Facile preparation of heterostructured Bi2O3/Bi2MoO6 hollow microspheres with enhanced visible-light-driven photocatalytic and antimicrobial activity

Hierarchical β-Bi2O3/Bi2MoO6 heterostructured flower-like microspheres assembled from nanoplates with different β-Bi2O3 loadings (0–26.5 mol%) were synthesized through a one-step template-free solvothermal route. Under visible-light illumination (λ > 420 nm), over 99% of rhodamine B was degraded within 90 min on the 21.9 mol% of β-Bi2O3 loading Bi2O3/Bi2MoO6 microspheres. The remarkable enhancement of photocatalytic activity of the hierarchical Bi2O3/Bi2MoO6 micro/nanostructures can be attributed to the effective separation of the photoinduced charge carriers at the interfaces and in the semiconductors. The electrons (e−) are the main active species in aqueous solution under visible-light irradiation. The Bi2O3/Bi2MoO6 also displays visible-light photocatalytic activity for the destruction of E. coli. In addition, the β-Bi2O3 in the hierarchical Bi2O3/Bi2MoO6 microspheres is very stable and the composite can be easily recycled by a simple filtration step, thus the second pollution can be effectively avoided. A possible photocatalytic mechanism was proposed based on the experimental results.