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, N-2 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.