Preparation of the floating HGMs-Ag3PO4 composites and the visible-light photocatalytic properties

The hollow glass microspheres (HGMs) with low density were used as the support to obtain the floating visible-light photocatalysts (HGMs–Ag3PO4) composites, in which silver orthophosphate (Ag3PO4) was dispersed on the surface of HGMs via silane coupling agents. The morphology, crystal structure and optical property of the HGMs-Ag3PO4 composites were characterized and the contents of Ag3PO4 dispersed on the surface of HGMs were quantified by atomic absorption spectrometry (AAS). Methylene blue (MB) was selected as the typical organic pollutants to evaluate the photocatalytic activity of HGMs-Ag3PO4 composite photocatalysts. The photo-catalytic rate of the floating composites was larger than the sinking composites and even pure Ag3PO4. Ag3PO4 particles could be dispersed well on the HGMs. The floating composites has a larger light contact area and the increased photo-catalytic activity sites even at the low Ag3PO4 loading. This work may open up a new insight for the floating photocatalyst to degrade organic dye on account of the low density and high visible-light responsiveness.