Dual visible-light active components containing self-doped Bi2O2CO3/g-C3N4 2D-2D heterojunction with enhanced visible-light-driven photocatalytic activity

The (CO3)(2-)self-doped Bi2O2CO3/g-C3N4 (C-BOC/g-C3N4) unique 2D-2D heterostructure has been developed via a mixed-calcination method. This heterostructure is confirmed by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), SEM-mapping, and diffuse reflection spectroscopy (DRS). Due to the charge interaction, it is interesting to observe that C-BOC nanosheets are assembled on g-C3N4 in a surface-surface coupling way, which enables an intimate interfacial interaction between the two components. The photocatalytic activity is evaluated by photodegradation of Rhodamine B (RhB) under visible light (lambda>420nm). It is found that all the C-BOC/g-C3N4 composites showed highly enhanced photocatalytic activity. Electrochemical impedance spectra (EIS) measurement revealed that the largely promoted charge transfer derived from the well matchable band structure and intimate interfacial interactions between the two visible-light active components is responsible for the photoactivity enhancement. Besides, the active species trapping and center dot O(2)(-)quantitation experiments are conducted to disclose the photocatalytic mechanism. (C) 2016 Elsevier B.V. All rights reserved.