A cost-effective and efficient electrocatalyst for the oxygen evolution reaction during the electrolysis of water is highly desired. In an effort to develop an economical material for replacing precious-metal-based catalysts, a novel and self-standing amorphous ultrathin nanosheet (NS) of bimetallic iron-nickel boride (Fe-Ni-B NSs) on Ni foam is presented, which displays a better oxygen-evolving activity compared to the precious-metal catalyst RuO . In 1.0 m KOH electrolyte solution, it requires an overpotential of only 237 mV to reach a current density of 10 mA cm with a small Tafel slope of 38 mV dec and shows prominent long-term electrochemical stability. A synergistic effect between highly abundant catalytically active sites on the 3D porous substrate improved the electron transport arising from the presence of highly negative boron, and the high conductivity of the substrate results in an outstanding electrocatalytic activity. The advanced catalytic activity, facile electrode fabrication, and low costs make it a potential oxygen-evolving material, which may be extended to other energy-conversion and storage technologies.

It still remains challenging to simultaneously achieve high stability, selectivity, and activity in CO2 reduction. Herein, a dual chainmail‐bearing nickel‐based catalyst (Ni@NC@NCNT) was fabricated via a solvothermal‐evaporation‐calcination approach. In situ encapsulated N‐doped carbon layers (NCs) and nanotubes (NCNTs) gave a dual protection to the metallic core. The confined space well maintained the local alkaline pH value and suppressed hydrogen evolution. Large surface area and abundant pyridinic N and Niδ+ sites ensured high CO2 adsorption capacity and strength. Benefitting from these, it delivered a CO faradaic efficiency of 94.1 % and current density of 48.0 mA cm−2 at −0.75 and −1.10 V, respectively. Moreover, the performance remained unchanged after continuous electrolysis for 43 h, far exceeding Ni@NC with single chainmail, Ni@NC/NCNT with Ni@NC sitting on the walls of NCNT, bare NCNT and most state‐of‐the‐art catalysts, demonstrating structural superiority of Ni@NC@NCNT. This work sheds light on designing unique architectures to improve electrochemical performances.

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A single [NiII(H2O)6]2+ cation is dynamically associated with a negaitvely charged metal‐organic layer (MOL) via hydrogen bonding and coulombic interactions to serve as a catalyst for selective reduction of O2 to H2O2. The two‐electron reduction of oxygen on the Ni center generates neutral [NiII(H2O)4(OH)(OOH)]0 species, which momentarily disconnects from the negatively charged MOL and thus avoids the over‐reduction of O2 to water. Release of H2O2 from [NiII(H2O)4(OH)(OOH)]0 regenerates [NiII(H2O)6]2+ which regains affinity to the MOL. Such a dynamically associated single‐metal center represents a new strategy for controlling selectivity in catalysis. For more information, see the Full Paper by C. Wang et al. on page 17011 ff.