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Mantis shrimps deliver one of the fastest strikes with their powerful dactyl clubs. The kinematic energy derived by a saddle storing and releasing mechanical energy with large deformation. As an exoskeleton, the toughness of saddles can achieve a remarkable value ≈15.28 ± 2.32 MJ m−3, which exceeds most bulk natural materials. The excellent toughness of saddles is mainly attributed to the synergy of the helical mineralized fiber architectures and interlaminar fibrils. The interlaminar fibrils connect adjacent mineralized fiber layers closely, enhancing the toughness through viscoelastic deformation during sliding and separating of adjacent layers. They further cooperate with rigid interlacing fiber structure induced by helical structure to transform little normal strain to large shear strain utilizing incompressibility of soft fibrils further to enhance strain energy for toughening. Inspired by unique laminated saddles, the laminate composites are designed with basalt fabrics achieving remarkable fracture toughness to solve the problem of delamination in traditional laminate composites with poor interlaminar toughness. The Mode I and Mode II interlaminar fracture toughness of bio‐inspired laminate composites respectively increase by 44% and 118% reaching 906.8 and 1394.6 J m−2, which provides an innovative bionic strategy for designing new generation structural engineering materials with excellent mechanical properties. [ABSTRACT FROM AUTHOR]

In recent years, an increasing number of passive radiative cooling materials are proposed in the literature, with several examples relying on the use of silica (SiO2) due to its unique stability, non‐toxicity, and availability. Nonetheless, due to its bulk phonon‐polariton band, SiO2 presents a marked reflection peak within the atmospheric transparency window (8‐13 µm), leading to an emissivity decrease that poses a challenge to fulfilling the criteria for sub‐ambient passive radiative cooling. Thus, the latest developments in this field are devoted to the design of engineered SiO2 photonic structures, to increase the cooling potential of bulk SiO2 radiative coolers. This review seeks to identify the most effective photonic design and fabrication strategies for SiO2 radiative emitters by evaluating their cooling efficacy, as well as their scalability, providing an in‐depth analysis of the fundamental principles, structural models, and results (both numerical and experimental) of various types of SiO2 radiative coolers. [ABSTRACT FROM AUTHOR]

Flexible strain sensors are indispensable components providing repeatable electronic signals responding to mechanical deformations. Nevertheless, there is a stringent demand for flexible sensors to maintain normal performance in daily use and even in harsh conditions, such as high humidity and high temperature. Herein, inspired by scorpions, a highly sensitive flexible strain sensor based on ceramic fiber paper (CFP) with superhydrophobic and high‐temperature‐resistant properties is developed by a combination of mechanical cutting and spray coating method, which minimizes performance degradation commonly seen in polymer‐based and textile‐based sensors under harsh conditions. The prepared strain sensor exhibits high sensitivity (gauge factor ≈1254), low detection limit (0.078%), fast response time (108 ms), and notable stability (over 10 000 cycles). The ultra‐high sensitivity originates from the existence of the micro‐scale cracks. To further improve stability of the device in some harsh conditions, superhydrophobic and heat‐resisting coatings consisting of SiO2 aerogels and SiO2 nanoparticles are introduced onto the surface of CFP. Owing to the synergistic effect of the high‐temperature resistance of ceramics fibers and the coatings, the device operates normally at temperature up to 220 °C with a water contact angle of 159°, showing great promises for harsh conditions, especially in the industrial and aerospace fields. [ABSTRACT FROM AUTHOR]

The high‐performance optimized design of industrial sensor has been a challenging point of breakthrough in high‐end equipment manufacturing technology since its invention. Highly sensitive detectors have emerged during a long evolutionary period and have shown to be essential tools for ensuring species survival and reproduction. As a result, bio‐sensors have served as a great source of inspiration for high‐sensitivity and high‐performance sensor. Mechanism of bio‐sensors in mechanical detection of three common arthropods, as well as the most recent research results in bio‐mimetic devices, have been discussed in this study. The structure of bio‐detectors and bio‐sensors has been creatively split into environmental information capture device and transduction unit from the standpoint of biological sensing mechanisms and engineering technology. And development of bio‐sensors will rely on design and exploitation of mechanical structures and functional materials with various couplings. Exploration of bionic mechanical sensors is in its early stages and further research is required. High‐performance research on biological detectors and multi‐level bionic design on industrial sensors have been enhanced by revealing mechanism of environmental information capture in environment capture device from basic science and synthesizing new multi‐functional materials of transduction unit with a combination of biological materials and production technology. [ABSTRACT FROM AUTHOR]

Flexible sensors, as a kind of indispensable branch of flexible electronics, are garnering substantial in medical and industrial applications. Ever‐evolving advances in nanowires in their myriad forms have fueled many of the developments in this field. However, recent researches have extensively focused on the intrinsic properties of these nanomaterials, rationally designed structures, which are pivotal in sensing performance, to a large extent, are undervalued. Hereon, the latest advances in the structure design, together with controlled fabrication of nanowires for better sensing performance are highlighted. In specific, nanowires are classified according to morphologies and hybrid forms and their corresponding fabrication methodologies and influence on sensing properties are briefly discussed. Then, construction strategies for nanowire‐based sensors, including materials assembly and macroscopical design are systematically summarized. Subsequently, the characteristics and advantages of flexible sensors induced by various nanowires, including physical/physiological/multifunctional parameters sensing are reflected in the application examples. Finally, conclusions and challenges are presented for the development of nanowire‐based flexible sensors, as well as frontier strategies especially bionic design. This review is aimed at providing a valuable and systematic understanding of nanowires in sensing system and then serves as inspiration for intelligent designs in flexible future electronics. [ABSTRACT FROM AUTHOR]

In recent years, there has been an increasing interest in the novel bioinspired sensors, especially for their selectivity, response time, and sensitivity. Particular attention is paid to the novel optical functional materials that are crucial for the sensors to achieve various energy transduction. Ideally, many critical parameters of the optical sensing materials can be appropriately tailored to meet various specific requirements using optimal design. Over a long and cruel evolution, nature's creatures have created a variety of photonic structures. One impressive example is the iridescent wings of butterfly. The natural photonic crystals on its surfaces have inspired diverse novel designs of optical functional sensing materials, especially in the past three years. Herein, this review mainly discusses recent advances of the burgeoning butterfly‐inspired sensing materials with optical properties that can be modulated in response to different external stimuli. First, their optical sensing performance to infrared radiation/thermal, vapor, liquid, pH, and so on are discussed in details. Then, the fabrication methods and their working mechanisms are also introduced. Furthermore, the general strategies of these emerging sensing materials and their potential applications are also discussed in‐depth as well as their limitations and the future challenges. [ABSTRACT FROM AUTHOR]

Grasping and manipulation are fundamental ways for many creatures to interact with their environments. Different morphologies and grasping methods of "grippers" are highly evolved to adapt to harsh survival conditions. For example, human hands and bird feet are composed of rigid frames and soft joints. Compared with human hands, some plants like Drosera do not have rigid frames, so they can bend at arbitrary points of the body to capture their prey. Furthermore, many muscular hydrostat animals and plant tendrils can implement more complex twisting motions in 3D space. Recently, inspired by the flexible grasping methods present in nature, increasingly more bio‐inspired soft grippers have been fabricated with compliant and soft materials. Based on this, the present review focuses on the recent research progress of bio‐inspired soft grippers based on impactive gripping. According to their types of movement and a classification model inspired by biological "grippers", soft grippers are classified into three types, namely, non‐continuum bending‐type grippers, continuum bending‐type grippers, and continuum twisting‐type grippers. An exhaustive and updated analysis of each type of gripper is provided. Moreover, this review offers an overview of the different stiffness‐controllable strategies developed in recent years. [ABSTRACT FROM AUTHOR]

High‐performance flexible pressure sensors have garnered widespread applications across numerous vital fields, encompassing flexible robotics, artificial intelligence, and brain‐computer interfaces. However, the small compressibility range of flexible materials and the easy saturation characteristics of microstructures greatly limit their practical applications. Therefore, achieving high sensitivity over an extensive pressure range remains a challenge. Here, inspired by the skin, a raised structure with graded features is designed as the sensitive layer. A flexible pressure sensor with high performance is manufactured by combining iontronic interfaces. The results indicate that this sensor can stably maintain a high sensitivity of 161.26 kPa−1 even at a pressure of 320 kPa. Moreover, this sensor also has a fast response time and recovery time of 26 and 85 ms, respectively. As a demonstration, these sensors are applied to materials stiffness recognition, human motion monitoring, and control of long‐distance four‐wheel vehicles. This work will offer valuable insights and serve as a useful reference for achieving high sensitivity and a broadened sensing range in sensors. [ABSTRACT FROM AUTHOR]

Proton Exchange Membrane Fuel Cells (PEMFC) consist of channels that require efficient drainage for optimum performance. However, it remains a grand challenge to achieve both directed and high‐speed active drainage in PEMFC channels. This greatly limits current PEMFC performance. Herein, inspired by respiratory cilia, a bioinspired structural design strategy is introduced into the channel surface to significantly enhance its active droplet transport efficiency. Two artificial cilia arrays are fabricated and named as plane‐bottom artificial cilia array (PACA) and concave‐bottom artificial cilia array (CACA) according to their respective shapes. PACA demonstrates stable directional transport. The droplet speed reaches as high as 86 mm s−1 with droplet volumes ranging from 10 to 20 µL. This is surpassed by CACA. Its speed reaches as high as 163 mm s−1 for droplet volumes ranging from 10 to 50 µL. PEMFC experimental evaluation of diameter sizes shows that CACA can be tuned for enhancing its electrochemical performance. CACA‐8 achieves the maximum power density (0.5339 W cm−2) at 1.1864 A cm−2, representing an 18.70% increase compared to conventional PEMFC channels. This work provides a promising strategy for the stable and efficient transport of liquid water in PEMFC. [ABSTRACT FROM AUTHOR]

In the field of engineering, a crack, inducing enormous mechanical energy concentration at a tip, is considered a typical kind of defect. However, it is found that, to maximize the sensitivity of slit‐based mechanoreceptors, the near‐tip stress field of "risky" crack‐shaped slits is ingeniously used by scorpions to precisely detect the cyclic loads acting on walking legs without the crack nucleation from the flaw‐like tip. As a sophisticated biological mechanoelectrical transducing microsystem, the mechanoreceptor can effectively collect mechanical energy contained in the mechanical signal through antifracture slit allays and then convert the mechanical energy into electrical energy through mechanosensory neuron. The highly efficient mechanoelectrical energy conversion mechanism is theoretically analyzed and experimentally verified in a bioinspired artificial mechanoreceptor. The results demonstrate the potential of basic "design" principles, underlying the slit‐dependent mechanoreceptor, for maximizing the electromechanical conversion efficiency of the industrial mechanoelectrical transducing microsystem such as nanogenerators, ultrasensitive mechanical sensors, self‐powered portable, and wearable electronics. [ABSTRACT FROM AUTHOR]

Although diversified biological structures have evolved fog collection abilities, the typical speeds of the condensed water droplets on these surfaces are too slow to have practical utility. The main challenge focuses on the elimination of the interfacial hydrodynamic resistance without external energy support. Here, an unusual strategy for superfast self‐support transfer condensed droplets is supported by sliding on seta of desert scorpion. It can be rapidly wetted by the fog droplets owing to its conical shape with linear gradient channels. A loss of interfacial resistance by this hydrodynamically lubricating water membrane could significantly accelerate the movement of the droplets, thus making its velocity increasing by one order of magnitude, or even more. Inspired by this novel strategy, the novel bioinspired materials are fabricated with the similar gradient channel structures and droplet transportation mode, which can make the condensed droplets spontaneously slide on the low‐friction liquid membrane. The fundamental understanding of superfast fog capture and the sliding dynamics of condensed droplets in this system could inspire to develop novel materials or various systems to transfer liquid fast and efficiently without external energy support. An unusual strategy for superfast transferring condensed droplets by sliding on liquid membrane of desert scorpion seta is reported. A loss of interfacial resistance could significantly accelerate the droplets by this hydrodynamically lubricating liquid membrane. Then, the bioinspired materials with similar droplet transportation mode are fabricated, which will inspire to develop novel materials to transport liquid without external energy. [ABSTRACT FROM AUTHOR]