Facile fabrication of highly efficient g-C3N4/Ag2O heterostructured photocatalysts with enhanced visible-light photocatalytic activity.

Highly efficient visible-light-driven g-C3N4/Ag2O heterostructured photocatalysts were prepared by a simple liquid phase synthesis method at room temperature. The composition, structure, morphology, and optical absorption properties of the as-prepared g-C3N4/Ag2O composites were characterized by XRD, FTIR, XPS, TEM, and UV-vis DRS, respectively. We found interestingly that the photogenerated charge carriers separations of the as-prepared g-C3N4/Ag2O composites were closely related to the mass ratio of g-C3N4 and Ag2O. When the mass ratio of g-C3N4 and Ag2O reached 1:4, the as-prepared composite exhibited the highest photocatalytic activity, which was almost 11 and 1.2 times as high as that of individual g-C3N4 and Ag2O, respectively. The enhancement of photocatalytic activity could be attributed to the synergetic effects between g-C3N4 and Ag2O as well as the improved dispersibility and the decreased particle size of Ag2O. Moreover, the as-prepared composites showed excellent stability toward the photodegradation of methyl orange (MO). Finally, a possible photocatalytic and charge separation mechanism was proposed.