Enhancing visible-light photocatalytic activity of Ag-TiO2 nanowire composites by one-step hydrothermal process

•Ag-TiO2 nanowire composites were successfully prepared by one-step hydrothermal method.•Ag deposition significantly improved the photon absorption in visible light.•Ag-TiO2 nanowire composites exhibited excellent photocatalytic activity for degradation of Rhodamine B dye. TiO2 nanowires loaded with different amounts of Ag (1–5 mol%) were successfully fabricated by one-step hydrothermal process using titanium butyrate as a precursor in alkaline solution. The products were characterized using X-ray diffraction, scanning electron microscope, transmission electron microscope, X-ray photoelectron spectroscopy and UV–Vis diffuse reflectance spectroscopy. Photocatalytic performance of all Ag-TiO2 samples was investigated by degradation of Rhodamine B dye under simulated sunlight. The result showed that Ag modification significantly improved the absorption of TiO2 nanowires in the visible region. The Ag-TiO2 nanowire composites with 3 mol% Ag demonstrated the best photocatalytic activity compared with other samples, which could be attributed to the enhancement of light harvesting and the decrease of charge recombination.