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Fiber‐based multimodal sensors with electrical/optical signals are highly desired for next‐generation wearable electronics. Despite the remarkable progress in this area, achieving large‐scale knittable, washable, and self‐healing performance in fiber‐based multimodal sensors simultaneously remains a great challenge. Here, a smart fiber capable of exhibiting piezoresistive/luminescent properties based on an H‐bonding connected multilayered core–shell nanostructure is developed. The core principle of this design involves constructing strong interfacial interactions between the fiber layers, which results in a sensor with high sensitivity (gauge factor = 12383500), exceptional water resistance, and robust self‐healing properties (tensile strength 30.9 MPa, healing efficiency 72.9%). Unlike traditional fiber‐based sensors where elaborate nanostructures are prone to shedding during knitting, this strategy enables the fiber sensors with excellent knittability to be patterned in the fabric, improving both optical and electrical sensitivities. This work is anticipated to make a significant contribution to the further development of wearable electronic products and visual human–computer interaction electronic devices. [ABSTRACT FROM AUTHOR]

Cellulose nanocrystal (CNC) based optical devices with adjustable schemochrome have attracted immense interest. However, most of the previously reported structural colored CNC‐based materials can only achieve simple stress‐induced color change, which have difficulty achieving multimode control of complex patterning that can be accurately identified. Here, inspired by the nanostructure‐based color‐changing mechanism of neon tetra, this study presents a pressure/temperature dual‐responsive CNC‐based schemochrome hydrogel with adjustable dynamic chiral nematic structure. By incorporating abundant interfacial noncovalent interactions, dynamic correlations between adjustable helical pitch of the vertically stacked cholesteric liquid crystalline (LC) phase and responsiveness of flexible thermosensitive substrate are established, which further enable wide‐range optical characteristic (12°–213° in HSV color model and 421–734 nm in the UV–Vis spectra) and identifiable visualized patterning. The resultant hydrogels are applied in proof‐of‐concept demonstrations of on‐demand schemochrome patterning, including customizable patterned dual‐encryption label, smart digital display, temperature monitor, and intelligent recognition/control system. This study envisages that the bioinspired construction of structural colored nanomaterials will have promising applications in smart responsive photonic equipment including smart display, anticounterfeiting, and intelligent control systems. [ABSTRACT FROM AUTHOR]

Smart fluorescent materials that can respond to environmental stimuli are of great importance in the fields of information encryption and anti‐counterfeiting. However, traditional fluorescent materials usually face problems such as lack of tunable fluorescence and insufficient surface‐adaptive adhesion, hindering their practical applications. Herein, inspired by the glowing sucker octopus, we present a novel strategy to fabricate a reversible fluorescent eutectogel with high transparency, adhesive and self‐healing performance for conformal information encryption and anti‐counterfeiting. Using anthracene as luminescent unit, the eutectogel exhibits photoswitchable fluorescence and can therefore be reversibly written/erased with patterns by non‐contact stimulation. Additionally, different from mechanically irreversible adhesion via glue, the eutectogel can adhere to various irregular substrates over a wide temperature range (−20 to 65 °C) and conformally deform more than 1000 times without peeling off. Furthermore, by exploiting surface‐adaptive adhesion, high transparency and good stretchability of the eutectogel, dual encryption can be achieved under UV and stretching conditions to further improve the security level. This study should provide a promising strategy for the future development of advanced intelligent anti‐counterfeiting materials. [ABSTRACT FROM AUTHOR]

Imitating mechano‐sensing luminescence of organisms has long been envisaged to achieve dynamic and real‐time visualized information display, however, it remains challenging to recreate the skin‐like visual sensation functions in artificial sensors. Here, a bioinspired mechanosensor is presented with mechanoluminescent/triboelectric hierarchical structure that is capable of pressure perception and patterning display in real time. Interestingly, a facilitative effect of interfacial triboelectric field on luminescent output and pressure visualization was found. The developed mechanosensor shows self‐powered, bimodal, and real‐time patterning sensation behavior with a low force detection limit (0.082 N), high sensitivity (9.69 a.u. N−1), fast response (35 ms), and good reliability (5000 cycles). On this basis, an intelligent control system is further constructed via combining image machine learning approach. This study not only addresses the long‐lasting challenge of real‐time pressure visualized display, but also boosts the further development of untethered, small‐scale, and efficient intelligent systems. [ABSTRACT FROM AUTHOR]

Artificial materials with biomimic self‐healing ability are fascinating, however, the balance between mechanical properties and self‐healing performance is always a challenge. Here, a robust, highly stretchable self‐healing elastomer with dynamic reversible multi‐networks based on polyurethane matrix and cyclodextrin‐assembled nanosheets is proposed. The introduction of cyclodextrin nano‐assemblies with abundant surface hydroxyl groups not only forms multiple interfacial hydrogen bonding but also enables a strain‐induced reversible crystalline physical network owing to the special nanoconfined effect. The formation and dissociation of a dynamic crystalline physical network under stretching–releasing cycles skillfully balance the contradiction between mechanical robustness and self‐healing ability. The resulting nanocomposites exhibit ultra‐robust tensile strength (40.5 MPa), super toughness (274.7 MJ m−3), high stretchability (1696%), and desired healing efficiency (95.5%), which can lift a weight ≈ 100 000 times their own weight. This study provides a new approach to the development of mechanically robust self‐healing materials for engineering applications such as artificial muscles and healable robots. [ABSTRACT FROM AUTHOR]

The hydrophobicity of biomimetic hydrophobic surfaces exhibits a correlation with droplet relative dimension. Nevertheless, the droplet relative dimension‐dependent wettability, contact angles, dynamic droplet bouncing behaviors need to be further investigated. This article focuses on the size effect of droplet relative dimension on the contact angles and dynamic behaviors of regular microcolumn and microstrip array surfaces, which were directly machined by low‐speed wire electrical discharge machining (WEDM‐LS). Specifically, the contact angles are measured with droplet relative dimension in a range from 29.8 to 298 on various structured surfaces. The dynamic droplet bouncing tests are based on a coincident falling height of 10 mm. The period time is also gradually shortened with the decreasing of droplet relative dimension, which indicated that the droplets with relatively larger relative dimensions are more difficult to overcome the adhesion of arrayed structures. Meanwhile, when the droplet relative dimension exceeded a critical value, the droplet failed to separate from the substrate due to the interface adhesion and the period time would be also shortened which attributed to less time consumption for the insufficient capillary force compared with the gravity. [ABSTRACT FROM AUTHOR]

Stimulus‐responsive materials with designable integrated functions bridge the intelligent systems in future lifestyles with the Internet of Things (IoT). The growing trend for IoT and corresponding advanced devices will involve a great number of electronic disposables, which may place heavy burdens on the environment. Here, an elaborately designed multistage responsive material is reported for real‐time, reversible light‐writing based on organized stage‐by‐stage responsive behaviors and polarity‐dependent physicochemical fluorescence response, where the stimulus is accurately delivered through a completely reversible "light‐heat‐fluorescence" pathway. The resulted materials can be pollution‐freely written by hand‐controlled near‐infrared laser within 5 s, spontaneously erased within 20 s, and exhibit excellent re‐writing ability (more than 5000 times while the variance of chromaticity coordinates <0.0008), which is difficult to achieve by traditional laser writing technologies. This study is a step toward high‐performance long‐life functional devices based on reversible multistage responsive materials for future IoT lifestyles. [ABSTRACT FROM AUTHOR]

The combination of complex perception, defense, and camouflage mechanisms is a pivotal instinctive ability that equips organisms with survival advantages. The simulations of such fascinating multi‐stimuli responsiveness, including thigmotropism, bioluminescence, color‐changing ability, and so on, are of great significance for scientists to develop novel biomimetic smart materials. However, most biomimetic color‐changing or luminescence materials can only realize a single stimulus‐response, hence the design and fabrication of multi‐stimuli responsive materials with synergistic color‐changing are still on the way. Here, a bioinspired multi‐stimuli responsive actuator with color‐ and morphing‐change abilities is developed by taking advantage of the assembled cellulose nanocrystals‐based cholesteric liquid crystal structure and its water/temperature response behaviors. The actuator exhibits superfast, reversible bi‐directional humidity and near‐infrared (NIR) light actuating ability (humidity: 9 s; NIR light: 16 s), accompanying with synergistic iridescent appearance which provides a visual cue for the movement of actuators. This work paves the way for biomimetic multi‐stimuli responsive materials and will have a wide range of applications such as optical anti‐counterfeiting devices, information storage materials, and smart soft robots. [ABSTRACT FROM AUTHOR]

High‐performance intelligent materials with unique stimulus‐responsive properties are highly desired in the future as the rapid development of intelligent systems for Internet‐of‐Things applications. During their long service life, the irregularity in external stimuli and repetitive motions always result in unavoidable permanent damages, where the self‐healing ability inspired by skin is indispensable and highly attractive. However, the introduction of supramolecular networks to achieve self‐healing ability based on reversible dynamic noncovalent bonds usually leads to relatively low strength, while the conflict between high mechanical properties and high self‐healing efficiency is still a great challenge. Moreover, the lack of efficient interfacial interaction between functional layer and self‐healable polymer matrix leads to a permanent function loss during the healing of matrix. Herein, a brief overview of self‐healable sensors and actuators based on recent strategies including multiple noncovalent interactions, covalent–noncovalent interactions, and interfacial supramolecular crosslinking is presented. The advantages and applications of high‐performance self‐healable sensors and actuators enabled by interfacial supramolecular crosslinking are discussed emphatically, and the conclusions and outlooks of self‐healable intelligent materials are presented. [ABSTRACT FROM AUTHOR]

The resource utilization of artificial marble wastes (AMWs) is urgently needed for environmental protection as a large amount of artificial marble are used as construction material. Nevertheless, it still remains challenging to achieve high performance of AMWs‐filled polymer composites due to their poor interfacial interaction with hydrophobic polyolefins. Here, the unsaturated resin residue on the surface of AMWs is employed to construct strong interfacial interaction with high‐density polyethylene (HDPE) matrix to prepare mechanically robust polymeric composites by use of titanate coupling agent. The mechanical properties (with a tensile strength of 28.6 MPa and a flexural strength of 27.7 MPa) of the resulting composites are comparable to or even better than those of raw calcium carbonate‐filled HDPE composites. This work will not only promote the recycling and reutilization of AMWs, but also provide a feasible way for value‐added application of other polymeric wastes, such as waste printed circuit board, waste artificial turf, and so on. [ABSTRACT FROM AUTHOR]

Microplastics are of increasing environmental concern as emerging contaminants worldwide. However, very limited studies are focused on the treatment of microplastics based on material design. Here, we propose a cut‐from‐the‐source strategy through incorporating graphene nanosheets (GNs) into thermoplastic polyurethane (TPU) to prepare high performance composites via melt‐processing. The effects and mechanism of GNs on microplastics release of TPU are first investigated. Benefiting from the barrier effect of GNs and the strong interfacial interaction, microplastics release of the obtained composites is effectively inhibited during oxidative degradation and the mechanical properties are simultaneously enhanced. This work provides a novel strategy for the source reduction of microplastics, inspiring the microplastics governance in the future. [ABSTRACT FROM AUTHOR]

Despite the tremendous advancement of intelligent robots, it remains a great challenge to integrate living organisms‐like multistimuli responsive actuation and excellent self‐healing ability into one single material system, which will greatly benefit and broaden the development of smart biomimetic materials. Herein, a novel self‐healable multistimuli responsive actuator is developed based on hierarchical structural design and interfacial supramolecular crosslinking. The resulting biomimetic actuator shows a record high photothermal efficiency (ηPT = 79.1%) and thermal conductivity (31.92 W m−1 K−1), and presents a superfast actuating response (near‐infrared light: 0.44 s; magnetic field: 0.36 s). In addition, the supramolecular crosslinking endows excellent self‐healing performance in both mechanical and actuating properties to the material. This biomimetic actuator with its hierarchical structure design provides great potential for various applications, such as artificial muscles, soft robotics, and biomedical microdevices. [ABSTRACT FROM AUTHOR]

Ultrathin and high‐performance electromagnetic interference (EMI) shielding materials are urgently demanded for modern microelectronic devices. 2D metal carbides (MXenes) are considered as a promising EMI shielding material due to its metallic conductivity. In this study, sodium alginate is applied as interlayer spacer for Ti3C2Tx nanosheets, which not only prevents the restacking of lamella structure but also serves as building blocks for the sponge‐like structure. Ultrathin Ti3C2Tx/calcium alginate (CA) aerogel films with sponge‐like structure and only tens of microns thickness are prepared through divalent metal ion induced crosslinking, vacuum‐assisted‐filtration induced self‐assembly, and freeze‐drying. Taking advantage of its sponge‐like structure, which facilitates the dissipation of incident electromagnetic waves through multireflection and scattering Ti3C2Tx/CA aerogel film, presents excellent EMI shielding effectiveness (54.3 dB) at a very low thickness of 26 µm. Furthermore, Ti3C2Tx/CA aerogel film shows an outstanding specific EMI shielding efficiency (17586 dB cm2 g−1), which is superior to most reported synthetic materials. The preparation of ultrathin Ti3C2Tx/CA aerogel film provides facile strategy for designing and fabricating high‐performance MXene‐based EMI‐shielding materials, which is highly desirable for various applications including aerospace and smart electronic devices. Ultrathin Ti3C2Tx/calcium alginate aerogel film with sponge‐like structure is prepared through divalent metal ion induced crosslinking, vacuum‐assisted‐filtration induced self‐assembly, and freeze‐drying, exhibiting excellent electromagnetic interference (EMI) shielding effectiveness (54.3 dB) and specific shielding efficiency (17 586 dB cm2 g−1) at a low thickness of 26 µm. This work provides a feasible strategy for designing and fabricating high‐performance MXene‐based EMI‐shielding materials. [ABSTRACT FROM AUTHOR]