Effective photoinduced charge separation and photocatalytic activity of hierarchical microsphere-like C60/BiOCl

In order to further improve the photocatalytic performance of BiOCl, C60 modified BiOCl photocatalysts with enhanced photocatalytic activity were prepared in-situ through a typical hydrothermal method (453 K, 24 h). The morphology of the 1.0% C-60/BiOCl is completely different from that of the bare BiOCl, suggesting that C-60 significantly influences the growth of the C-60/BiOCl microsphere. The results of XRD, XPS and Raman demonstrate a strong chemical interaction exists between C-60 and BiOCl. C-60 modified BiOCl photocatalysts exhibit excellent photocatalytic activity and stability toward degradation of phenol and rhodamine (RhB) under simulated solar irradiation in comparison with the bare BiOCl. The 1.0% (wt%) C-60/BiOCl displays the best photocatalytic activity, the first-order kinetics degradation rate constants of phenol and RhB over the 1.0% C-60/BiOCl are 3 and 9 times of that over the bare BiOCl, respectively. The reactive free species were detected by trapping and electron spin resonance (ESR) experiments under simulated sunlight irradiation, the results reveal that superoxide free radical (O-2(center dot-)) and hole (h(+)) are the major active free radicals, furthermore the 1.0% C-60/BiOCl produces more active free radicals. On account of all the observations, the high separation rate of photogenerated electrons and holes is in favor of the relative high photocatalytic activity of C-60/BiOCl, originating from the intense chemical interaction between BiOCl and C-60.