Novel synthesis of bismuth oxyiodide/graphitic carbon nitride nanocomposites with enhanced visible-light photocatalytic activity

摘要

The first systematic synthetic study of bismuth oxyiodide/graphitic carbon nitride (BiOxIy/g-C3N4) nanocomposite preparation using a controlled hydrothermal method is reported. The structure and morphology of BiOxIy/g-C3N4 photocatalysts are characterized by XRD, TEM, FT-IR, HR-XPS, FE-SEM-EDS, UV-vis-DRS and BET. The photodegradation activities are evaluated against the decolorization of crystal violet (CV) in aqueous solution under visible light illumination. In particular, the catalytic performance illustrates the best reaction rate constant, being 0.170 h(-1) using Bi7O9I3/Bi5O7I/g-C3N4 composite as the photocatalyst; which is 5, 4, and 1.5 times higher than the reaction rate constant of BiOI, g-C3N4, and Bi7O9I3/Bi5O7I, as photocatalysts, respectively. From the quenching effects of different scavengers, the EPR results demonstrate that the reactive O-2(center dot-) plays the major role and h(+) and (OH)-O-center dot play minor roles in the CV degradation. The probable photodegradation mechanisms are proposed and discussed in this research. This work is useful for the synthesis of BiOxIy/g-C3N4 and the photocatalytic degradation of the CV for future applications in environmental pollution and control.