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

This paper describes the combinational surface kinetics enhancement and surface states passivation of nickel-borate (Ni-B i ) co-catalyst for a hematite (Fe 2 O 3 ) photoanode. The Ni-B i -modified Fe 2 O 3 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 (B i ) in the Ni-B i film promotes the release of protons for the oxygen evolution reaction (OER).