Basic photocatalytic activity of ZrO2 thin films fabricated by a sol-gel method under UV-C irradiation

The photocatalytic activity of zirconia (ZrO2) thin film fabricated by a sol-gel method was investigated using methyl red decomposition under ultraviolet C (UV-C) irradiation. The dependence of ZrO2 photocatalytic properties on annealing temperature was also investigated. The photocatalytic activity of ZrO2 was compared with that of TiO2, a standard photocatalyst material. Zirconia annealed at 500-700 degrees C has a combined tetragonal and monoclinic crystal structure, while that annealed at 800-980 degrees C has an almost exclusively monoclinic structure. The photocatalytic activity of ZrO2 annealed at 500-700 degrees C was found to be higher than that of ZrO2 annealed above 800 degrees C. The low activity of ZrO2 annealed above 800 degrees C is considered to result from the increase in interstitial O- states formed by phase transitions, which lead to increased absorption at -5.4 eV. The photocatalytic activity of ZrO2 annealed at 500-700 degrees C was approximately ten times as high as that of TiO2, which suggests that pure ZrO2 with wide bandgap energy is a promising candidate for photocatalysis under UV-C irradiation.

Automated summary

The photocatalytic activity of zirconia thin films fabricated by a sol-gel method was studied under UV-C irradiation, with those annealed at 500-700 degrees Celsius showing higher activity compared to those annealed above 800 degrees Celsius. This suggests that pure ZrO2 with wide bandgap energy is a promising candidate for photocatalysis under UV-C irradiation.