UV enhancement of the gas sensing properties of nano-TiO2

In this study, the gas-sensing properties of nanocrystalline TiO 2 are enhanced by submitting the sensor system to UV light irradiation. TiO2 gas sensing material based on nanosized particles is produced by gas condensation method. The crystal structure and ceramic microstructure of the powders are determined by TEM and XRD. Structural and morphological studies as well as UV irradiation are carried out in order to investigate their influence on the sensing properties of TiO2 sensor. The sensitivity of the TiO2 sensor is affected by the presence of O2 or O- on the TiO2 surface that is enhanced by the photocatalytic effect. Gaseous CO is detected under UV light illumination. The results indicate that the sensing properties of TiO 2 are affected by the wavelength and the intensity of the UV light. The photocatalytic activity enhances the sensitivity of the nano-TiO2 sensors by more than 30 times.