▎ 摘 要
Photocatalytic technologies capable of using solar energy for environmental restoration have much progressed with the increasing environmental concern. In this study, the ternary photocatalyst Ag3PO4/NG/g-C3N4 conforming to the Z-scheme mechanism was prepared by a facile in-situ deposition method. Its morphology, chemical composition and optical property were determined by X-ray diffraction analysis, scanning electron microscopy, transmission electron microscope, Fourier transform infrared, X-ray photoelectron spectroscopy and UV-vis diffuse reflectance spectroscopy. Such photocatalyst (0.50 g/L loading) achieved the highest 93.6% degradation rate of tetracycline (TC), and 72% mineralization rate of TC comparing with single Ag3PO4 (25% mineralization rate of TC). The detection of reactive oxidative species indicates that the photodegradation of TC is mainly caused by holes, O-2(-) and center dot OH. The synergistic effect of Ag3PO4, nitrogen-doped graphene (NG) and gC(3)N(4) in the composite accelerates the separation and migration of photogenerated carrier via a solid electron mediator NG, and simultaneously inhibits the photo-corrosion of Ag3PO4, thereby improving the photo-stability of the ternary photocatalyst.