Photodegradation of gaseous C6H6 using CdO+CdTiO3 and TiO2 thin films obtained by sol–gel technique

• TiO2 and CdO + CdTiO3 thin films were performed with different Ti/Cd ratios.
• Benzene was degraded in gas phase under different conditions of relative humidity.
• High photocatalytic efficiency was observed for the CdO + CdTiO3 films Ti/Cd = 0.65.
• High efficiency can be due to the coupling of both CdO and CdTiO3 semiconductors.
• Detrimental effect on the oxidation process at high relative humidity was observed.

In this work, TiO2 and CdO + CdTiO3 multicomponent oxide thin films growth was performed with different Ti/Cd ratios (0, 0.20, 0.49, 0.60, 0.65, 0.70 and 1) by the sol–gel route in order to degrade benzene in gas phase with an initial concentration level of 110 ± 10 ppm, under different conditions of relative humidity (RH): 25%, 50% and 80% in a batch type reactor, at room temperature. The results showed a degradation near to 100% at t = 75 min, using the CdO + CdTiO3 multicomponent oxide semiconductor with a Ti/Cd ratio of 0.65. On the other hand, the TiO2 thin films reached only a degradation of 70% in t = 240 min. A decrease of the oxidation process of benzene was observed in all films studied, as the relative humidity increased.

Figure optionsDownload as PowerPoint slide