Physical properties and ethanol sensing of perovskite La0.8Pb0.2Fe1−xMgxO3 compounds

The nanocrystalline La0.8Pb0.2Fe1−xMgxO3 (x = 0.00, 0.05, 0.10 and 0.15) powders were prepared by sol-gel method using the citric acid route. The compounds were investigated with regard to their composition and microstructure, using XRD, Raman spectroscopy and FTIR methods. These compounds were found to exhibit an orthorhombic symmetry with the Pnma space group. The substitution of the Fe ion by the Mg one was found to increase the resistance of these compounds, where the resistance depended on both electrovalence compensation and oxygen vacancy compensation. The La0.8Pb0.2Fe1−xMgxO3 sensors showed p-type semiconducting properties within the temperature range of 100-400 °C. The electric results revealed that x = 0.15 sample presents high sensitivity and good selectivity to ethanol gas.