Morphological effect on photocatalytic degradation of Rhodamine B and conversion of active species over BaSb2O6

Both active species and morphological effect are important for antimonate photocatalysis. However, there is little research on the relationship between them. The aims of this article are to investigate the relationship between morphological effect and mutual transformation of active species during photocatalytic degradation of Rhodamine B (RhB) over BaSb2O6. The existence of active species is confirmed by electron spin-resonance spectroscopy (ESR), photoluminescence method and N,N-diethyl-p-phenylenediamine (DPD) method. The role of active species is evaluated by adding scavengers of active species during the photocatalytic degradation of RhB, and the mutual transformation of active species are investigated by observing the influence of different conditions on H2O2 in the photocatalytic processes. The results show that the concentration of (OH)-O-center dot has the greatest influence on photocatalytic activity of BaSb2O6. As the sources of (OH)-O-center dot, the production of HO2 center dot/O-2(center dot-) and surface hydroxyl groups are dependent on the morphology of the sample. The concentrations of HO2 center dot/O-2(center dot-) and surface hydroxyl groups are higher on marigold-flower-like BaSb2O6 than that on rose-flower-like BaSb2O6. The morphological effect of BaSb2O6 may be applied similarly to other antimonate photocatalysts. (C) 2014 Elsevier B.V. All rights reserved.