Dealloying synthesis of SnO2TiO2 solid solution and composite nanoparticles with excellent photocatalytic activity

A novel rutile TiO2/Sn0.42Ti0.58O2 composite photocatalyst was first synthesized by dealloying method using Cu60Ti30Sn10 amorphous ribbons as precursors. The prepared sample was characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV–vis diffuse reflectance spectroscopy (DRS) and photoluminescence techniques (PL). The results of XRD, SEM and TEM and XPS show that the rutile TiO2/Sn0.42Ti0.58O2 has been successfully synthesized and the sample is composed of large quantities of fine nanoparticles with sizes of 15–60 nm, which have been assembled into a much larger structure with novel football-like surface. While PL and DRS results show that rutile TiO2/Sn0.42Ti0.58O2 has a lower PL intensity compared with pure rutile TiO2 and Sn0.42Ti0.58O2 and an intermediate value of band gap energy (3.01 eV) between those of the rutile TiO2 (2.97 eV) and Sn0.42Ti0.58O2 (3.04 eV). Moreover, the photocatalytic activities of the samples were evaluated by decomposing rhodamine B (RhB) dye (10 mg/L) under the ultraviolet (UV) light irradiation. The results show that the photocatalytic performance of rutile TiO2/Sn0.42Ti0.58O2 is much higher than those of pure rutile TiO2 and Sn0.42Ti0.58O2.