Photodegradation of Orange II by ZnO and TiO2 powders and nanowire ZnO and ZnO/TiO2 thin films

The present study is focused on photocatalytic degradation of the organic azo-dye Orange II in water solutions using TiO2 and ZnO powders or bare and TiO2 doped ZnO nanowire thin films. Commercial anatase TiO2 and ZnO are used for the photocatalytic experiments in slurry. The ZnO seeded substrates are prepared by repetition of four seed deposition cycles from zinc acetate solution using spin coating technique. The ZnO nanowires array films are obtained via wet chemical method. The ZnO and TiO2 doped ZnO nanowire thin films are investigated by SEM and X-ray diffraction. The photocatalytic tests are performed in cylindrical glass reactors under UV or visible light irradiation. The pollutants concentrations are 20 ppm Orange II for slurry and 10 ppm for film photocatalysis. The dyes photodegradation is observed spectrophotometrically.