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Signal transmission between rigid robots is usually realized through rigid electronic components like coil or circuit board. However, these rigid electronic units are difficult to be used in fully flexible soft robots because of the mismatch of Young's modulus. Liquid metal (LM), as a flexible fluid with superior electric conductivity, can be served as the alternative material for rigid electronic units to realize signal transmission in fully flexible soft robots. Herein, a fully flexible soft robot is fabricated, which is mainly consists of two functional units: the soft tentacle integrated with liquid metal spiral wire and the body prepared by Nd2Fe14B magnetic powders/Ecoflex composites. The fully flexible soft robot can not only transmit electric signals based on electromagnetic induction but also be actuated by an external magnetic field to form diverse signal transmission pathways. Related mechanisms of transmitting electric signal and driving are studied by Maxwell numerical simulation. Driven by an external magnetic field, three soft robots are capable to constitute two different pathways to transmit electric signals to the oscilloscope. It is believed that the integration of LM into the magnetic composites provides an open perspective to realize the signal transmission in fully flexible soft robot and favors the development of multifunctional soft robot. [ABSTRACT FROM AUTHOR]

Abstract The MgO-loaded SiO 2 nanocomposites were successfully synthesized via a facile precipitation and calcination method, and used for the elimination of antibiotics from aqueous solution. Multiple techniques such as X-ray photoelectron spectroscopy (XPS), fourier transform infrared (FT-IR), transmission electron microscope (TEM), X-ray diffraction (XRD) and Brunauer-Emmett-Teller (BET) were employed to characterize the structure and morphology of the obtained nanocomposites. The effects of the loading content of MgO, initial solution pH and temperature on the adsorption performance of MgO-loaded SiO 2 nanocomposites were assessed by removing tetracycline from aqueous solution. It was found that 50% MgO-loaded SiO 2 exhibited excellent adsorption performance towards tetracycline with a removal rate above 80% in a wide pH range of 4–10, which was much higher than that of individual MgO and mesoporous SiO 2. The nanocomposite possessed higher specific surface area (356.02 m2 g−1) and smaller MgO particles compared with pure MgO (81.02 m2 g−1), which can provide more active sites, thus enhancing the adsorption performance towards tetracycline. The electrostatic interaction and inner-sphere complexation between nanocomposites and tetracycline molecules were considered to play important roles in the adsorption process of tetracycline. The as-synthesized nanocomposites as promising adsorbents have a potential application in the removal of antibiotics from aqueous solution. Graphical abstract Unlabelled Image Highlights • MgO-loaded SiO 2 nanocomposite was prepared by a precipitation-calcination process. • The nanocomposite exhibited high specific surface area of 356.02 m2 g−1. • Small-sized MgO particles were embedded into the mesopores of SiO 2. • The nanocomposite showed excellent adsorption performance towards tetracycline. • The nanocomposite maintained a high adsorption capacity in a pH range of 4–10. [ABSTRACT FROM AUTHOR]

• MgNCN/MgO nanocomposites were firstly prepared by a one-pot calcination method. • MgNCN/MgO nanocomposites were firstly used as H 2 O 2 activator for TC degradation. • The catalytic degradation of TC could be conducted in a wide pH range of 4-10. • Singlet oxygen was main reactive oxygen species responding for TC degradation. • The Mg-N coordination in composites played a key role in H 2 O 2 activation. Currently existing Fenton-like catalysts were limited in wastewater treatment owing to their potential transition-metal poisoning, narrow applicable pH range and high dependence on external energy excitation. In this work, the MgNCN/MgO nanocomposites were firstly synthesized by a facile one-pot calcination of melamine and basic magnesium carbonate, and used as novel H 2 O 2 activator for antibiotic removal. It was found that the MgNCN/MgO composite calcined at 550°C with the mass ratio of melamine to basic magnesium carbonate at 2:1, exhibited an excellent catalytic ability to tetracycline (TC) degradation in a wide pH range of 4-10 without any external energy input. More than 90% of TC (100 mL, 50 mg/L) could be degraded within 30 min by 10 mg of the nanocomposite in the presence of 0.2 mL of 30 wt% H 2 O 2. Based on the experimental results, it was concluded that the Mg-N coordination between MgNCN and MgO in MgNCN/MgO nanocomposites activated H 2 O 2 to produce primary singlet oxygen (1O 2) and minor hydroxyl radicals (·OH), responding for TC degradation. In addition, the degradation pathways of TC were deduced by determining the generated intermediates during the degradation process. This work provided a novel idea for designing transition-metal-free catalysts for nonradical activation of H 2 O 2 in the absence of external energy excitation. [Display omitted] [ABSTRACT FROM AUTHOR]

• MgO2 rod, cube and flower were prepared from the isomorphic MgO precursors. • The hydrated MgO intermediate (MgOH+) was easily oxidized into MgO2 by H2O2. • Flower-like MgO could be completely converted into MgO2 in a short time. • MgO precursors acted as self-templates for in-situ growth of MgO2. • MgO2 rod exhibited excellent performance for MB degradation. Magnesium peroxide (MgO 2) has been widely used in the field of environmental remediation including organics degradation and bacterial inactivation, due to its good stability, environmental friendliness and high active oxygen content. In this work, MgO 2 rod, cube and flower were synthesized firstly by the reaction of isomorphic MgO and H 2 O 2 , and used as Fenton-like oxidants for methylene blue (MB) degradation. The structure and morphology of as-prepared products were characterized by XRD, SEM and TEM techniques. It was found that the synthesized MgO 2 retained the original morphologies of MgO precursors. The MgO precursors firstly interacted with H 2 O to produce hydrated MgO intermediate (MgOH+), which was further oxidized into MgO 2 by H 2 O 2. The flower-like MgO could be completely converted into MgO 2 phase in a relatively short time, due to the porous structure assembled by thin nanosheets. Besides, the MgO precursors also served as self-templates for in-situ growth of MgO 2 , allowing the MgO 2 products to maintain the morphological characteristics of MgO precursors. The results of degradation experiments showed that MgO 2 rod exhibited better performance for MB degradation than MgO 2 cube and flower, owing to its unique structure and high active oxygen content. [ABSTRACT FROM AUTHOR]

• 3D flower-like MgO 2 was synthesized via a facile one-step precipitation process. • SO 4 2− played a vital role in the formation of flower-like MgO 2 nanostructures. • 10 mg of flower-like MgO 2 could degrade 90 % of TC (100 mL, 50 mg/L) within 1 h. • The column containing 3D MgO 2 could quickly eliminate TC for consecutive runs. • OH was confirmed to be the main active species responsible for TC degradation. Hierarchically three dimensional (3D) flower-like magnesium peroxide (MgO 2) nanostructures were synthesized through a facile one-step precipitation method. The effects of magnesium salt, reaction temperature, precipitant and surfactant on the morphology and structure of MgO 2 were systematically investigated. The as-obtained samples using magnesium sulfate, ammonia and trisodium citrate were composed of 3D flowers assembled by numerous nanosheets, and SO 4 2− played a vital role in the formation of flower-like nanostructures. The 3D flower-like MgO 2 possessed high active oxygen content of 24.10 wt% and large specific surface area of 385 m2/g. Ten mg of flower-like MgO 2 could efficiently degrade 90 % of tetracycline (TC) within 60 min under stirring condition. ESR tests and radical quenching experiments suggested that hydroxyl radicals were crucial for TC degradation. Moreover, the column filled with flower-like MgO 2 could quickly and efficiently eliminate TC with the assistance of air flow, and the degradation efficiency almost had no decrease even after twenty consecutive runs. Significantly, the concentrations of magnesium and iron ions dissolved in the filtrate from the column were far below the limits of drinking water standards. Additionally, the possible degradation pathways of TC were also proposed according to the determination of generated intermediates during the degradation process. [ABSTRACT FROM AUTHOR]

• Cu 2 O/Cu 2 S nanocomposite was obtained by a co-precipitation and calcination method. • The decoration of Cu 2 S enhanced the adsorption and photocatalytic performances. • The recombination of photogenerated electrons and holes was suppressed effectively. • O 2 − and h + were crucial for the photocatalytic degradation of organic pollutants. The Cu 2 S-decorated Cu 2 O nanocomposites were synthesized by a facile co-precipitation and calcination method, and used as adsorbent and photocatalyst to remove organic pollutants from wastewater. Batch adsorption experiments were conducted to investigate the influences of molar ratio of Cu 2 O to Cu 2 S, initial solution pH, coexisting anion and temperature on the adsorption performances. As-obtained Cu 2 O/Cu 2 S-9/1 nanocomposite with high specific surface area (45.88 m2/g) exhibited superior adsorption ability towards Congo red, methyl orange and tetracycline in aqueous solution. The adsorption of organics onto the nanocomposite was a spontaneous and exothermic process, and the adsorption processes could be well described by the Freundlich isothermic and Pseudo-second-order kinetic models. The Cu 2 O/Cu 2 S-9/1 nanocomposite also showed excellent photocatalytic degradation activities for organic pollutants. Optical properties characterization suggested that the decoration of Cu 2 S could effectively enhance visible-light absorption and inhibit the recombination of photo-generated electron-hole pairs. ESR tests and trapping experiments of reactive species indicated that both superoxide radicals (O 2 −) and holes (h +) were crucial for the photocatalytic degradation of organic pollutants. Moreover, the photocatalytic efficiency of Cu 2 O/Cu 2 S-9/1 nanocomposite had no significant decrease even after four consecutive runs. The bifunctional nanocomposite as adsorbent and photocatalyst presents a great potential in treating organic-contaminated wastewater. [ABSTRACT FROM AUTHOR]

Manufacturing abrasion‐resistant superhydrophobic matters is challenging due to the fragile feature of the introduced micro‐/nanoscale surface roughness. Besides the long‐term durability, large scale at meter level, and 3D complex structures are of great importance for the superhydrophobic objects used across diverse industries. Here it is shown that abrasion‐resistant, half‐a‐meter scaled superhydrophobic objects can be one‐step realized by the selective laser sintering (SLS) 3D printing technology using hydrophobic‐fumed‐silica (HFS)/polymer composite grains. The HFS grains serve as the hydrophobic guests while the sintered polymeric network provides the mechanical strength, leading to low‐adhesion, intrinsic superhydrophobic objects with desired 3D structures. It is found that as‐printed structures remained anti‐wetting capabilities even after undergoing different abrasion tests, including knife cutting test, rude file grinding test, 1000 cycles of sandpaper friction test, tape test and quicksand impacting test, illustrating their abrasion‐resistant superhydrophobic stability. This strategy is applied to manufacture a shell of the unmanned aerial vehicle and an abrasion‐resistant superhydrophobic shoe, showing the industrial customization of large‐scale superhydrophobic objects. The findings thus provide insight for designing intrinsic superhydrophobic objects via the SLS 3D printing strategy that might find use in drag‐reduce, anti‐fouling, or other industrial fields in harsh operating environments. [ABSTRACT FROM AUTHOR]

Electromagnetism, which has been used to harvest energy from human motion, is expected to power an increasing number of wearable electronic devices upon fabrics. However, most reported electromagnetism‐based approaches necessitate rigid and heavy setups. Here, a scalable‐manufactured flexible magnetoelectrical clothing generator is demonstrated that can generate electricity through the swinging of the arms. A "particle flow spinning" (PFS) method can produce continuous magnetic yarns, resulting in a magnetic fabric through an industrial weaving machine. Fabrics can be prepared in large quantities and have a lower cost. The magnetic fabrics and conductive wires are built on two sides of the armpit parts of the clothing, leading to continuous and stable voltage and current when swinging arm, 14.3 V peak voltage, 31.2 mA peak current, and 96 mW peak power (3197 mW m−2 peak power density) in series to a low‐impedance load (750 ohms). Furthermore, the magnetic fabrics can work under water without sealing treatment, in acidic/alkaline environments or at extreme temperatures. The magnetoelectrical clothing generator can power diverse electronic devices in many fields, such as LED lights, calculators, wireless communication, and health monitoring devices. This approach opens a path toward exploring electromagnetic energy harvesting strategies to realize power generation for the development of clothing electronics. [ABSTRACT FROM AUTHOR]

• A wireless and battery-free sensing system (RWBS) has been built. • The RWBS can be used for monitoring human spine/joint motions in vivo. • Reliable RWBS can function in vivo even after being broken into pieces. Continuous monitoring of spinal and joint motions in patients allows surgeons to optimize patient rehabilitation. However, the current monitoring approaches are achieved via tethered devices, which are inconvenient and associated with a risk of infections. In this study, we developed and validated a new type of reliable wireless, battery-free, and implantable sensing system (RWBS) for the real-time monitoring of physiological bending of spines and joints. The RWBS exploits the unique movement-sensing capabilities of an implantable flexible magnetic strip, the signals from which are detected with an external receiver. We implanted this magnetic strip beneath the skins of Sprague Dawley rats and human cadavers and demonstrated that in combination with the receiver, the magnetic strip enabled real-time in vivo and wireless monitoring of motions in both rats (anesthetized/awake) and human cadavers. The adaptability of RWBS in other human bones has been verified by sensing the motions of elbow joints and knee joints. The simple design of the RWBS allowed it to continue functioning in vivo after the magnetic strip had been broken into two or more pieces, indicating its high reliability. Thus, the RWBS is biocompatible, exhibits excellent functionalities, and can be conveniently implemented in both rats and humans. This device will help to facilitate the post-surgery monitoring of spinal and joint movements of human patients. [ABSTRACT FROM AUTHOR]

Microstructural evolution during multi-pass friction stir processing (FSP) of the as-cast ZrB 2 /6061Al nanocomposite and corresponding mechanical properties were investigated. The initial sample was characterized by primarily micrometer-sized clusters of ZrB 2 nanoparticles within the coarse dendrites. Multi-pass FSP successively broke these clusters, refined the matrix grains and finally produced a thoroughly homogeneous microstructure in the stirred zone (except for the upper layer). The process of cluster redistribution was found to be governed by material flow around the pin, wherein the actual stir or mixing driven particle dispersion only occurred in the thread grooves. Meanwhile, the pinning effect of ZrB 2 nanodispersoids retarded grain growth following recrystallization and led to a further reduction in grain size. On the other hand, compared with the initial state, both the microhardness and tensile strengths of the FSPed composites were gradually enhanced with consecutive passes. These increases can be attributed to the combination effect of grain refinement and dislocation strengthening induced by uniform distribution of ZrB 2 nanoparticles. Quantitative analysis in the 4-pass FSPed composite indicated that Orowan strengthening contributed the most to the yield strength. [ABSTRACT FROM AUTHOR]

• Three kinds of functional inks for printing magnetoelectric sensor parts were prepared. • Human-computer interaction functions in extreme environments beyond atmosphere. • The sensing glove was printed by a multi-material integrated manipulator. • Sensing gloves adopted self-powered sensing strategy. Current Human-Computer Interaction (HCI) devices allow interactive communications between the users' gestures and the computers. However, extreme environments beyond atmosphere, such as underwater or smoke, will greatly interrupt the normal operation of existing HCI devices. Here we demonstrated the fabrication of 3D-printed self-powered sensing gloves that can be used for underwater/smoke environmental HCI. A home-made multi-extrusion-head manipulator, which can simultaneously print three kinds of functional inks including magnetic, conductive and elastic materials, has been developed to generate the self-powered sensing gloves. The magnetic part was printed on the polymeric thumb region while four liquid metal coils were printed on the other four fingers, yielding the self-powered gesture recognition by clicking the fingers or nine-key input method keys of alphabetic typing. Our work offers a design of self-powered sensing glove for gesture recognition and therefore provides a pathway to realize HCI in extreme environments. [ABSTRACT FROM AUTHOR]

Biomechanical energy harvesting, extreme environments, flexible fabrics, flexible yarns, magnetoelectrical clothing generators Magnetoelectrical Clothing Generator for High-Performance Transduction from Biomechanical Energy to Electricity (Adv. Funct. Keywords: biomechanical energy harvesting; extreme environments; flexible fabrics, flexible yarns; magnetoelectrical clothing generators EN biomechanical energy harvesting extreme environments flexible fabrics, flexible yarns magnetoelectrical clothing generators 1 1 1 02/04/22 20220202 NES 220202 B Magnetoelectrical Clothing Generator b In article number 2107682, Weilin Xu, Xiaoming Tao, Guangming Tao, Bin Su, and co-workers show scalable-manufactured flexible magnetoelectrical clothing that can convert mechanical energy generated by daily behavior into electrical energy required for electronic devices, solving the problem of continuous power supply of electronic clothing especially in harsh outdoor environments, and promoting sustainable development in wearable electronics. [Extracted from the article]

Shape deformation is a survival wisdom that many animals have evolved to protect themselves and prey foods easier. Soft magnetic composites provided an untethered strategy to allow the soft robots deform and move. However, it is great challenges for magnetic soft robots to squeeze in constrained environment, such as slits smaller than their sizes, as well as carry and release desired items. Here we demonstrate a magnetic hollow soft robot (MHSR) composed of soft NdFeB/Ecoflex composites, which has a considerable magnetostimulated shrinkability. The MHSR can squeeze through slits one fifth of its height and channels half of its height without structural damage. Notably, the MHSR can carry about twenty pellets to squeeze through a slit only half of its height, and then actively release them. Our design for deformable magnetic soft robots to squeeze through small slits or channels have laid a foundation for the development of soft robots to actively adapt to the constrained environment. [Display omitted] • Soft robot (MHSR) with considerable magnetostimulated shrinkability is reported. • The MHSR can squeeze through slits one fifth of its height. • The MHSR can carry twenty pellets through a slit and then actively release them. • This study will promote the development of soft robots in constrained environment. [ABSTRACT FROM AUTHOR]

Sensing and shape-deforming are survival wisdoms that many creatures have evolved to perceive their surrounding information and protect themselves against the changes of surrounding environments. Endowing soft robots with integrated sensing and shape-deforming capabilities is critical to the development of smart soft robots, however, has not been attempted. Magnetic composites consist of soft elastomer and magnetic powders are opening up a revolutionary avenue in the fields of soft robots. Here we report a smart soft robot developed with magnetic NdFeB/Ecoflex composites that can sense and then deform under the water inspired by the sea anemone. The soft robot is composed of two parts: top soft sensing tentacles and a bottom magnetostimulated shrinkable body. When the surrounding water flow velocity increases, the soft sensing tentacles can convert the mechanical stimuli to electric signals, informing the soft robot to deform in order to avoid being swept away. Related mechanisms have been studied by Maxwell numerical simulation and Abaqus numerical calculation. Furthermore, shrinkable performances of the robot have been optimized by tuning the geometric structure and material parameters. The promising performance characteristics of such soft magnetic composites robots open new opportunities for the development of smart robots to actively adapt to harsh environments. [ABSTRACT FROM AUTHOR]