CTAB induced hierarchical bismuth microspheres for visible-light photocatalytic study.

Nanosheet constructed bismuth microspheres were prepared through an aqueous reduction approach in the presence of CTAB molecules, with initial formed BiOCl as the precursor and hydrazine hydrate as the reductant. The flower-like morphology and platelet units of BiOCl precursor determined the evolution of hierarchical Bi microspheres through a morphology-heredity process. Trisodium citrate was introduced to keep the Bi microspheres from oxidation, the high purity in composition are beneficial to eliminate the influence of bismuth oxides. Photocatalytic properties of the hierarchical Bi microspheres were investigated under visible-light irradiation by taking the degradation of rhodamine B (RhB) dye and colorless bisphenol A (BPA) as probe reactions. 99.7% of RhB and 47.4% of BPA degradation in 3h indicate good photocatalytic property of the hierarchical Bi microspheres. Results of storing detection and recycled experiments revealed good structure stability and photocatalytic stability of the Bi microspheres, these properties are vital for practical applications of the materials. The formation mechanism of Bi microspheres and relative degradation mechanism are also proposed on the basis of experimental data.