Enhanced Visible Light Photocatalytic Performance of G-C3N4 Photocatalysts Co-Doped with Gold and Sulfur for Degradation of Persistent Pollutant (Rhodamine B)

In order to overcome the intrinsic drawback of pristine g-C3N4, a nano-composite photo-catalyst Au/S-C3N4 with controllable nanoscale gold (Au) particles was successfully synthesized by a facile liquid chemical preparation process. It was found that the content of chloroauric acid (AuCl3 center dot HCI center dot 4H(2)O) play crucial role in both the diameter and the density of the Au nanoparticles. The results showed that as-prepared Au/S-C3N4 nanosheets with 2 wt% Au loaded content exhibited excellent photocatalytic decomposition of RhB under visible light irradiation as compared with other Au loadings (i.e., 1 wt%, 2 wt%, 3 wt%, 4 wt% and 6 wt%). The photocatalytic activity of Au/S-C3N4 with 2 wt% Au loading was twice higher than that of bare S-C3N4(0.00955 min(-1)). The enhanced performance could be attributed to the synergic effect of gold and sulfur on g-C3N4. A possible mechanism for elucidating the better performance of Au/S-C3N4 is also proposed and discussed in detail in this work.