In hydrogen production, the anodic oxygen evolution reaction (OER) limits the energy conversion efficiency and also impacts stability in proton-exchange membrane water electrolyzers. Widely used Ir-based catalysts suffer from insufficient activity, while more active Ru-based catalysts tend to dissolve under OER conditions. This has been associated with the participation of lattice oxygen (lattice oxygen oxidation mechanism (LOM)), which may lead to the collapse of the crystal structure and accelerate the leaching of active Ru species, leading to low operating stability. Here we develop Sr–Ru–Ir ternary oxide electrocatalysts that achieve high OER activity and stability in acidic electrolyte. The catalysts achieve an overpotential of 190 mV at 10 mA cm–2 and the overpotential remains below 225 mV following 1,500 h of operation. X-ray absorption spectroscopy and 18O isotope-labeled online mass spectroscopy studies reveal that the participation of lattice oxygen during OER was suppressed by interactions in the Ru–O–Ir local structure, offering a picture of how stability was improved. The electronic structure of active Ru sites was modulated by Sr and Ir, optimizing the binding energetics of OER oxo-intermediates.

Wearable sensing technologies have received considerable interests due to the promising use for real‐time monitoring of health conditions. The sensing part is typically made into a thin film that guarantees high flexibility with different sensing materials as functional units at different locations. However, a thin‐film sensor easily breaks during use because it cannot adapt to the soft or irregular body surfaces, and, moreover, it is not breathable or comfortable for the wearable application. Herein, a new and general strategy of making electrochemical fabric from sensing fiber units is reported. These units efficiently detect a variety of physiological signals such as glucose, Na+, K+, Ca2+, and pH. The electrochemical fabric is highly flexible and maintains structural integrity and detection ability under repeated deformations, including bending and twisting. They demonstrate the capacity to monitor health conditions of human body in real time with high efficacy.

In electrochemical energy storage and conversion systems, the anodic oxygen evolution reaction (OER) accounts for a large proportion of the energy consumption. The electrocatalytic urea oxidation reaction (UOR) is one of the promising alternatives to OER, owing to its low thermodynamic potential. However, owing to the sluggish UOR kinetics, its potential in practical use has not been unlocked. Herein, we developed a tungsten‐doped nickel catalyst (Ni‐WOx) with superior activity towards UOR. The Ni‐WOx catalyst exhibited record fast reaction kinetics (440 mA cm−2 at 1.6 V versus reversible hydrogen electrode) and a high turnover frequency of 0.11 s−1, which is 4.8 times higher than that without W dopants. In further experiments, we found that the W dopant regulated the local charge distribution of Ni atoms, leading to the formation of Ni3+ sites with superior activity and thus accelerating the interfacial catalytic reaction. Moreover, when we integrated Ni‐WOx into a CO2 flow electrolyzer, the cell voltage is reduced to 2.16 V accompanying with ≈98 % Faradaic efficiency towards carbon monoxide.

Lithium‐carbon dioxide (Li‐CO2) batteries are considered promising energy‐storage systems in extreme environments with ultra‐high CO2 concentrations, such as Mars with 96% CO2 in the atmosphere, due to their potentially high specific energy densities. However, besides having ultra‐high CO2 concentration, another vital but seemingly overlooked fact lies in that Mars is an extremely cold planet with an average temperature of approximately −60 °C. The existing Li‐CO2 batteries could work at room temperature or higher, but they will face severe performance degradation or even a complete failure once the ambient temperature falls below 0 °C. Herein, ultra‐low‐temperature Li‐CO2 batteries are demonstrated by designing 1,3‐dioxolane‐based electrolyte and iridium‐based cathode, which show both a high deep discharge capacity of 8976 mAh g−1 and a long lifespan of 150 cycles (1500 h) with a fixed 500 mAh g−1 capacity per cycle at −60 °C. The easy‐to‐decompose discharge products in small size on the cathode and the suppressed parasitic reactions both in the electrolyte and on the Li anode at low temperatures together contribute to the above high electrochemical performances.

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