A C3N4/Bi2WO6 organic-inorganic hybrid photocatalyst with a high visible-light-driven photocatalytic activity

C3N4/Bi2WO6 heterojunction photocatalysts were successfully synthesized using consecutive hydrothermal and calcination processes. These photocatalysts were characterized using x-ray diffraction, scanning electron microscopy, transmission electron microscopy, ultraviolet-visible diffuse reflectance spectroscopy, x-ray photoelectron spectroscopy, and photoluminescence measurements. The results of these measurements indicated that the Bi2WO6 nanoparticles were approximately 30-50 nm and uniformly distributed on the surface of C3N4 lamellar structures. The 20% C3N4/Bi2WO6 displayed enhanced visible-light absorption from 432 nm to 468 nm. Photocatalytic tests also revealed that the 20% C3N4/Bi2WO6 photocatalyst exhibited significantly enhanced photocatalytic activity compared to that of pure C3N4 and Bi2WO6 under irradiation by visible light (lambda > 420 nm). Furthermore, the excellent photocatalytic efficiency of the 20% C3N4/Bi2WO6 photocatalyst was determined to be related to the formation of C3N4/Bi2WO6 heterojunctions, and their presence was found to be generally beneficial for the separation of photogenerated electron-hole pairs.