Facile ultrasonic deposition of SnO2 nanoparticles on TiO2 nanotube films for enhanced photoelectrochemical performances

Abstract

After a self-organized TiO₂ nanotube film on a Ti substrate was fabricated through anodic oxidation, SnO₂ nanoparticles were deposited on the film by a facile ultrasonic assisted deposition method. The photoelectrochemical performances of the prepared SnO₂–TiO₂ nanotube composite films were evaluated by measuring their incident photon to current conversion efficiencies, transient photocurrents, and photopotentials. The results demonstrated that the deposited SnO₂ nanoparticles could greatly enhance the photoelectrochemical performance of the TiO₂ nanotube film. The SnO₂–TiO₂ nanotube composite films were highly sensitive to white light illumination. A maximum incident photon to current conversion efficiency of 89.98% at 335 nm wavelength and a maximum photocurrent density of 75.4 μA cm⁻² were achieved for the composite film prepared by 20 min ultrasonic deposition. The composite film could be applied in photoelectrochemical anticorrosion, and could provide a better photocathodic protection effect on stainless steel in a corrosive NaCl solution than that provided by the pure TiO₂ nanotube film.