Enhanced photo-induced charge separation and sun light-driven photocatalytic performance of g-C3N4 modified by phosphate

Phosphate-decorated g-C3N4 photocatalysts with enhanced photo-induced charge separation in visible light region and sun light-driven photocatalytic performance were prepared by a facile pore impregnation approach. The photocatalysts were characterized by Brunauer–Emmett–Teller method, X-ray diffraction, scanning electron microscopy, UV–Vis diffuse reflectance spectroscopy, and surface photovoltage spectroscopy, respectively. The results show that decorating g-C3N4 by phosphate increases the adsorption of rhodamine B on the photocatalysts and the rate of photo-induced charges separation, especially the photo-induced charge separation rate in visible light region. The photocatalytic activities of g-C3N4 decorated by phosphate for decolorization of rhodamine B aqueous solution were evaluated. The result shows that when the concentration of phosphate is 4 M, g-C3N4 modified exhibits the best photocatalytic activity under simulated solar irradiation and the possible reason is discussed.