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Traditional calcination usually causes sintering of Pt, which diminishes Pt exposure in proton exchange membrane fuel cell (PEMFC) electrodes. In the present work, a facile self‐confined method for synthesizing highly dispersed PtCo‐alloy on Co, N co‐doped mesoporous carbon (PCN‐MC) is developed via a dual‐template strategy. Owing to the co‐confined effect of Zn in the bimetallic zeolite‐based imidazolate framework (ZIF) and Mg(OH)2 template, ultra‐fine 2.7 nm PtCo‐alloy with 2–3 atomic‐layer Pt‐skin nanoparticles are obtained. By adjusting the Co/Zn feeding‐ratio in the bimetallic ZIF at 8/7, the alloying degree and nanoparticle size are optimized to achieve an outstanding oxygen reduction reaction activity with a high mass activity (MA) of 0.956 A mgPt−1 in 0.1 m HClO4, about 7.5‐fold of that of commercial Pt/C. Furthermore, notable durability is also achieved with 81% retention of the initial MA after 30k cycles conducted between 0.6–1.0 V (versus reversible hydrogen electrode). These features are also verified by a H2–Air fuel cell test with an excellent combination of mass activity, power density, and durability. This strategy provides a feasible route for the large‐scale synthesis of highly‐dispersed PtCo‐alloy catalysts.

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Hierarchical NiCo2S4 nanostructures directly supported on nickel foam show excellent electrochemical performances for supercapacitors.

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Nickel‐foam‐supported ZnxNi1−xS nanosheets are synthesized by a two‐step hydrothermal method. The ZnxNi1−xS nanosheets can be considered as the product of the partial substitution of Zn2+ ions by Ni2+ ions in the ZnS lattice. The resulting ZnxNi1−xS/Ni foam can be directly used as an electrode for supercapacitors. It can reach a specific capacitance of 1412 F g−1 at a current density of 1 Ag−1 with 68.0 % capacitance retention at 16 Ag−1. Control experiments show that the electrochemical performances of ZnxNi1−xS nanosheets are much better than those of ZnS and NiS prepared under the same conditions. Furthermore, a hybrid supercapacitor device was assembled by using the ZnxNi1−xS nanosheets as the positive electrode and porous carbon as the negative electrode; the device exhibited high power and energy densities. This study demonstrates that the construction of bimetal sulfides is a strategy to develop high‐performance supercapacitor electrode materials.

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A ruthenium–nickel alloy nanostructure exhibits a low overpotential and excellent activity stability for the hydrogen evolution reaction in 1 M KOH.