Molybdenum doped tin oxide thin films for self-cleaning applications

Photo responsive SnO2 and Mc, doped SnO2 (Mo-SnO2) thin films have been produced by thermal evaporation technique. Hydrophobic-hydrophilic switching in pure SnO2 and Mo-SnO2 films are demonstrated by alternating between ultra-violet (UV) light irradiation and dark storage. Wettability studies reveal that incorporation of Mo on SnO2 thin film rapidly enhances the switching reversible transition between hydrophobic to hydrophilic in contrast to pure SnO2 thin film. Thus Mo doping in SnO2 is effective in boosting the hydrophilicity of SnO2 film. The difference in behaviour is attributed to the larger number of oxygen vacancies on Mo doping of SnO2 film which is also evident from the differences in refractive index and optical band gap of the doped and undoped films. (C) 2014 Elsevier B.V. All rights reserved.