UV Light Activation of TiO_2-Doped SnO_2 Thick Film for Sensing Ethanol at Room Temperature

摘要

TiO_2-doped SnO_2 nanopowder is synthesized via a sol-gel method and characterized by atomic force microscopy and X-ray diffraction. Using this nanopowder, we have fabricated a novel semiconductor gas sensor that is sensitive to UV light illumination. We find that gas-sensing properties of TiO_2-doped SnO_2 sensor can be enhanced significantly under the exposure of UV light. The sensor exhibits a high sensitivity of 25 and rapid response-recovery times of 8 s and 24 s, respectively, under an ethanol gas of up to 100 ppm at room temperature (323 K). This suggests the possibility of development of a gas sensor for detecting ethanol at room temperature.