Constructing Chemical Interaction between Hematite and Carbon Nanosheets with Single Active Sites for Efficient Photo‐Electrochemical Water Oxidation

Abstract Addressing the intrinsic charge recombination of hematite (α‐Fe 2 O 3 ) is significantly important for achieving highly efficient photo‐electrochemical water oxidation but still remains challenging. Herein, this challenge is tackled by constructing chemical interaction at the interface of α‐Fe 2 O 3 and carbon nanosheets with single‐nickel sites (Ni‐NC), which can accelerate the reaction kinetics by providing additional charge transport channels and abundant active sites. The interfacial carrier path induced by the chemical coupling and the efficient single‐nickel sites work collaboratively, achieving an impressive photocurrent density of 1.85 mA cm −2 at 1.23 V versus reversible hydrogen electrode (RHE), up to 2.2 times higher than that of pure α‐Fe 2 O 3 . These findings shed light on an interface modulation strategy and provide an alternative toward utilizing unique single active sites for efficient photo‐electrochemical water splitting.