UV ENHANCEMENT OF THE GAS SENSING PROPERTIES OF NANO-TiO2
Tsung-Yeh Yang1, Hong-Ming Lin1, Bee-Yu Wei1,
Chuan-Yi Wu1 and Chung-Kwei Lin2
1 Department of Materials Engineering, Tatung University, Taipei 104, Taiwan, R.O.C.
2 Department of Materials Science, Feng Chia University, Taichung 407, Taiwan, R.O.C.
In this study, the gas-sensing properties of
nanocrystalline TiO2 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 TiO2 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.
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