Effects of redox mediators on α-Fe2O3 exposed by {012} and {104} facets for photocatalytic water oxidation

•The α-Fe2O3 exposed by {012} and {104} facets can facilitate the reduction of IO3−.•The O2 evolution activity (309.4 μmol h−1 g−1) of α-Fe2O3 photocatalyst mainly exposed by {012} and {104} facets is 84 times higher than that (3.68 μmol h−1 g−1) of α-Fe2O3 mostly exposed by {101} and {111} planes.•This work may open the door for further development of enhanced Z-scheme photocatalytic systems.

The mechanism study of redox mediator to transfer the photogenerated electrons is extremely desirable for artificial Z-scheme photocatalytic systems. Here we find that the α-Fe2O3 exposed by {012} and {104} facets can facilitate the reduction of IO3−, which results in increasing the activity of photocatalytic water oxidation significantly. By employing NaIO3 as an electron acceptor, the O2 evolution activity (309.4 μmol h−1 g−1) of α-Fe2O3 photocatalyst mainly exposed by {012} and {104} facets is 84 times higher than that (3.68 μmol h−1 g−1) of α-Fe2O3 mostly exposed by {101} and {111} planes. We anticipate that the findings in this work may open the door for further development of enhanced Z-scheme photocatalytic systems.

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