Mesoporous TiO2 with 20 nm particle size was attached onto the surface of Ag3PO4 crystals (200nm to 400 nm in diameter). The special mesoporous TiO2 shell hindered Ag3PO4 from being dissolved into the solution, which reduced the number of aqua-Ag ions generated from Ag3PO4 crystal, thereby protecting Ag3PO4 from photocorrosion without decreasing its visible-light absorption. TiO2@Ag3PO4 catalyst had high visible-light photocatalytic activity because of the presence of narrow-band-gap Ag3PO4. Compared with pure Ag3PO4, the adsorption capacity of TiO2@Ag3PO4 toward rhodamine B (RhB) increased from 1.1% to 14.8% because of the mesoporous structure of TiO2. The composite TiO2@Ag3PO4 catalyst with molar ratio 0.5:1 exhibited the highest degradation efficiency. About 100 mL of 10 mg/LRhB can be totally degraded within 12 min in presence of 0.05 g of catalyst. (C) 2015 Elsevier Ltd. All rights reserved.