Application of bismuth ferrite protonic conductor for ammonia gas detection

The ammonia sensing properties of BiFeO3 (BFO) multiferroic semiconductor were investigated. The material was prepared by solid state reaction method. The sintered sample was studied by X-ray diffraction analysis (XRD), Raman Spectroscopy and Scanning Electron Microscopy (SEM). Electrical conductivity of BFO was determined by Electrical Impedance Spectroscopy (EIS) in temperature range 100–700 °C at different gaseous atmospheres. The BFO resistance responses to ammonia concentrations of 0–2100 ppm in argon were recorded in the temperature range of 300–600 °C. Similar measurements were carried out in atmosphere containing 0–2100 ppm ammonia in synthetic air in temperature range of 350–450 °C. The effect of water vapor on sensor performance was investigated. The sensor working mechanism has been explained.