Synthesis and characterization of g-C 3 N 4 /Ag 2 CO 3 with enhanced visible-light photocatalytic activity for the degradation of organic pollutants

A facile, simple method was developed for the synthesis of g-C3N4/Ag2CO3 at room temperature. The samples were characterized by X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), transmission electron microscopy (TEM), diffuse reflectance spectroscopy (DRS) and Fourier transformed infrared (FT-IR) spectroscopy. The photocatalytic activity of g-C3N4/Ag2CO3 composites for the photo-degradation of methyl orange (MO) was much higher than that of the pure Ag2CO3. The kinetics of the g-C3N4/Ag2CO3 composites were proposed. The electrochemical impedance spectroscopy of g-C3N4/Ag2CO3 composites and a series of radical trapping experiment were also carried out to explore the possible photocatalytic mechanism. The results indicated that the enhanced photocatalytic activity of g-C3N4/Ag2CO3 composites under visible light irradiation was attributed to the formed heterostructure between g-C3N4 and Ag2CO3, which was beneficial to the separation of the photoinduced electron–hole pairs.