Improved Oxygen Evolution Kinetics and Surface States Passivation of Ni-Bi Co-Catalyst for a Hematite Photoanode

This paper describes the combinational surface kinetics enhancement and surface states passivation of nickel-borate (Ni-Bi) co-catalyst for a hematite (Fe2O3) photoanode. The Ni-Bi-modified Fe2O3 photoanode exhibits a cathodic onset potential shift of 230 mV and a 2.3-fold enhancement of the photocurrent at 1.23 V, versus the reversible hydrogen electrode (RHE). The borate (Bi) in the Ni-Bi film promotes the release of protons for the oxygen evolution reaction (OER).