Oxygen evolution reaction (OER) is critical for optimizing renewable energy systems, including metal–air batteries and water electrolysis. One major challenge for OER is to develop durable and cost‐effective electrocatalysts with high catalytic performance. Herein, a controllable ion‐exchange method to synthesize amorphous zinc/cobalt–iron hydroxide‐based hollow nanowall arrays (A‐Zn/Co–Fe HNAs) derived from bimetallic metal–organic frameworks (MOFs) on carbon cloth is reported. The amorphous characteristic enables the presented materials with more electrocatalytic sites and short diffusion paths for rapid access to the electrolyte, achieving efficient charge transfer for OER. The optimized nanostructure of A‐Zn/Co–Fe HNAs via tuning the amount of iron sulfate in the reaction solution delivers a low overpotential of 226 mV to reach a current density of 10 mA cm−2 with a small Tafel slope of 37.81 mV dec−1 while exhibiting high durability at varied current densities over 80 h. The remarkable electrochemical performance can be attributed to the synergistic effect from chemical elements of Zn, Co–Fe, and a robust hollow structure. This simple method of fabricating bimetallic‐MOF‐derived amorphous Zn/Co–Fe HNAs on carbon cloth can be applied as a practical platform for other OER electrocatalysts.

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Enzymatic polymerization is widely used in the fabrication of hydrogels due to its high biocompatibility and controllability. However, it usually suffers from the destabilization of enzymes under hard conditions and the requirement of diketones substrates to fulfill radical polymerization. Herein, multifunctional magnetic hydrogels (MMHs) are constructed in the presence of hydrogen peroxide (H 2 O 2 ) by iron oxide nanoparticle (Fe 3 O 4 NP)-mediated radical polymerization. In comparison with the natural enzyme initiation systems, a Fe 3 O 4 NPs/H 2 O 2 system can initiate the polymerization of poly(ethylene glycol) diacrylate instantaneously at ambient temperature without the substrate and can display higher catalytic activity under acidic conditions. The resultant magnetic composites have multifunctionality of the integration of magnetism, superwetting, and photothermal responsiveness, as well as the catalytic activity of a mimic enzyme, achieving effective rapid separation of oil-in-water emulsions and fast degradation of organic dye with good recyclability.

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