Fabrication, characterization, and photocatalytic activity of anatase/rutile/SnO2 nanocomposites

Anatase/rutile/SnO2 nanocomposites have been synthesized through a sol–gel method. The crystal structure, surface morphology, chemical valence, specific surface area, and optical property of the samples were investigated by XRD, Raman, SEM, TEM, HRTEM, XPS, BET, DRS, and PL analyses. The addition of Sn promotes the phase transition from anatase to rutile. The formed anatase/rutile/SnO2 three-phase coexistence structure is beneficial to the separation of photogenerated pairs and the decrease of band gap. The photocatalytic behavior of photocatalysts was studied via the photodegradation of MB solution under xenon lamp irradiation. With the increase of Sn concentration, the photocatalytic performance of TiO2/SnO2 is improved, and all TiO2/SnO2 photocatalytic activities are higher than pure TiO2. 32%Sn–TiO2 (32%ST) exhibits the highest photocatalytic activity and the MB has been completely photodegraded in 30 min.