Novel synthesis of PbBiO2Cl/BiOCl nanocomposite with enhanced visible-driven-light photocatalytic activity

摘要

The first synthetic study on PbBiO2Cl/BiOCl nanocomposite preparation using a controlled hydrothermal method is reported. The composition and morphologies of the samples could be controlled by adjusting some growth parameters, including reaction pH, Pb/Bi molar ratio, and temperature. All the samples are characterized by XRD, TEM, XPS, SEM-EDS, FT-IR, BET, EPR, and UV-vis-DRS. The photodegradation activities are evaluated against the de-colorization of crystal violet (CV) and 2-hydroxybenzoic acid (2-HBA) in aqueous solution under visible light illumination. In particular, the catalytic performance illustrates the best reaction rate constant 2.763 x10(-1) h(-1) once PbBiO2Cl/BiOCl is used as the photocatalyst for the degradation of CV; which is 3.01 and 2.12 times higher than the reaction rate constant of PbBiO2Cl and BiOCl being the photocatalysts, respectively. This study reveals that PbBiO2Cl/ BiOCl can be used for repressing the recombination of photogenerated electron-hole pairs and contribute to the enhanced photocatalytic activity of semiconductors in the visible-light-driven catalysis. The possible photocatalytic degradation mechanism is studied by using different active species through EPR and adding suitable scavengers. The results reveal that the reactive O-2(-), OH, h(+), O-1(2) play the major roles in the CV degradation.