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The harsh working environments of proton exchange membrane fuel cells (PEMFCs) pose huge challenges to the stability of Pt‐based alloy catalysts. The widespread presence of metallic bonds with significantly delocalized electron distribution often lead to component segregation and rapid performance decay. Here we report L10−Pt2CuGa intermetallic nanoparticles with a unique covalent atomic interaction between Pt−Ga as high‐performance PEMFC cathode catalysts. The L10−Pt2CuGa/C catalyst shows superb oxygen reduction reaction (ORR) activity and stability in fuel cell cathode (mass activity=0.57 A mgPt−1 at 0.9 V, peak power density=2.60/1.24 W cm−2 in H2‐O2/air, 28 mV voltage loss at 0.8 A cm−2 after 30 000 cycles). Theoretical calculations reveal the optimized adsorption of oxygen intermediates via the formed biaxial strain on L10−Pt2CuGa surface, and the durability enhancement stems from the stronger Pt−M bonds than those in L11−PtCu resulted from Pt−Ga covalent interactions. [ABSTRACT FROM AUTHOR]

Directly splitting seawater to produce hydrogen provides a promising pathway for energy and environmental sustainability. However, current seawater splitting faces many challenges because of the sluggish kinetics, the presence of impurities, membrane contamination, and the competitive chloride oxidation reaction at the anode, which makes it more difficult than freshwater splitting. This Review firstly introduces the basic mechanisms of the anode and cathode reactions during seawater splitting. We critically analyze the primary principles for designing catalysts for seawater splitting in terms of both the hydrogen and oxygen evolution reactions, including with noble metal, noble metal free, and metal‐free catalysts. Strategies to design effective catalysts, such as active site population, synergistic effect regulation, and surface engineering, are discussed. Furthermore, promises, perspectives, and challenges in developing seawater splitting technologies for clean hydrogen generation are summarized. [ABSTRACT FROM AUTHOR]

Although Pd is a potential substitution of Pt‐based catalysts for the hydrogen evolution reaction (HER) and oxygen reduction reaction (ORR), the binding of *H and oxygenated (*O, *OOH, *OH) intermediates on Pd are stronger than on Pt, leading to its inferior activity for HER and ORR. In this work, CuPd/Pd core/shell nanoparticles with an ultrathin Pd shell (0.5 nm) are developed, which demonstrate the Pt‐like bifunctional activity for HER and ORR in acid electrolytes. The overpotential at 350 mA cm−2 for HER and the half‐wave potential for ORR on the optimal CuPd/Pd core/shell NPs are 76 mV and 0.854 V versus reversible hydrogen electrode (RHE), respectively, which are comparable to that of Pt and among the best of the reported Pd‐based catalysts. Density functional theory calculations indicate that the significantly enhanced HER/ORR activity on CuPd/Pd core/shell NPs with 0.5 nm Pd shell stem from the compressive strain induced downshift of d‐band center for Pd (by 2.0%), which weakens the binding strength of *H and oxygenated intermediates and promotes the reaction kinetics. [ABSTRACT FROM AUTHOR]

O ‐ H ‐ Erlebnis: Das erste isomerenreine mehrfach hydroxylierte Fulleren, C60(OH)8, lässt sich in wässriger Lösung oxidieren und reduzieren. Ein elektrochemisch auf einer Glaskohlenstoffelektrode (GCE) abgeschiedenes C60(OH)8 ‐ Salz ist ein überraschend aktiver übergangsmetallfreier Katalysator der Wasserstoffentwicklung. [ABSTRACT FROM AUTHOR]