Sensing properties to dilute hydrogen sulfide of ZnSb2O6 thick-film prepared by dip-coating method

The ZnSb2O6 thick-film was prepared by dip-coating into sol solution (30.4 and 15.2 wt.%), in which fine particles of ZnSb2O6 were dispersed, followed by calcination at 500–1000°C for 1 h in air. The sensing properties to dilute H2S were examined for the films prepared under various conditions. The 0.7-μm-thick film prepared from the twice-diluted sol solution (15.2 wt.%) and calcined at 900°C exhibited the excellent sensing properties to dilute H2S. The film could detect H2S as dilute as 0.01 ppm, which was lower than the legal regulation value for H2S. The film showed good selectivity to H2S and the response was stable for repeated exposure to H2S. The film consisted of large grains (60–100 nm), which had contact with each other, and open pores (100–150 nm), which formed the well-developed channel in the whole film. This is attributable for the excellent sensing properties.