An etching and re-growth method for the synthesis of bismuth ferrite/MIL-53(Fe) nanocomposite as efficient photocatalyst for selective oxidation of aromatic alcohols

Among MOFs, the Fe-based ones (such as MIL-53(Fe)) show impressive visible light response due to the extensive presence of Fe-O clusters, but their photo-activities are often restrained by severe recombination of electron-hole pairs. To circumvent this limitation, we developed an in-situ etching-and-regrowth strategy for the fabrication of heterojunctions. Through the partial destruction of the external surface of a 3D MIL-53(Fe) bipyramid, we generated bismuth ferrite (BFO) nanosheets on its surface. The rough surface of the as-fabricated composite is beneficial for light absorption as well as enlargement of specific surface area and exposure of active sites. Furthermore, the interfaces between MIL-53(Fe) and BFO accelerate the separation and transfer of charge carriers owing to the co-presence of FeO bonds in both components. The obtained composites show outstanding catalytic activity as well as excellent stability for the selective oxidation of benzyl alcohols to the corresponding aldehydes under visible light irradiation.