Visible light-driven BiOI/ZIF-8 heterostructure and photocatalytic adsorption synergistic degradation of BPA

A novel binary photocatalytic composite (BiOI/ZIF-8) was successfully constructed by solvothermal method. Its crystal morphology, chemical state of the elements and electrochemical properties were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, transmission electron microscopy, scanning electron microscopy, X-ray photoelectron spectroscopy and photoluminescence analysis. Appropriate ZIF-8 doping enhanced the separation and utilization of photogenerated electrons, promoted the capture of contaminants and rapidly produces active species, thereby accelerating the photocatalytic degradation of contaminants. Degradation experiments on BPA showed that the photocatalytic property of BiOI/ZIF-8 (0.5) was significantly improved compared with the parent material. BiOI/ZIF-8 (0.5) showed the highest reaction rate constant (0.06061 min −1 ), 9.2 times that of BiOI (0.00659 min −1 ) and 23.3 times that of ZIF-8 (0.0026 min −1 ). In addition, five cycle tests showed that BiOI/ZIF-8 was highly efficient in recycling and stability. Through capture experiments, superoxide free radicals ·OH, h − and ·O 2 − play an important role in degrading BPA, among which superoxide free radicals h + play a major role.