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The integration of Fe dopant and interfacial FeOOH into Ni‐MOFs [Fe‐doped‐(Ni‐MOFs)/FeOOH] to construct Fe−O−Ni−O−Fe bonding is demonstrated and the origin of remarkable electrocatalytic performance of Ni‐MOFs is elucidated. X‐ray absorption/photoelectron spectroscopy and theoretical calculation results indicate that Fe‐O−Ni−O−Fe bonding can facilitate the distorted coordinated structure of the Ni site with a short nickel–oxygen bond and low coordination number, and can promote the redistribution of Ni/Fe charge density to efficiently regulate the adsorption behavior of key intermediates with a near‐optimal d‐band center. Here the Fe‐doped‐(Ni‐MOFs)/FeOOH with interfacial Fe−O−Ni−O−Fe bonding shows superior catalytic performance for OER with a low overpotential of 210 mV at 15 mA cm−2 and excellent stability with ≈3 % attenuation after a 120 h cycle test. This study provides a novel strategy to design high‐performance Ni/Fe‐based electrocatalysts for OER in alkaline media. [ABSTRACT FROM AUTHOR]

Two-dimensional transition metal hydroxides are greatly limited in the application of the electrocatalytic oxygen evolution reaction (OER) due to its large and inert basal planes. Herein, we report a one-step in situ etching hydrothermal method to construct Co(OH)2 and Ni(OH)2 heterostructure nanomaterials, successfully activating the basal plane of Co(OH)2. The abundant lattice strains that appear at heterogeneous interfaces cause a downshift of the d-band center of Co in Co(OH)2 and promote the desorption of oxygen during the OER process, which accelerates reaction kinetics of the OER and improves catalytic activity effectively. Furthermore, the electron interaction at the Co(OH)2/Ni(OH)2 interfaces leads to charge polarization, which will regulate the adsorption and dissociation of H2O molecules and enhances mass and electron transfer. Owing to the above advantages of Co(OH)2/Ni(OH)2 interfaces, the as-prepared composite catalysts show an excellent OER catalytic performance with a low overpotential of only about 270 mV at 20 mA cm−2, maintaining long-term catalytic stability for more than 24 h at 20 mA cm−2. [ABSTRACT FROM AUTHOR]

The multi metal organic frameworks (BTC-CoNiFeZn) were used as the precursors of in situ structure reconstruction in alkaline solution, and we synthesized hierarchical porous Ni,Fe-codoped Co-hydroxide nanowire array (Ni0.8Fe0.2/Co-H NAs/NF) catalyst for the oxygen evolution reaction (OER). Benefiting from the rational micro-structure, rich ion-accessible nanopores, and abundant defect sites, the target catalysts possess enhanced intrinsic activity. The obtained Ni0.8Fe0.2/Co-H NAs/NF catalysts show superior OER catalytic activity with a low overpotential of 231 mV at 10 mA cm−2, a small Tafel slope of 32.9 mV dec−1, and high cycle stability for 135 h with performance degradation of only about 4.4%. [ABSTRACT FROM AUTHOR]