In recent years, real-time health management has been received increasing attention, benefiting from the rapid development of flexible and wearable devices. Conventionally, flexible and wearable devices were used in collecting...

Electrophysiological monitoring under strenuous exercise by using stretchable dry electrodes is vital for healthcare monitoring, prosthetic control, human−machine interfaces and other biomedical applications. However, the existing dry electrodes are not applicable to the strenuous exercise situation that always involves both fast moving and profuse sweating. Herein, we present a nano-thick porous stretchable dry electrode system with high stretchability and water permeability. The system attaches conformably to the skin and stretches with it under Van der Waals forces even at sweating conditions, allowing the detection of electromyogram when moving with an acceleration of 10 g at a sweating rate of 2.8 mg cm−2 min−1. It is also capable of acquiring electrocardiogram and electroencephalogram signals. The strategy proposed would enable the biomedical studies and related applications with the requirement of stably recording electrophysiological signals under strenuous exercise scenarios.

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Atomically ordered intermetallic compounds (OICs) have aroused remarkable interests for wide applications and are considered as very promising materials for electrocatalysis owing to the strict stoichiometry, well-defined atom binding environment, and the specific crystalline phase. However, the tunable synthesis of the intermetallics remains a giant challenge. Herein, this study reports the preparation of the Pd-Sn OICs composed of an interconnected nanowire network structure with adjustable molar ratios of elements Pd and Sn. The co-reduction of Pd(acac) 2 and SnCl 2 •2H 2 O in ethylene glycol (EG) in the presence of sodium hypophosphite (NaH 2 PO 2 ) as the reducing agent affords OICs of three phases: hexagonal Pd 3 Sn 2 -P6 3 /mmc, orthorhombic PdSn-Pnmb, and orthorhombic PdSn 2 -Aba2. Also, the pure phase can convert to two mixed phases (Pd 3 Sn 2 /PdSn and PdSn/PdSn 2 ) by just altering the feed ratio. It is found that orthorhombic PdSn-Pnmb OIC has a large electrochemically active surface area (ECSA), excellent electrocatalytic performance (4857 mA mg Pd −1), and outstanding stability toward ethanol oxidation reaction (EOR), which could be attributed to its optimal electronic structure. These results demonstrate that the phase engineering of OICs with desired components is an excellent way for catalysts design.