling locomotion under external magnetic fields. The robot can achieve rapid deformation under near‐infrared light, transitioning from a closed spherical to an open cross‐like configuration with consistent shape recovery across multiple cycles, and demonstrates a maximum locomotion speed of 30 body lengths per second, outperforming many state‐of‐the‐art soft robots. Moreover, the robot's performance remains robust across dry, wet, and underwater conditions, with adjustable magnetic particle concentrations allowing tunable actuation performance. Our work addresses the need for soft robots with enhanced versatility and adaptability in complex environments, paving the way for applications in areas such as targeted drug delivery and industrial material handling. The thermo‐magnetic petal morphing robot (TMPMR) integrates liquid crystal elastomers with magnetic microparticles to achieve dual functionalities: thermal shape morphing and magnetic rolling locomotion. It demonstrates high‐speed motion, robust performance across diverse environments, and versatile cargo manipulation. This work highlights TMPMR's potential for biomedical applications such as targeted drug delivery and industrial material handling in complex scenarios.

Front Cover: The cover image is based on the Research Article Thermo‐magnetic soft robot for adaptive locomotion and delivery by Wang et al. Cover description: This cover illustrates a thermo‐magnetic soft robot integrating light‐responsive liquid crystal elastomers with embedded magnetic particles. The robot undergoes reversible petal‐like shape morphing under near‐infrared light and magnetically guided rolling locomotion. Demonstrating adaptive motion and delivery across diverse environments, it paves the way for versatile applications in biomedical transport, environmental sensing, and soft robotic systems. (DOI: 10.1002/dro2.70016)