A plasmonic photocatalyst of Ag/AgBr nanoparticles coupled with g-C3N4 with enhanced visible-light photocatalytic ability

A plasmonic photocatalyst of Ag/AgBr/g-C3N4 was prepared by a solvothermal method. X-ray powder diffraction (XRD), transmission electron microscopy (TEM), UV–vis absorption spectra (in the diffuse reflectance spectra mode), photoluminescence (PL) emission spectra, and infrared (IR) spectra have been employed to determine the structure, morphology and optical property of the as-prepared Ag/AgBr/g-C3N4 composite. The interaction between Ag/AgBr and g-C3N4 has been observed by X-ray photoemission spectroscopy (XPS) analysis, and which is facile to the electron transfer between Ag/AgBr and g-C3N4 and result in the enhancing photocatalytic activity of Ag/AgBr/g-C3N4 composite. The Ag/AgBr/g-C3N4 showed much higher photoactivity than the simple mixing of Ag/AgBr and g-C3N4 with the same amount. Besides, the high dispersion of Ag/AgBr anchored on the surface of g-C3N4 was also assumed to be responsible for the enhanced activity and good recycling ability. The 17.8 at.% Ag/AgBr/g-C3N4 showed the highest photoactivity, the degradation rate constant of 17.8 at.% Ag/AgBr/g-C3N4 was as high as 18.3 times to that of the pure g-C3N4. The relationship between the photocatalytic activity and the structure of Ag/AgBr/g-C3N4 hybrid materials was discussed and the possible reaction mechanism was proposed.