Synthesis, characterization and gas sensing performance of nano-crystalline ZrO2, 5%Y/ZrO2 and Ag–5%Y/ZrO2 catalyst

Hydrothermal synthesis and comparative gas sensing properties of nanocrystalline ZrO 2 , 5% yttrium doped ZrO 2 (5%Y/ZrO 2 ) and silver coated 5% yttrium doped ZrO 2 (Ag–5%Y/ZrO 2 ) and their thick films were reported here for the first time. The obtained polycrystalline products were analyzed by various physical investigative techniques including XRD, TEM and BET surface area. Screen printed thick films of ZrO 2 and modified ZrO 2 oxides were prepared for gas sensing properties of most toxic combustible and hazardous gases CO, CO 2 , H 2 , Cl 2 , NH 3 and H 2 S at different operating temperatures ranging from 50 to 400 °C. This work investigates the use of ZrO 2 , 5%Y/ZrO 2 and Ag–5%Y/ZrO 2 thick film as a gas sensor and the annealing temperature considerably affects the sensitivity of these metal oxides towards NH 3 and CO 2 gases. The statistical analysis for gas sensitivity towards synthesized catalyst was also carried out. Further, metrological study of Ag–5%Y/ZrO 2 sensor as a function of relative humidity (RH) and light intensity with various concentration of CO 2 gas is also studied.