Dahlia-shaped BiOClxI1-x structures prepared by a facile solid-state method: Evidence and mechanism of improved photocatalytic degradation of rhodamine B dye.

A rapid and cheap solid-state chemical process was employed to synthesize BiOClxI1-x (x=1.0, 0.75, 0.5, 0.25, 0) solid solutions with dahlia-shaped hierarchitectures. The dahlia-shaped BiOClxI1-x hierarchitectures were effectively constructed by nanoplates with a thickness about 5-13nm. The band gap structure of the solid solutions can be modulated by adjusting the composition ratio of Cl and I, which has a significant effect on the photocatalytic activity of the solid solutions. The dahlia-shaped BiOClxI1-x (x=0.75) solid solution exhibits excellent adsorption and effective photocatalytic performances for rhodamine B (RhB) under visible light irradiation, which degraded more than 98% of RhB within 60min under the visible light irradiation, it is higher than the reported bismuth oxyhalides materials. The trapping experiments confirmed that O2- and h+ played the major role in the photocatalytic process and the possible photocatalytic reaction mechanism was illustrated.