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Abstract Development of high‐performance, low‐cost catalysts for electrochemical water splitting is key to sustainable hydrogen production. Herein, ultrafast synthesis of carbon‐supported ruthenium–copper (RuCu/C) nanocomposites is reported by magnetic induction heating, where the rapid Joule's heating of RuCl₃and CuCl₂at 200 A for 10 s produces Ru–Cl residues‐decorated Ru nanocrystals dispersed on a CuCl_xscaffold, featuring effective Ru to Cu charge transfer. Among the series, the RuCu/C‐3 sample exhibits the best activity in 1 mKOH toward both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), with an overpotential of only −23 and +270 mV to reach 10 mA cm⁻², respectively. When RuCu/C‐3 is used as bifunctional catalysts for electrochemical water splitting, a low cell voltage of 1.53 V is needed to produce 10 mA cm⁻², markedly better than that with a mixture of commercial Pt/C+RuO₂(1.59 V). In situ X‐ray absorption spectroscopy measurements show that the bifunctional activity is due to reduction of the Ru–Cl residues at low electrode potentials that enriches metallic Ru and oxidation at high electrode potentials that facilitates the formation of amorphous RuO_x. These findings highlight the unique potential of MIH in the ultrafast synthesis of high‐performance catalysts for electrochemical water splitting. 

Carbon-based functional nanocomposites have emerged as potent antimicrobial agents and can be exploited as a viable option to overcome antibiotic resistance of bacterial strains. In the present study, graphitic carbon nitride nanosheets are prepared by controlled calcination of urea. Spectroscopic measurements show that the nanosheets consist of abundant carbonyl groups and exhibit apparent photocatalytic activity under UV photoirradiation towards the selective production of singlet oxygen. Therefore, the nanosheets can effectively damage the bacterial cell membranes and inhibit the growth of bacterial cells, such as Gram-negative Escherichia coli, as confirmed in photodynamic, fluorescence microscopy, and scanning electron microscopy measurements. The results from this research highlight the unique potential of carbon nitride derivatives as potent antimicrobial agents. 

Abstract Antibiotic‐resistant bacterial strains are an ever‐present hurdle for human health. A route to overcoming this threat is the development of effective antimicrobial agents based on carbon‐supported nanocomposites. In this study, carbon dots (CD) are synthesized by a facile hydrothermal treatment of ethylenediaminetetraacetic acid and melamine and further functionalized with nickel hydroxide colloids. Whereas CD alone exhibits virtually no antimicrobial activity under photoirradiation at 365 nm againstEscherichia coliin comparison to the blank control, the performance is markedly enhanced with the Ni(OH)₂‐CD nanocomposites, with the lag time prolonged from 7 to 15 h and growth rate reduced by ca. 15%. This is ascribed to the Ni(OH)₂colloids that facilitate the separation of photogenerated electron‐hole pairs and ensuing production of superoxide radicals, as confirmed by photoluminescence and electron paramagnetic resonance measurements, which induce oxidative stress and damage to the bacterial cell membranes, thereby leading to effective bactericidal activity. Consistent results are obtained in live/dead assays. Results from this work highlight the unique potential of carbon‐based composites in the development of next‐generation antimicrobial agents. 

Ruthenium has emerged as a promising substitute for platinum toward the hydrogen evolution/oxidation reaction (HER/HOR). Herein, ruthenium/carbon composites are prepared by magnetic induction heating (300 A, 10 s) of RuCl₃, RuBr₃or RuI₃loaded on hollow N‐doped carbon cages (HNC). The HNC‐RuCl₃‐300A sample consists of Ru nanoparticles (dia. 1.96 nm) and abundant Cl residues. HNC‐RuBr₃‐300A possesses a larger nanoparticle size (≈19.36 nm) and lower content of Br residues. HNC‐RuI₃‐300A contains only bulk‐like Ru agglomerates with a minimal amount of I residues, due to reduced Ru‐halide bonding interactions. Among these, HNC‐RuCl₃‐300A exhibits the best HER activity in alkaline media, with a low overpotential of only −26 mV to reach 10 mA cm⁻², even outperforming Pt/C, and can be used as the cathode catalyst for anion exchange membrane water electrolyzer (along with commercial RuO₂as the anode catalyst), producing 0.5 A cm⁻²at 1.88 V for up to 100 h, a performance markedly better than that with Pt/C. HNC‐RuCl₃‐300A also exhibits the best HOR activity, with a half‐wave potential (+18 mV) even lower than that of Pt/C (+35 mV). These activities are ascribed to the combined contributions of small Ru nanoparticles and Ru‐to‐halide charge transfer that weaken H adsorption.