Amorphous Fe-Mo oxides activated by hydrogen peroxide etching for enhanced electrocatalytic oxygen evolution

• Amorphous Fe-Mo oxides with rich oxygen vacancies is successfully synthesized. • Hydrogen peroxide etching introduces more oxygen vacancies . • The prepared amorphous oxides exhibit excellent activity and stability. The oxygen evolution reaction (OER), a half-reaction in electrocatalytic water splitting, involves the transfer of four electrons and significantly impacts the efficiency of electrocatalytic processes. Designing and developing OER electrocatalysts that are both cost-effective and highly efficient is essential. In this paper, amorphous Fe-Mo oxide with abundant oxygen vacancies has been synthesized via co-precipitation with subsequent hydrogen peroxide etching method. Due to the amorphous structure and plentiful defects, amorphous Fe-Mo oxide demonstrates excellent OER electrocatalytic activity, achieving an overpotential of 244 mV at a current density of 10 mA cm −2 in a 1.0 M KOH solution, outperforming commercial RuO 2 . Additionally, it exhibits prolonged stability, maintaining a consistent current density over a 30-hour evaluation period, indicating its potential for industrial applications.