Electrophoretic deposition of Sn-doped TiO2 nanoparticles and its optical and photocatalytic properties

In this research, Sn-doped TiO 2 (Sn–TiO 2 ) nanoparticles were synthesized by a simple sol–gel method. The structure and composition of the as-prepared sample were investigated using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and ultraviolet–visible absorption spectroscopy. Electrophoretic deposition (EPD) technique was used to deposit thin films of Sn–TiO 2 on 316L stainless steel (316L SS) substrate. In order to achieve a fine and high-quality layer on the electrode surface, N -phenyl- p -phenylenediamine (NPPDA) was used as a new dispersant and charging agent in ethanolic suspensions. Based on zeta potential and conductivity measurements of the suspensions, an optimum concentration of the NPPDA dispersant was found to be 3.0 g l −1 . The in-situ EPD kinetics was also studied. The prepared Sn–TiO 2 film was used for the photodegradation of methylene blue (MB) under UV, visible and sun lights. The results revealed that the Sn–TiO 2 film could be able to degrade the MB under sunlight. The calculated degradations were 44, 65, and 73% after 2, 4 and 5 h, respectively. The relation between ln A 0 A and time was linear, so it was proved that the photocatalytic degradation of MB can be characterized by pseudo-first order reaction kinetics.