Photoreactivity and Mechanism of g-C₃N₄ and Ag Co-Modified Bi₂WO₆ Microsphere under Visible Light Irradiation

In this study, C 3 N 4 @Ag-Bi 2 WO 6 with flower-like architecture was successfully prepared through a facile process. The C 3 N 4 @Ag-Bi 2 WO 6 particles with 2–4 μm diameters present remarkable enhanced visible light absorption and electron–hole separation efficiency. Compared with Bi 2 WO 6, Ag-Bi 2 WO 6, and C 3 N 4 @Bi 2 WO 6 systems, the C 3 N 4 @Ag-Bi 2 WO 6 system exhibits optimal photocatalytic activities in both the degradation of RhB and hydrogen production out of water under visible light irradiation. We propose that these results are attributed to the synergy effects of Ag, g-C 3 N 4, and Bi 2 WO 6 nanophase structures in the C 3 N 4 @Ag-Bi 2 WO 6 composites, which results in a fast electron–hole separation and slow charge recombination by a Z-scheme mechanism and ultimately in a higher photocatalytic activity.