Accelerating transfer of photogenerated charge carriers by loading PtOx on Cr2Bi3O11 nanorods to enhance photocatalytic activity in water detoxification and splitting

Abstract

As a new type of visible-light-driven bismuth-based photocatalyst, Cr2Bi3O11 exhibited potentials in photodegradation of organic pollutants and water splitting for oxygen evolution. However, its photocatalytic activity still needs to be further improved. Herein, an in-situ photoreduction route was employed to anchor PtOx onto the surface of Cr2Bi3O11 for improved carrier transport and enhanced photocatalytic activity. The high crystallinity and uniform crystal structure of the Cr2Bi3O11 nanorods matrix were beneficial to evenly deposit the PtOx nanodots (diameter: 0.5 nm–2.0 nm). The optimal PtOx modified Cr2Bi3O11 (1.0Pt-Cr2Bi3O11) exhibited higher photocatalytic activity in organic pollutants (i.e. phenol, chlorophenol and tetracycline) removal than other noble metals (Ag, Au, and Pd) modified Cr2Bi3O11. Besides, 1.0Pt-Cr2Bi3O11 also exhibited enhanced activity in oxygen evolution (210.5 μL/gcat/h, 4.3 times higher than pristine Cr2Bi3O11). The PtOx can effectively capture the photogenerated electrons, hence repressing electron/hole recombination and providing active sites for charge-transfer reactions.