Preparation, characterization and photoelectrochemical properties of hydrophilic Sn doped TiO₂ nanostructures

Abstract Hydrophilic Sn doped TiO₂ nanostructured thin films have been fabricated using a sol-gel method, and followed by calcination at 450 C. The samples are characterized by means of XRD, Raman, SEM and contact angle measurements. The XRD and Raman studies revealed that, the higher Sn doping content (3 at%) leads to the formation of mixed phases of TiO₂. SEM micrographs revealed that all samples are porous in nature. The contact angle of TiO₂ nanostructured films varied between 19 and 37 depending upon the Sn content. All the samples are photoelectrochemically active and 2% Sn doping significantly enhances the photoelectrochemical ability of TiO ₂ film. The highest photocurrent density of 20 μA cm^-2 is measured for 2 at% Sn doped TiO₂ in 0.2 M Na₂SO ₄ electrolyte, on light irradiation. Time dependent photoresponse tests have been carried out by measuring the photocurrent under chopped light irradiation.