| Summary: | Solar light active photocatalyst was prepared as silver phosphate (Ag<sub>3</sub>PO<sub>4</sub>) coating on titania–silica (TiO<sub>2</sub>–SiO<sub>2</sub>) microspheres. Titania–silica microsphere was obtained by spray drying TiO<sub>2</sub>–SiO<sub>2</sub> colloidal solutions, whereas Ag<sub>3</sub>PO<sub>4</sub> was applied by wet impregnation. XRD on the granules and SEM analysis show that the silver phosphate particles cover the surface of the titania–silica microspheres, and UV-visible diffuse reflectance analysis highlights that Ag<sub>3</sub>PO<sub>4</sub>/TiO<sub>2</sub>–SiO<sub>2</sub> composites can absorb the entire visible light spectrum. BET measurements show higher specific surface area of the composite samples compared to bare Ag<sub>3</sub>PO<sub>4</sub>. Photocatalytic activity was evaluated by dye degradation tests under solar light irradiation. The prepared catalysts follow a pseudo-first-order rate law for dye degradation tests under solar light irradiation. The composite catalysts with an Ag<sub>3</sub>PO<sub>4</sub>/TiO<sub>2</sub>–SiO<sub>2</sub> ratio of 1:1.6 wt% show better catalytic activity towards both rhodamine B and methylene blue degradation and compared with the results with uncoated TiO<sub>2</sub>–SiO<sub>2</sub> microspheres and the benchmark commercial TiO<sub>2</sub> (Evonik-P25) as a reference. The composite photocatalyst showed exceptional efficiency compared to its pristine counterparts and reference material. This is explained as having a higher surface area with optimum light absorption capacity.
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