NiFe-oxide electrocatalysts for the oxygen evolution reaction on Ti doped hematite photoelectrodes

Nickel iron binary oxide electrocatalysts prepared from different precursors were evaluated to facilitate the oxygen evolution reaction (OER) on semiconducting metal-oxide photoelectrodes. The electrocatalysts deposited from Ni(II) and Ni(II)Fe(II) precursors had the highest activity for OER, however, their presence on the surface of the Ti doped hematite photoelectrode decreased the incident photon-to-current efficiency (IPCE) of the photoelectrode for water splitting in an alkaline electrolyte. In contrast, the NiFe-oxide deposited from the Ni(II)–Fe(III) precursor which had a lower OER activity was found to increase the IPCE of the photoelectrode by as much as a factor of 5.