A corrosion-reconstructed and stabilized economical Fe-based catalyst for oxygen evolution

The anode activity can to a great degree limit the cathodic hydrogen evolution efficiency in an electrolyte cell. Thus, cost-efficient electrocatalysts with good water oxidation performance and stability are highly desired in widespread implementation of the hydrogen production from water splitting. This paper proposes a facile corrosion-reconstruction strategy to transform Fe surface into a Fe-Co hydroxide layer to improve the oxygen evolution activity. The as-prepared catalyst was measured to have an over-potentential as low as 320 mV at 100 mA·cm⁻², and its stability even exceeded 600 h. Surface and Raman spectroscopy analyses indicated that the catalyst experienced chemical changes from hydroxides to oxyhydroxides and Co²⁺ to Co³⁺ during oxygen evolution reaction (OER). The corrosion-reconstruction is not only an economical method to synthesize a highly efficient, stable and durable Fe-based catalysts, it also converses the detrimental corrosion into a beneficial catalyst fabrication process.