Synthesis of Nanostructured ZrO₂ for Gas Sensing Application

Nanocrystalline ZrO₂ (Zirconia) has been synthesized by a conventional precipitation method. The structural, morphological, microstructural, optical and gas-sensing properties of ZrO₂ were investigated by using X-ray diffraction analysis (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV-vis spectroscopy and static gas sensing unit, respectively. X-ray diffraction pattern and TEM of the synthesized product reveal their nano-crystalline nature with grain size 18 nm and 20 nm, respectively. Gas sensing properties of their thick films, which were fabricated by screen-printing to various gases (O₂, NO₂, C₂H₅OH, CO, CO₂, NH₃, LPG, H₂S and H₂) were tested in ambient air. The ZrO₂ thick films showed a high response and selectivity to H₂S gas. The effect of operating temperature, gas concentration on the sensing characteristics of these films towards H₂S was discussed..