H2S Sensing Properties of the Flowerlike Clusters of SnO2 Submicrotubes

A highly sensitive H2S sensor at ppm level was prepared from the flowerlike clusters of SnO2 submicrotubes. The X-ray diffraction pattern (XRD) demonstrated that the tetragonal phase SnO2 was obtained. The sensing properties were characterized by conductance in a temperature range of 160-400 degrees C. The sensitivity of the sensor was 11.07 at 0.5 ppm (v/v) H2S at 160 degrees C and decreased with increasing temperature. Moreover, no cross sensitivity was observed even to high concentrations of other gases, such as isobutene, H-2 and CO. The high sensitivity probably originates from a good circulating access of the test gas and the capillarity of SnO2 submicrotubes.