The alkaline oxygen evolution reaction is a key step in producing green hydrogen through water electrolysis, but its large-scale industrial application remains limited due to challenges with current electrocatalysts—particularly in terms of scalability, efficiency, and long-term stability. Here we show an industrially scalable synthesis of an active NiFe layered double hydroxide (NiFe-LDH) catalyst using a room-temperature, atmospheric-pressure route. The process involves homogeneous alkalinization, where chloride ions nucleophilically attack an epoxide ring, producing a low-dimensional, defect-rich NiFe-LDH with pronounced iron clustering. In-situ spectroscopy and ab-initio calculations reveal that these structural features maximize the conversion of the NiFe-LDH to the catalytic active phase and minimize the energy barrier, improving catalytic efficiency. When used as the anode in an anion exchange membrane water electrolyzer operating at 70 °C, our material delivers 1 A cm⁻² at 1.69 V in a 5 cm² full-cell setup, with notable durability compared to conventional NiFe-LDHs. This scalable approach could considerably lower the cost of green hydrogen production by enabling more efficient alkaline electrolyzers.

The steam reforming of ethanol (ESR) has been studied by near ambient pressure XPS (NAP-XPS), extended X-ray absorption fine structure (EXAFS), and X-ray absorption near edge structure (XANES) under in situ conditions in the ALBA synchrotron facility at 200–580 °C and S/C = 3 over different cobalt-based catalysts that showed different catalytic performances: Co₃[Si₂O₅]₂(OH)₂ (Co-talc), [Co₂Mg₄Al₂(OH)₁₆]CO₃·4H₂O (Co-hydrotalcite shortened to Co-HT) calcined at 550 °C, and Co₃O₄ (Co-spinel). Both Co-spinel and Co-talc yield to a greater or lesser degree metallic cobalt under ESR conditions. While Co-spinel shows a complete reduction to metallic cobalt under the conditions used for the XANES measurements, the more bulk-sensitive Co-talc sample exhibits only a partial reduction. On the other hand, under the ESR conditions used with the NAP-XPS, a more surface sensitive technique, the results indicate a higher reduction degree for the Co-talc sample in comparison to the Co-spinel sample. In contrast, the catalyst prepared from the Co-HT does not show metallic cobalt traces under the experimental conditions used with both techniques. On comparison of these three cobalt-based catalysts, the stable operation exhibited by Co-HT under ESR reaction conditions is justified by the absence of metallic cobalt formation under in situ conditions, which is identified as being responsible for the carbon deposition phenomenon that triggers the deactivation suffered by most cobalt-based catalysts during ESR.