Bi2S3-sensitized Bi2Sn2O7 (BSO) photocatalyst (Bi2S3/BSO) was successfully synthesized through a facile and economical ion exchange method between BSO and thioacetamide (CH3CSNH2). The as-prepared photocatalysts were characterized using X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), energy-dispersive X-ray (EDX) spectroscopy, Brunauer-Emmett-Teller (BET) surface area, X-ray photoelectron spectroscopy (XPS), Raman spectra, and UV-vis diffuse reflection spectroscopy (DRS). The obtained Bi2S3/BSO composite showed excellent photocatalytic performance for decomposing rhodamine B (RhB) compared with pure BSO under visible light irradiation (lambda > 420 nm). 2% Bi2S3/BSO exhibited the highest photocatalytic activity and excessive amount of Bi2S3 would result in the decrease of photocatalytic activity of BSO. On the basis of the calculated energy band positions, the mechanism of enhanced photocatalytic activity was proposed. (C) 2015 Elsevier B.V. All rights reserved.