Hierarchical flower-like BiOI_xBr_((1-x)) solid solution spheres with enhanced visible-light photocatalytic activity

摘要

A series of hierarchical BiOIxBr(1 - x) (0 = x = 1) solid solution architectures assembled from nanosheets were fabricated by a facile polyvinylpyrrolidone K30 (PVP) assisted solvothermal strategy using ethylene glycol (EG) as solvent. To examine the photocatalytic performances of the as-prepared samples, photocatalytic degradation experiments were carried out under visible-light using methyl orange (MO) as objective pollutant. The experimental results reveal that the as-synthesized BiOIxBr(1 - x) solid solution samples are of tetragonal crystal phase and exhibit morphology- and composition-dependent visible-light photocatalytic activities. The difference in the photocatalytic performance of all the BiOIxBr(1 - x) samples was discussed in depth based on the experimental results. It was found that BiOIxBr(1 - x) solid solutions with hierarchically spherical structure (the sample R75) possess the highest photocatalytic activity on account of its hierarchical nanostructure, large specific surface area, strong absorption of visible-light, as well as the enhanced separation efficiency of photogenerated carriers. Furthermore, the hierarchical flower-like BiOIxBr(1 - x) solid solution spheres (the sample R75) also has high activity for photocatalytic decomposition of colorless bisphenol A (BPA) under visible-light. This work may provide a new perspective for the development of efficient visible-light photocatalysts for environmental pollution treatment.