Facile synthesis of novel hierarchical graphene–Bi2O2CO3 composites with enhanced photocatalytic performance under visible light

A facile template-free hydrothermal approach is developed to synthesize hierarchical flower-like graphene–Bi2O2CO3 microcomposites. The as-prepared samples were systematically characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, Raman spectroscopy, Fourier transform infrared spectroscopy, N2 adsorption–desorption and UV-visible diffuse reflectance spectroscopy. The photocatalytic activity of the as-prepared samples was evaluated towards degradation of Rhodamine B (RhB) under visible light. Compared to hierarchical Bi2O2CO3, hierarchical flower-like graphene–Bi2O2CO3 microcomposites show enhanced photocatalytic activity. In addition, our results indicate that both the physico-chemical properties and associated photocatalytic activity of graphene–Bi2O2CO3 composites are shown to be dependent on graphene loadings. The highest photocatalytic performance can be achieved for the graphene–Bi2O2CO3 microcomposites with 1.0 wt% graphene. The underlying mechanism responsible for the formation of graphene–Bi2O2CO3 composites and enhanced photoreactivity was discussed. Results from this study illustrate an entirely new approach to fabricate semiconductor composites containing graphene–bismuth with high visible-responsive photocatalytic performance.