The electrochemical discharge performance of the Mg–Al–Pb–Ce–Y alloy in 3.5 wt% NaCl solution is investigated by using electrochemical techniques and compared with that of pure magnesium, AZ31, and Mg–Al–Pb alloys.

3D printing of graphene electrodes with high mechanical strength has been a growing interest in the development of advanced energy, environment, and electronic systems, yet is extremely challenging. Herein, a 3D printed bioinspired electrode of graphene reinforced with 1D carbon nanotubes (CNTs) (3DP GC) with both high flexural strength and hierarchical porous structure is reported via a 3D printing strategy. Mechanics modeling reveals the critical role of the 1D CNTs in the enhanced flexural strength by increasing the friction and adhesion between the 2D graphene nanosheets. The 3DP GC electrodes hold distinct advantages: i) an intrinsically high flexural strength that enables their large‐scale applications; and ii) a hierarchical porous structure that offers large surface area and interconnected channels, endowing fast mass and/or charge and ions transport rate, which is thus beneficial for acting as an ideal catalyst carrier. The 3DP GC electrode integrated with a NiFeP nanosheets array exhibits a voltage of 1.58 V at 30 mA cm−2 as bifunctional electrode for water splitting, which is much better than most of the reported Ni‐, Co‐, and Fe‐based bifunctional electrocatalysts. Importantly, this study paves the way for the practical applications of 3D printed graphene electrodes in many energy conversion/storage, environmental, and electronic systems where high flexural strength is preferred.

Limb motion capture is essential in human motion-recognition, motor-function assessment and dexterous human-robot interaction for assistive robots. Due to highly dynamic nature of limb activities, conventional inertial methods of limb motion capture suffer from serious drift and instability problems. Here, a motion capture method with integral-free velocity detection is proposed and a wearable device is developed by incorporating micro tri-axis flow sensors with micro tri-axis inertial sensors. The device allows accurate measurement of three-dimensional motion velocity, acceleration, and attitude angle of human limbs in daily activities, strenuous, and prolonged exercises. Additionally, we verify an intra-limb coordination relationship exists between thigh and shank in human walking and running, and establish a neural network model for it. Using the intra-limb coordination model, dynamic motion capture of human lower limbs including thigh and shank is tactfully implemented by a single shank-worn device, which simplifies the capture device and reduces cost. Experiments in strenuous activities and long-time running validate excellent performance and robustness of the wearable device in dynamic motion recognition and reconstruction of human limbs.

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Electrochemical nitrogen reduction reaction (NRR) provides a facile and sustainable strategy to produce ammonia (NH 3) at ambient conditions. However, the low NH 3 yield and Faradaic efficiency (FE) are still the main challenges due to the competitive hydrogen evolution reaction (HER). Herein, a three-phase electrocatalyst through in situ fabrication of Au nanoparticles (NPs) located on hydrophobic carbon fiber paper (Au/o-CFP) is designed. The hydrophobic CFP surface facilitates efficient three-phase contact points (TPCPs) for N 2 (gas), electrolyte (liquid), and Au NPs (solid). Thus, concentrated N 2 molecules can contact the electrocatalyst surface directly, inhibiting the HER since the lowered proton concentration and overall enhancing NRR. The three-phase Au/o-CFP electrocatalyst presents an excellent NRR performance with high NH 3 yield rate of 40.6 µg h −1 mg −1 at −0.30 V and great FE of 31.3% at −0.10 V versus RHE (0.1 m Na 2 SO 4). The N 2-bubble contact angle result and cyclic voltammetry analysis confirm that the hydrophobic interface has a relatively strong interaction with N 2 bubble for enhanced NRR and weak electrocatalytic activity for HER. Significantly, the three-phase Au/o-CFP exhibits excellent stability with a negligible fluctuation of NH 3 yield and FE in seven-cycle test. This work provides a new strategy for improving NRR and simultaneously inhibiting HER.

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