LAUSR

Abstract Interface engineering is a very important issue in achieving high efficiency in heterojunction photocatalysts. Herein, we report an originally designed heterojunction photocatalyst with seamless contact. Its novelty includes the following two respects: (1) two Fe-based oxides, i.e., SnFe2O4 and hematite Fe2O3 (α-Fe2O3), with suitable band structures were selected to promote charge separation, and (2) a seamless contact was achieved at the interface taking advantage of the commonly shared Fe element, i.e., converting partial of the Fe ions on the surface of micro-octahedrons SnFe2O4 nanocrystals into α-Fe2O3 through thermal treatment (Octa-SnFe2O4/α-Fe2O3). Characterization results confirmed the formation of seamless contact with large area at the interface, and the significantly enhanced Z-scheme charge separation efficiency. The seamless Octa-SnFe2O4/α-Fe2O3 heterojunction could deliver a higher CO2 photocatalytic reduction activity with production rates of 2.87 μmol/g/h for CO and 0.64 μmol/g/h for CH4, which is 13.7 times and 6.4 times higher than Octa-SnFe2O4, and 2.3 times and 5.3 times than those of conventionally prepared SnFe2O4/α-Fe2O3 composite counterparts. This work indicated that the ferrite-based close-contacted heterojunctions can be further investigated as promising photocatalysts in the environmental and energy applications.