Preparation of Phosphorus Doped Graphitic Carbon Nitride and Its Visible-Light Photocatalytic Performance on Sulfathiazole Degradation

Phosphorus doped graphitic carbon nitride (PCN) was synthesized by the combination of hydrothermal treatment and copolymerization of melamine and glyceryl phosphatidylcholine in this manuscript. To analyze the phase composition and photoelectric properties of as-prepared photocatalysts, X-ray diffraction (XRD), transmission electron microscopy (TEM), X ray photoelectron spectroscopy (XPS), ultraviolet visible diffuse reflectance spectroscopy (UV-vis DRS) and photoluminescence spectrum (PL) were performed. These results show that the P doping increased the specific surface area of PCN photocatalyst, reduced the recombination rate of photo-generated electron-hole pairs, broadened the spectral response range and improved the oxidation properties of PCN photocatalysts. The obtained PCN photocatalysts were used in the visible-light photocatalytic degradation of aqueous sulfathiazole (ST). The degradation rate of aqueous sulfathiazole (ST) over PCN under visible light irradiation was much higher than that over bulk graphitic carbon nitride (CN), and the 60% PCN (where 60% is the mass ratio of glyceryl phosphatidylcholine to melamine) photocatalyst exhibited the best activity. The results of trapping experiment indicate that the hydroxyl radical (·OH) is the dominant active species in the process of photocatalytic reaction.