AgI Nanoparticles Evenly Dispersed on 2D Porous Bi5O7I Sheets: Simple Synthesis and Excellent Photocatalytic Performance

A series of Bi5O7I/AgI composites were successfully prepared by the co-precipitation method. Their feature and chemical structure were well characterized. The photocatalytic activity was evaluated by the degradation of Rhodamine B (RhB) under visible light. Experimental results indicated that the sizes of AgI exhibited obviously decrease through dispersing on the surface of Bi5O7I, and the as-prepared Bi5O7I/AgI composites revealed better photocatalytic activities for the degradation of RhB than separate Bi5O7I and AgI. When the mass rate of Bi5O7I in Bi5O7I/AgI composites was 40%, the as-prepared Bi5O7I/AgI (40 wt%) composites exhibited the optimum photocatalytic activity for degrading RhB, which was approximately 13 and 2.7 times higher than pure Bi5O7I and AgI, respectively. The enhanced photocatalytic performance could be attributed to complementary potentials of conduction band and valence band of Bi5O7I and AgI, which promoted the separation of the photogenerated electrons and holes. Finally, the possible mechanism for the photodegradation reaction over Bi5O7I/AgI composites was proposed.