Hierarchical Composite of Ag/AgBr Nanoparticles Supported on Bi2MoO6 Hollow Spheres for Enhanced Visible-Light Photocatalytic Performance

The fabrication of multicomponent composite systems may provide benefits in terms of charge separation and the retardation of charge pair recombination. For this purpose, a hierarchical Ag/AgBr/Bi2MoO6 composite was fabricated by using prepared hierarchical floriated Bi2MoO6 hollow spheres as a supporting material. The interleaved nanoflakes assembled in the hierarchical floriated Bi2MoO6 hollow spheres contributed to the stable deposition of Ag/AgBr nanoparticles and the formation of effective nanojunctions, which led to the low recombination rates of the photoinduced electronhole pairs. The presence of double visible-light-active components in the Ag/AgBr/Bi2MoO6 nanojunction system further broadened the visible-light photoresponse range. As a result, the hierarchical Ag/AgBr/Bi2MoO6 composite exhibited a higher photocatalytic activity than both photocatalysts containing single visible-light-active components and crushed Ag/AgBr/Bi2MoO6 nanoparticles for the degradation of alizarin red S (ARS) and phenol. X-ray photoelectron spectroscopy (XPS) analyses indicated that both AgBr and Ag0 components coexist in the system, and the as-prepared composite is relatively stable. The improved photoinduced charge-transfer properties of the hierarchical Ag/AgBr/Bi2MoO6 composite were investigated by using the transient photovoltage (TPV) technique.