Water oxidation electrocatalysis with iron oxide nanoparticles prepared via laser ablation

Iron oxide nanoparticles (FeOx NPs, 5–30 nm size) prepared via laser ablation in liquid were supported onto Indium Tin Oxide conductive glass slides by magnetophoretic deposition (MD) technique. The resulting FeOx@ITO electrodes are characterized by a low amount of iron coverage of 16–50 nmol/cm2, and show electrocatalytic activity towards water oxidation in neutral phosphate buffer pH 7 with 0.58 V overpotential and quantitative Faradaic efficiency towards oxygen production. XPS analysis on the oxygen region of the FeOx films reveals a substantial hydration of the surface after catalysis, recognized as a crucial step to access reactivity.