High sensitivity gas sensors based on SnO2 nanowires

Network structure of SnO
₂
nanowires were fabricated on the electrodes and its gas sensing propertires for NO
₂
were examined. The nanowires were synthesized by thermal evaporation process at low temperature of 600~700degC. The diameter of the nanowires ranged from 50 nm to 200 nm depending on the processing temperature and the mixed oxygen content with Ar. X-ray diffraction analysis and transmission electron microscopy analysis indicated that the SnO
₂
nanowires are single crystals. At the concentration of NO
₂
of 20 ppm, the value of the sensitivity attaining 300, response time of 100 s, and recovery time of 200 s were observed.