Sulfate-doped NiOOH-Ni(OH)2 nanosheet array for industrial co-production of hydrogen and potassium diformate

Electrocatalytic water splitting for green hydrogen is hindered by the slow oxygen evolution reaction (OER). Replacing OER with ethylene glycol oxidation (EGOR) offers an energy-saving route, co-producing valuable chemicals, but requires efficient, stable, and low-cost catalysts. Here, we report a sulfate-doped NiOOH-Ni(OH)2 catalyst (denoted S-NiOOH-Ni(OH)2). SO42− doping significantly boosts intrinsic activity, enabling exceptional EGOR performance (only 1.45 V for ∼650 mA cm−2). In situ studies reveal that a unique “structural locking” effect stabilizes the highly active β-NiOOH phase within the composite, differing from conventional reconstruction. Notably, we successfully scaled up this catalyst to an industrial-scale electrolyzer (anode area: 1386 cm2) and constructed an integrated electrochemical-conventional chemical coupling system, which stably produced 290 L of hydrogen and kilogram-scale high-purity potassium diformate (KDF) per batch. Techno-economic analysis confirms strong commercial viability, projecting $7.1 million annual profit and a payback period under one year. This work bridges advanced catalyst design to industrial biomass valorization coupled with hydrogen production.