Enhanced visible light photocatalytic performance of g-C3N4 photocatalysts co-doped with iron and phosphorus

Preparation of Fe and P co-doped g-C3N4 was described, using dicyandiamide monomer, ferric nitrate, and diammonium hydrogen phosphate as precursor. X-ray diffraction (XRD), N2 adsorption, UV–vis spectroscopy, Fourier transform infrared spectra (FT-IR), photoluminescence (PL), X-ray photoelectron spectroscopy (XPS), and photocurrent measurement were used to characterize the prepared catalysts. The results indicated that the addition of dopants inhibited the crystal growth of graphitic carbon nitride, enhanced the surface area, decreased the band gap energy, and restrained the recombination of photogenerated electrons and holes. Fe and P co-doped g-C3N4 exhibited much higher Rhodamine B (RhB) photodegradation rate and H2 production ability than that of single doped and neat g-C3N4 catalysts. The possible mechanism and doping sites of P and Fe were proposed.